U ILLINO I S UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN PRODUCTION NOTE University of Illinois at Urbana-Champaign Library Brittle Books Project, 2013. COPYRIGHT NOTIFICATION In Public Domain. Published prior to 1923. This digital copy was made from the printed version held by the University of Illinois at Urbana-Champaign. It was made in compliance with copyright law. Prepared for the Brittle Books Project, Main Library, University of Illinois at Urbana-Champaign by Northern Micrographics Brookhaven Bindery La Crosse, Wisconsin 2013 pop- F NOW ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES. MINUTES OF EVIDENCE TAKEN BEFORE THE ROYAL COMMISSION ON EXPLOSIONS FROM COAIL DUST IN MINES; WITH APPENDICES AND INDEX. VOL. II. Irerekentet to bott ouC of ~)arltament fbl Commapn of i etr llajety. LONDON: PRINTED FOR HER MAJESTY'S STATIONERY OFFICE, BY EYRE AND SPOTTISWOODE, PRINTERS TO THE QUEEN'S MOST EXCELLENT MAJESTY. EYRE And to be purchased, either directly or through any Bookseller, from SPOTTISWOODE, EAST HARDING STREET, FLEET STREET, E.C,, and AND 32, ABINGDON STREET, WESTMINSTER, JOHN MENZIES & Co., 12, S.W.; or HANOVER STREET, EDINBURGH, 90, WEST NILE STREET, GLASGOW; or HODGES, FIGGIS, & Co., LIMITED, 104, GRAFTON STREET, DUBLIN. 1894. LC,--7401.-I.] ,rice 5s. 8d. and LIST OF WITNESSES. - Name. Name. Page. 1 Page. Isaac, Thomas Daronwy - 14 34 Martin, Henry William - 26 38 Martin, Joseph Samuel Brown, John - i60 McMurtrie, J. - - 46 Dixon, Professor Harold B. - 66 Morgan, David - - 11 Forman, John - 16 Thomas, John James 51 Garthwaite, Thomas Young - 54 Wilkinson, George William - 31 Hood, William Walker 43 Woods, Samuel Ashworth, James - - Bedlington, Richard - - Brain, Frank- - - - - 61 - 21 (1: fi MINUTES OF EVIDIENCE TAKEN BEFORE THE ) COMMISSION ROYAL ON 4 EXPLOSIONS FROM COAL DUST IN MINES. At 23, Great Ge.orge Street, Westminster. TWELFTH DAY. Friday, February 12, 1892. PRESENT : TIE RIGHT HON. JOSEPH CHAMBERLAIN, M.P., CHAIRMAN. Lord RAYLEIGH. Professor I AROLD B. DIXON. Mr. CHARLES FENWICK, M1V.P. Mr. EMERSON. BAINBRIDGE. Mr. *r. JAMEs . ILSON, Secretary. ASHWORTH called and examined. 4597. (Chairiman.)You are a mining engineer, I think, at Morley, in Derbyshire P-I am.. 4598. Has your attention been directed to the question of the influence of coal1 dust in explosions P-It has. 4599. And where was it first directed to the subject ? -In North Staffordshire. 4600. Was it brought to your notice by practical experience of explosions, or in what way P-It was by explosions, beginning in the year 1875. 4601. Will you tell us about these explosions and what conclusions you arrived at in respect to them PI think the explosion that took my notice most particularly was that at Swaithe Main, at Barnsley, in 1875. There I went down the pit, and I saw the condition of the pit. 4602. What was the state of affairs there The mine had evidently been considerably disturbed, and there was a great deal of dust about, and one would think it was coke dust; it was very fine dust, and a great deal of damage was done. The part of the mine that 1 particularly inspected was a part called the slant level and the slant drift level; and there there was evidence of the explosion coming down a place from the top side of the level, and then apparently splitting both ways, both inbye and outbye. 4603. Did you come to the conclusion that this explosion was caused by coal dust P-I came to the con- clusion that the explosion was caused primarily by the failure of a safety lamp. I thought so at the time. 4604. By a safety larrip firing gas P-Originally by a safety lamp passing the flame through the gauze in a current containing fire-damp and suspended coal dust. 4605. Did the explosion extend over a considerable space P-Over the whole of the pit down below the pit level. 4606. Do you think it was carried on by coal dust PYes, decidedly. 4607. In your opinion, then, this was an explosion to which gas and coal dust contributed P-Yes, gas and coal dust together contributed 4608. (Mr. Fenwick.) What class of safety lamp was it P-It was a Stephenson's safety lamp. i believe they JE 8480. Wt, 10306. Mr. J. Ashworth. were used there all through. There were some Clannys, I Believe, but in this particular district, L believe, they 12 Feb. 18Q2. were all the Stephenson lamp. 4609. (Chairman.) Is there any other instance to which you wish to direct our attention ?P-Then there was another case of a blown-out shot at the Sheriff Pit, Silverdale, in 1878. In this case the disaster did not go all the way through the mine, although it was a case of a very heavy blown-out shot. One man was killed and two boys were smothered by the dust, but the latter were not burnt at all. 4610. How was it that the explosion was not continued throuohout the whole of the mine P-I think in that case that the dust that was in the air carried the flame tp some extent, but it did not explode; the dust itself did not explode, and I do not think there was any quantity of gas found. I inspected the place myself after the accident, three or four days afterwards, and I found no gas whatever. I could not find a trace of gas. 4611. Then you think that the explosion, as far as it went, was partly due to coal dust ?-I think that the very fine coal dust prevent in the air contributed to carry the flame from the blown-out shot some considerable distance. I think the distance to where the miner was burnt and killed was about 60 yards, and I think that the flame, assisted by the dust floating in the air, was carried from that blown-out shot to that distance. 4612. Did you notice anything which was likely to have arrested the explosion at that place P-Nothing at all. 4613. There was no wet place P-I do not remember seeing any wet place at all. It is a very dry mine, 4614. That was at Silverdale P-Yes. 4615. In what seam P-The 8-feet Banbury seam. 4616. (ProfessorDixon.) That is a dry seam ?-Yes. 4617. (Chairman.) Then is there any other explosion which you have had experience of ? -I have investigated two other accidents. I investigated one last year at the Ashton Moss Colliery; that was a blown-out shot, in which there were two men killed. 4618. And was coal dust concerned in that ?-I do not thin; the coa dust ignited any more toen it did ir A 2 Mr. J. Ashworth. 12 Feb. 1892. ROYAL COMMISSION ON EXPLOSIONS FROM the case at Silverdale. I do not think there is any evidence of a coal dust explosion there. It was a very dry mine. 4619. What was the second one ?-The next one was at Sladderhill, in North Staffordshire. 4620. I think you have omitted one to which you intended to refer, the Wood Pit, at Haydock P-Yes. 4621. Will you just deal with that first, then P-In that case I think the explosion was caused by a Davy lamp, and that the coal dust there decidedly did explode, but that was accelerated by and mixed with fire-damp. I think it was fire-damp there. I do not think it was dust by itself. 4622. Now, speaking generally, do you think that the part played by coal dust in explosions is important enough to justify special attention ?-Yes, I do. I have not seen the Elemore Colliery, in the north, but I assume the Elemore Colliery and the Altofts, which I have seen since the accident, were decidedly coal dust explosions, and without any admixture of fire-damp whatever. I do not think there was any fire-damp whatever in those two cases. 4623. These explosions are initiated generally, are they not, by the explosion of a shot P-The Elemore Colliery and the Altofts were both originated by a shot. I assume the Llanerch Colliery explosion in South Wales to have been originated by a small explosion of gas and carried on by the dust; and that it was mainly a coal dust explosion. 4624. Dealing first with the explosions which are due to blown-out shots, have you studied the question of explosives generally P-I have. 4625. What is your opinion, in the first place, with regard to, say, gunpowder in blasting ?--I have taken great interest in gunpowder, especially some few years ago, and I have read several papers before the North Staffordshire Institute. I had a table prepared by Dr. Carnelley then of Owen's College, Manchester. I specified for certain quantities of coal dust and aqueous vapour and fire-damp, and a certain weight of gunpowder, and that the shot should be a blown-out shot. I asked him to calculate the chemical effects on the atmosphere all the way through. I have here the tables that he prepared. First of all he gives the chemical composition of the atmosphere before the explosion. Then he takes the atmosphere after the explosion, and also the atmosphere thait was finally left after the fire has returned, that is the explosion goes outwards, and then the fire burns backwards, burning the carbonic oxide, thus showing finally the atmosphee created by the explosion-the probable atmosphere created by an etplosion in which fire-damp a blown-out shot and the or dinary condition of a mine are taken into account. (Handing in table. See Appendix XIV.) 4626. What object had you in view in making these calcilations P-The object was to show that iF you used a pow'der of good quality, that is the very best powder that could be produced, and a powder of a certain density, and that powder was fired by a detonator, you could fire then with almost abesolute safety, whereas if you used a common powder you were almost certain to have a diasaster. The powder that r have been taking nost interest in, and the powder that I believe is a safe powder is onle, I think, only manufactured by Curtis strong mining-I aid Harvey, called E.S.M. -extra believe thhat is the interpretation; however, it goes by the initials of E.S.M. That powder detonated is, I know as a practical fact, from three to four times as stiong as ordinary blasting-powder. The composition is something similar to the powvder used by the Government for cannons, ordnance work; but the powder is not so dense. In fact it is not a dense powder at all, and the consequence is that if you fire that powder by a detonator each grain of powder is practically ignited at the same instant. The consequence is that if you get a blown-out shot you get no particles of the powder blown out unconsumed; each grain of powder is consumed. I have used that powder myself under certainly dangerous conditions, and I never had a single accident in any shape Or form, and never had'a blown-out shot with it. 4627. Assuming the use of this powder in a mine in which gas prevailed, do you mean to say that a blownout shot 'With it would not 'be dangerous, that it could not explode the gas P--I think it would be very difficult to get a blown-out shot; but if you got a blown-out e shot with that powd r, I would not s y that you would not get somewhat of a disaster because you, get a flame, but each grain of powder being ignited at the same COAL DUST IN MINES: instant of course the condensation of those gases and the cooling of those gases takes place immediately, and if the ramming or stemming gives way then the condensation is going on and the cooling of the gases is going on the whole of the time, the only question is, of course, whether those gases are cooled down sufficiently by the time they get outside the borehole as not to ignite firedamp. It is proved now that if you can reduce the heat of the explosive by the time it gets outside the hole under, I think, 2,732 degrees Fahrenheit, then you cannot ignite the gas; so it appears that if you can get gunpowder even or any other explosive and can absolutely say that by the time the heated gases get outside the hole the heat is reduced down under that figure, you will have no disaster. 4628. Are you aware whether there have been any experiments to show whether this powder can or cannot explode gas P--I have made experiments myself, of course in the ordinary course of working; but no experiments to show (that is in a tube or any prepared gallery) that any required effect would result. 4629. You could not say, then, as a matter of absolute certainty, that even with this powder gas might not be exploded, and a general explosion set up P-No; I cannot say so. I do know this, that in consequence of the present investigations going on into explosives, Curtis and Harvey have got the matter before them at the present time, and, I believe, will certainly bring that same powder out in a little different form, but so constructed, and so protected, that when the gases get outside the borehole the heat will be so reduced thAt it will absolutely not fire gas, providing, of course, the hole is stemmed. You must have the hole stemmed. I do not think any explosive-I do not mind which explosive it is-is safe without stemming on it, not any of them. Every explosive depends for its safety entirely, all the high explosives at any rate, on the strength of the detonator. If the strength of the detonator is weak or the composition of the explosive happens to be altered a little bit, and detonation is not complete, you get a flame and you are as liable to have a disaster with a high explosive if it is not properly detonated as you are with the best gunpowder. 4630. Have you any practical suggestions to make then with regard to detonators or with regard to stemming P-I think the most practical suggestion that I should make is that taking ordinary gunpowder as it is generally used in a hole with a diameter of from 1 4 inches to two inches, generally the whole is practically of two inches diameter, that every explosive should be used in a hole of reduced diameter in proportion as it is stronger than gunpowder. For instance, if you take E.S.M., this extra strong mining powder, as an illustration, if you use the ordinary powder in a two-inch hole I should use the E.S.M. in a hole not more tanu an inch and a quarter in diameter. The practical effect is this, that if you get a hole of a certain length we will sa-, supposing the powder fills up the hole to the 7ength of 12 inches you have a 12-inch leverage. Then if yoiv get a stronger explosive, I say that that stronger explosive ought to be laid along the hole for 12 inches, or ought to rest along the hole for 12 inches if it is to be compared in strength for coal getting with gunpowder. There is another advantage in it also, that if you take an inch and a quarter diameter hole compared with a two-inch hole you have a greater superficial area here in an inch and a quarter than you have in the two-inch for the same weight of powder. 4631. How does the reduction in the size of the hole lessen the chance of explosion P-It lessens it in'this way, that a smaller length of stemming then secures the charge. Sir John Burgoyne in a little book that he plublished on blasting and quarrying proves that two ounces of powder in a two-inch hole will blow out not more, I think, than 20 inches of the best clay stemming, the best stemming that you can put in. He tried several shots, and two ounces would not blow out more than 20 inches of stemming. Then if you get the same weight of powder in an inch hole, seven inches of stemming will hold the same strength of powder, seven inches will hold it secure. It will not blow out more thaii seven inches of stemming. 4632. 1 suppose the larger the hole the looser the stemming, and consequently the easier it is pushed out P-The diameter, and of course the area on which the pressure comes, is larger in the two inches than it is in the one. The French Commission have made some experiments upon that, and I think, if 1 remember aright, they issued a decree that no shot should be fired T MItiNUTES OF EVI DE NCE without a certain depth of stemming on the top of it; not less than 20 inches. 4633. But your idea is, that the strongest possible explosive should be used, and in a proportionately smaller diameter of' hole P-No, I do not quite say s,-. I do not say that you should use the strongest explosive. 1 say, supposing that the explosive that you use is four times the power of the ordinary powder used, I should reduce the diameter of the hole in proportion; I should only make the diameter of the hole one-fourth of that used for the powder. So that whatever explosive you used, you would reduce the diameter practically in accordance. I think it is hardly practicable myself to get the hole much under an inch ; I think about an inch would be about the smallest diameter I should use, but still you can bore an inch readily. Then, of course, for the question of safety, you must be particular that the quality or the sort of stemming that you use is not coal dust, nor the same as was used in the Sladderhill case-a blackberry dirt-I think they called it blackberry dirt. That blackberry dirt would, of course, cause a flame of itself. 4634. Is there any other suggestion you have to make with regard to explosives P?-I think that as far as the ise explosives is concerned, it is very important that of the explosives should not be used in any case where you have ropes or chains, or rails, or signal wires anywhere in the line of fire. 4635. Why P-For this reason. I find in investigating the accidents, we will take, for instance, three of them as cases that might be followed out and the facts investigated and also discussed fully (those are the Elemore, the Altofts, and the Sladderhill cases), in all those cases we have ropes or chains or pipes and signal wires all present. My own opinion is, that in t4hose cases the friction and the heat of the explosive blowing out across these various ropes and chains and rails and so forth, set up an electrical condition, and that it is the electrical condition which is set up which disturbs the dust all along the roads. 4636. Is not the concussion sufficient to disturb the dust, without any theory of that kind P--I think not; becahie if you take cases in which you haveehad blown-out shots in mines equally fiery, and equally severe blownout shots, you have had no general disaster throughout the pit. I think if you compare those cases together, that you have a complete proof that there is a certain effect produced in the cases I have mentioned which is not produced in other cases. 4637. On the other hand, in the experiments which have been made, an explosion has been-set up without any of those conditions, showing, does it not, that coal dust alone may be exploded by a concussion P-Yes; but I think that in all the experiments that I know anything at all about, the coal dust has been led into the test apparatus, whatever it may have been, in such a quantity, that if you were in it yourself you could not breathe at all. Trhat is not the ordinary ,ondition of a mine. The ordinary condition of a mine is, that you have a certain amount of coal dust floating in the air, which we will take it is the very finest coal dust you have got. It is proved by the experiments of Mr. Garforth and his microscopical tests, that that coal dust is of a peculiar nature. If I remember rightly, from Sir Frederick Abel's experiments, the coal dust that was explosive was the coal dust which had the smallest specific gravity, and, therefore, that shows that the very fine coal dust must be something different from the ordinary coal dust that we find in a mine. I take it, judging from Mr. Garforth's experiments and his investigations, that each particle of that fire coal dust we see floating in the air, very probably if it were collected and put under the microscope, would be proved to have those little cells, those little spores, each spore being surrounded with a certain small cavity, and that it is that cavity which really makes the difference in the specific gravity. That is my view of it. 4638. Now, I think you are of opinion that the question of safety lamps is also an important one in considering this subject ?P--I consider that it is a very -important one. In 1879 1 was asked by the North Staffordshire Institute to come over from Wigan to start their experiments in safety lamps and put them in a way of getting them carried through, and on the 3rd September 1879 I went over there, and when I got there the illuminating gas that they had at command was not sufficient to foul a 10-feet current. The consequence was that if we were to conduct the experiments at all, we must resort to some other means of endeavouring to get an explosion. With that object we took some of the Banbury dust from Sir George Elliot's Collieries at Warecastle, that was spread on the floor of the and test tube. The test tube had an area of 12 inches by 6, and 1 should think that it would be about 20 feet long, and coal dust was just spread on the floor of the tube. We started with a velocity o'fabout 370 feet per minute. Then, to test what the condition of the atmosphere was before the lamp was put in, we had one of Ansell's fire-damp indicators. This was put into the tube to test the per-centage of gas. The per-centage cf gas was. I believe, generally speaking, about 41 per cent., which, of' course, was of no use to explode he lamp in by itself; in fact, we did not expect to get an explosion. However, that was the extent of the fouling of the current by fire-damp. We then put a Davy lamp into the tube, and that Davy lamp failed (very unexpectedly, I may say) in 20 seconds. This Davy lamp had on the intake side a shield, the ordinary tin shield that was generally used at that time, and the lamp failed with a velocity of 370 feet in 20 seconds. t-feet 4639. Whiat did that show P That showed that a Davy lamp in the presence of coal dust, the coal dust being simply licked up from the floor of the tube, was unsafe. We had no coal dust disturbed in any way at all except by this small velocity. The consequence was that the coal dust we had in the air there would fairly represent the coal dust that you would find in an ordinary dry and dusty mine, such as Altofts. We went on then to make further experiments-4640. You were saying what the failure of the lamp showed P-The lamp showed this: that if it were present in an ordinary mine and you had, we will say, 4J per cent. of gas, and if the man had his lamp hung up in the ordinary way, be would never perceive that there was anything wrong with it, he would not perceive that 4- per cent. of gas if it were behind him and he were working; he would go on working without taking any notice of it, probably, but if suddenly anything that happened should disturb the dust, and he want his lamp, that lamp would fail in 20 seconds. As a practical application of this, I may go on to say that I: consider the Haydock explosion at the Wood Pits to have been caused in this way whilst a man was cutting a thirling through between two levels. If I remember correctly, this man was found blown through a small cutting that he had just nicked through between two levels. The air previously to his nicking through had gone along the level, then back again along the bratticing, then down a thirling. then up : another level, and then back again along the bratticing. The consequence was that as soon as the thirling was cut through the whole ventilation would pass through it, and as the lamp would be on the cutting side and in the direct line of the dust and the air, as soon as ever he nicked through the extra ventilation would disturb the dust behind. The gas present in the air (and there is very little doubt there was gas present in the air there) combined with the dust, carried the flame through the lamp, and started that explosion. That is my view of it. I think also that one of the accidents at Leycett (I do not remember the date of it) was caused in a similar way. You may remember that in that case there was a man working in a place where an air-pipe ventilated a heading; it was not a case of a bratticing, it was a case of an air-pipe blowing on to his lamp. I think that that case was also an instance of a small per-centage of gas combined with coal dust. Shall I go on and state t he other tests that we made at Harecastle in September 1879 P 4641. If you please P-The next test was with a Davy lamp, and that fired in seven seconds in the same velocity. The n.,ext test was with a Clanny lamp, and that fired in 25 seconds; and each time the explosion happened the coal dust on the floor of the tube was ignited. The next test after that was a Davy lamp in a velocity of 570 feet per minute, and that exploded in four seconds; in that case the shield was down on the return side, the opposite side to the first experiment. The next test was with a Davy lamp with a double gauze, and that exploded in 3 minutes 47 seconds. The next lamp after that was a Williamson, in a velocity of 570 feet, and it exploded in 55 seconds; the shidld in this case was on the return side at the top of the gauze. The next test was also with a Williamson and in a velocity of 580 feet per minute, and that exploded in 55 seconds; the shield was on the opposite side, the intake side. The next test was with a Clanny, in a velocity of 580 feet per minute, and that exploded in 35 seconds. The next test was with a Stephenson lamp, A2 Mr,. J. Ashworth. 12 Feb. 1892. ROYAL COMMISSxfON Mr. J. Ashworth. 12 Feb. 1892. oN EXPLOSIONS FROM in a yelocity of 580 feet per minute, and that exploded in 42 seconds. The last test was made with a Gray, the velocity being 580 feet per minute; the gas continued to burn, and the experiment was suspended; that lamp did not fail; it was the only one that did not fail out of the lot. 4642. What precautions, then, do you think it is necessary to take to prevent the failure of the lamp PI think it is necessary with every safety lamp, if the mine is a dry, dusty mine, giving out fire-damp, unless the gauze is specially protected, that that lamp should have two gauzes. For instance, where a Cl.nny lamp is often used it ought to be a lamp of the Marsaut type, that is, with two gauze.s, or the gauzes protected in such a' way that the air of the mine and the dust cannot impinge directly on to the gauze. As actual instances of the failure of lamps under conditions similar to those tested at Harecastle, I give that of the Morfa Colliery in South Wales, where a lamp which is called a Marsaut lamp, but which was really a Clanny lamp, failed in a place called the Six-and-a-Half; and that of the Mossfields Colliery in North Staffbrdshire where a Museler lamp failed in the north level of No. 15 jig. 4643. Now will you just name in their order the precautions which you think it would be desirable to take to prevent explosions by coal dust or connected with coal dust. In the first place, with regard to the working of the mine, do you consider that it is desirable to water the mine, for instance P-I do not think water is of any value whatever. If you were to carry out the present Act and water the places about a shot, you do as much practical good as you do if you pour water on to soot, and that is simply that it hangs about on the soot in a sort of little globules; the soot is not damp and the coal dust is not damp, and any watering that you do like that is of no value whatever. You will not prevent an explosion by watering; and the only value of watering, as far as I can see, will be in arresting an explosion by having thoroughly wet places in the road. You can have these thoroughly wet places in various parts of the mine, and you may be perfectly certain, or practically certain, from the experience of explosions, that the explosion will not pass those points. 4644. What lengths .of wet ground do you think necessary to arrest an explosion P-As far as the actual proofs go, you are perfectly certain that 70 yards is quite long enough, and it is very probable that a good deal less than that will do. 4645, Then coming to the blasting process, what precautions do you say are necessary there ?--First of all, lthe diameter of the bore-hole should be properly regulated, and in a dry and dusty mine the non-use entirely of ordinary black powder. The ordinary black powder is not of good enough quality. If you are to use powder you must use powder of the very best quality. If you use powder of the style of the E.S.M. -I do not know any other powder that I can compare it with ; but if you use it of that class and detonate it (every shot should be detonated), I think that we'shall then have got some measure of safety, or about an equal measure of safety to that which you will have with the ordinary high explosives. 4646. Have you anything to say as to the position of the shot ;-Yes; I think that no shot should face the current, no shot at all should face a strong current ; the stronger the current the greater the danger. As far as you can arrange it, the force of the shot should always go with the current. 4647. How do you consider that these explosives should be fired P-Electrically, always. 4648. I think you have already told us that you consider the diameter of the bore-hole and the question of leverage should be carefully attended to P-Decidedly. I think the question of leverage is most important. If you wish me to give a case, a case of which we have all the published facts, then Sladderhill is a very good instance. In that case the explosive only filled up, I think, about 2 inches or less of the length of the hole, and the hole with that length of explosive in it, was practically on the fast, and that shot blew out, and in blowing out blew this blackberry dirt out, and then the force of the flame which was created was fired into a mass of fine coal dust, and also crossed the rails and the pipe. I do not think that that accident would have been so severe if the shot had not acted, as I have just stated before, electrically on the rails and pipes before it, because the shot was distinctly in the line of the rails. 4649. Have you anything to say about the so-called flameless explosives P-I do not know really at present COAL DUST IN MINEI': which explosive is flameless under all conditions. If tests are made on explosives, I should propose that they be tested with the bare fuse as well as with the detonator, simply because a shot fired with the bare fuse would represent a weak detonator; a weak detonator would have the same efl'ec prob)ably as a weak fuse, and the effect produced on a high explosive by a weak detonator is totally different from the effect produced by a detonator of sufficient power; in fact, in some cases it has been shown that part of the charge is detonated, and part of it is not detonated. 4650. Then in the present state of knowledge you would suggest that flaimeless explosives should be protected P?-Yes, they ought to be protected. 4651. Have you considered the subject of further experiments for the purpose of determining some of the questions which are still in doubt ?P-Yes, I have. 4652. What conclusions have you formed upon that ? -I have come to the conclusion that the proposals which have been made so far are simply repetitions of the experiments which have been made on the Continent, and experiments which have been made, I think, by the Chesterfield Institute, and on the general line on which experiments have been made heretofore, that is, in a straight gallery or tube. I do not know a single case in which they have had any velocity of air passing at more than 6 feet a second, J think at Chesterfield they had 6 feet a second. If you carry out experiments to prove anything you want a velocity corresponding with the known velocities in cases such as Altofts and Elemore, and Ashton Moss for instance, in which the velocity would range from 30 feet to 50 feet per second. In such a case the coal dust that will be put into the apparatus, whatever the shape of the apparatus, would be licked up by the wind as it went past, and would represent the ordinary conditions that you have in a mine. If you simply have an open tube, and you fire shots into it, then, I suppose, you would have to have, as Mr. Galloway said. a very fine coal dust and pour it in. Then you would show that you got an inflammation. I do not know that anybody disputes that. There are very few people who will dispute that coal dust will inflame or explode under such conditions. But that is not the condition of a mine. Therefore, I should propose that you have con. ditions similar to what you find in the mine, that is, you should have a velocity of air passing at from 30 to 50 feet a second, with a water gauge of not less than 21 inches; and if necessary, in the course of the experiments, I should also propose that you had rails and ropes and chains to prove whether what I have suggested previously is a fact or whether it is not, that certain electrical conditions are set up which disturb th. dust from the tops of the timbers and the sides of the roads. 4653. You said something about the previous experiments ha. ing all been conducted in a straight tube ?I think they have all been conducted in a straight tube. 4654. Then what shaped tube do you propose, or what plan of tube P-I think that you should have a tube made in wrought-iron box girder form, about 30 inches square. I think that would be sufficient, but you must have it long enough. Take the Altofts explosion, fbr instance. There was a space there of about 150 yards, that is, from 70 to 80 yards on either side of the shot, in which practically no damage was done. I take that as being the combusting chamber, in which a second explosion takes place, that is, the shot blows out into this area, is mixed up with the coal dust thereabouts, and as soon as sufficient air is mixed with the unconsumed powder it bursts into a second explosion, and I consider that the second explosion follows the electrical conditions which throw the dust into the air, and that then the flame spreads throughout the mine instantaneously. I do not think that there is any question of seconds in it. I think it is an instantaneous explosion from that point. 4655. Have you any plan or sketch of the proposed tube to carry your idea out P-No, I have not. I only just made a small hand sketch, which I sent in, and which I think represents practically the workings at Altofts or the roads at Altofts, that is, a straight tube with the higher workings on, the air going round the higher side and also round the lower side, and the return air-rvay with the crossings in. I think if it were made in wrought-iron, if it were necessary you could extend the length or shorten the length, or make any combinations of those tubes that you choose. INUT E S Of"EV 11NCHS 4656. What length do you consider the tube should be ?-Certainly not less than 150 yards in a straight line, that is, irrespective of the higher side and the lower side workings. I think also that you should have what you may call an i:ipcast pit and a downcast pit. If these two were represented by a syphon-shaped tube, then I think that you would be able to get. a fan and all the mechanical arrangements of that class handy to the place, and also regulate the pressure in such a way that we could get any water gauge that might be desired. If a tube of that class were made, of course there might also be windows or other means of detecting the way the explosion passed, so that you could follow it all the way through. Upon this electrical business, which I think is a point rather fresh in the matter, I went down last night to the Crystal Palace, and I attended Siemens' lecture on some electrical experiments. I tbink there is a matter there that possibly might be carried out, which to some extent follows some suggestions made by Mr. Garforth. In that case they photograph, or rather project upon a screen, the vibrations of a telephone, and by that means any particular vibration produced by the explosion could be projected on the screen in a similar way; and if, as I suggested, there is the detonating vibration created by a blown-out shot, you could have that vibration distinctly shown on a screen, and if you choose you could have it photographed for reference, and it would prove more distinctly than anything that could be said what really takes place, whether it is a detonating vibration or simply the passage of a flame as a flame, or whether the dust is disturbed by the soundwave and is then followed by the flame. I think that you would prove the whole thirg in that way by the use of the telephone. In the middle of this telephone Siemens had a little mirror; the light shone on the mirror, and then the vibrations were projected from that mirror on to the screen. 4657. (Lord Rayleigh.) With regard to the different explosives, do you think that experiments conducted with the various kinds of powder and with other explosives would be of importance P-Yes; I think so, decidedly. 4658. Such experiments could be conducted without any very expensive appliances, could they not P-Yes, I think so. 4r659. You attach a good deal of importance, I think, to the manner in which the stemming is conducted ?I do, 4660. Would it be possible, supposing that regulations were made, that they could be effectually enforced in a pit P-Yes, I think so; because you see in a mine that is dry and dusty any blasting that takes place is even now conducted with a good deal of care-with a great deal of care in fact, and I think after the explosions we have had and the experience we have had in mines using candles and where explosions have occurred, that people are inclined to be more careful than they have been. 4661. So that you think there would be really no practical difficulty in enforcing any restrictions which might be imposed ?-I think none at all, especially in regard to the hole, because' all the tools would be sharpened and made in the colliery shops, and the blacksmith would regulate the size. 4662. And with regard to the depth of the hole and the depth of the stemming ?-As to the depth of the hole, I think that in no case should a fireman or deputy fire a shot without he saw the hole before it was charged. Accidents have happened where the deputy fired ,a shot without knowing what the hole was, whether it was a deel) hole, or a shallow hole, or whatever it might be. He ouht. t also to see the hole charged. It-does not take a long while to charge a hole. 4663. To pass to -mother matter; you were speakin.. just now of experiment s in a long gallery of iron of somewhat limited dimensions. It has been represented to us that no experiments would convince practical miners unless they were conducted in a gallery of almost the same size as the actual galler of a mine ?I should rather prefer that they were conducted in a very large gallery; but the expense of making such a gallery and repairing the damage done would be very great. Of course the pressures would be very great in a gallery anything like 8 feet square; and if you got a gallery of 8 feet square, if it were a straight gallery of 150 yards long, it would cost a lot of money. 4664. Apart from the question of cost, would .it not be difficult through such a large gallery to mnaintain the current of air which you think important P?--I do not think it is necessary, and I would not suggest that it is at all necessary to have so large a gallery. I think if you have somethinig about 30 inches square, which a boy could creep up and either sweep it out and see anything in it, or make any alterations which you might think necessary, so long as the size was sufficient to do that, it might be 3 feet square. I think that would be found amply large enough. 4665. Do you think that the results of experiments conducted in such a comparatively narrow gallery would be accepted by the mining world as conclusive on the point P?-I think s,). We are hardly supposed nowadays to be quite so simple as in times back, neither the workman nor others. We are all supposed to be a little bit better educated than we used to be. 4666. (Mr. Bainbridge.) Have you read most of the evidence already given before this Commission FI have. 4667. What would you wish us to understand then generally has been the chief points that you wish to put forward as new matter in the evidence which you have given this morning P-I think one principal thing is how it is that coal dust is disturbed in a mine in the case of these big disasters. Another is, of course, this question as to how explosives shall be applied. 4668. Especially with regard to the stemming. I think the disturbance of coal dust. and the manner in which it is disturbed has already been brought before us pretty fully P-I do not think anybody has suggested that an electrical condition is set up in the mine which disturbs the coal dust, that is what I mean to suggest. 4669. That is what you refer to P--I suggest that. 4670. That has been referred to by one or two witnesses with regard to the Elemore explosion as being a cause ?-I think they said in the Elemore case that it was lightning. I do not suggest lightning at all at Elemore. 4671. No, they said as far as they knew, if you remember, that there was an absence of coal dust, and an absence of fire-damp as well, and that they could not make out therefore what caused the explosion, and it was suggested in a somewhat vague way that it was the presence of electrical conditions P--I did not read that. 4672. However, that may be. I think you will agree that the term " electrical condition " is rather a vague term ; we should be very glad if you would explain a little more fully what you mean by the electrical condition ?-I am not an electrician myself, but I think that there are certain electrical conditions which may be produced in the mine from the rubbing of the chains for instance, and that sort of thing. A chain after being at work a long time in a mine is very considerably magnetic, I take it, and if you have the force from a blown-out shot to beat, and the stemming forced out by friction and shot across these various things, that is rails, ropes and chains, and signal wires, then you have electricity set up. I do not know how it exactly happens, how it takes place, but a sort of electrical wind takes place, and throws the dust off the various points all along the road. In that way the whole of the atmosphere of the mine is charged with dust, and then it is ready for what I should call the det nating effect which takes place from the second explosion, that is the explosion which takes place in the chamber, we Will say of 150 yards long, a sort of dletonating vibration which it spreads right away through the mnine. 4673. That, however, is a suggestion, is it not, entirely unproved by any practical experiments, or by any explosions which have taken place ?-I think the explosion at Udston in Scotland was a decided case of detonation. 4674. 1 am referring to the electrical conditions that you spoke of; there is no case that you can mention where that suggestion of ycurs is at all proved by any aggravated explosion that is due to those conditions. For instance, at Altofts, where they had all these conditions of ropes and chains and rails, there was a very big explosion, but for all that you know the explosion might have been equally great and severe if those things had not existed P-I do not say that myself, for A3 Mr. J. Ashworth. 12 Feb. 1892. RIOYAL COMMISSION ON EXPLOSIONS Mr. I do not know what exactly disturbed the dust, and J. Ashworth. put sufficient in the air in the small time that the explosion occupied to cause the disaster as it hap12 Feb. 1892. pened. 4675. You mean that you think the blown-out shot which happened there could not have been enough to do that P-I do not think it was enough of itself. 4676. It must have required some other conditions which you think existed in the presence of the chains and other iron work in the roadways f--Yes. I find that in Elemore and other cases they are always present, and that if you take a contrary case such as that in the Sheriff Pit at Silverdale in which you have three shots prepared, two of which were actually fired, and one of them was a blown-out shot; you have there a dusty mine, you have all the other conditions, except that you have not these ropes and chains and signal wires, and so forth, anywhere in the line of fire; there was nothing of the sort in the line of fire in the 8-feet Bahbury at Sheriff Pit, and, of course, in that case the disaster was simply local; the flame was, no doubt, aggravated by the coal dust floating in the mine, but it was not a coal dust explosion, the coal dust was evidently stirred up, because the two boys were smothered with coal dust. 4677. Now, with regard to the question of blown-out shots, of course you know what a blown-out shot is due to in the first place, do you not P-To the failure .of the stemming. 4678. That being the case, the question of one kind of powder or another will not make much difference, will it P--Yes, it makes a great deal of difference. If you get a powder which is very dense, it is well known, of course, that the powder when it is ignited simply burns continuously all the way through, it does not spread to all the grains at the same time. What I say about powder is this, that if you detonate powder and you have a powder of little density, as little dense as possible, you then, by means of detonation, ignite each grain at the same instant, and you do not get the projection out into the mine in the case of a blown-out shot of any unconsumed grains. In all these cases, where you get unconsumed grains thrown out into the mine, then as soon as they find sufficient oxygen to complete the combustion they break out into a fresh flame. 4679. You suggested that this E.S.M. powder would be less likely to produce a blown-out shot than an ordinary black powder P-Certainly. 4680. Given 6 inches of stemming and the same size of hole, and the black powder used in one case and the E.S.M. powder in ,another, the E.S.M. powder being stronger would be more likely, would it not, to blow out the stemming P-If you get a strong explosive the stronger the explosive and the more downward the effect, the slower it is and the more pressure; that is, it is more of a pushing nature. If you get a powder of a high density you simply push the ramming out, and as the burning is going on the whole of the time then you get a very big flame. But you do not get a very big flame, at least I have never seen a flame at all with the E.S.M., and there is very little smoke with it. 4681. Have you tried the E.S.M. powder with a very small quantity of stemming, or rather have you tried it with a view to induce a blown-out shot P-No; I have never made any arrangements to get a blown-out shot. 4682. That is the true test, of course P-I have never made such a test as that. 4683. The real test of the E.S.M. powder is not what it does when tried under natural conditions and with a proper quantity of stemming, but what it does under unnatural conditions, and with a too small quantity of stemming P-When I have suggested all these sort of things to people they say, well, you must not suggest anything of that sort, you must suggest that the powder is used properly, and you have -no right to suggest that the powder should be fired without any stemming at all. 4684. Do you suggest that this powder is sufficiently safe to use when you want to depend upon the absence of flame ; I mean would you use it yourself in a fiery mine P-In the present state of our knowledge on the subject I do not think I should use the E.S.M. powder except it were further protected. I am told by Curtis and Harvey that if it had not been for the influenza laying up their officials, we should be in a position at FROM COAL DUST IN MfINES" the present time to know what their experimen-ts had resulted in. They are experimenting with a view, too, of improving this E.S.M. powder and making it sufficiently safe, or as safe as any other explosive, and I believe myself that they will succeed. 4685. Is it not a fact that what yout term a further protective is a source of great danger if placed in the hands of a man on whom the stemming depends P-The difference is here, that in this case the protection will be a part of the explosive, that is, it cannot be separated, it cannot be left out, it cannot be taken away from the explosive in any shape or form whatever. If you get the explosive you have got your protection, and when you put the explosive into the hole you know you have got both your force and your protection at the same time. Any explosive which is protected by water or by any special covering is liable to create a disaster, because as it happened at Sladderhill, the man left out the water; he simply was too idle to get the water, and he put it in without the water, and caused a disaster. I do not hold to one explosive more than to another, but I hold that every explosive ought to be made as safe as it can be with the present knowledge that we have of explosives; but I hold that the protecting part should be-so combined with the explosive that when you put the explosive in you have got your protection in at the same time. It is possible. 4686. Do you know of any explosive just now which is so safe as to be safe with an inferior quantity of stemming, and supposing the stemming ought to be 8 inches and you put in 2 inches is there any explosive that you know of in existence that would be safe under those conditions ?-There is an explosive I have read about-I do not know anything more about it than what I have read--and that is bellite. No other explosive occurs to me at the present time with which there has not been some accident. There are two explosives which are largely used now, and they are said to be absolutely safe, those are securite and roburite, but there have been accidents with both of them, and therefore we are certain that when there have been accidents with these things that they are not absolutely safe; they are absolutely safe, I suppose, if you fulfil all the conditions. 4687. Can you refer us to any coal mine at present which is using the E.S.M. powder now ?-It is beinag used by myself; but I cannot say for anybody else; I have not asked, in fact. 4688. With regard to your statement as to the temperature of 3,600 degrees, being that at which the flame will not impart an explosion, what evidence have you got of that P-The French Commission stated 2,7320 F. 4689. You did not mention the authority P-I take that from their evidence ; they say that if you can reduce the temperature down to that point you will not ignite your mine. 4690. In regard to the firing of shots, you have made a special point of the question of leverage, do you not think that the question of doing the work by the explosive depends very much upon the particular point where the shot goes back against the slines or partings of the coal, is that not almost as important as the leverage P-In coal getting, I presume you mean P 4691. Yes, in coal getting P-I do not consider that that is a point at all; I consider that leverage is the great test point, because if you get close, against a sline, and you get a large diameter of hole, and a short length of powder, if that hole is put in as far as the sline, then the powder expends its force down that sline, and not in the shape of leverage to fetch coal down; it has gone there, it has not gone to the leverage. If the powder is spread along the hole, even if the sline is close against the shot you lose part of your powder or your explosive into that sline. You have just got a long length of leverage, and that length of leverage will very likely fetch down your coal in spite of the sline taking away some of your strength. 4692. I do not doubt at all the importance of leverage; I am rather pointing to this, is not the question of getting the explosive at the right point a very important one in relation to bringing down the work P-I think it is very important indeed. 4693. Almost as important as the leverage P-Do you mean to say that if you get the explosive at the back end of the hole then you clear your coal out for a certainty to the back of your cutting ? MINUTES OF EVIDENCE. 4694. Yes P-I think that I prefer that you get the leverage even if you leave a bit of coal on. 4695. Now, you spoke about rather a novel point, namely, that it was important in dealing with the different exploites to reduce the size of the hole for the stronger explosives P-Yes. 4696. You do not suggest that there is any novelty in that, do you; you are aware that now, when any higher explosive than gunpowder is used in coal mines, it is an invariable rule to reduce the size of the hole P-I do not think it is the invariable rule; that is just what I think; it ought to be an invariable rule, but I do not think it is. 4697. 1 suggest to you that it is the invariable rule ? -At Sladderhill they used the higher explosive in the same sized hole that they use the powder in. 4698. What high explosive did they use there PGelignite, or gelatine dynamite. 4699. In the same sized hole P-Yes, and that was where the two ounces of explosive were bottled up just at the very end of the hole, and I think according to the plans, it was really on the fast. 4700. Surely you know that in general practice the reverse is the case ?-I do not know. 4701. Did they use a water cartridge there ?-The water cartridge was not used in that case. 4702. Were they in the habit of using it ?-Yes, they were. 4703. In the absence of water, are you aware that whenever a higher explosive than gunpowder is used the diameter of the hole is reduced P-I have been decidedly under the impression myself that the same diameter of hole has been continued; if it is altered it is altered recently. I do not know myself that it has been altered. I hope it has. 4704. You may take it from me that quite the reverse is the usual practice. In reference to the safety lamp experiments which you mentioned, where the 4 per cent. of gas was used, did you try an experiment in that case without any coal dust P-Yes 4705. And with the 4y per cent. of gas P-Yes. 4706. And no explosion took place ?-We got nothing at all; the lamp was not affected, and burnt as happy as Tnossible. 4707. Having found that 41 per cent. with this coal dust produces an explosion of the lamp, have you happened to try any lower per-centage of fire-damp than that, say 2- per cent. P-No. 4708. You did not try anything further P-No, I did not. My time was exhausted then, and I did not go into North Staffordshire again after that. If any further experiments were made they were made by the Institute Committee, with which I had nothing to do. 4709. In this experiment which took place, of course the gauze of the Davy Jamp during the few seconds during which the experiment endured, got gradually redder P-Yes, it got red hot. It did not get what you might expect if you had pure fire-dauip. If you had pure fire-damp I think the gauze would have been very much hotter. 4710. You have mentioned the case of an explosion, I think, with the Marsaut lamp at Morfa P-Yes. It was called the Marsaut lamp. but they had taken the inside gauze out, and it was really a Clanny. 4711. It is well to have put that right. You said the Marsaut, which was the same as the Clanny?--Of course a Marsaut is not the same as the Clanny-they called them Marsaut lamps, but they were Marsaut lamps with the inside gauze taken out, and that reduced them to the Cianny. 4712. A sort of emasculated nMalsaut. It was the Clanny that was used P-Yes. In that case I would suggest that there was some disturbance in the goaf close against the 6, and that possibly forced out some gas, or something of that sort, and that it was not a blown-out shot; the indications there point to its coming from the 64, and not being a blown-out shot. 4713. You suggest 70 yards as being the length of damp ground which would arrest an explosion, but have you any case in point P?--I take the Morfa. In Morfaall the men in No. 7 got out, and they were protected by a length not exceeding, I think, 7(0 yards, 4714. Then dealing with the preventives which you mentioned to the Chairman, you spoke rather strongly against the value of watering the dust. Are you aware that we have had witnesses before us, I daresay you may have noticed their evidence, who have said that where watering in South Wales is properly done, that is, commencing by making the dust damp, and keeping it damp by regular watering, there is no such effect as you mentioned in the water coming away from the dust P-Yes, I am aware of that. 4715..Would it not in that case strike you that the watering is effective P--I do not think it is of any value whatever from that point of view. I have seen Mr. Stokes, the inspector of our district, who went to South Wales to see this watering, and he says that he went down there and found the air so saturated withb water that they had to provide the people working on the roads with flannel suits, but that as soon as ever you take your stick and just stir up the mere crust on the top of the rest the dust is there, and as dry as if it was never watered. and it is on the roof and on the timbers and actually on the water pipes that are carrying the water. It is only a mere shell covering it, and if you disturb that covering by anything that you like you have the dust there still; that dust is not saturated in any sense at all; it has merely got a damp covering, a damp top. 4716. I put to you a case quite different from that where witnesses have told us that the original dust is made thoroughly damp, and then kept damp by frequent watering. Do you suggest that no such a case exists ?-I do. I think the dust is as dry as tinder underneath; it is simply a skin of damp on the top, the natural heat of the mine would dry it. 4717. In any case, from that point of view, you would advise, though you did not mention it as a preventive, that the alternative process of constantly removing the Just would be a wiser one than watering P-I think so. together with thoroughly wet patches here and there on the road, I think that would be a good deal more effective, Of course, I am not going to run down the watering as done in South Wales, because it is a very sanitaiy matter; it makes the road a good deal pleasanter to travel on. At the same time I am not at all certain-if you experiment, of course you will be able to ascertain it-that if you have a certain amount of aqueous vapour in the air, and a disaster takes place that it does nut help it along. I think you will perhaps be able, when you come to experiment, to prove that the aqueous vapour may help; I almost think it does myself. 4718. The provision you require of wet patches would only be a way of reducing the extent of the explosion ? -Certainly. 4719. But preventing -the explosion is far better, is it not -to aim at the first cause, and to remedy that ?I propose that, of course, the first cause shall be protected as far as possible by applying the knowledge that we have, or that you will be able to furnish us with, as to the proper use of these explosives. The other matter of using the sprays of water. I take it, is a very importantI sanitary matter. I do not say anything against it at all, but I simply say that I do not think it is a preventive of an explosion. 4720. You mentioned as another preventive, that no shots should face the current; what was your idea in proposing that P-I take it, at Altofts, and also at Elemore, and I think I may say generally in every big disaster which has occurred from a blown-out shot, the shot has always faced the current. 4721. At Altofts I may correct you, perhaps, it was at right angles to the current ?--They do not seem quite certain about that. They say so far as they can tell, it was at right angles. I should say myself that the way they put it in shows rather that it might be to a certain extent at right angles; but I think it inclined a lit towards the pit. 4722. Do you think that a blown-out shot which caused an immense explosion anywhere would have avoided causing an explosion by its direction being changed ?-If that shot at Altofts had been the opposite way round, I do not think it would have caused an explosion. 4723. In that particular case ?-Yes, I am rather inclined to think it would not have done so. 4724. Mr. Garforth was not of that opinion, was he P -- I never asked him. I think it is a matter that you will be able to prove distinctly. A4 ,Mr. J. Ashworth. 12 Feb. 1892. 8 ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST 4725. Then with regard to the use of the electric current instead of a fuse, your suggestion is, I suppose, that there is more safety in the electric firing than in 12 Feb. 1892. the fuse firing; but do you in that case think that the fuse firing is unsafe P-I do not say that it is altogether unsafe, because you may fire the fuse withoutn igniting the gas; at the same time the electric fire is the safer of the two. I do not say that you cannot fire it with a fuse with safety, but at the same time I say the electrical is the safer plan. 4726. With regard to the question of the examination of the hole before a shot is fired. I daresay you may know that in some well regulated mines it is the practice to have every hole examined before the collier fires a shot P-Certainly it is. 4727. You rather mentioned it as being a 'desirable precaution to take P-Yes, because -I know it is not done everywhere, but at the same time, the regulation might be added, that it must be examined before the shot is fired. I have had a case myself, where there has been a blown-out shot (which did not cause a disaster), where the hole was not examined by the fireman before he fired. 4728. With regard to your suggestion as to the gallery being 2 feet 6 inches square, I suppose you prepared this sketch you have brought before us in order to obtain as nearly as possible the condition of a working mine P-Yes. 4729. Do you not think this would be equally as useful in case we have a gallery going, as you put it here, a certain distance, and having angles in it of the same kind. So long as you have several angles it is not necessary to go all round the square shown in your diagram, is it ?-The question at Altofts was that this explosion turned at right angles, and it seemed to prefer going away to the right rather than taking the shaft just close to it ; that is the only thing in it. I only drew that sketch as representing roughly the roads of a pit, and it may be either extended or lessened according to circumstances. I do not say that all that is absolutely necessary, except that you should have a tube not less than 150 yards in length, and carried round to form a square so as to obtain compression by the collision of the forces which are trying to escape from the centre of the explosion. 4730. You do not suggest that this idea of making the ends of a syphon form is of any particular service; so long as you get an opening of some kind there is no advantage in having it in a vertical direction PExcept for convenience. 4731. Would it not be very convenient to have an open end horizontally P-Of course, if you put angles in it will almost come to the same thing as my syphon. 4732. Except this, that there would be the advantage of having horizontal ends as they are now arranging it on the Tyne, at N'ewcastle; the observer can immediately walk in and see what has happened during the explosion; whereas if you have shafts vertically arranged it will be rather difficult of entrance, unless you have doors at the bottom P-In that case, even if you carried out that, I should suggest that you have places where, by taking out certain bolts, you can get access to any part in the same way. 4733. In your replies to the Chairman you did not make any reference to the comparison between lamps, which is made in the paper, a copy of which has been sent to us. Do you wish to make any remark upon that P-As to the detection of fire-damp, do you mean P 4734. I think what you have done here is rather to describe the Peiler lamp, and another lamp which you thought was equal, if not superior, to the Peiler P-Of course, if you are going to fire any explosive in a dusty mine it is of the gr(at est importance that you detect very small per-centages of gas. The Peiler lamp, not being a sate latip, that is from its cubic capacity, it will fail in an explosive atmosphere, even if there were no velocity, I set to work to try and make a lamp of ordinary construction, which would give equally sat isfactory results. By using, if you like to use alcohol spirit without a light, you can get a perfectly safe lamp, and you get a shorter cap with the same cer. iainty that you do in the Peiler. The caps in all the covered lamps are shorter than they are in the exposed lamps of the Peiler because, of course, the atmosphere of the mine comes in contact with the flame of the latter lamp at every point, of course it is fed from every side, the consequence being that you get a Mr. J. Ashworth. IN MINES: very long cap from a very small per-centage of gas. If you have a spirit flame placed inside a safety lamp of any construction you like, Gray's, or whatever it may be, you get a shorter cap even with the same flame, so that you can make these detections if you like to use the lamp; the only thing is that I suggested benzoline or colzaline, as the protector people call it, as being a means of carrying a flame which will illuminate your way, as well as being a good hot nonluminous flame for making tests for gas. We found with the benzoline flame reduced and perfectly nonluminous that you have got a test with which you can read down to - per cent. 4735. Then you referred to the colzaline lamp from that point of view; having, as it has, about the same illuminating power as an ordinary colza lamp, you regard it as being more useful for testing gas than the ordinary protector lamp, would you say, to commence with P-No, not the ordinary protector lamp; as far as the illuminating power is concerned I do consider it good; but, in the ordinary protector lamp, the lamp bottom is held by a shutter which simply slides over. If your lamp bottom is hot, as it generally is in a dusty mine, then there is vapour given off the whole length of the time that you are using the lamp; and that vapour escapes through the shutter hole, and then, as I know from my own experience, it works up through the coarse screw and fouls your test, as people often say you find gas where there is no gas-you may find gas in the cabin at the pit bottom. Now, if instead of making the shutter hole simply solid, if you screw that down and make it perfectly air-tight-4736. As you have in your improved lamp P-Yes; and then carry a small tube up the centre of your wick which is perfectly free, to the inside of the lamp and to the outside of the lamp, then any gas created inside the vessel comes up this tube, and is burned in the flame and does not vitiate your test; it forms part of the flame then, and then you have nothing except the air of the mine to give you the test for gas. 4737. Is this new lamp in practical use anywhere now P-There are a good many out now; mostly they are in use at some of the naphtha works. Curiously enough there are two in use, I think here in London, and one at Turney's Works at Nottingham. Those works are something in the leather business, they use some volatile and explosive liquid. 4738. I mean are they now in use in any coal mine for the purpose of testing any quantity of gas P-There are some few. 4739. Whereabouts P-Generally speaking people say they find plenty of gas with what they have got. I think I had a dozen of those lamps made and there are 11 of them in use. Do you mean to say, is there any demand for them P 4740. No; I do not ask that. I mean, is any mine now using them for the purpose of testing gas in smaller proportions than they were able to find with the Davy lamp P-There is one at Ashton Moss, and Mr. Grundy, one of the inspectors for Lancashire, is using one. 4741. With regard to the Peiler lamp, you mentioned that it was an unsafe lamp; with what velocity of fiery current do you say it explodes ?-I think it will explode with no velocity at all-in a still atmosphere. 4742. Has that experiment been tried P-Judging from Marsaut's tests that lamp will explode readily. I have always been instricted myself that if you go with a Peiler you have first of all to test with an ordinary lamp to see whether the atmosphere is explosive. If it is not explosive then you are to use your Peller, but you are not to use your Peiler first. 4743. Then you suggest that if a man goes into a place to test with a Peiler for y or - per cent. and he finds the atmospheric condition is explosive there will be an explosion P-I think the chances are that there would, I should not like to do it myself. 4744. (Mr. Fenwick.) I think you said that you had been using the E.S.M. powder yourself P-Yes. 4745. -lave you had much experience of its use P-I have always used it in every condition in which I thought there was any risk whatever. If there was any place where there is any gas about I always use it. 4746. You never had any knowledge of a blown-out shot P-None at all, not a singe case. MINUTES OF EVIDENCE. 4747. Do you suggest that that fact is due to the quality of the powder used rather than the carefulness with which the shots were prepared P-Principally to the powder itself; to the sudden and the complete combustion taking place before anything gives way the combustion is complet ; ii is alacys detouite((l, ~ used with a detonator. 4748.. Did you take the precaution to examine in every case the hole before the shot was inserted P--Not myself; of course the officials have. 4749. You seem to attach a great deal of importance in your evidence to the stemming of shots. You are aware, no doubt, that the Act of 1887 prohibited the use of small coal for stemming P-Yes. 4750. Do you think that that provision is very generally enforced P-I think it is generally; at the same time people sometimes take the handiest thing. In the case at Ashton Moss (that was only last year), they simply took the dust off the floor, coal dust and all the stuff mixed together, simply wetted it, and put it in the hole, and that was used as stemming. In that case there were two men killed. That shot did not blow over the rails at all, it blew straight down an air-way where there were no rails, no plates, or anything at all. 4751, You seem also in your evidence to suggest that it would be desirable to leave a little of the coal that was holed on, rather than to run any risk by shutting it all off -Yes, I should prefer that point too, but, as Mr. Bainbridge has said, if' a ,nan cuts to a sline or a face at the back he would not naturally put his shot to touch that sline, he would leave some little piece on, perhaps an inch or two, and then it would be sire to fetch it up to there. 4752. Are you not aware that in most instances when a workman cuts to a sline or a parting in the coal he is unaware of sIa. fact that he the done so P Of course I have got Derbyshire in my mind at the present time, and the slines there. They generally do cut to a sline there. 4753. Has the workman any knowledge that he has done so ?-Yes. 4754. Are the slines there open ? - He decidedly knows that they are there inr that particular case. 4755. (Mr. Bainbridge.) How does he know P-They find them distinctly in the case that was in my mind just then; the slines are well .defined. 4756. Do they find them with the drill P-Not with the drill but by cutting, because the cutting would be made first, of course, and then the drilling would be done afterwards. I do not think that the diameter of the hole will lessen the chance of kicking off to the back, not the least in the world, because the pressure would be there the same. 4757. (Mr. Fenwick.) Have you any suggestion to make as to the best material to be used for the purpose of stemming P-I think the ordinary floor dirt, I mean to say the marly floor dirt; you cannot mend that a great deal when it is damp. 4758. Would you suggest that in any amendment of the Mines Act the examination of the hole and the preparation of the shot by the fireman prior to the charge being inserted should be made compulsory P -Yes, I think that it ought to be a compulsory matter that the fireman before he fires the shot should see the hole and should have the opportunity not only of testing the hole, but that he should see it charged; it is not a long matter to charge the hole, he would not have long to wait. 4759. Then with regard to your statement that no shot should be fired facing the current, do you suggest that that should apply to all shots or only to shots that are fired in the main roads ?P-1 think that that is only of great value whitre you have a very strong current, and that itn an ordinary coal face you have not; you very soldom have there any current of from 30 feet to 50 feet a second. I only mean that'to apply where you have a very strong current, and that is principally in the main roadway. As to the coal face where there is an ordinary current passing, I do not think it would matter at all, because there is no large quantity of fine coal dust anywhere about. I am told that the French Commission proved that it was danger. ous to fire a shot directly facing waste or gobbing, that is, if you have a waste with a broken down place in it, Fj 82480, it is dangerous for the shot to face that on account of the compression, but I do not know for a certainty about that. 4760. Are you aware that it has been stated in evidence here that a blown-out shot in the coal face Neits the cause of the recent explosion at the Apedale (Clliery P-Do you mean Sladderhill ? 4761. Yes, it is called both Apedale and Sladderhill P -Yes. That was in the heading; it was in the coal face. 4762. It was fired against the current P-No; excuse me, there was no current at all. If you refer to the plan of the shot itself you will see that it does not face the current ; it does not face it in any way; the air-pipe did not come as far as the end of the heading. 4763. Do you suggest that there was no air coming in here (pointing to the plan) P-There was only a blow just there; there is no velocity anywhere there. 4764. But still, to some extent, it must have been against the current P--No, I do not hold that it is against the current there. 4765. Would you think that it is practicable for shots that are fired in the working face to be fired otherwise than against the current ?-I do not make any rule about facing the culrrent as far as concerns shots fired in the working place, for the simple reason that I do not consider there is any great danger in facing the current as far as I know, unless the current has a velocity of about 30 feet per second. 4766. Then your suggestion would particularly apply, as I understand, to shots that are fired in the main roads ?-Certainly (pointing to plan of the Apedale explosion). There are rails in this case; but in many of the explosions there are no rails. That shot blew straight away here on to those rails and into that coal dust. I suggest, according to this electrical theory, that it disturbed the dust lying here and carried the flame ; I do not think the flame from there caused the entire loss of all those men. I believe that electrical condition is always suspended once it comes to a wet place, then whatever electricity is present makes earth at that wet. 47e7. On the question of lamps, you seem to attach very much importance to the character of the safety lamp which is in use in fiery mines Are you acquainted, I suppose you are, with the report of the Royal Commission on accideits in mines P-Yes, 4768 Especially with regard to the experiments that .they made as to the comparative safety of the lamps in use P-Yes, I am acquainted with that report; but, you see, in that report there were no experiments at all made with coal dust and safety lamps. 4769. Are you aware of the experiments that were tried, particularly with the Davy and the Stephenson lamps P-Yes. 4770. I have no doubt you are aware of the fact that, under certain conditions, the Davy lamp, when it was encased in a tin can, was the safest of all lamps employed P-It is a safe lamp in a case under those conditions. 4771. But without that protection it was the most dangerous of all P-I do not know that it is anrty more dangerous than the Clanny. 4772. Are you aware that that is the report of the Commission P--Judging from my own experiments, a Clanny lamp fails nearly as soon as a Davy lamp, that is, if it is unprotected. 4773. Would you agree with the finding of the Com. mission on that point P--Without coal dust, yes. I should take that, because when you are experimenting you cannot get the exact conditions always the same. 4774. Would you suggest that when the Davy lamp was used in an explosive mixture it should have the pmotection suggested in the report of the Royal Commission P-I should not use the Davy lamp, and I should inot like to know that the Davy lamp was used otherwise than protected. A Davy lamp protected as we often find it nowadays, in the presence of an explo. sive mixture such as I have stated without coal dust, is safe, but I do not know whether it is safe with coal dust. 4775. (Professor Dixon.) Did you visit the Sladderhill Pit after the explosion P - No, I have not visited Sladderhill. 13 Mr. J. Ashworth. 12 Feb. 1892. 10 ROYAL COMMISSION ON EXPLOSIONS 4776. Then you do not know it personally ?-I do Mr. J. Ashworth. not. I only know it from reports. 4777. Do you know where the rails are laid in the 12 Feb. 1892. levels there P- Yes, they come right opposite the heading where the shot was. 4778. Are they laid in both levels, in the lower one and in the upper one P-Yes, in both levels. 4779. And do the rails reach to the last thirling PJudging from the drawings they did. 4780. The pipe did not reach as far P-Not quite. 4781. I might correct you there ; there were no rails P -I thought the rails were represented on the plan. 4782. No, I examined the pit myself, and there were no rails, and the pipe did not come opposite the thirling, it stopped some feet before it got there, so flame could not have blown over the rails or pipe P-Only where it burnt that heap of dust; there must have been a very large flame, and that pipe is very close to it. 4783. It was not in a direct line P-No. 4784. I wanted to call your attention to that. Would you explain what you mean by the leverage of a charge P-(Illustrating.) Supposing this is a piece of coal which has to be blown off, the hole is placed in we will say so, and the leverage that I speak of is represented by the length that the charge lies along the hole. 4785. Why do you call that leverage P-You see it is holed in under here, it is vacant here, and the leverage is from here to there. 4786. The length of the charge you call leverage PThe length of the charge is leverage. 4787. You spoke of a second explosion occurring. I think, if I remember your words aright, you said unconsumed powder is blown out from the shot hole and may be fired when excess of air reaches it, or some words to that effect P-Yes, when there is additional air mixed with it. I will give you an instance that I have seen myself which would very likely be a good sample of what can happen in this case. It was at an ironworks. In cleaning the tubes from the furnaces to the boilers at certain stated intervals they brush out a large amount of soot and unconsumed carbon of some sort. This is cooled with water on the inside and then scraped out through manholes at the bottom. In the case that I saw myself, as soon as the stuff had dropped down I should think about 4 yards below the piping in a black mass it suddenly burst into flame. If you take a blown-out shot in like manner to that you have unconsumed grains of powder. I am supposing the stemming as being either dust or containing carbonaceous matter, it is all at a high heat, and mixed up with the unconsumed grains of powder, and as soon as ever that gets mixed up with sufficient air it bursts into a second explosion. 4788. I understand then, you suggest that the unconsumed grains of powder require oxygen in the air to burn them P-Certainly I suggest that, and I think it is certainly proved that those grains of powder are surrounded by, we will say, the products of the combustion of the other grains of powder which prevent the burning of that powder; and I have myself two grains of powder blown out of one of the l81-ton guns, which are only partly consumed; they are left about the size of my thumb nail. I suppose that the sulphur is entirely burnt out of them, and there is only the rest of the ingredients left. Those I have, and I know, of course, that these grains are blown out of guns in that way. 4789. What is the composition of the Curtis and Harvey powder which you describe as E.S.M., do you know that P-I do not know exactly what it is, I should think it is about 75 per cent. nitre, but I could get it for you. 4790. It is a powder composed of charcoal, sulphur, and nitre P-Yes, it is an ordinary powder, I suppose it is kept in the incorporating mill for a greater length of time, rubbed together very carefully, and then the powder cake is not pressed to such a large extent as ordinary powder. 4791. Is it a quick-burning powder P-Yes.. 4792. Then you said that you had calculated the constitution of the atmosphere of a mine previous to an explosion, or that Dr. Carnelley had done so for you PYes. 4793. How does that effect the question, whether dust will be fired by a blown-out shot ?-It was made in FROM COAL DUST IN MINES: that case to prove that an atmosphere which is not explosive in the ordinary way, becomes by the addition of these other ingredients an explosive atmosphere, at any rate you will get an atmosphere left which will burn after the shot is fired. If you look at the table which I have put in,perhaps you will understand my explanation. 4794. How does the constitution of the atmosphere affect the question whether dust will be fired if a shot blows out P-You get the blown-out shot and then you get the addition of the dust for the second explosion; you have got additional carbon and you have got additional oxygen. 4795. Do you mean by the second explosion a second after the shot itself P-Yes, after the shot itself. First of all your shot blows out, and that shot which blows out consists as we may say of unconsumed grains of powder; supposing there is coal dust in the stemming, there is that coal dust, and then you get additional coal dust in the atmosphere along with the additional oxygen, and that bursts into either a second explosion or a second violent inflammation, whichever it may be. 4796. I thought you said that after the coal dust in the air had been ignited the air came back again and you had a second burning of carbonic oxide, I think you said, and that that was the second explosion PThat is the third effect. 4797. So that you have three explosions following a blown-out shot P-Yes. It was known, in olden times at any rate, I have read it, 1 do not know it for myself, and I have never seen it done, but I have been told that years ago the colliers working in a heading where they were short of ventilation purposely under-powdered their shot, and then when the gases from the shot were oozing out of the different breaks in the coal they took a candle and fired the gases. I know a man who told me years ago that he had done it. I believe he is alive still, but I have never seen it done myself. 4798. Did you use the phrase under-powdered the shot P-Yes. 4799. Do you mean putting a little powder in ?-Yes, that is so. I was told that it broke the coal but did not fetch it down. They took the candles and lit those gases and of course that converted the gases into carbonic acid. 4800. (Mr. Bainbridge.) Do you say that in this last case they lit the gas all round because ventilation was bad ?-Formerly. 4801. Would that not make the ventilation worse by producing more carbonic acid P-Yes, but then the carbonic acid gas would occupy less space, and, of course,it would not be as poisonous as the carbonic oxide. 4802. Quite sufficiently poisonous, would it not P-[ suppose a man would get along better; that was the. principle upon which I suppose they worked. As I say, I have never seen it done myself. 4803. Do yort suggest that in every case of a blownout shot the grains of powder which come out are to some extent unconsumed ?-Yes. 4804. Do you not agree that in the case of a blownout shot it is simply a question, not of the powder failing to do its work, but finding the work through the hole easier than breaking down the coal; is that not so P -It escapes through the hole instead of breaking down the coal. 4805. So that there is no reason why the powder, in forcing all its strength in pushing the stemming out of the hole, should be unconsumed P-It does not exert all its strength. 4806. It is blown out simply because the stemming is easier to blow out than it finds the coal is. to break down P-Yes. 4807. Therefore, as the stemming is easier to blow out, there might be quite enough strength to resist it in the stemming to cause the powder to be consumed P? -I do not say that every blown-out shot would cause a disaster, because I know of a case myself where a blownout shot did not cause a disaster. That was in the Arley mine. 4808. Will it not be the exception for a blown-out shot to have unconsumed powder rather than the rule P -1 should think it is not what you may call a common case. A shot would have to be largely overpowdered to produce a case of that sort. For instance, in the Altofts case they say there might have been from 2 lbs. to 11 MINUTES OF EVIDENCE. under such conditions is surrounded by gas which prevents that combustion going on ; but at the same time the whole thing is so hot that as soon as ever you get additional oxygen you get the continued inflammation. (Professor Dixon.) I think you have been wrongly instructed. 3 lbs. of powder. Two lbs. or 3 lbs. of powder, you know, would be tremendously overcharged. 4809. (Lord Bayleigh.) A large quantity of unconsumed powder is blown out of all modern guns P-Yes ; I have two grains of it. Excuse me, about that question of the oxygen. I am instructed that a grain of powder Mr. J. Ashworth. 12 Feb. 1892. The witness withdrew. Adjourned. I At 23, Great George Street, Westminster. THIRTEENTH DAY. Friday, February 26, 1892. PRESENT: THE RIGHT HON. JOSEPH CHAMBERLAIN, M.P., CHAIRMAN. Sir WILLIA I LEWIS, Mr. EMERSON BAINBRIDGE. Mr. J. WILSON, Secretary. Mr. DAVID MORGAN called and examined. 4810. (Chairman.) You are the agent, I think, for the Aberdare and Merthyr Miners' Association P-Yes. 4811. How many men are represented in your association ?-Something like 8,500. 4812. Have you yourself worked in mines P-Yes, for 35 years. 4813. In what part of the country? - In South Wales. 4814. Are the mines of South Wales fiery mines P-Yes. 4815. Are they dusty mines P-Yes, the majority of them. 4816. Now, what effect, in your opinion, has the presence of dust in causing explosions or in increasing their effects P-I do not believe that coal dust does cause explosions, but I believe that when explosions do take place the dust plays havoc with the men after the explosion. In the first place an explosion goes along like a hurricane, and it raises the dust, and the flames roll through the dust and kindle it. A brother of mine had some experience in that direction. We were both in the pit at the time of an explosion, but I was not actually in that explosion, my brother was, and he stated that in his opinion most of the people were killed by breathing the dust which was burning in the interior after the explosion. 4817. Now, with regard to the commencement of an explosion do you think that a blown-out shot will ignite the coal dust P-That depends upon the nature of the blown-out shot. A blown-out shot does not at all times create a flame, but there is a possibility, as I have seen it before now, of a blown-out shot creating a flame, and that flame reaching the gas, and the gas igniting, and hence the explosion. I do not believe that a blown-out shot of itself will ignite the dust, and Lhrough the dust make a terrific explosion. 4818. Have you seen any account of the experiments which have been carried on with coal dust P- No, I have not witnessed the experiments myself but I have read a little of them, and I have heard gentlemen whom I could believe say it is the case that coal dust does cause these explosions, but I have not seen it. I will admit this, that there are different kinds of coal, and. therefore, different kinds of coal dust; and Ihave no doubt but what some kind of coal is more explosive than others, but I have not witnessed it; and I do not believe that the coal dust in Wales is so sharp that it would ignite at once, by the light of a candle as it were. 4819. Supposing that an explosion of gas takes place, do you think that that could be carried on to greater distances than it would otherwise go by the presence of coal dust P-Most decidedly. 4820. Therefore, in your opinion, the presence of coal dust in a mine is an increased source of danger PThere is no doubt of it in my mind. 4821. And do you think that where coal dust is present the explosion is likely to be more fatal than it otherwise would be ?-Yes ; especially when the place is extremely hot; and then the smaller the dust the more effective it is. 4822. That being the case, what precautions do you think ought to be taken in order to prevent this danger P-The best precaution that I could suggest is that the coal dust should be removed as far as practicable, and be watered in order to put it down. 4823. Is watering generally practised in the South Wales mines P-Y es. 4824. Does it have the effect of keeping the coal dust damp P-Yes, 4825. We have been told that the water remains on the surface and that the coal dust underneath the damp layer on the top is perfectly dry, and might just as well produce an explosion as if there had been no watering at all P-I have seen that allegation by Mr. Galloway, if I remember rightly, who has written a very good book on the question, but he goes to extremes, in my opinion. I believe the colliery managers and the colliery owners all round are much more careful of the dust and clear it off much better, and so they do not keep such a stock of it now on the roads as they would, and they are watering to my knowledge with pipes on the main roads, and so keep the dust pretty well damped down. I believe that the collieries are better ventilated and kept in better health than they were some 20 or 30 years ago. 4826. Have you given any attention to the question of explosives P-Yes; explosives are very good agents in coal getting, and it is very desirable, in my opinion, to get explosives which are not inflammable. 4827. So as not to produce a flame, you mean P-Yes. 4828. Are you aware of any explosives which can be relied upon not to produce a flame P-No, but I have seen a test made of the bellite powder, and I did not see any flame created by that. They tell me that in certain experiments made afterwards, someone, I presume owing to a very great extent to competition between the different patentees, did succeed in getting flames from everyone of these explosives, but I was not present at the experiments myself. I was, as I say, B2 Mr. D. Morgan. 26 Feb. 1892. 12 ROYAL COMMISSION O)N EXPLOSIONS present at an experiment tried with bellite powder, and then I did not see any flame at all. 4829. Is powder much used in the South Wales 26 F'eb. 1892. mines P-Yes. 4830. Do you think that it on ght to Ie prohibited P-No; I hope not at any rate, because it would be a most detrimental blow to the South W'a,les mines, and colliery owners as well, to do away with it. 4831. Are not what are called flameless explosives as good as the powder ?-No. The bellite powder has been tried, and another powder composed of lime and some chemicals, but they were not so effective as gunpowder. 4832. Is not gunpowder more dangerous in regard both to gas and to coal dust ?P-Yes, there is no doubt about that. 4833. But you still think that the risk ought to be taken P?-We are justified, in my opinion, in running some risk at all times rather than to do away with the working of the coal mines. Of course we ought to do everything we can to avoid explosions, but whatever we may do and whatever we may say we will never get rid of them altogether; we must have some risk, and I have no hesitation in stating that if you would do away in Wales with powder as an agent that would be the means of stopping something'like one-fourth of the collieries, because it would create an increase of labour which would increase the cost of production, and so stop the collieries. 4834. Can you say why the blasting by flameless explosives should be more difficult and more expensive than blasting by common powder P-Somehow they do not produce the same results, not nearly the same. Where we have rock it is very difficult to gt these powders, such as bellite and the lime mixture I spoke about, to bring the rock down in much of the hard ground which we have in Wales, in some cases at any rate. 4835. Have not the explosives that you are talking of, such as bellite, as great an explosive force as powder P-No, nothing like it. 4836. Do you use water cartridges in Wales P-Yes. 4837. Do you like them P--I have not had experience of the water cartridges myself, and therefore I cannot say, but I know that they are used in Wales. They are not used to a great extent, they are only used where they are essential, because of the water. Mr. D. Morgan. 4838. Is there anything else you wish to state to the Commission in regard to the question we are investigating P-No, I do not remember anything else. 4839. (Sir William Lewis.) You referred to the means of watering; have you seen the most recent means adopted, where the water is provided in sprays and carried in with the intake air P?-Yes. 4840. Do you consider that is a very great advantage in the carrying on of our dusty mines P-Yes, it is excellent. It is improving the health of the horses and of the men, and in my opinion enables the colliery owners to work more coal out upon the same ventilation. 4841. Would you, from your experience, say that where that is done effectually the use of gunpowder could be continued with little or no risk in carrying on our collieries P-Yes. 4842. Without resoruing to anything in the shape of cleaning, or of an examination of the place beyond what is now provided in the 'Act of Parliament P--I believe that it is necessary to clean the dust, because, as the Chairman has just intimated, if you leave a thickness of dust. say to the amount of 6 inches, then if you water that the dampness will be on the surface, but in many places where I have been the watering is done so effectually as to go through, say, 2 inches of the dust. 4843. So that where the dust is not removed from time to time or kept, at all events, down to a very thin covering, it would be dangerous to continue the use of powder, would it not P-Not where you are watering; that is where the watering is thick. 4844. But where the watering only penetrates, as was suggested by the Chairman, just through the covering of the thick layer of dust P-Shot-firing by means of an inflammable explosive should not take place in such places, in my opinion. FROM COAL DUST IN MINES: 4845. But you have had no personal experience with any of the flameless explosives P-No; only I saw the experiment which I told you of at Werfa. 4846. Are you quite clear as to bellite and those other explosives not being sufficietl:iy strong to break down the hard ground in our district P-I have not had much experience; I only saw that one experiment, and therefore I cannot go so far as to say that they are not altogether effective ; but the experience of the men points in that direction. They have tried the roburite powder at the Plymouth collieries ; but the men went against it altogether because they could not think of using it-it was ineffectual. 4847. Was that for want of power or because it gave off' any objectionable fumes after the shot P-Both. 4848. Which was the greatest objection. Supposing it dia not give off those objectionable fumes, would it be an advantage to use that rather than powder P-No; I believe, according to the evidence that I have from tho men, it was so ineffectual that they could not go on, and it was much more expensive. 4849. Then you said that blown-out shots did not always give off a flame ?-Yes. 4850. Are you speaking now from personal observation P-Yes. 4851. In the greater number of cases blown-out shots do give off a flame, do they not P-No. 4852. Have you ever seen them give off any flame P -Yes. 4853. So that where you have a blown-out shot, and where there may be dust and a possibility of any gas in places where you could not detect it, that would be attended with considerable danger, would it not P-Yes ; but in my opinion before the coal dust will ignite -in Wales at any rate-the place must be rather hot; and in such places I would prevent shot-firing altogether, except you got a powder which would not give off a flame. 4854. At all events, if you could get the same power you would think it a very great advantage to have a flameless powder ?-Certainly so. 4855. Then you also said, in reply to the Chairman, that you did not think a blown-out shot could create an explosion; what had you in your mind when you said Assuming there was gas existing within the that. range of the blown-ont shot, do you suggest that that would not create an explosion ?-i mean this; if a blown-out shot had no flame it would not create an explosion, and if it had a flame, if there was no gas to feed it afterwards, there would be no explosion-of any magnitude at any rate. 4856. No; but you have had sufficient experience in places where you have been working to assume that gas may be lurking in a place which you could not possibly ascertain, even by examination, previous to setting off a ihot P-Yes. In that case of course when a blown-out shot gives off a flame, and that flame reaches those cavities, it might create an explosion-and it would. 4857. Have you anything to suggest to the Commission by which the risk attending the carrying on of operations under those circumstances could be reduced P -The only way is, in my opinion, to water the places as much as practicable, and another thing, to get flameless explosives. 4858. That would be dispensing with the use of powder, because powder is not flameless P-Exactly, if flameless and effective powder can be got. 4859. You admit that P-Yes. 4860. Would you say that every care is taken in examining the places in the immediate neighbourhood where shots are proposed to be fired P-I would not go so far as to say that every care is taken, but I believe that the practice in this case is very good. 4861. You have nothing to suggest by way of additional precaution in that way, have you P-No. We have careless men, of course. I believe they are well instructed. The law, in the first place, in itself is a precaution, and if the law is carried out it meets the case, but we must admit that there are some men in the collieries, the same as in every other business, who are not altogether at all times up to their business, but the practice is very good on the whole. 4862. Now in many cases, as you know, in our district powder is used not only for hard ground in MINUTES I: OF EVIDENCE. ripping the top or in lifting the bottom, but also in coal P-Yes. 4863. Would you say that there would be an advantage in dispensing with the use of powder in coal getting, and in limiting its use to the hard ground ?As I have said before, it means stopping something like one-fourth of the collieries in Wales. 4864. Do you think so P-Yes. 4865. What additional cost would you, as a practical man, say would be imposed upon the owner if with respect to coal itself there was no powder used ?I have no hesitation in stating that it would create upon one-fourth of the produce something like 6d. a ton. 4866. Is it not the fact that powder is very largely used in coal getting where it is not necessary P-I would iiot put it largely used in that direction, but I believe that there is more powder used than should be used. 4867. And that it would be a very gr'eat advantage if it was limited in its use in the actual coal gettingP--I believe that much of the powder which is unnecessarily used is used by unskilled labour. It is much easier for a man to be taught to use the drill and to put in a shot, than it is for him to be taught to trim the coal the same as it was 20 and 30 and 40 years ago. 4868. And would there not 1)beanother very great advantage in limiting the use of powder, that coal would not be so broken up as it is whore powder is so extensively used P-There is no doubt about it. 4869. (Mr.Bainbridge.) Before you and Mr. Isaac came here to give evidence, did you have a meeting with the council of your miners' association ?-No. 4870. Then, are you giving your own evidence without any conference with your fellows P-Yes. 4871. It is entirely on your own account P-On my own account. 4872. In answering Sir William Lewis' last question with regard to there possibly being too much powder used in your district, you were referring, I suppose, to South Wales only P-Yes. 4873. And you have no knowledge of whether that answer would apply to ajy other pFart of England or Wales P-No. 4874. Now, with regard to shot-firing. Would yon kindly explain the manner in which the shot is fired iII your district P Who drills the hole P-The coal cutter. 4875. And who fires the shot P-Where the safety lamps are used, a special man goes to do it, but where they are using the naked lighis, the men do it themselves. 4876. Where safety lamps are used, a special man goes round and fires the shots P-Exactly. 4877. That special man does not examine the hole which is being bored, nor the quantity of powder put into the hole, does he P-No. 4878. Does he make any inquiry as to the quantiUy of powder put into the hole P-No. 4879. Then that is left entirely to the judgment of the collier P-Yes. 4880. With regard to the question of the safety of a shot generally, I suppose you would say that in order to prevent blown-out shots, and their consequences, you would first of all examine the district to see there is no gas and no danger from gas ?P-Yes. 4881. Would you not also consider it rather an important matter to see to the condition of the hole, and to see that the right quantity of powder is safely put in anl the ramming properly done P-Yes. 4882. Would not that reduce the number of accidents if that were more properly watched P-.-Yes; but if the colliery owners were to get menl to do that, they would have to put on four men to look after that business instead of the one that they have at present. 4883. You think the number of men required to do that would be so great .- Yes. 4884. And that that would be a serious cost P--Yes. In my opinion it would have been a better remedy to teach the men to understand their own business than to get other men to look after them; to teach every collier, before he had a place to himself, what is the proper way to cut coal. I believe there ar great defects in that direction in collieries at present, so far as Wales is concerned at any rate. I have no doubt they are as well up to the mark in Wales in that respect as at other places, but then I have no practical knowledge of other places. 4885. You think that besides the natural experience which every collier gains year after year in constantly fi in' shot te ought to have some specific training P4886. That would be useful to him P-Yes. 4887. So as to be able to judge both as to the quantity of* powder, and the quantity of ramming, and the de')th of the hole, and so on ?-Exactly. 4488. But I suppose by degrees your men get extremely skilled in that way P-Yes. 4889. So much so, that it is a very rare thing to find a blown-out shot P-Yes, they are getting better all the time according to their experience. 4890. Now withregard to these blown-out shots, have you had much experience of them P?-I do not remember many that took place with myself, to tell you the truth. 4891. How imany have you seen in all your career P -I could not say. 4892. Fifty P-Much more. 4893. Blown-out shots P-Yes, hundreds of them. 4894. Hundreds of blown-out shots P-Yes. 4895. Would you not say that it was more the exception than the rule to find them free from flame P Is there not more often the presence of flame with a blown-out shot than an absence of flame P-No, it is an exception to get a flame. 4896. That is your experience P--Yes. 4897. With regard to the question of watering, you would soy, I suppose, that there were two modes of dealing with coal dust, one the watering, and the other the removal of the dust P-Yes, but you could hardly ever remove the dust in collieries so clean that it would not be necessary to water. 4898. Then to which process do you attach the greatest importance P-To both of them. 4'99. Which chiefly P-The watering, I should think. 4900. 1 suppose that it is partly because it is almost next to inmpossible to remove all the coal dust to make it safe P-Yes. 4901. Then you find that the watering really does have the effect of making a damp mass around the places, and thus practically removing the dust in itet dangerous form ?-Yes. 4902. It has been put to us here that the watering in many places does not succeed, but, as Sir William Lewis suggested to you just now, it forms a coating on the top of the dust. Is it your experience that as a rule in South Wales it does succeed P-My experience is that of late years the colliery owners do look after it-the managers at any rate do. They remove the dust very well on the whole, and afterwards they water. 4903. First remove and then water ?-Yes. 4904. And they see that the watering is done properly P-Yes. 4905. Then with regard to the question of dealing with the coal dust, the general effect of your evidence is that you think there is no scope just now for taking f'u rther precautions P-No. 4906. That is so P--Well, I believe there is a possibility of applying science to the explosives, so that we may get a powder like the lime mixture, which will be effective in doing the necessary work. I am no chemist myself, but I believe that it is possible to apply chemistry to the lime process, and it may be, to the bellite PSo far as I am aware, as I told the Chairman, bellite does not make any flamie at all. 4907. You are doubtless aware that the lime cartridge has been in use for many years ?-Yes. 4908. Especially in Derbyshire. Has it been used in South Wales at all P--Yes. It has been tried. We used lime in South Wales, I can remember, so far back as 40 years ago, but there were no chemicals mixed with it then, it was used in its natural form--rude-the lime itself only being pushed into the holes at night, and water being put in after it, and against the morning it would squeeze down the coal. 4909. The only difference between 40 years ago and 10 years ago is that it was put in roughly then, and B3 Mr. D. Morgan. 26 Feb. 1q92. 14 ROYAL COMMISSION ON EXPLOSIONS 10 years ago it was used in the form of a cartridge PYes. 4910. But I daresay you know that the lime cartridge 26 Feb. 1992. is not now in use, except upon a very small scale P-It was tried in Wales as an experimeint by Mr. Casey. I saw it tested at Powell Dufferyn, and I thought then that it would be possible to get science applied to it, and to make it'more effectual than it was then. 4911. Are water cartridges used now P-Yes. 4912. Are they used in conjunction with powder or with dynamite P-That I could not say. 4913. With dynamite, I suppose P-I know they are used, but it is the exception to use them. 4914. You doubtless know that the water cartridge, as a rule, is used more in connexion with the high explosives than with powder. Were you aware of that ? -No; of course I am not so much in the collieries as I was. 4915. Then with regard to the other explosives, such as roburite, securite, carbonite, and ammonite, have they been tried in South Wales P--Only experimentally, I think. The roburite has been tried to my knowledge. 4916. You mentioned that they were not so strong as powder. Would you not say that they were rather stronger than powder ?-Do you mean roburite ? 4917. Yes, take roburite P-No. 4918. You think not P-The experienced men say that it is not nearly so effectual. 4919. Do you not know that in using roburite they have a smaller hole than in using powder, and that they use a smaller cartridge P-That I did not know, but I know that the men have been trying it for weeks at my suggestion at the Plymouth Collieries in Merthyr, and they gave it up; in fact, they could not go on. 4920. Was that in consequence of the strength or the fumes P-The strength more especially. 4921. It was not strong enough P-That is it. 4922. They could mend that by using more of it, could they not P-Well, that would mean that it would have been much more expensive. I will go so far as to say that it would be 200 per cent. more expensive. Mr. D. Morgan. FROM COAL DUST IN MINES: 4923. It starts by being twice as expensive as gunpowder, as you know P-Yes. 4924. Therefore, if you have to use more of it, it would be very much higher in working cost ?-Yes. n 4925. I think you answered the Chairman to the effect that you did not think coal dust by itself would cause an explosion if exposed to a light ?-That was my answer. 4926. On that point you differ from Mr. Galloway? -Yes. I believe that Mr. Galloway is going to extremes. 4927. Do the miners in your country agree with you on that point generally ?P-That is my opinion, certainly. 4928. There is just one other point that I wanted to ask you about, but it hardly bears on this inquiry. You will remember that in the Act of, I think, 1872, an arrangement was made for allowing the colliers themselves to examine the mines from time to time. Is that done in your district P-Yes. 4929. How often. Is it frequently done P-Do you mean the examination by workmen ? 4930. Yes P-It is done, but I do not say that it is the rule. I believe now that the majority of the collieries in Wales have been examined by the work. men. My experience is that when we have depression in trade the men give way on that point, and they are not so minute in their examination as they are in the good times, because in the first place the colliery owners can afford to keep the colliery in a better condition in the good times than in the bad times. Then they give way. The men to some extent imagine, no doubt, that if they say the truth about what they see, they would be victimised. And I go farther and say that they have cause to be suspicious of the colliery owners and colliery managers victimising them. 4931. But apart from that, generally speaking, would you say that the examination by the colliers has been useful and beneficial P-Yes. 4932. Do they extend their observation to coal dust P -No. 4933. It is more to the general ventilation of the mine, I suppose P--Exactly. I do not know that I have heard even of a report giving any explanation as to the amount of coal dust that they had in the colliery. The witness withdrew. Mr. T. D. Isaac. Mr. THoMAs DARONWY ISAAC called and examined. 4934. (Chairman.) You are president of the Rhondda Valley Labour Association, I think P-Yes, for the present year. 4935. Have you been yourself a practical miner P-I am a miner. I was working last Wednesday in the mines. 4936. How long have you been a miner P-For nearly 30 years. 4937. And have you always worked in South Wales P -Yes. 4938. Are you well acquainted with the mines there P -Yes, I have worked in about a score of them in South Wales. 4939. You have heard the evidence of Mr. Morgan; do you agree with his evidence with regard to the danger of coal dust ?-Yes; as to the general danger of coal dust. 4940. Do you think that it can cause an explosion ? -I think it does. I think that it will explode in itself when the air is very hot in fiery mines. 4941. And you have no doubt that it will carry on an explosion P-Certainly. 4942. And therefore it is a real danger which ought to be guarded against P--Yes. 4943. Now with regard to the precautions, do you think that watering is a practicable precaution P-Yes ; as far as the travelling roads are concerned, but Mr. Morgan did not say anything about the dust which is produced in the faces. Now there is a large amount of coal dust produced in the faces by the working of the coal which it is impracticable to water. 4944. Then what precaution do you suggest might be taken to deal with that case P-I would suggest that the mine should be worked in smaller sections with a fresh current of air for each section, rather than allowing the air to travel over a large section of the colliery to be heated by the natural gases and the natural heat of the mine, and also by the friction caused in the travelling of the air. When the air is allowed to travel over a large area it becomes very hot and polluted, and when coal dust is mixed with that, I believe that it will explode even when there is no gas which could be detected by a safety lamp. 4945. Your proposal to work a mine in sections would add very materially to the cost, would it not P-Yes, in the first instance. 4946. Mr. Morgan told us that he is opposed to the use of flameless explosives because he thinks they would add to the cost and would tend to throw the collieries out of work; but your proposal would go further in that direction, would it not P-I do not know whether it would; it would of course add to the expense of altering an old well developed colliery, but when a colliery is opened upon that system it would not be so material. 4947. Is there any other precaution that you would suggest P-1 agree with Mr. Morgan about the filling away of the dust and the watering, but then there is such a large amount of dust. Every inch of the colliery, the roof and the sides and the timber, are covered with dust in very small particles. There is a patent watering tank which would throw the water all over the roof and sides and everything, and I would suggest using that in very dusty mines. 4948. Is that instead of your proposal to work the mine in sections P-No; on the main travelling roads I would suggest the use of that watering tank. MINUTES 4949. Not on the faces? - It is impracticable to water the face of the workings. 4950. Even with any kind of sprinkler P-It would be too expensive and impracticable to carry the pipes through the face of the workings. 4951. Therefore the only suggestion that you can make, besides the watering of the main roads and the carrying away of the dust from the main roads, would be to work the mine in sections P-Yes, in smaller sections than many of them are at present. 4952. Each section having a separate ventilation ?Yes, a separate current of air. 4953. In what way would that prevent the danger from coal dust P? There would still be in each section a great quantity of coal dust, would there not P-Yes. 4954. Would that not be dangerous P-Yes, it would be dangerous to a certain extent, but not so dangerous. 4955. Is your object to keep it cooler P-Yes. 4956. Is there anything else that you wish to add to No,I have nothing in parMr. Morgan's evidence P-ticular to add, except as to the blowing out of shots. My experience is, that there is generally a flame with a blown-out shot. 4957. And that, in your opinion, might lead to an explosion in a dusty mine P-Yes. 4958. But you also have no doubt that coal dust is an additional danger which ought to be guarded against P -Yes. 4959. (Sir William Lewis.) 15 OF EVIDI)ENCE. Have you seen many blown-out shots P-Yes, many. 4960. You have had some yourself, possibly P-Yes, many. 4961. What do you say is the cause of blown-out shots as a rule P-I should think, as a rule, they are due to too little powder being put into the hole. 4962. Or too little tamping P-Yes; as a rule, I believe it is owing to putting too little powder to blow out the coal... 4963. Or to blow the hard ground P-Yes. 4964. It blows out at the place of least resistance PYes. ' 4965. Did you consider that it arose from inexperience when you had those blown-out shotd':Y-es,, .. .. , partly. 4966. Your experience.,with respect to blown-out shots is not the same as Mr. Morgan's. You say that they generally give off flame P-I believe that the majority of them give off flame. 4967. Have you ever had a blown-out shot fire any coal dust in your experience P-No, I cannot say that I have. 4968. Or fire any gas P-Yes. 4969. Under what circumstances P-I was working with a naked light in a colliery where there was a very thick bed of rock above the coal, and there iere some crevices in the rock where blowers would come out sometimes, and when putting a shot in the coal when there was a blown-out shot those blowers would ignite. 4970. You had a concussion with the blown-out shot P -Yes. 4971. And that brought down the gas P-Yes. 4972. -And the flame of the blown-out shot ignited the gas P-Yes. 4973. And that was gas alone P-Yes. 4974. There was no connexion with coal dust in that case P-It was not a dusty mine. 4975. That was an open light colliery P-Yes. 4976. Have you had any experience of the water arrangements where they have sprays running along the intake P-Yes. 4977. And where the water is under pressure P-I have seen it at the Mardy Colliery. 4978. Do you consider that the intake is sufficiently saturated with moisture under such an arrangement so as to lay the dust in the faces P - No, I do not think so, because it loses the dampness when it has gone into the heat of the mine. 4979. You still think that that is not sufficient for the coal faces P-Yes, Mr. 4980. Then you suggested to the Chairman that the T. D. Isaac. mine should be worked in smaller sections P-Yes. 4981. Have you considered what size sections you 26 Feb. 1892. would recommend to be adopted in order to reduce the risk of accident P-I would say that a section containing about 50 miners would be a reasonable section. 4982. Then how many splits would there be in a colliery working 1,000 tons a day P-Of course in a colliery where 400 men will be working that would mean eight splits. 4983. Do you suggest that there are only 400 men down for 1,000 tons of coal a day P-That would mean about 800 men. 4984. And that would be double the number of splits P -Yes. 4985. Do you think that would be practicable PWell, on consideration, perhaps my number is rather too low, but I do believe, from my experience, that some of the mines should be worked in smaller sections. 4986. Have you ever taken the trouble to ascertain the difference in the temperature between the intake and the return in some of the larger collieries where you have worked P You say that they are very hot, and that it is with the view of keeping the air as cool as possible that you would increase the number of splits in working the collieries P-I have not tested the air by taking a thermometer down, of course. 4987. Do you think, as a practical man, that it is the heated state of the returns which is the cause of there being accidents from coal dust in the faces P-To a certain extent. 4988. Now, if that is so, could not the quantity of air passing along those faces be increased in many places; andwould not that tend to keep them cooler, better than the adoption of your plan of dividing a thousand ton colliery into 16 splits?--Well, I would not bind myself to the 16 splits now since I have thought it over, but I daresay you are aware that some collieries are working in rather large sections. 4989. It would not be fair for me to pursue this matter, if you say you have not considered fully what would be the effect upon the working of collieries of the adoption of your suggestion to reduce the size of the sections into which a colliery is divided; I suppose you mean the splits P-Yes. "4990. Have you any idea as to the volume of air which is passing through .the large collieries in your district P--I do not know; we miners do not generally go into those things scientifically. 4991. I did not know whether, if you had considered it, you had inquired into the volume of air which was really passing along the faces where you say that the watering adopted is practically of no avail P-Not in the faces. 4992. Have you had any experience of other explosives than powder ?-Yes, of dynamite. 4993. With what result P--I believe that dynamite is highly inflammable. I believe that there is a large flame with dynamite. I have seen it myself. 4994. Have you used water cartridges P-No, never. 4995. Did you find any difficulty or ally inconvenience in carrying on your operations with dynamite ? -It is very rarely that I hlave used it; but I have done so in very strong rock, especially after a blown-out shot of gunpowder. Then we put dynamite in the cracks and crevices made by the powder. 4996. Did you find any inconvenience from the fumes of dynamite P--It was rather worse than gunpowder, especially when the air was very weak, when there was no current of air to drive the smoke away. 4997. (Mr. Bainbridge.) Have I understood you rightly, the only reason why you proposed dividing a mine into more sections, was for the purpose of cooling the working face P-Yes. 4998. I suppose you would agree that there is a great difference between the kind of dust that you find in the travelling roads and the dust in the working face, is there not P-Yes, the dust which is on the travelling roads, as a rule, is very small, it has been trampled upon by the men and horses. 4999. And has been caused very much by the movement of the trams running along P-Yes. 5000. It has all to rise, in fact, before it falls P-Yes. R4 16 Mr. T. D. Isaac. 26 Feb. 1892. ROYAL COMMISSION ON EXPLUSIONS 5001. And therefore is very much finer than the dust in a working face P-Yes, I believe some of it is. 5002. Which is the most dangerous in your opinion ? -I should say the dust which is on the travelling roads. 5003. Very much more so, is it not.-Yes. 5004. Then would you not find the dust which is in the working face, as a rule, to be somewhat coarse to the touch ?-Yes. 5005. And would you not also find that the working face which you had on the Monday has quite changed its position by the Wednesday or the Thursday ?-Yes. 5006. You are constantly going forward, are you not P-When the coal has been squeezed, it is more dusty, of course. 5007. I mean it is not as though you had a travelling road which may last for 10 years; the working face changes its position, does it not, every few days PYes. 5008. It is constantly going forward P-Yes. 5009. And therefore the risk of dust in the working face is very much reduced, is it not P-Yes. 5010. Then when you come to the question of sections, you say that the reason you aim at making the mine into more sections is in order to get the air cooler. Now, take the case of a mine with 200,000 cubic feet of air, and having five splits, that would be 40,000 cubic feet in each, would it not P-Yes. 5011. If you reduce each of those splits from 40,000 cubic feet to 20,000 cubic feet, thus making 10 splits, would that not have the effect of making it rather less cooling in its power by reducing the volume; in other words, would not 20.000 cubic feet passed round a face have less effect in cooling than 40,000 cubic feet -- Yes, but it would not carry the dust so far in a small section as in a large section. 5012. Do you mean the less volume would carry less dust P-Yes. 5013. That was not your point, your point was the heat, you know ; you said that if the mine was divided into smaller sections you would have less heat in the air P-Yes, the air would be, in my opinion, not so hot, and it would not carry so much dust as a stronger current. 5014. I put it to you, if you pass round a working face 20,000 cubic feet in place of 40,000 cubic feet, you would have rather more hieat, would you not. I think probably one answer I might put for you would be that the effect of making more sections in a mine would be to reduce the length of the current P-Yes. 5015. In that way your argument, perhaps, would have some weight. Which colliery, may I ask, are you working in now ?-I am working at the Treorchy Colliery, but what I say here is not applicable to that colliery alone, but to my general experience. 5016. I quite understand that, but I put it to you that in every well laid out colliery now, whether in Wales or elsewhere, as you are doubtless aware, it is the practice to divide the mines into sections P--Yes. FROMI 5017. COAL DUST IN MINES: As far as possible ?-As far as practicable. 5018. Every colliery manager lays out a colliery now with a view, as far as possible, of cutting it up into sections ?-Yes. 5019. But you think that aight be developed still further P-l should think it might. 5020. Do you not think it possible that in some of the modern mines the division into sections is fully carried out now P-Well, yes. 5021. Then I take it that you differ from Mr. Morgan not only with regard to the blown-out shots, but with regard to the coal dust sometimes causing an explosion itself without gas P-I believe it would, because, I have experienced it myself, especially when going on a main travelling road after a train of coal, when I have noticed the dust in the gauze of my lamp igniting, something similar to a slight explosion of gas. 5022. You have noticed the dust in your lamp PYes. 5023. But your experience does not go beyond your lamps with regard to that ?-No. 5024. Is it your impression that any recent explosion in Wales, say any explosion within the last 10 years, has been caused by coal dust alone ?-No, I cannot say that that is my experience. 5025. You have no colliery n your mind where that has been the case P?-I believe that it added to the destruction caused by the explosion at Mardy Colliery, where it was found that the explosion was carried from one district to the other with the current of air. 5026. is the mine you are now working a mine ?-It is rather dusty. dusty 5027. Do you take precautions to wet the dust P-Yes, the dust is watered on the main travelling roads and filled off. 5028. I would like to ask you a few more questions about these: blown-out shots, because it is not often that we have the advantage of having an actual collier with us. Could you tell me when you had the last blownout shot ?P-I have not been using powder for the iast 10 years, not to any extent. 5029. Then you have not been subject to blown-out shots recently ?-Not recently. 50;0. Did you fird that as your experience as a collier went on you got nmore and more power to prevent blown-out shots ~-Yes, according to how near we cculd guess the amount of powder to be put into each hole 5031. It is a question of judgment ?-Yns, 5032. Formed upon past experience ?-Yes. 5033. Did you find tlhat you got fewer blown-out shots as you got older P-Yes. 5034. You did P-Yes, as you learn the nature of the ground and the strength of the explosive you (get more experience. The witness withdrew. Mr. J. Forman. Mr. JOHN FORMAN called and examined. 5035. (Chairvman.) You are the president of the Durham Miners' Association, are you not P-I am. 5036. And you have had an opportunity of studying the question of explosions in mines P-In some degree. 5037. Have you come to the opinion that coal dust plays an important part in some of these explosions PVery decidedly. 5038. Now would you explain to the Commission how, in your opinion, the presence of coal dust operates either in creating or in extending an explosion ?-Coal dust must be present in the immediate neighbourhood of a shot. 5039. Do you think that anything depends upon the quality of the coal dust P-Certainly; dry, fine coal dust. 5040. Then if there be a blown-out shot in the presence of a great quantity of coal dust what do you think the result isP?-There is more flame. I have been a stoneman many years, and I know that we sometimes have ? quantity of flame from an ordinary shot. In my opinion an ordinary strong stone shot is equally as dangerous as a blown-out shot if it is overcharged. 5041. In either case I suppose it disturbs the coal dust which is in front of it P-It requires a certain amount of concussion, of vibration of the air, to throw the fine dust into the air. 5042. But in order to make an explosion there must 1- a flame, must there not P-Yes, there must be a flame. 5043. Therefore you require a blown-out shot ?-l think that an ordinary strong shot, if it is overcharged, gives flame as well. 5044. And in either case sufficient to cause an explosion P-In either case; all that we want is flame, and in my own experience, if a shot is overcharged we are almost certain to have flame from it. 5045. Then supposing there is either an overpowdered shot or a blown-out sh )t giving flame, and that, this ignites the coal dust in the immediate vicinity, what happens then ; how is the explosion carried on P MINUTES -Then the particles of coal dust, if finely divided and surrounded with air, ignite each other and generally extend, and the temperature rises. It is my candid opinion that the temperature rises until the temperature is such that coal dust will explode. If it is not digressing, I would explain that tlere is a certain temperature required to explode coal dust by itself. The people who are against the coal dust theory do admit that it inflames. I have talked to many mining engineers, to a large number in our county; we have talked the thing over many a time, as we are meeting every day on business, and they admit that it inflames. So the only point between us is will the temperature rise until coal dust will explode right away ? Now I may say that I have tried that on a very small scale. One night when I went home from the Seaham Colliery I took some of the curve dust home with me, and I had a very bright kitchen fire, and put everyone out of the kitchen; and I had two long rods, about 6 feet long, and put about a quarter of a pound of the dust in a bag, with the mouth open; and I reached over to the fire and put it on the fire; a bright flame came out about 6 feet instantly and singed the front of my coat. You can try that experiment at any time, and you will find that I have correctly stated the result. It only wants a high temperature to explode it, that is my opinion. 5046. Then I think your idea is that the first effect of the shot is to disturb the coal dust and ignite it ?Yes. 5047. And then the heat gets up and an explosion follows ?-Yes, the temperature rises to such a height that it explodes. 5048. And that explosion may be carried on for any distance P-As long as ever there is any dust in the air to feed the flame, it continues. 5049. Do you think that a quantity of coal dust in the air in the ordinary working of a pit is sufficient to explode P-No. 5050. It must be raised from the ground P-It must be raised by a shot, and there must be a large quantity of fine dust adhering to the sides, and the timbers and the floor; there must be a quantity of dust floating in the air before it will ignite. I have tried it myself. I was 15 years a deputy overman in the mine, and I have many a time taken notice with my light when I have been coming out in a non-fiery mine. 5051. (Mr. Bainbridge.) Which mine P-In Pease's West Collieries. A small quantity of dust floating in the air will not have any effect. There is another thing, it flies in a horizontal direction. In my opinion that is quite altered by the concussion of a shot. I believe it gets an altered motion, and that the motion which seems to give an impetus to the inflammation of the dust is quite different from the dust flying horizontally in the air. 5052. (Chairman.) Does the explosion follow the current of the air or go against it ?- might put it this way. If you ignite coal dust near the shaft it will go with the air if it is inbye; if it is in the return or outbye it will go against the air. We have experience of coal dust going both with the air and against it. It depends upon where the location of the ignition is and the track of coal dust. 5053. You have had practical experience connected with several great explosions in your neighbourhood, have you not P-In the case of the Seaham explosion I was there for 12 mionths as an explorer. The late Marquis of Londonderry sent me this letter, if you will be kind enough to read it (handing in letter). I was there 12 months, and was almost every day down the pit. 5054. It appears from this letter that you undertook 17 OF EVIDENCE. the work of exploration afterwards or represented the Miners' Association P-The explosion happened early in the morning and I went down that night, and I was there for about 12 months until the last body was found. I might say that the first night I was down I got afterdamped. We got into what were called the Maudlin Stables. Mr. Stratton, the manager, cautioned me that I was rather rash. I thought I heard a noise and I thought it might be somebody alive. I went then -to the stables aild I got carbonic oxide or else after-damp, and my head turned all dizzy and I lost a good deal of my energy. AMr. Tait, a mining engineer, said to me, "I will assist 0:ou, itis affectingyou." " Yes," said I, and so he took me up by the belt and we were all affected more or less, Mr. Stratton, the manager, was jE 82480, very much affected. I was obliged to go home, and I was not down again for two nights. That was on the Wednesday night, and on the Thursday and the Friday I was obliged to stay at home, I was so unwell, and then I returrned there on the Saturday again. 5055. Therefore you were there so soon fter the explosion that yu had every opportunity of seeing the state of the mine ?-Yes. 5056. To what do you attribute that explosion PTo Brown and Simpson's shot. 5057. That is to a blown-out shot P-No, it was not a blown-out shot. 5058. An ordinary shot P-An ordinary shot in the stone. They were widening a refuge hole. 5059. Was it a gas explosion P-No, a dust explosion; there was no gas; there could not be any gas there; it was only about 150 yards from the shaft. 5060. Your reason for saying that there could not be any gas is that the ventilation would prevent it PThere were 320,0C0 feet a minute coming down that shaft, a current of air in which no gas could possibly exist. 5061. Do you think it was wholly a coal-dust explosion P-Yes. 5062. The explosion you are speaking of occurred in 1880, did it not P--Yes; there was also one at Seaham in 1871, and if you will permit me I will draw your attention to that. That was an explosion near about the same place in that stone drift. The late Mr. Crawford himself went down and examined the mine. You will remember that he was a member of Parliament for one of the Durham divisions. He went down himself, and I was his colleague. He was a capital pitman, and he was a man who had a lot of tact about him. He said to me, " John, I never was so much puzzled in my life; here is an explosion happening at Seaham Colliery, "and I find there is no force exhibited for about a " hundred yards up to the man at the engine, and then " the indications all seem inbye over." Ie had no idea of coal dust at that time, not the slightest, and he was at a loss to account for it, he could not imagine how the pit could explode. 5063. But your opinion is now, with your present experience, that that also was a coalodust explosion?Yes; and I will give you my reason why I think so. In 1876, I think it was, I read Mr. Galloway's book on coal dust, and it occurred to my mind that that explosion might have something to do with coal dust. So I went down to Seaham and I saw Simpson, the father. He and his son fired the shot; the son was killed; Joseph Simpson, the father, was burnt, but he got out alive. Now, I said, " Simpson, will you tell me " exactly what; happened when you fired that shot " I said, " I am afraid coal dust has got something to do " with that." " Ah, man," he said, "no small coal " ever fired a pit,"-he could not comprehend such a thing--" but I will tell you exactly how it happened." He said they commenced to drill this hole; he had his son, who was learning to be a stoneman, with him; and after he got the hole drilled he was very cold; the wind was blowing past like a hurricane, and he had a new flannel jacket in the pit that night, and he put the collar up to keep the wind off him, and the son lit the match. The father, went down to the Maudlin junction, about 40 yards down, and left the son to light the match. The father stepped across so that he could see the match burning. He saw that the engine lamp was burning bright and beautiful in his face in a straight line with him as he was standing watching the match. He said the engine man's naked light was burning, and as soon as ever the shot went off a dark red flame came down from the shot and covered him up; it went off him at once and flew into the man at the engine. Now, there were 79,000 cubic feet a minute passing that man. Mr. Crawford scarcely could believe it; and when he went down the pit he measured the air himself after the ventilation was restored, and found it to be 79,050 feet, 50 feet over. Now how on earth could gas accumulate there ? There was no gas to come down or ignite at the engine man's lamp. It could not possibly be anything but dust. 5064. Then, to continue your own experience, 1 think you had something to do with examining the pit after an explosion at Trimdon Grange P-I did not examine it, but I went down to satisfy myself as to the nature of the roads. We had two men there, Mr. Wilson and Mr. Wilkinson, as explorers, but I did not explore it. I came to the conclusion that the explosiqn occurred in (Ci Mr. J. Forman. 26 Feb. 1892. 18 Mr. J Forman. -5 Feb. 18q2. ROYAL COMMISSION ON EXPLOSIONS what was called the Headways district at Maitland's place. Mr. Wilson told me himself that he was in there and found Maitland; and there was a mining engineer there of the name of Bell, and Bell said to Mr. Wilson, "It is a flushed kitty." 'The pricker had been drawn from the hole, but the straw had been put in and the shot lit up. It was very near a goaf, and no doubt a little gas had escaped out of the goaf somehow or other to this place, and a little straw had ignited a small porticn of gas and raised the dust. In my opinion that was the cause of the explosion. Here is a very important thing: Maitland was burnt, but inbye side of Maitland there was no exhibition of force. The cloth brattice was burnt outbye side a little; and there were five men working close to him, inbye side of him, who died through after-damp, who were not singed or burnt at all. I think the coal dust had taken fire and gone away out along the Headways. 5065. Did it go far P-Yes; it went out of the Headways district right down to the shaft, and it passed what is called the ('roscut district, and then it went into the Narrowboard district. 5066. In its course might it have taken up any gas ? -I do not think so, because it was all on the intakes. I could not see where the gas could come from. But allow me to direct attention to the Croscut district. This district was damp and wet, and I think about 60 yards of the road was laid with ash ballast, but the explosion never looked at that district. 5067. The explosion did not pass there P-It never looked at it. The men all got out there-a good many alive, but some of them succumbed to the after-damp when they got near the end of the di-trict. Those who got out alive, got out before the after-damp caught them. 5068. Then will you go on to the next explosion which you examined, which was Tudhoe P-I was simply down there to view, and I made no examination. From all the information that I could glean, that explosion occurred by two stonemen firing a shot on the Sunderland engine plane, or near to the engine plane. 5069. Were the circumstances similar to those of the explosions you have previously described P-Similar. There was not one of those explosions extended beyond what we call the landings, except one down the Elemore pit,' which went a little further than the landing; they all stopped at the landing, where the dust is supposed to be scarce. 5070. In all these cases, your reason for believing that coal dust was the prime agelit is that the ventilation was so geod that you think there could not have been any gas P-There could not possibly have been any gas. 5071. Does that apply to the other collieries you have named in your proof, namely, West Stanley, Usworth, and Elemore ?P-Yes. If you will look at the plan of Usworth you will see that the explosion went inbye. A very curious thing happened there. In the Middle North the stables were rather damp, it did not pass them, it went no farther. In the district above that, what is called the Low North, which was a dry and dusty road, it went right into the face. Now the Hitch North above that again, inbye over the next branch, there was water brought out of the Narrowboard district and pumped down there into the Hitch North; and it is wonderful that the explosion scarcely interfered at all with the Hitch North, the road being damp and wet. Just above the Hitch North there is another branch which goes off, which has a double intake. If that had been a gas explosion that is the very place it would have gone into, but it never touched it, it never lookedat it; there was no dust. If we go to the outbye side, we find in going up to the shaft, a direct line into what they call the Low Lawson Way. In that way there was little or no dust, and it went off at an angle to the shaft. Then the Bramston Way, an old disused w&y, it never went into, except for a very little distance. '5072. In every case then, it seems to have followed the dust, and to have avoided the damp P-It followed the dust. 5073. And avoided the wet P-Yes. 5074. Have you considered what precautions ought to be taken against this danger P-Will you permit me to point out to you the circumstance which attends all these explosions which we consider to be dust explosions. In every one of these dust explosions there is no force FROM COAL DUST IN MINES: exhibited for about 60 to 80 or 90 yards on each side of the shot, none whatever. 5075. The explosion gathers force as it goes on PYes. The drilling gear-light articles-in all these cases is set up against the wall, and there is no force exhibited for about that distance. The pricker is a very ligHt thing'; that and the others are left standing, never stirred or touched, which shows that the ignition is simply an ignition of the particles of dust to begin with without much force. 5076. Then it gathers force as it goes on P-It gathers force. In all these cases there is no force exhibited which can be perceived at the beginning. Now, I may be wrong, but I think if it had been a gas explosion, force would have been exhibited at once, at any rate, much quicker. 5077. Then I will come now to the question I asked you. What precautions do you suggest should be taken to avoid this danger P-I think that the 12th General Rule is a very good rule, but I think that the 4th General Rule ought to be amended a little. 5078. In what way P?-It points out that there must be a report that gas is seen. Now, I think it would be well if that could be amended so as to require a report to be put on record when there is an accumulation of coal dust. There are deputies going about, and the back overmen and the overmen are travelling the mine every day, and they can see whether there is an accumulation; and I think they ought to be made to look after coal dust as well as gas. 5079. Would you require the coal dust to be removed ? -Where there is any great quantity of it, it ought to be removed, I think. I think the owner would do that himself if his attention was drawn to it. 5080. Do you think that there ought to be any systematic watering P-Yes, especially in the intake roads. 5081. It is not practicable, is it, to water the faces PNo, it is not; but I do not think there is any great Tanger in the face. If there is a special accumulation of dust and a shot is fired, or a small portion of gas is fired, there might be a danger there; but in general the working face is comparatively safe, I think. 5082. Watering, then, should be confined to the main roads ?-To the main roads, or to any special place where there is an accumulation of dust. 5083. Is any alteration of the law required P-I think the general rules are very good if properly carried out, with a little addition to General Rule 4. 5084. It only wants a little more attention to the matter on the part of managers and mine owners ?-Yes, that is all. I may say that within my own knowledge dust was at one time taken no notice of whatever. Mr. Stratton himself told me at the time of the Seahan explosion that they never took any notice of the dust. 5085. But they do now, do they not P-Yes. 5086. Do you think any alteration ought to be miiade in the system of blasting-of getting coal by explosives P? -I think these high explosives are much safter. We use roburite and tonite. I am not an authority on this matter, but they are considered much safer. I think gunpowder is very dangerous. 5087. Would you prohibit gunpowder altogether P-I would prohibit gunpowder. 5088. (Mr. Bainbridge.) When you say you would prohibit gunpowder, do you refer to the county cf Durham P-Yes. 5089. Your knowledge does not go beyond the county of Durham P-No, just the county of Durham. 5090. For instance, if you go as far as Northumberland. even in the mines which have gas there, would you prohibit gunpowder P-I think that is dangerous, but 1 am speaking of our own county. 5091. In other districts where the coal is much harder than in Durham-of course Durham is famous for having more soft coal than hard-would that not be the means of stopping the working of coal P?-I think the other explosives are just as handy in our county as powder. 5092. Are you supposing now with regard to the other explosives that they are flameless P- I am not an authority on the matter, but I suppose they are very much safer. 5093. Do you know that taking the whole number of them--and there are about eight altogether-theie MINUTES appears to be somebody who at some time or other has seen a flame from nearly all of them ?-There is a question arises there. I suppose there are chlorines in roburite and there is sometimes a scintillation, but I think it is scarcely a flame. I may *vaythat we have had an inquiry by Professor Bedson and two doctors into the facts of roburite, as the men complained about it. 5094. About the fumes ?-Yes. We had a committee formed of the mining engineers and ourselves; and the Government inspector, Mr. Bell, was in the chair. We had a quantity of shots fired, and I took particular notice of the firing of these shots, and I never could detect any flame. I think it gets the coal just as well as powder. 5095. While you are on that point will you give us the conclusions arrived at by that committee on the question of the fumes P-They found that there was nothing injurious 5096. Only unpleasant?P-It was only unpleasant; there was nothing injurious. The doctors were tv~ o very able men, Dr. Drummond and Dr. Hume. OF EVIDENCE. 19 5113. Especially those deep collieries in the east of Durham, where there is most coal dust ?-Yes; but you see if they had a record of dust, that would make everyone vigilant; and then it would be always before their minds in reporting. 5114. I take it from your knowledge of these explosions, there have been very few working miners in Durham who have had more experience than you have ? -1 think not. 5115. Have you given your evidence to-day as your own, or after conference with your council ?-.Tust my own. You cannot get working men to believe that there is much danger in coal dust. They require to have a superior intelligence to study the matter out and to look at it from every point, and you cannot get them to do that. The most intelligent people think there is some danger in it, but the others have no dread about it. 5116. You gave us several instances in your evidence to the Chairman about the effect of a damp district; have you any idea what width of dampness would be enough to arrest the force and extension of an explosion P-My opinion is that it must feed as it goes, and 5097. There is the general feeling amongst the if there is no dust to feed it, it is done at once. miners in Durham now that an explosive like roburite 5117. At once P-Yes. is safer than gunpowder, or safe in itself P-We had a lot of contention to begin with to put it down, but I 5118. A few yards would be enough ?-Yes, a few think that all quietly settled down after this committee yards. Of course, the force of the explosion may sat and made a report. extend a little further, but the flame must be done. I think it is fed the same as the gas flame, but the one is 5098. We quite, perhaps, agree that roburite is safer immensely quicker than the other. than gunpowder, but it is generally thought that it is safe by itself; that is, absolutely safe in firing where there 5119. In reference to your earlier answer to a question is gas P-I could not say absolutely. about blown-out shots, you mentioned a stone shot very often being as dangerous as an ordinary shot; of course 5099. Is it used now at Seaham P-I am sure I could you meant if it was blown out ?-No, doing its work, not say. They use roburite at Iletton, and tonite zt but if it is overcharged. South Hetton. I could not say what explosive they use at Seaham, but I believe they use roburite. 5120. (Sir William Lewis.) A strong shot ?-A strong shot. 5100. At any rate, it would be thought generally safer than gunpowder P-Yes, much safer. 5121. (Mr. Bainbridge.) So strong as to produce flameP -Yes, a concussion. There are some shots 5101. Even if you were prohibiting gunpowder, you comparatively safe; they cause a little concussion, but would not extend that prohibition to these high exthere is not sufficient dust thrown into the air to do plosives, would you P-No, certainly not. any damage. I have seen scores of shots fired of that description, side shots where there has not been a fast, 5102. So long as the people believed they were safer than gunpowder or absolutely safe. you would appro'e,, or what we call a sumping shot. There is not a larger amount of concussion with those fast shots, and of their being used P-I think some mines could not be it requires a concussion to drive the dust into the air. worked without some explosive. It takes a large amount of dust, I believe. 5103. Is there much gunpowder used in Durham now ?-In the western portions. 5122. Have you at all, in your experience in Durham, seen the effect of trying to wedge the coal down as 5104. Where there is very little gas P-Very little; compared with the effect of explosives P-Yes. in fact, no gas at all. 5123. Have you seen the effect of a feather wedge ?5105. Your prohibition would hardly apply to the mines where there is very little gunpowder used P-- There is a man of the name of Mr. Ramsay, the undermanager at the Tursdale Colliery: we were all down No. there to make an examination of roburite, and he had 5106. Take the eastern pits of Ryhope, Seaham, and the juds carved all ready to fire the shots. Now, we South Hetton, there is very little gunpowder used observed, when we had these places all ready, that there now P-None at all. There is some at Haswell, I there was coal dust all along, and we had a converthink; that is all. sation with the Government inspector as to whether it 5107. They stopped using it because of the danger ? would be safe to fire shots there. Mr. Ramsay with his -Yes. wedge wedged two or three of those juds down to see 5102. And partly because the coal is not very strong P how it acted, and it laid the juds at once in a solid piece of coal. -- Yes. Every precaution is now taken that can be taken, and while some of our important mining engi5124. What seam was that in, the iMaudlin P-I am neers will not exactly give in to the coal-dust theory, sure I could not say. yet they are very careful, extremely careful. 5125. Was it a hard coal? Yes. 5109. Now, you spoke about Rule 4. I daresay you 5126. Is the wedge used now extensively in the had in your mind that the Mines Act does provide for county of Durham P-I do not think so. precautions being taken with regard to coal dust P5127. But if it answered so well there why should Yes, but there is no rule as to the accumulation of dust. not it be used more P-It answered well, but it is very There must be a report that gas is found, but I think heavy work, I suppose. that dust is more dangerous than gas. 5128. The hammering of the wedge is so severe P 5110. You are now speaking on the question of Yes, to get in; they think that roburite is safe and reporting P-That is all; to put on record that at such they use it. a place there is an accumulation of dust. 5129. It is much easier ?-Yes. 5111. You have not forgotten that there is a clear provision made for removing coal dust before firing a 5130. 1 should like to ask you a question I asked shot P-Yes, but there is no provision made to report a witness from South Wales. You will remember or to make a record of the accumulation of dust. I the provision of the 1872 Act as to colliers examining think if there were such a provision it would do a great a mine. Is that carried out in Durham much P-Yes. deal of good. 5131. In both the east and the west P-Yes. 5112. In the absence of that provision in the Act the 5132. Does that examination extend at all to coal managers of collieries like Seaham are taking great dust P-No, just to the ventilation and the roof. care, I. suppose, to have the coal dust removed, are they not P-Yes, they are taking every care now in 5133. But it is for the purpose of seeing anything these deep fiery collieries. that the men would like to draw attention to P-They C 2 Ms-. J. Forman. 26 Feb. 1892; 20 Mr. J. Forman. 26 Feb. 1892. RO)YA COMMISSIN ()N EX'LOSION would laugh at it if you asked them to examine for coal dust. 5134. They are getting improved now-a-days P-Yes, they are. 5135. You as rather being the hliad of the men, when you are counselling them, would you advise them to report if they saw coal dust in too large quantities ? -We do not like to advise anything of that kind, because we like to keep the peace as much as possible. When you arouse the ignorant mind upon a certain thing you do not know to what extent it might go. 5136. No doubt the evidence of those cases whichl you have mentioned here, and the indications that they most likely arose f omr coal dust, have been brought before the generpl body of the men in Durham P-No. Reference has been made to coal dust, and people's opinions expressed, but there has been no general consultation. I think we thought it would not be wise to call a meeting of the men and put any theory forward and ask them to sustain it, or do anything in that direction. We thought it might make mischief. 5137. Taking your evidence generally, should I be right in summarising it by stating that your own strong personal view is that coal dust by itself is able to form an explosion without gas, and that where there is a small quantity of gas the preence of coal dust very much stimulates and increases the power and danger of an explosion P-That is so. 5138. (Sir William Lewis.) What extent of coal dust would you consider it necessary to report, if it was thought desirable to include dust as a thing to be reported upon in the same way as gas is reported by your deputies P-I could scarcely give you the exact quantity; but where dust is likely to accumulate so that it can be easily observed, if the accumulation is very much about the timbers or sides, and if there is a quantity on the bottom, then it should be reported. There is very little dust to be found on the face of the workings. 5139. I think you said that you did not consider it was necessary in the face; but still you must have in your mind some idea of the quantity. Suppose you were the person examining these places, and you were carrying out what you were suggesting, what amount of dust would you regard as being necessary to be reported upon P-Anything in special places that seems to be a greater accumulation of dust than is found in the ordinary working faces, I say should be reported on. 5140. But would it not be better, instead of reporting it, to take means of removing it as far as possible, or of laying the dust with water P--You see there are so many things passed over; a man going about to examine for gas is not examining for dust, and no doubt if those places were watered they would be all right; but they do not water the face. 5141. Have you any means of watering in your collieries in Durham P-Yes, there are means of watering, but I do not think any faces are watered. 5142. I think you have just stated that you do not consider any accumulation in the faces to be attended with danger P-No, except in special places. We will suppose there is work going on in this direction (illustrating), and down here there is an engine plane working round to the shaft; the air comes in here, and at this place there might be an accumulation of dust; and there might arise a small ignition of gas, and a blown-out shot might raise a cloud of dust here, and take it right on to the engine plane. 5143. Are you speaking of a working place PYJes. 5144. If you were using explosives in the working place, is it not incumbent on someone or other to examine that place before the firing of the shot, both as regards gas and also as regards dust P-I am not sure as regards dust that that is examined for. $145. Is it not " If the place where a shot is to " be fired is dry and dus&t then the shot shall not be " fired unless one of the following conditions is ob" served, that is to say, (1) unless the place of firing and " all contiguous accessible places within a radius of 20 , yards therefrom are at the time of firing in a wet " state from thorough watering, or other treatment " equivalent to watering, in all parts where dust is " lodged, whether roof, floor, or sides; "--I ant readiug now an extract from the Act-" and (2) in the case of " places where watering would injure the roof or floor, FROM C()OAL )DUST IN MINES " unless the explosive is so used with water or other " contrivance as to prevent it from inflaming gas or " dust, or is of such a nature that it cannot inflame gas " or dust." If those provisions are carried out in connexion with all shot-firing in collieries where safety lamps are used, is it necessary to make any such report as you suggest as to dustP--I think so, because we might imagine a case happening without a shot being fired. We will suppose it is a working place, and through some defective lamp a small body of gas gets exploded. You see the dust is there5146. We are dealing first of all with shots, with the effect of shot-firing in places where there is dust P--That may be, but 1 (I not think it is carried out in the do face. 5147. Then you are assuming that this rule is not strictly carried out P-I think in the face it is not, there is no examination made. I have been a deputy myself, and I know there is no examination made in the working faces. 5148. You are speaking of your own district, of course P--That is so. 5149. And therefore I infer from your answers that these provisions are not strictly carried out. Then I think you said to Mr. Bainbridge that wherever the dust is it requires a large amount of dust to produce an explosion P-I think so. 5150. Have you followed the experiments in different parts of the country with respect to coal dust P-I have read about them. 5151. Has your attention been called to the experiments at Chesterfield ?-Yes. 5152. Have you any explanation to give as to how the committee failed to obtain an explosion in the absence of gas P--I may say, before I answer that question, that I was invited to Garsford Hall at the experiments by the Accidents in Mines Commission, and Professor Abel at that time, now Sir Frederick Abel, took great interest in me and showed me all the experiments. Then I was invited down to Harton Colliery, under Mr. Lindsay Wood, and saw the experiments there; and I have read about the Chesterfield experiments. I think all these experiments were upon too small a scale. I think it was Dr. Woollaston, a Mr. Tennant, and Sir Humphrey Davy who proved that even gas with a proper quantity of air in it would not explode in a narrow tube, and I think that the same law is obeyed with regard to the dust. I think the apparatus was far too small. 5153. They produced an inflammation, not an explosion, and the distinction which I wish to draw your attention to is between an inflammation of dust and an explosion; and I ask whether it is not possible that some of the explosions which you attribute to dust may not be attributable to the particular shots relieviing gas, and by that means produce an explosion P-I could not possibly conceive where any gas could come from in the Seaham explosion; I examined every yard of that intake-I was there a year-and there was nothing that could be found wrong. 5154. Do you suggest that it is impossible that gas may not be lying in the tadjoining strata, and that the effect of a shot might be to relieve that gas and bring it down into the intake P-I think not in our county. There are no strata in that condition in our county; it is all solid. 5155. Have you never experienced gas in rock P-I have not; in our county we cannot conceive anything being in the roof. 156. Then in your experience you have never known gas na :he rock P-I have never known gas in the rock, I have had no experience of it. You asked me about the Chesterfield experiments. I say that I think the concussion of a amall horse-pistol was a very weak concussion; when they fired two horse-pistols they got a flame. 5157. That was not what they found .- I think so. 5158. It is only fair to tell you that I am referring to an answer that was given here, and that I have the report in my hand. I think it will be found that your memory is defective on that point. Have you any suggestions to make to the Commission as to the further experiments necessary to set this matter at rest P Do you consider, as you have stated, that all previous experiments have been on too small a scale P-I think this Commission ought to make experiments to prove INUTES (W V14I,'N the thing. I think they will find that coal dust is a dangerous agent, and I think that the Commission ought to settle the question. 5159. Now, as an experienced man, what dimensions of gallery, and what length, do you think would be sufficient to place this question beyond a doubt P-I think that you ought not to have the gallery less than a quarter of a mile long. For this reason, that the ignition takes place first, and then you will see how the force increases and its momentum. In all these trials with their various apparatus they only go the length of the inflammation; they never go to the point where coal dust becomes explosive with the high temperature. I think that is an omission in all of them. I think if you had a gallery a quarter of a mile long, you would be able to ascertain the effect after the ignition, and after the force arises. I have sometimes thought that the high temperature raises gas. There is very dense gas with great heat, called olefiant gas. I believe this gas is generated, and that is the ultimatum of the explosion. 5160. What sized gallery would you suggest P-Not less than 50 feet, because the intakes are generally about 54,feet; say from 50 feet to 60 feet. 5161. Then as nearly as possible, you would endeavour to introduce the same conditions as exist in an underground mine ?-Yes. 5162. Have you considered how that could be carried outP--I think an artificial gallery built at bank is the best thing; then you are clear there of gas. I think this Government is entitled to great credit for appointing this Commission. It is a serious matter. In my readings of the history of explosions, I have come to this opinion, that a tremendous amount of damage has been done by coal dust, and lives lost in consequence. 5163. You do not think experiments could be carried on in some disused mine ?-They might be carried on there, but they would not be so satisfactory. If you were clear of gas entirely, I think that would be most satisfactory; no one would then be able to say, " how " do you know there was no gas there P," and so on. 5164. Is there much difference of opinion among the working men in your district as to the effects of coal dust ?-There is scarcely any opinion about it among DENCE. 21 the common run of working men; they cannot see it. The more intelligent of them think th aere is a danger. .165. But the greater number do not believe in it ?It is only just within these last few years that our ining engineers have been conming to it. 5166. I wanted to have an answer with respect to the workmen in general. Are they still under the beliet that there is no danger attendant upon firing shots in dry and dusty mines P-You see they scarcely have any beliel' eiIter one way or the other; they never think aboui it. I believe. 516 7. (Mr. Bainbridge.) Are you acquainted with the appai tus which is being fixed just now on the Tyne by a committee formed in Newcastle ?---I have heard that such an apparatus is now in operation at Hebburn Colliery. 5168. It is being made now ?-Yes. 5169. Have you heard what are the dimensions of the gallery which is being made P-No, I have not. 5170. As a matter of fact the tube they are putting up is about 3 feet diameter P-That is too small 5171. You think that would be too small ?-It is too small to try coal dust experiments in, but it may be large enough for proving the explosives. 5172. Will you say precisely why you think it is too smali for the coal dust P--Because I think there ought to be room for the expansion of the dust, and for the motion. 5173. It is not a very confined space.-3 feet P-No, ut that is vastly different from our ordinary roads and haulage roads, which are 50 or 60 feet. 5174. (Sir William Lewtis.) Do you think people will not believe at all as to the results, unless you have practically the same conditions as are in an underground mine P-I think it would be most satisfactory to have the conditions as near to those of an underground mine as you can get them. 5175. (Mr. Bainbridge.) I will put it rather in another way. Supposing the experiments at Hebburn Colliery on the Tyne with a 3 feet tube show the danger of coal dust as clearly as you have it in your mind, then it would not be necessary, would it, to make the experiments on a larger scale P-So far as I am concerned, it would not. Mr. J. Forman. 26 Feb. 1892 The witness withdrew. Mr. SAMUEL WOODS called and examined. 5176. (Chairman.) You are president of the Lancashire Miners' Federation, I think P-I am. 5177. How many members have you ?-42,000. 5178. You are also vice-president of the Miners' Federation of Great Britain P-Yes. 5179. With a membership of how many P-About 178,00. 5180. Have you a practical acquaintance with coal mining ?-Yes. 5181. Where did you gain your experience?P-In Lancashire. 5182. Have you worked for long there ?-About 22 years in the mine. I went in when I was seven years of age. 5183. Has your attention been called to the question of coal dust as an element in explosions P-It never was called to it in connexion with the explosions until recently, though I have been quite conversant with the action of dust in coal mines all my life. 5184. What opinion have you formed on the subject P -My opinion is that it may act es an auxiliary or an intensifier upon an originated explosion. 5185. Do you ih nk it can initiate an explosion ?Certainly not. 5186. What are the grounds for that opinion P-In the days of my mining life I have been in all kinds of mines, the most dusty mines imaginable, where gunpowder was used ad libitum, and yet I never saw the slightest trace or daniger of an explosion arising from dust. 5187. Have you read any account of the experiments which have been made ?-Yes, I have read Mr. Hall's experiments and others of the witnesses who have given evidence before this Commission. 5188. What is your general answer to their arguments, which go to show that a blown-out shot may start an explosion if there is coal dust present P--I do not think that there is any analogy between the position of the experiments and the position of a coal mine. 5189. Are you acquainted with the history of the explosions in the Durham district at the Seaham mine and others ?-Only by reading the reports. 5190. We have had. evidence to-day, for instance, from one of the officials of the federation in the north to the effect that in the Seaham explosion the ventilation was so good that it was absolutely impossible to suppose that there was any gas at the time of the explosion, yet a very dangerous explosion took place P-Of course we have had the same experience in our Lancashire collieries during the last 20 years in a very remarkable way. It so happens that where we have had the most fierce explosions it has been the most ventilated. I am now speaking of the 9 feet mine, such as the Moss pits, Brynn Hall, the Queen pit, and a number of others. 5191. In those cases do you attribute the explosion entirely to gas P--Yes, I believe that the nature of the gas in the 9 feet seams is entirely different to that of most mines. I believe it is not as easily perceived with the lamp. I believe it travels with the venltilation, and is therefore more likely to escape observation, and that renders it less difficult to deal with. 5192. Do you mean that in a case in which gas was not appareiit you would still say that it probably was the cause of the explosion P-I think that in those cases the gas being not as easily observed in the Arley mines, the low mines, it has escaped the attention of those who have had to deal with it; and the mine making gas it has gone along with the ventilation, and perhaps in some cases come in contact with the naked light; in other cases it has been the result of a blown-out shot or a C3 Mr. S. Woods. 22 Mr. S. Woods. 26 Feb. 1892. ROYAL COMMISSION ON EXPLOSIONS shot by powder, and that is how the explosion has been caused, I believe. 5193. But when an explosion is caused ycu think that it may be extended by means of coal dust ?-For a short distance I should think. 5194. Have you any actual experience or knowledge on which to base your conclusions, or is it only theory ? -Yes; about 28 years ago, when I first took the part of a collier, I was working in a mine called Laffak GarsWood, near St. Helens. It was an Arley mine, and we used to fire our shots by the old process at that time, not to fuse nor by electricity, but by what we used to call the German-perhaps Mr. Bainbridge will understand what I am referring to-and there was some error in filling up the German; when I came to light it with my wire it went and I was right in front of it. Of course I remember perfectly the great blaze that there was; it was just like being in a furnace; it blew two tons of coal over my head; it must have taken it over my head; of course I cannot say how it took it; it took my lamp and my cap; it saved my life and did not blind me, though my face was right against the shot. Now that place was completely enveloped with dust, and notwithstanding the fact that there was all the blaze amounting from the shot yet there was not the slightest trace of dust being ignited. 5195. You have seen perhaps, yourself, in some of these explosions, but if not you would have read, that caked coal dust is frequently found after the explosion ? -I remember being down two mines. One was the Garswood Park Collieries in an explosion that occurred there. I commenced to work there shortly after the explosion, say within two months after the explosion, as soon as the mine had got opened. I found there, in the very place where the explosion had occurred and where men had been killed to the extent of between 20 and 30 of them, dust thrown all along, in some cases 2 inches thick, in other cases 3 inches, but I never saw the slightest trace of caked or burnt coal dust. It was unconsumed. 5196. Yes, but a negative does not prove anything, does it P That only shows that, if you are correct in this particular case coal dust was not consumed, but it would not answer those cases in which the coal dust has been found in a burnt and consumed condition ?I have read those staternents. Of course, I am rather confirmed in this opinion, because I just went through the same experience at the High Brook Collieries. I was the very first to go up the roads after the explosion there. In neither case did I see the slightest trace of burnt coal dust. I should think where there had been a terrific explosion there would have been some traces of this caked coal dust. We have had, in fact. some of the most fierce explosions that have occurred in any county in the country. I should think everybody will agree that the Lancashire explosions have been such. I am rather suspicious, therefore, in my own mind as to whether that is an accurate statement or not. I its5197. Do you mean that you doubtit, though I as to existence P-I have never seen the evidence have been in these positions myself; and I think if it had been possible for such to have taken place that I should have seen it either in one colliery or in the other, because in both cases they were dusty mines. 1 have got the plans of the two mines here, but perhaps you will not require them. 5198. I think not. It is not i question of the plan; it is a question of the fact of the caking ?-This was in the Arley mines, and everybody knows the Wigan Arley mines are very dusty, mines. That would be before Mr. Hall's inspectorate. 5199. (Sir William Lewis.) Mr. Dickinson would be there then P-I think Mr. Higson was the inspector. 5200. (Mr. Bainbridge.) It was a long time ago ?Yes, that would be in 1867. 5201. (Chairman.) What is your conclusion then on the whole question. Do you believe that all explosions are due to fire-damp P-I do. 5202. Do you think that dust plays any part in the explosion ?--Only on very exceptional occasions. 5203. Then under those circumstances do you consider that any further precautions are necessary against dust ?-There are two precautions that I think ought to be taken. One is that shot firing ought to be abolished in coal mines. I think that wherever you have coal IROM COAL DUST IN MINES : mines, it does not matter what kind of explosive is used, whether it be gunpowder, roburite, tonite, dynamite, or any other of the patent explosives, you will always be in danger of explosions in coal mines which give off a large quantity of gas. 5204. How would you propose to get the coal in place of using explosives ?P-Of course a great many of the mines are being got now without-some that were formerly supposed to be impossible to get without explosives. I think the tendency of the age is to drift more in that direction than ever. 5205. What are the substitutes that you think can be employed P-In some places there is the wedge used; of course that is the old method of getting coal. I do not know anything else that could be employed unless some other invention could be adopted. 5206. With our present knowledge do you think that the wedge could be employed universally in coal mines ? -I think it could. I think we have coal being got without any kind of explosives in Lancashire to-day-as hard as any seams in the country. 5207. Would that not have the effect of very greatly increasing the cost P-It would increase it, but I do not think very greatly. 5208. Who do you think should pay the increased cost P-That would be a matter for arrangement. 5209. You would not like the men to pay it in a reduction of wages ?P-Certainly not; their wages are low enough. 5210. But would not that be a probable result. If consumers were for any reason unable to pay the increased cost it would have to come oot of somfbody's pocket, and is it not probable that it would come in part, at all events, out of the pockets of the men ?-I think it would be so infinitesimally small in time that it would not affect anybody seriously, and I certainly think that if it would have a tendency to make our mining safer it ought to be met from the public or from any other source. 5211. To-day another representative of the men has given his opinion in exactly the opposite sense; that is to say, he has said that there must be a certain amount of risk in coal mining ?-Certainly. 5212. And that if any attempt were made to get rid of that risk altogether it would destroy the trade, which would be to the injury of the working classes geerally ? -I do not think that would follow. I might say for your information that when the last Mines Act was being discussed in the House in 1887 the miners of the country had a conference in London here; and, I believe, with the exception of South Wales, that they were all agreed to advise the Government to go in for abolishing shot-firing altogether. The Southe Wales representatives were the only section of the nation that were opposed to it at that time. 5213. (Sir William Lewis.) You are speaking from experience in your own district P-Yes. 5214. Entirely P-Yes. 5215. So that you are not able to appreciate difficulties that might arise in South Wales by the abolition of the use of' powderP--Certainly I could not speak for South Wales only by imported knowledge, or knowledge given in conversation. 5216. But from your experience of using the wedge do you think it would be practicable to us a wedge for bringing down a rock top, or for driving through hard measures between seam and seam, or for taking up what is very often found in South Wales under the coal, a rock bottom P-Of course you are speaking now of the metal, not the coal. 5217. Yes; I am talking of the coal P--Of course, in that case, there might be exceptional treatment. I think that even some of the patent explosives, if under proper supervision, and at a proper time, might be carried on with perfect safety. 5218. So that you would qualify it to that extent PI would. 5219. Where would be the line that you would draw ? Would you suggest that as regards the actual getting of coal there should be no explosives, but in any roof that has to be taken down or bottom to be lifted you would allow explosives to be used; is that it P-Yes; or even L would make an exemption if it was found impossible with regard to some mines. For instance, we have mines now where it is supposed to be very MINUTES 23 OF EVIDENCE. dangerous, and where the explosives are only used at a time when all the men are out of the shaft, with the exception of the shot firers. That is a common occurrence in Lancashire, 5220. Is that not done generally throughout most districts ?-It is not throughout Lancashire. 5221. I mean where safety lamps are used. I am not speaking of open lamp collieries. I am assuming that you would not suggest to abolish powder in open light collieries, would you P-Of courbe there might be greater freedom there, but my opinion is, and I am confirmed in the opilion, that there is none safe. 5222. Neither open iight nor safety lamp P-I mean no mine safe. We had the case of the Hyde explosion; I remember sitting there for three days listening to the evidence, and that colliery had been worked for 50 years. 5223. That is to say, no mine is safe from an irruption of gasP--Certainly, only under very exceptional circumstances. It was stated there in evidenceI have got the report here-that gas had never been seen by anyone in that pit for 50 years; and yet an explosion took place and killed between 20 and 30 people-23 people, I think. 5224. You are still limiting your experience to Lancashire P-Certainly. 5225. Now you said that the extra cost would be infinitesimal P-Yes. 5226. Supposing it was something more than that, would you think it advisable to insist upon abolishing the use of powder, assuming that it would increase the cost of working, by way of illustration, say, sixpence a ton P--I certainly think that cost ought rot to stand in the way where human life is at stake. 5227. So that if it meant the shutting up of a colliery you would abolish the use of powder-I should not think that it would go so far as that. t228. No, but supposing it went so far as that. I am putting a case that if a colliery could not be carried on without some explosive, would you insist upon abolishing the use of powder to the prohibition of the working of any colliery P-If it was a very dangerous mine, and there was a danger of an explosion I should. 5229. An explosion from gas P?-Yes, certainly. 5230. Then you would limit it to collieries where there was a liability to irruption of gas P-Certainly. 5231. Have you any hard rocks in either the top or bottom in your district P-Yes, we have rock roofs and rock floors too. 5232. How do you deal with them? - They are generally got on the old method of working; they generally cut the stret and bring the pillar back, and they never interfere with the roof. They do not do the packing; there is not the same packing there. 5233. Then the question of being hard or otherwise does not affect the point P--Not in those collieries. 5234. No; if they have not got to take it down, the material being hard or soft does not affect the question, does it P-You are now speaking of rock roof. 5235. I am speaking of rock roof where the seams are not sufficiently thick to enable the coal to be extracted without either cutting into the rock roof or taking up the rock bottom P-I do not know that we have any rock roof of that kind. The rock roofs that I know of are where the mines are about a yard thick ; we have not anything less than that, and, of course, they work the mine without either touching the floor or the roof. 5236. Then iK does not affect the question P-Not in that case. 5237. There you have simply the coal to deal with pThat is so. 5238. And you say the coal can be obtained without the use of powder P - I- ay they can be; I do not say they are. There are explosives being used in those mines now, but I say that, in those cases it would not interfere with the rock roof or the floor, because they get the coal out and leave the roof standing and. the floor too. They work it in the yard seam. 5239. Will you assume for a moment that instead of that seam being 3 feet thick it is 2 feet thick, and that in order to get that 2 feet the roof has either to be taken down or the bottom to be taken up, and it is rock: what would you advise under such circum,- stances ?-Of course in those cases the floor would have te come up or the roof would have to come down. 5240. Then if you abolish the use of powder, how would you take that floor up or take the roof down PMy answer to that is that which I gave just now, that it would have to be blown down or taken up at times when there was not so many men in the pit, or they could use one of the supposed safe explosives. 5241. Yes, but have you anything to suggest different to what is the common practice in all coal fields now with respect to setting off shots when there are not many men in the pit P-No, I ha.e not. 5242. Are you acquainted with the provisions of the Mines Act P-Yes. 5243. You have nothing to suggest, then, by way of improvement P-The only thing that I can suggest is that I certainly agree with the inspectors, and they have given utterance to this in their reports for years, most of them, that so long as we have shot firing in our dangerous seams we shall always be liable to explosions. I certainly think that. Then in the other case, suppose that we allow that shots should be fired, then the only recommendations that I should suggest would be that the Mines Act should be carried out, that is, it should be literally carried out; there should be an adequate amount of ventilation, and our managers should see that the safety clauses of the Act are carried out, with a view of preventing accidents. 5244. But are you giving your evidence on the assumption that the Mines Act is not fairly carried out, or that it is carried out P--Of course I hold an opinion of my own that in these days the question of cost is a serious matter. I quite agree with that; it has to be made to pay, both from the employers' point of view and the workmen's, but I believe that there are exceptional cases where the Mines Act is not carried out. I do not say that that applies to the bulk of the collieries. I believe our collieries are far better managed than they used to be, and are managed efficiently; but there are exceptios to the rule in that case. Of course I have had cases come under my own notice where it has been so. 5245. Yes, but may I ask you to assume that the provisions of the Act are fairly carried out; have you, then, anything to suggest P-No, .1 think they are fairly carried out, but what I mean by that is this: that we think that there is not sufficient inspection, we think that the Act is too loosely carried out in certain ways. 5246. I am asking you, are you giving your evidence on the assumption that the provisions of the Act are not fairly carried out P-Certainly I should say they are. 5247. Now, with reference to your observations after explosions and your difficulty in believing that coke has been found in the nature of small coal charred, which was really what the Chairman put to you; you do not appear to have believed that such a thing could have occurred P-I am rather suspicious in my own mind; I would not like to say it is not so ; I could not say it is not so, but I have my own doubts about it. 5248. Did you search for gas when you have gone in after an explosion; or did you search for any other indications as to the direction in which the explosion had gone, assuming that you had discovered where it was initiated P-I searched for gas; of course all colliers do, more particularly after an explosion. 5249. And was it for gas alone that you searched PNo; we were quite conversant with the dust, working in a dusty mine; but I did not notice anything different in the mine immediately after the explosion to what I did on ordinary occasions years after. 5250. But in going along with your lamp what you naturally did was to try for gas as you went along PJust so. 5251. And you did not observe at all whether some of the timbers or the floor were covered with charred coal dust P-I never saw the slightest indication of it on either the props or the sides or the floor anywhere. The dust looked to me in its regular ordinary condition. 5252. Then you mentioned as to the difference in the gas, and that it was more difficult to observe the gas P -Yes. 5253. It may be more difficult to observe, and as we know, those who are acquainted with the Lancashire collieries, your gas is what is termed quicker P-I should think it is, C4 Mr. S. Woods. 26 Feb. 1892 24 Mr. S. Woods. -26 Feb. 1892. ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES: 5254. That is to say, it does not show an indication for such a long time before it actually explodes P-But that, of course, only applies to some mines. 5255. In the 9 feet P-In the 9 feet. 5256. I am speaking of the 9 feet at Garswood Hall ? -Yes, it applies to that. 5257. But still you do see the gas before it explodes in your lamp P-At the Brynn Hall I was well acquainted with an official there between the two explosions; there were two very soon after one another; and he told me that the mine (and, of course, I have every reason to believe it, because two colliers themselves told me the same thing) was so well ventilated and there was such a volume of air going into the mine that they actually had to work with their clothes on, and yet the gas showing such a peculiar colour as it does in the 9-feet mine, it would naturally escape observation unless it was by a very practised eye, a man that thoroughly understood the nature of the appearance of the gas. 5258. You may have had a large quantity of gas brought down by a fall of roof P--Yes, that has been so in many cases. It was so at Clifton Hall and so at Hyde, I believe. 5259. So that the mere fact of the difficulty of seeing the gas does not appear to me -I say so with great respect-to affect the point that you put to the Chairman P- It affects it in this way : in a low mine the gas is in closer proximity to the eye than it is in a mine about 7 or 8 or 9 feet high. In the latter case it is so much above the man's head that he does not look for it with the same care; it is not brought so intimately under his notice as it is in the low seams such as the yard mine and the 4-feet. 5260. With that knowledge, you say from your experience in examining places after explosions have occurred, that they must have all been due to gas, and could not have been due to either dust alone or gas and dust P-Yes, in most cases that would be so, because most of the men have died from suffocation, not from burns. For instance, that wds so at Hyde; there were 23 men killed there; there were very few of them burnt, they were suffocated. 5261. What explosion are you referring to now P What date P-The Hyde explosion. It occurred on the 18th January 1889. I have got the report of it here if you would like to see it. 5262. No, thank you. I want to know the particular date because we have had the Hyde explosion referred to before. Have you had any experience of blown-out shots ?-I have. I have had them myself. 5263. What kind of a place was that which you described to the Chairman, where the coal was blown over your head; was it an enclosed place or an open face P-I will shortly describe it. It was in the Arley Mine; it was out of the level; the first shot upbrow cutting through to the level above. We holed the coal at the top up to the roof and blew out both sides. We did not cut any of the side. I had blown one side out and, of course, freed it, and was blowing the other, and it lifted the 2 tons of coal in a solid lump right up-well, over my head it must have been, cause it was right be behind me. I do not know how it got there; of course, I was too excited. After the explosion I got out as soon as I could. It was just like being in a furnace. I have got the mark on my thumb now where it knocked my thumb, and, of course, all my breast was covered with bits of coal. It was the first shot up the brow, and it threw the coal right into the lower side, the 6-feet place ; it was from the higher side into the lower side. 5264. Was there much dust below that P--The place was full of dust; it is naturally a dusty mine. 5265. But the direction of the explosion was towards an open space. There was no concussion P--It was near to the level face, and, of course, there was the 6-feet below. 5266. It was going towards an open space P--Certainly. 5267. But there was no concussion P -Certainly; but it would be more confined than a shot in the level. 5268. It had spent itself by moving these 2 tons of coal, as you have described, just over your head, and possibly altogether not more than a couple of yards PCertainly about a couple of yards. 5269. And it spent itself in that P-Yes, of course, it naturally spent itself after the shot had blown. 5270. Do you suggest there was any gas there P-There would only be the ordinary Arley gas, 5271. You did not discover that there was any gas bIefore you fired the shot P-I do not think there was. Of course the mine made gas just as all Arley Mines do, but I do not know that there was any sufficient quantity to make us apprehensive ,f danger. 5272. Is that illustration which you have given the Chairman one of' our experiences of a blown-out shot which did not create an explosion but which set fire to the dust and continued for some distance ?That was not a blown-out shot although it blew the coal out. I have had blown-out sh ts. 5273. But take it that it blew the coal out; in your opinion if dust could create an explosion, you would have had a very different state of things under those particular circumstances, to what you did -If it had been possible in my opinion for dust to have been, say, a principal factor in an explosion, I will not say the primary cause, but the principal factor, I believe there would have been many scores of explosions in that mine. 5274. I would like you to confine yourself to that particular illustration, because I fail to understand why you should have expected that, even assuming that your theory is correct P-I do not understand you. 5275. You gave an illustration of your being in what you described as an explosion, and you said that if dust would create an explosion you would have had at that particular time a large explosion extending into the workings P-I do not say that I was in an explosion of gas, I only say that I was in the explosion of the shot. 5276. What did you expect with an explosion of a shot in a dusty place; would you have expected that the dust would have been inflamed and have created an explosion which would have continued into the workings P-I should have thought from what I saw of the large flame that was given off' by that shot that if it had been possible for dust to have ignited at all it would have ignited on that occasion. 5277. And because it did not, you do not believe that explosions can be initiated by dust ?-That is a strong reason that I hold. 5278. (Mr. Bainbridge.) You referred just now, in answering Sir William Lewis, to an occurrence which happened at the face of the mine; have you noticed the difference between the quantity and quality of dust in the face of a mine and of the dust in the travelling roads P-I have noticed that frequently. 5279. Have you observed that in the travelling roads it is very much more fine and impalpable P-Yes; that is so. 5280. And therefore more dangerous P-That is so; but I have also noticed that you have a purer kind of dust in the coal face than you have in the road. What I mean by that is, that in the roads, as a rule, you have it mixed with dust from the roof or floor, but it is much finer, because it is constantly being trampled upon. I quite agree with that. 5281. It is very much finer than the coal dust you generally find in the face, which moves forward, as you know, almost day by day, does it not P-Yes. 5282. You would hardly think it right, would you, in that case, when you consider that the coal dust in the face is so much more oarse than the coal dust in the oe travelling roads, to take an incident which happened at the face to form your judgment upon with regard to coal dust generally P--My inference would be this: As far as I have been able to observe, most explosions have originated at the coal face. I am not saying there are not exceptions to that; I know there are, but most explosions occur in the coal face, and, that being so, if dust would have a tendency to ignite at all, it would be the kind that is lying about the coal face, because the blaze is spent altogether before it gets very far into the travelling roads. 5283. You know there are a good many people who think there have been within the last 10 or 20 years a number of explosions caused by coal dust, do you not P -Yes, I know that. 5281. I know you disagree with that opinion; your evidence is very plain upon that point; but surely you know also that those occurrences of explosions which are said to have been caused by coal dust have hardly happened in the face at all; can you tell me by a single case where the explosion which has been described as happening from coal dust has occurred at the coal face ? -- I was taking the theory as applying to all explo. sions, MINUTES OF EVIDENCE. 5285. I know you are; but I am asking you -whether in your knowledge of the explosions which have happend within the last 10 years you ca-n call to mind a single instance of a so-called coal-dust explosion which has happened at the working face -- The Hyde explosion is supposed to have happened at the coal face. 5286. But you say that at Hyde the gas came down from the rootP--Yes, I believe it did come down from the roof. 5287. So that could not have been coal dust ?-No, it was gas from the roof. 5288. I ask you whether you know of a single case of a so-called coal-dust explosion which happened in the face P-No; I think Mr. Hall has inferred that a great many of the Lancashire colliery explosions have been brought about either directly or indirectly through coal dust. Now, a great many of those explosions have occurred in the coal face, I believe, either through blown-out shots or a reckless use of gunpowder. 5289. Do you carry one case in your mind; can you mention one case P-I think I can. I think the explosion at the High Brook Colliery on the 23rd of January 1886 is supposed to have fired at the coal face. Then the High Brook Colliery explosion on April 1st, 1869. Then there was the Garswood Park Colliery (in the little Delf) on the 4th of March 1886; and there was also another explosion at the same colliery. 5290. Were these all at the face P-Yes; they are all supposed to have. been caused through blown-out shots. 5291. And coal dust P-As a rule there has been coal dust in the mine; of course I am not assuming that it can have happened through coal dust at all. I think the evidence has proved that it is through gas, and the juries' verdicts, after listening to the evidence, are, that these have been purely explosions through gas. Of course I know that the dust theory is a modern one; I am quite aware of that. 5292. I am sure we have your view very clearly expressed, that you do not think that coal dust will initiate an explosion P-I do not think so. 5293. And I think you go a little further than that, and say it is not a very serious thing in carrying it on P -I say this: it would only be in exceptional cases, in my judgment, where it would ignite coal dust. That would more probably be in the road in the case of an explosion taking place, on a travelling road or some. thing of that kind. 5294. But you think an exulosion of the gas must take place first P-I do. 5295. And even after an explosion of gas has taken place, it is only in an exceptional case where that explosion can be imparted to coal dust ?-I think so. 5296. In that case, would you consider that the provisions of the Mines Act (which are rather important), as regards the coal dust, are unnecessary ?-With regard to the watering, do you mean ? 5297. Yes P-No; I think it is a great advantage, although of course it has its disadvantages as well as advantages. From the standpoint of preventing explosions, where it can be done, it is a very good provision. 5298. It is a safeguard ?-Certainly. 5299. And then there is the sanitary advantage PYes, it is better from the sanitary point of view. It is much pleasanter to work where the mine is watered, and I certal iy think for this purpose, under any circumstances, and if an explosion might take place, watering would prevent the liability to that. 5300. I should like to ask you a question with regard to the Mines Act not being kept to in your district. I suppose if there had been any violation of the Mines Act, which had come before you as representing the men, we should certainly have heard of it through the Employers' Liability Act, should we not P-Yes; but perhaps I ought to explain what I mean by that. Where there are mines giving off gas, and the employers, after being cautioned by the inspector, still continue to use naked lights, I consider that is a reckless carrying out of the Mines Act. We have had instances of that. 5301. Does not that generally-lead to arbitration P-That has been so. My opinion may be wrong, but if there is a danger there is a greater guarantee against explosions where it is watered; that is my opinion. E 82480. 2{\ 5302. I regard you as an important witness, representing, as you say, 178,000 men. May I take it from you, that you think there is no variation required in the Mines Act to render explosions less frequent ?--01 course I am only speaking so far as dust is concerned. You know we do think there should be an alteration, because -we have a Bill before the House now dealing with other aspects of the question. What I think is, that the first general rule should be carried out strictly, and that due precautions should be taken with the explosives, because I do not think we shall ever be safe so long as any explosive is used, for I believe they are all liable to ignite gas. Therefore, what I think is, we have the first general rule saying that there must be an adequate amount of ventilation produced to render gases harmless, and if that is rigidly carried out and sufficient precautions are taken with regard to the shot-firing clauses and the watering, if there is any danger from that, I do not see what other remedy we could suggest. 5303. Then with regard to shot-firing you think that if all the precautions of the present Mines Act are strictly adhered to there would not be a serious danger in carrying on shot-firing P-There would not be so much as there is, I think. 5304. If the Mines Act was strictly adhered to with regard to the shot-firing question P-Yes. Of course, I ought to qualify that by this: We are all very pleased to see the diminution in explosions which has taken place, as a result of mining legislation I believe, and explosions now are of very rare occurrence. Of course, to make mines still more safe, it is very difficult to suggest a further remedy than those already provided. But you will have observed, as well as I, that most of the inspectors give it as their opinion that so long as shot-firing is allowed-and, of course, I speak with considerable experience, having had 20 years in a minewe shall always be subject to mishaps from some unforeseen circumstance arising. I believe we should be safer if shot-firing were done away with altogether. I believe that naked lights are almost the only causes of explosions. 5305. (Sir William Lewis.) That is from a gas point of view ?-Yes; of course I do not believe so very much in the other. 5306. (Mr. Bainbridge.) May not you carry that rather too far. I am sure we all quite agree that it is very important to reduce the number of explosions and of every sort of accident in a mine ; but as to the argument you put forward now, as you know, there are a great many accidents caused by falls of roof P-Yes, certainly. 5307. Now, if there was an Act passed requiring timbers in the mine to be placed twice as close to each other as they are now, that would reduce the falls of roof, would it not P-Yes, and it would reduce iomething else. 5308. It might reduce the profit P-It might reduce the production. 5309. You can quite see that carrying on the idea of stopping shot-firing altogether might, as we have heard from a witness this morning, be a very serious thing in some districts, though it might not be in yours P-It would to some extent in ours I quite agree, but if it was applied generally I do not think, after it had been in operation like any other reform, that after a time it would be the serious loss which is anticipated. It might be for a time, and in some seams it would come very heavy, in the hard seams, the low seams. 5310. Which do you call the hard seams, where gunpowder seems so important ?-The 9-foot is the hardest, the big mines as a rule are the hardest seams to get. 5311. In the case of an explosion like the Seaham explosion, where everybody appears to be agreed that there could not possibly have been any gas at the point where the explosion took place, how do you account for that explosion P-I hold the opinion that there must have been gas. I do not say that gas was seen or known of, but there must have been gas, in my opinion. 5312. You think that those parties who have, after so full an inquiry, come to the conclusion that there was nu gas must have been mistaken ?-The jury, do you mean. 5313. No; I mean the experts who have made the examination ? - The jury did not come to that verdict. 5314. I was not saying a word about the jury. I was asking about the experts who made the examination PIt is just possible that they might err, they are as D S. Woods, Feb. 1892. -6 26 Mr. S. Woods. ROYAL COMMISSION ON EXPLOSIONS liable to err as any one else. It is a matter of opinion, I suppose. I know the late Mr. Picard held that it was gas. 26 Feb. 1892. 5315. When you were speaking about the use of a wedge in your district, were you referring to the short wedge or the long wedge-you know there is a wedge about that length (illustrating), were you referring to that ?-I think I included that by my reference to any other invention which might be suggested. I meant any patent wedge. There are patent wedges now which are used in some mines. 5316. In Lancashire ?-I do not think there are in Lancashire, but there are in some other counties-I believe in Yorkshire. 5317. But you know, as a rule, that although a wedge would be by far the best thing to have--PYes. 5318. So far it has made very little progress P-Yes, the patent wedge. 5319. Owing probably to the severe manual labour required P-The shot-firing process has rendered it unnecessary almost. It would be more common in the early days of mining than it is now. 5320. I think you spoke just now rather against the idea of high explosives having proved safe, is that so P -Yes. 5321. I suppose it is in Lancashire where roburite has been more used than anywhere P-Yes, but we have an inquiry, now adjourned, on this question where a man is said to have been poisoned through it. 5322. (Sir William Lewis.) Poisoned ? - Well, the doctor's evidence is to that effect. 5323. (Mr. Bainbridge.) Are you now speaking of the after fumes P-Yes. At the time roburite was introduced into Lancashire, that would be about three years ago, there was a big strike for three weeks about it, and I think a member of the Commission was one FROM COAL DUST IN MINES: of the experts called in, who was the public analyst, agreed on by myself on the one side, and the coal proprietor on the other, to inquire into it and bring about a settlement. The report that he made, with the joint medical men, was that it certainly was not fit for anyone to live amongst, the gas was most deadly. 5324. That is so far as the fumes are concerned ?Yes. I was going to say, with regard to the light, that when it was first introduced the Geological Society of AManchester held several meetings, experimenting with it, and they experimented with it in the different collieries. I can produce the '"Wigan Observer," giving the results of their experiments, stating that they had seen a glare from it, and I think there have been cases where it has actually ignited gas. There. fore I do not think that any of the explosives are safe. They are safer, considerably safer, perhaps, than powder, but where there is a large body of gas I am afraid we shall always be in danger of an explosion from any of them. 5325. Speaking generally of these higher explosives, you do not go further than to say that whilst you do not consider any of them safe you do think they are, on the whole, safer than gunpowder P--I do; but they are less applicable to do the work. 5326. (Sir William Lewis.) I think you said that you represented 178,000 workmen ?--I am the vice-president of an association which has that number. 5327. In the views you have expressed here is the Commission to take it that you represent the 178,000 workmen P-What I say on that point is this, that of course I could not put that before 178,000 men, but froMn my general knowledge only of opinions expressed in conference, in public meetings, and in other places, over 90 per cent. of the men would hold the opinion that dust could not originate an explosion. 5328. But this question has never been submitted as a question for the men to give an expression of opinion upon ?P-Only by way of resolutions at public meetings. The witness withdrew. Adjourned to Friday 4th March next, at 12 o'clock. At 23, Great George Street, Westminster. FOURTEENTH DAY. Friday, March 4, 1892. PRESENT: TH RIGHT HON. JOSEPH CHAMBERLAIN, M.P., CHAIRMAN. Mr. CHARLES FENWICK, M.P. LoRD RAYLEIGH. Sir WILLIAM LEwIs. Mr. EMERSON BAINBRIDGE. Mr. J. WILSON, Secretary. Mr. I. W. Martin. 4 Mar. 1892. M r. HENRY WILLIAM MARTIN called and examined. 5329. (Chairman.) You are a mining engineer P-I am. 5330. Vice-president of the South Wales Institute of Engineers P-I am. 5331. And a member of the Monmouthshire South Wales Coal Association, and general manager for the Dowlais Iron Company's collieries of South Wales ?-I am. 5332. What was the output last year ?-1,034,775 tons. 5333. You have had a large experience in the management of collieries and ironstone mines ?-I have had over 30 years. 5334. In what districts ?--In the Aberdare district and the Merthyr district; also in the Durham district, and in Japan. 5335. What is the class of coals which are worked in the Dowlais collieries ?-Steam coals and bituminous coals. 5336. Are the mines what are called dusty mines PThey are not. 5337. How are they worked, what safety lamps are used P-The Evan Thomas' Bonnetted Clanny in some collieries; in other collieries we work with naked lights. 5338. Is shot-firing employed P-Very largely. 5339. Can you state what is the average number of shots fired ?-We fire upon an average 383 to 400 shots a day. 5340. Are these mines subject to fire-damp ?-Yes, all except the bituminous collieries; in the bituminous MINUTES OF EVIDENCE. collieries we have not had any gas, we have never seen any gas in them. 5341. When you say that naked lights are used, do you mean that those are used in collieries in which there is fire-damp P-Yes. 5342. Is that in the steam coal collieries ?-In the steam coal collieries. 5343. Have any explosions occurred in those collieries ? -Yes, several-slight ones. 5344. Have any explosions occurred in the bituminous collieries ?-None whatever. 5345. And your observation as to the mines not being dusty applies to both classes of mines P-Yes. 5346. Now, has your attention been directed to the question of the importance of coal dust as an. agent in causing explosions P-It has. 5347. What is your view as to the danger of coal dust in mines P-I think that coal dust aggravates explosions initiated by explosions of fire-damp. 5348. That is to say that when any explosion has been initiated by fire-damp you think that coal dust may increase its danger and extend it P-Undoubtedly. 5349. Do you think that the presence of coal dust makes an explosion of fire-damp more probable; does it increase the liability to explosion P-Yes. 5350. Do you think that coal dust alone in the absence of fire-damp would cause an explosion P-No, not as we see it in the general working of collieries. Under the ordinary conctitions of working a mine I do not think that it would. 5351. What is the method of working the thin seams of coal in South Wales P-By long wall, but there is a great deal of roof ripping and bottom cutting. 5352. Does that produce much dust ?-Yes, shale dust, stone dust. 5353. What is the effect then of the production of that class of dust in those mines P-I think that it renders the coal dust less liable to burn or inflame. 5354. Does that account in your opinion for the non. liability to explosion from dust in Welsh mines PPartly, but I consider the damping of the dust to be the chief means of preventing the extension of explosions. 5355. I suppose that the quality of the coal dust differs in different mines P-I believe so. 5356. And that some might be expected to be more explosive than others P-MIore inflammable than others. 5357. Have there been any experiments in your experience which show this P?-I took great interest in the experiments made by Mr. Galloway some years ago, about 1885 and 1886 I think. He made some experiments at Dowlais and I took great interest in watching those. 5358. What was the effect of his experiments P-They have been reported; but what struck me regarding the difference in the dust was, that when he had not dust in 'those experiments obtained from collieries in the Rhondda Valley the experiments were delayed; the dusts supplied to him from collieries in the neighbourhood waere not suitable for his experiments. 5359. They failed to explode P-So far as I could see they failed to explode, and in fact he would not use them. The dust he obtained from other collieries was the very finest, and it was specially dried, and then fanned up with a mixture of gas. 5360. In those cases, and under those circumstances, which you consider exceptional, he secured explosions ?P -Yes. 5361. Now, do you consider that the colliery explosions of which you have any knowledge have been caused by fire-damp alone P-I do. 5362. What explosion would you give as an illustration of that P--Ivy chief experience is with fire-damp explosions; but I saw a mine after an explosion in the Pochin pit at Tredegar. 5363. What were the circumstances of that explosion ?-At the inquiry they did not come to any full settlement how it originated. The inspectors of mines did not agree with the evidence given by the experts, and the manager of the mine did not give any opinion at all. But I think that the explosion was initiated by fire-damp alone, and was aggravated and extended by dust. 27 5364. I take it, then, that in your opinion, coal dust Mr. is only to be considered as extending an explosion P- H. W. Martin. That is so. 5365. And according to your own experience, and in 4 Mar. 1892. the mines with which you are at present connected, you do not think there is even that danger P-In some places where you have a very dry place, of course, it would aggravate an explosion. 5366. But you tell us that the dust in the mines with which you are most familiar is mixed with shale and stone dust ?-That is so. 5367. And is thus rendered innocuous ?-Yes, more or less. 5368. Under those circumstances do you consider it necessary to take any precautions against dust in such mines P-Yes. 5369. Why P-Because I would not trust dust at all under any conditions without damping it. 5370. Therefore, although in your experience you have no knowledge of any danger caused by coal dust, you think that there is a danger which ought to be provided against ?-I do. 5371. Now, will you tell the Commission what precautions you think ought to be taken ?-I think that the dust should, as far as possible, be removed from the main roads, and that damping should be carried on in addition. 5372. Where should the damping be carried on P-In the main roads. 5373. Only in the main roads P-Yes, I think the greatest danger is to be met with in the main roads from dust. 5374. Would you make any attempt to damp down at the face P-I do so in one instance, as shown on plan. I do not think it is absolutely necessary to extend it further. 5375. Would you explain to the Commission what your system is ?-I have some tables of hygrometric readings taken of our system of damping dust by compressed air and water, and also photographs of the spray. I am not a photographer, and I have brought the best I could. That is a photograph of the spray of compressed air and water (producing photograph). It shows how light it is, and that it is carried into all parts of the mine behind the timbers. That is another, and that is another (producingfurther photographs). It is so very light that it travels with the air current. 5376. (Lord Rayleigh.) Is the air used under high pressure in the hoses P-The compressed air is about 45 lbs. per square inch. 5377. (Chairman.) Now, is this spray created in different parts of the mine -Yes, it is created in different parts of the mine. I have a small plan of the mine (producig plan and explaining same). The air goes down this south pit, the down-cast, which is 334 yards deep, and it travels down the main drift. Thi is the line of faces. The air travels here, goes along to the face, up the working face, and back through the returns to the up-cast shaft. 5378. It follows in all respects the course of the ventilation P-That is so. In this case the pipes for carrying the compressed air were first laid for pumping at the bottom of the drift. We use the same pipes for pumping and for supplying the compressed air for the sprays. Then, we lay pipes from springs in the pits, and get whatever pressure of water is necessary, generally about 90 lbs. to the square inch, so that, if the air compressor stops for any reason, we are able to produce a fine spray with water alone under a pressure of 90 lbs., which is increased as the workings extend by the extra depth, the drift dipping about 3 inches to the yard. 5379. How do you get the pressure on the water P-The pressure on the water is got from the height of the spring in the pit. 5380. What is the position of the sprays in the course which you have just shown us on the plan P-I have had them numbered Nos. 1, 2, 3, and so on, right up to 23. No. 23 spray is absolutely in the colliers' face where they are working a long wall face. I should perhaps explain, too, that Nos. 27, 28, 29, and others, are in the main return, and damp the dust in the main return wherever we chose to take it. We take it into the return at every level, say every 300 yards, and so damp the dust in the intake and the returns. D2 28 Mr. ROYAL COMMISSION ON EXPLOSIONS 5381. What is the average distance between the difsprays P-Here is a table of hygrometrical readings that I have had taken. No. 1 spray is 161 yards from the pit, the next 264, 374, 560, and so onat varying distances. My evidence in this matter is borne out by Mr. Galloway, who has seen these sprays. He thinks that one in 200 yards would do all that, but I have them from 50 to 60, 70, and 80 yards right through. 5382. You think that one in 200 yards would sufficiently damp the dust P-Yes; but there is very little saving in reducing the distance, because if you have them in every 100 yards you need not work them together, you can work them alternately. The difference between the wet bulb and the dry bulb is about two degrees-54 and 52. Then at 60 yards beyond the spray you get perfect saturation, and another at 65 yards, and another at 44, always keeping the tempera. ture down and getting perfect saturation at those distances. It takes a very long time to get a large number of readings if you want to get the maximum distance. I have not taken the maximum distance here. It depends greatly, too, upon the velocity of the air in the mine, the distance which you can convey the moisture. In No. 2 Bedlinog Pit, a very deep pit, and which is more dry and dusty, except in places where we have water breaking down from a seam above, we have a very high velocity, and the greatest distance that we can get perfect saturation with water alone under pressure is something like 18 yards; that is with a velocity of air travelling at 1,000 feet per minute. Here we can get it 70 yards, and the velocity only from 250 to 300 or 400 feet. 5383. I understand then that in the deep pit in which the saturation is only carried 18 yards the difference is due to the fact that in that pit you have not got compressed air P-That is so. 5384. And that in order to carry the saturation a considerable distance it is desirable that the water, even although it is at high pressure itself, should be accompanied by compressed air at high pressure also ?-That is so. Only you do not require the water at the high pressure with compressed air, except that should the compressing engine fail you can produce a spray independent of the air compressor equal to what you can produce with ordinary sprays under water pressure alone. 5385. But the most efficient result is attained when you have the compressed air ?-Undoubtedly. That is the system that Mr. Atkinson, one of Her Majesty's inspectors of mines, wrote you upon, and of which he said, I think, that it is certain that under that system no explosion from dust could possibly occur. 4 W. Martin. ferent 4 Mar. 1892. 5386. Now what is the effect of this saturation upon the dust in the main roads P-It absolutely damps it. 5387. Is it damp to the bottom, because we have been told that in ordinary damping only the surface of the dust is damped, and that the water remains on the surface while underneath it is as dry as ever P-This damps it thoroughly. Of course if a mine is left to accumu- late so much dust that you cannot damp it, then the simplest method is to remove the dust. A river will not damp some places, if they allow the dust to accumulate. 5388. You do not think in any system it would be safe to dispense with the occasional removal of the dust P-Certainly not; the more they remove the dust the less water they will require for damping, and the healthier the mine and the safer in every respect. 5389. And by your system do you find that the dust which remains, which must always be a thin coating if you are constantly removing it, is saturated P--I do. The fine and dangerous dust that I think lurks in the sides and roof and behind the timbers-that very fine dust that the gentleman who made the experiments with dust endeavoured to obtain by fine brushes, is absolutely damped and rendered, I think, harmless. 5390. Have you any other plans to show us P--This (producing anotherplan) is a detailed plan and section showing how this spray is worked. The compressed air is taken in one pipe and water is taken in another. They are brought together, and there is a nozzle here through which the air goes; the water flows up the other and it simply forces fine spray, absolutely as fine as steam, and which you can see after the tables are read at the hygrometer travelling on the air. FROM COAL DUST IN 1MINES: 5391. (Sir Williacc Lewis.) In each case in the direction of the current P-Yes, that is so. 5392. (Lord Bayleigh.) Is this nozzle attached at the end ?P-Yes, that is attached at the end. 5393. We understand that these sprays are at work day and night ?-No, we work them whenever it is necessary, very often at night and not in the day. 5994. For a limited number of hours P-Yes. 5395. (Chairman.) I gather that by this scheme the spray permeates everywhere P-It does. 5396. And will go into corners, and on to the roof and the timbers, and every part of the mine is saturated ?-Yes, wherever the air travels. 5397. Does the system incidentally improve the ventilation and temperature of the mine P-It does. 5398. Now, in how many of your collieries is the system at work P-Three. 5399. And for how long has it been at work P-Since about 1886. 5400. (Sir William Lewis.) That was the first P-Yes. That was before we went in for it largely. The experiments started in 1886. 5401. (Chairman.) To what extent has this system been carried out in any particular mine P-At the South Tunnel pit it has been carried out very largely; the plan of which I have handed to your secretary. 5402. What is the total length to which the system is carried in that mine ?-I believe we have over 3,000 yards laid there now. 5403. And you consider that where this system is adopted, an explosion from coal dust would be impossible P-I do. 5404. Is that also the opinion of the mining inspectors who have seen it P-It is the opinion of Mr. Atkinson, taken from his letter to you, and it is the opinion of Mr. Galloway. 5405. Can you tell us whether this system has been adopted by any other mine owners P-Yes, it is adopted by the Plymouth Iron Company's collieries. 5406. Where are those collieries P-In the Merthyr Valley. It is also employed in part of the Powell Deeffryn Company's collieries in the Aberdare valleys. I have sent some sprays up to Lancashire to some of the mining inspectors. I think Mr. Makepeace had some to try. 5407. Is the process a patented one P-It is. 5408. Is it expensive to apply P-No; it is not a matter that I have pushed at all in any possible way, but it produces a spray certainly far superior to anything I have seen. 5409. Would the expense of applying this system to a mine be considerable P-Where they already have compressed air working, it would be simply the laying of the pipes. 5410. And compressed air is frequently used in the mines for the purpose of working the mines P-Very frequently. 5411. Now do you think that any additional precaution ought to be taken with regard to lights P-No, not with regard to lights. 5412. Is there no danger in your opinion in the employment of naked lights in these collieries in which fire-damp is known to exist ? -I think the danger from explosions, due to the using of naked lights in a colliery, such as we have at Dowlais, is not so great as the danger due to accidents from falls of roof. The danger to the workmen using a naked light from the risk of explosions of gas, is not so great as the risk of falls of roof due to the want of a better light. 5413. (Lord Rayleigh.) I understand you to mean by your last answer, that more would be lost than would be gained by the adoption of a safer light, which would entail a less degree of illuminosity P-That is so. 5414. As to the use of spray, can you say whether there is any serious objection to the use of sprayP-None whatever, I think. 5415. I think some witnesses have suggested to us that there would be difficulty from the breaking up of the floor in certain cases ?--'hat is where you overdamp the floor. If you make the floor thoroughly wet, which a large number of the water sprays only do, you may get an upheaval, and do get upheavals; wet floors, where you have a heavy squeeze, make the bottom rise. MINUTES 29 OF EVIDENCE. 5416. But you think all that is necessary to be done for the purpose of damping the dust can be carried out without entailing that risk P-That is so. 5417. (Mr. Bainbridge.) Which coal seams are you working in those mines P-We are working all the known steam coals in the Merthyr and Aberdare Valleys. 5418. And which do you consider the most dusty to a dangerous degree P-I think the most dusty is the nine feet. 5419. And which do you consider the most fiery ?There is not much to choose from. It much depends on the kind of roof you have, and the position of other seams above or below. 5420. What lights are you working with P-We are working a bonnetted Clanny in some collieries, and we are working with naked lights in other collieries. Out of the total quantity that we raised last year, we used safety lamps for about one-third of the quantity, and naked lights for two-thirds. 5421. Are you working naked lights anywhere where you are having these precautions against dust P-Yes. 5422. You are taking the precautions against dust, then, in some mines that you are working with naked lights ?-Yes. 5423. Are these precautions for sanitary reasons or for danger P-For danger. 5424. Then you are using naked lights now in mines where you consider dust is dangerous P-No, not where I consider dust is dangerous. 5425. Might be dangerous P-I perhaps go further than a great many people in damping. I think it is better for the colliers to work in; they are very pleased with it. The mine is far more pleasant to work in as well; and not only that, but I am doing it with a view of extending that system of damping throughout every colliery we have. 5426. But keeping to the mines that are worked with naked lights, I take it that those are the mines that are not free from gas ?--Yes, but we shoot there largely. 5427. But they are quite free from gas P-Oh, dear, no. 5428. They have gas in them P-Yes. 5429. Then they are worked by the long-wall system, IsupposeP-That is so. If you will pardon me explaining, we have a large number of collieries that have been working for many years, and have beenl worked from the crop down to a great depth without any break. These mines are absolutely more or less damp, and free from dust; but from the crop down they have all made more .or less gas, and during the many years that they have been worked we have had large numbers, speaking now from the old days, of small gas explosions-no serious ones. But in our wider and deeper collieries, the Bedlinog Colliery for instance, they are about 600 yards deep; they are divided 'by faults and pillars of coal, large pillars of coal, from the other collieries. In this colliery we have, within the last couple of years, had five very serious outbursts of gas. There we work entirely with safety lamps. 5430. (Sir Willian Lewis.) That is Bedlinog P-Yes. 5431. (Mr. Bainb?dge.) Coming back to the places where you are working with naked lights, I only want to understand whether you use the spray there for sanitary reasons or to provide against danger P-To provide against danger. 5432. As well ?P-Yes, as well as for sanitary purposes. 5433. Then you think, if you did not provide the damping arrangements, you would run the risk, as you are firing shots occasionally, of having an explosion of coal dust alone P--No, I do not think so, I do not think we would there. 5434. Why do you damp the dust, then ?-Simply because I believe that it is a thing that will have to be done everywhere. I think it is a proper thing to do, 5435. Because of the danger, do you mean F-I do not wait until we get serious danger. 5436. You said you were providing against danger; what was the danger that you were providing against 4 -- I think that there is always more or less danger underground. 5437. Then it would be the possible risk of an exMr. plosion which would be there if you did not damp the H. W. Martin. dust ?P-That may be so. Yes. 5438. In that particular case do you use explosives 4 Mar. 1892. on a large scale ?-A very large scale. 5439. What explosives do you use P-We have been using dynamite and powder chiefly. We are now using roburite as well; we use the three. 5440. Is there anything you would like to tell the Commission with regard to your experience in explosives P-I am sinking two very deep pits at Aberdare Junction at the present moment for the Dowlais Company, and lately I had a serious accident with the man who prepared the shots. He used to warm the water in a small kettle, which was kept for the purpose in the sinker's cabin, and poured the water into the bath, the ordinary dynamite pan. One day he did not go for fresh water, but he emptied the water from the inside of the bath into the tin kettle. He took that water and Dut it on to the fire, and be very soon had a very serious explosion, which killed him and burnt a boy very seriously. I think this was caused by the nitroglycerine exuding from the dynamite cartridges, and when he poured the water from the pan into the kettle probably a very little nitro-glycerine went in with it, which was quite sufficient to do the damage. I have abandoned the use of dynamite altogether, and I have taken to gelignite instead. 5441. That is for sinking shafts P?-Yes, and for blasting top underground. I have given up the use of dynamite altogether. 5442. In using gelignite, do you use it in conjunction with water or by itself P-By itself. 5443. Do you find it flameless P-No. I do not know that any of them are flameless. 5444. Do you find roburite flameless P-It shows less flame, I believe, than the others, but I very much doubt myself whether any of them are flameless. 5445. Would you regard it as a very serious thing to have explosives entirely done away with in your mines P -Most serious. 5446. And with that in view, you are aiming, I suppose, at trying to find an explosive that is less inflammable than gunpowder P-We endeavour to do all we possibly can to minimise danger from shot-firing. 5447. Do you think you have not succeeded in finding a flameless explosive yet P-I do not think so. 5448. With regard to watering, the Chairman asked you about the expense; can you give us an idea of what the cost would be in that case where you have 83,000 yards of pipes ?--I cannot give you the cost now. Of course it is simply a matter of so much per yard of piping and fittings; that is absolutely what it has cost us. 5449. Would it cost 1,0001. for a mine of that kind P -- No, nothing like it. 5450. I see you seem to have, at every point where you bring the air and the water together, two brass valves ?--That is really a very small item. As I have said before, I have not pushed this matter, and I can hardly tell you the cost of these little things, but it is a very small item in the management of a colliery. 5451. I was not referring so much to your particular process as to watering generally, where watering is done thoroughly, whether the first cost becomes an important item ?P-Yes, undoubtedly; everything in these days adds to the cost. 5452. Can you tell us in the case where you have the water taken down at a pressure of 90 lbs. due to the head of water, what is the pressure of air you have ?45 lbs.; that is the pressure of air that we used for working or hauling engines and pumps. 5453. Then, in mixing together the air and the water at relative pressures of 45 lbs. and 90, I suppose the mixture is entirely regulated by the position of the nozzles ?-Yes, and there is a tap to each pipe, one regulating the water and the other regulating the compressed air. 5454. And your men, by degrees, get accustomed to the exact position of these nozzles, so as to give the right degree of saturation ?-Yes, quite so. 5455. Are your mines at all subject to upheaval of the roads P-Yes. D3 30 ROYAL COMMISSION ON EXPLOSIONS FROM 5 156. Then do you not rua some risk in a large mine Mr. H, W. Martin. of having the pipes broken by upheaval with a high pressure of water; in case of their being broken, would 4 Mar. 1892. not the water flood the mine P-Oh, dear no, the amount of water would not affect it in that way. 5457. What size of water pipe do you use P-Beginning, say, at 2 inches; of course, the size of the water pipes and the quantity of water that you would use depend upon the extent of the mine, the number of the sprays, and the quantity of the dust. 5458. Your experience is that there is no difficulty, as a rule, with regard to accidents to the pipes themselves P-No, none whatever. That is a very small matter, a less matter than if you are pumping at a dip, and the pipe broke for a few moments. 5459. Lord Rayleigh asked you with regard to the time those sprays were at work; can you tell us what proportion of the total working hours, or the total 24 hours, your sprays are working, roughly speaking PI think if you work these sprays for an hour of an evening, it would be ample, and work them alternately, so -that you would not make it a burden upon the compressor. 5460. Each spray working about an hour per tlay ?Yes; and of course that again depends upon the state of your mine. I could not answer for what it would require for a mine like some of them in the north, where it is said they are so very thick with dust. 5461. Are your mines worked by fan or by furnace ? -We have some by furnace, some by fan. .462. Do you find that the cooling of the return air current by this process at all checks the ventilation PWhat it does is this: when you have 14 sprays running at the same time, I find, taking the water gauge at the separation doors at the bottom of the pit, that it increases the water gauge about one-tenth. 5463. Then you get the ventilation somewhat impeded P-You benefit it by cooling and by damping, but you add to the water gauge due to the velocity of the air. 5464. Do you find no change in the volume of air POf course the volume of air would change in proportion to what the water gauge shows. 5465. Have you ever measured to see P-It would be very light. It is too small a matter, I think, to affect us at all. 5466. The volume of water perhaps you cannot tell us, can you P-We use about from three to four gallons per hour per spray. 5467. On the average P-On the average we make the spray so fine that if you pass your hand close to the spray it simply just wets it. 5468. You mentioned that you had recourse to the removal of the dust as well as damping P-Certainly. 5469. If you damp it as well as your process does what dust is there left to remove P-You will get it into mud if you extended it sufficiently far. 5470. I mean dry dust, what dry dust have you got to remove in your mine P-None, where you absolutely damp. But I have not even extended it throughout the whole mine. I am extending these sprays in the main ways chiefly with a view that if an explosion occurred my main ways would be saved, and we would be able to give relief and succour to those perhaps who were left in the faces of the mine. 5471. With regard to safety lamps, have you succeeded in finding any lamp which gives you such an improved light as to reduce the accidents that you refer to by falls of roofs P-I have tried electric lights; I havetried that lamp that gives the best light. 5472. The long heavy lamp P-Yes. 5473. (Sir William Lewis.) At all events a recent lamp P-It is a new lamp. 5474. With a compound name P-Yes. 5475. It is a very heavy lamp, and it gets hot P-It does get hot, but I think a great deal of that is due to the wannt of care in starting to use it. 5476. (Mr. Bainbridge.) Are you yourself a believer in the idea that an explosion can take place from coal dust alone, without fire-dampP--No, I do not think that coal dust alone without fire-damp will initiate an explosion. COAL DUST IN MINES: 5477. (Sir William Lewis.) Do you find any difficulty in your district in getting the workmen to make the examination which they are entitled to make under the 39th General Rule of the Mines Inspection Act ?Whenever they like to go they go, but our colliers are satisfied not to go. There is more difficulty in getting them to give up the time than anything else. 5478. You can only speak as to experience at your own collieries P-That is all. 5479. You referred to experiments made at Dowlais by Mr. Galloway, in answering a question from the Chairman, those experiments were tamping with coal dust P?-That was so, and with the dust placed upon shelves and fanned up in a box. 5480. Were they not for the purpose of ascertaining whether there was a flame with blown-out shots P-That was so. 5481. Will you tell us what was the result of the experiments of Mr. Galloway and yourself; I know you took a very prominent part in them ?-They ignited dust. 5482. That is the flame from a blown-out shot ignited dust ?-Yes. 5483. Have you ever had a similar experience underground where a blown-out shot has ignited the dust PNever. 5484. You do not know of any such thing within your experience P-No, never. 5485. Do you think it is possible for a blown-out shot to inflame the dust in a confined space underground PWithout gas P 5486. Yes P-No. 5487. Not to inflame it P-No. If you have a blownout shot of powder, so long as the sparks from the powder are travelling with great force through fine dust they may inflame it, but simply close to the sparks of powder. 5488. Do you, or do you not, think it is possible that a blown-out shot may create an explosion without gas PCertainly not, that is under the conditions that we see the dust in a mine. 5489. Assuming, if you like, that the manager neglects to remove the dust in the neighbourhood of a place where a shot is going to be fired and that that shot is unfortunately a blown-out shot, can you believe that that shot may create an explosion although there is no gas there P-I do not think it would, but I would prohibit firing two shots in the same place at the same time. 5490. For what reason?P-For the reason that you may have two blown-out shots; one will raise the dust and the other may fire the gas; then under the con. ditions under which I read, gas has been fired by Mr. Hall in his pit. 5491. Assume there is no gas there P-I am still assuming that; I do not believe that it would occur, but you would get so near the actual experiment carried out by Mr. Hall, that to avoid this probable danger I would prohibit the firing of more than one shot underground at the same place and at the same time. 5492. But you have heard of accidents where it has been suggested that one blown-out shot raised the dust and the shot immediately following it created an explosiot, or what you would perhaps describe as an inflammation P-I have heard so. 5493. And your object in preventing two shots being fired almost simultaneously would be to prevent the risk of such an inflammation P-That is so. 5494. But you do not think that could possibly create an explosion P-No, I do not think so. 5495. Now with respect to the provisions of the Mines Act for clearing dust and examining the place before shots are fired; have you anything to suggest to the Commission as to any improvements that your experience would recommend in that direction P-No. I think that it is absolutely necessary that dry dust should not be allowed to accumulate, and that in all cases the main roads should be watered, damped, to what extent I would hardly say, but to a large extent. 5496. Then you said that you had recently adopted gelignite P-Yes. 5497. Have you had any complaints from the workmen as to the fumes after putting off shots with MINUTES IN EVIIENCE. gelignite P-None so far. It is only recently that I have adopted gelignite. 5498. Have you tried it in enclosed spaces such as narrow headings P-In a few. 5499. Have the men complained or not P-Not yet. I may tell you that it is only recently that we have begun to use roburite. 5500. Have you followed closely the results of the experiments both in Wales and in Chesterfield, as well as in the north, with respect to obtaining explosions from coal dust P-I have. I have read several accounts of the inquiries. 5501. And with your knowledge and experience you have come to the conclusion that it is impossible to initiate an explosion with coal dust alone ?-With coal dust under the ordinary conditions of working a mine. 5502. Would you consider that there would be any advantage in further experiments in the same direction on a larger scale P-For myself, I am perfectly satisfied without any further experiments. I believe there are some people who would still desire further proof. 5503. You have little doubt yourself ?-I have no doubt whatever. 5504. And there is no need of any farther erperiments so far as you are concerned P-Not a bit. 5505. (Mr. Fenwick.) Do you carry your practice of damping to the working face ?-We have, in this instance of the one pit that I have given you the plan of. 5506. Only in this one instance P-Only in this one instance. 5507. Generally, you confine the damping to the main roads ?-Yes, and the most dusty parts of the main roads. 5508. Do you suggest that the damping process should be carried into every division of the main roads P -I do, that is where it is dry and dusty. 5509. What course do you adopt in removing the dust; do you brush it P-No, we fill it into trams, into tubs. 5510. In that case will not you only get the heaviest particles of the dust P-But our mines are really not dry and dusty in the sense that you have had some evidence from the collieries in the north, and from some of the collieries in South Wales too. 5511. Then you do not think that it is necessary to adopt the system of brushing, do you, to remove the dust P-Not if you damp. 5512. Has your experience in South Wales been confined to mines principally in the steam coal district ? -Steam coal and bituminous coal. 5513. I think you said that in the steam collieries you had had experience of explosions, but they were very slight P-That is so. 5514. At what collieries were they P--At all our collieries; we have some 10 or 12, and we have had explosions in all. 5515. Were there any lives lost P-Sometimes a few ; one, two, three. 5516. Not more than that P-No, I do not remember any more. 31 5517. Principally, I think you said that you work Mr. your low seams on the principle of the long wall P-We II. W. Martin. work all long wall, nothing else, excepting in the bituminous coal. 4 Mar. 1892. 5518. On a square face or otherwise P-Sometimes one way and sometimes another, but as a rule we keep all our faces square, without cuts. do . 5519. And you do not damp in those places P-No. 5520. Do you fire shots P-Where we fire shots we damp. 5521. Have you any gas in those places P--Yes. Are you speaking of naked light collieries, or of safety lamp collieries at the present moment ? 5522. My question would apply to both cases f-Where we fire shots out of the reach of the watering by piping, then we water by casks; take casks of water and sprinkle it about the ground. 5523. Where you have the presence of fire-damp, do you think that it is safe to fire shots under any conditions P-Yes. 5524. Have you ever had explosions even with damping, where you had the presence of fire-damp PI do not know of one explosion we have had by firing shots into gas. 5525. Is the practice of damping, as provided by the Mines Act of 1887, pretty generally observed in South Wales, in your opinion P-Yes, I think it is. 5526. (Mr. Bainbridge.) I suppose you have read the accounts of most of the explosions which by some people are attributable to coal dust P--Yes. 5527. Have you in your mind such explosions as Seaham and Altofts ?-Yes, I know Altofts. 5528. And Elemore ?--.Altofts more particularly. 5529. Altofts being a place where an explosion took place when a shot was fired, and where, as far as could possibly be judged, there was no gas anywhere near the place, can you give us your own idea how that explosion could have taken place ?-Not if there was no gas. If I remember aright, they fired three shots; two together, and then one afterwards. 5530. And there was a very violent explosion indeed P -Yes. 5531. Extending for more than a mile P-Yes, I have seen the plan and I have read the evidence given before you. 5532. I mean with the view you hold as to coal dust not being able by itself to cause a big explosion, do you assume that there must be some mistake there with regard to the statement that there was no fire-damp in the pits P-Yes, it is evidently a mine that makes a lot of gas, that was shown by the fires afterwards. 5533. Yes, at the face, but this was a long way from the face P-The fact that they had an explosion which they attribute to shots fired into dust alone is my chief reason for suggesting to you, gentlemen, that I would add to the general rule a clause prohibiting the firing of more than one shot at a time in the same place. 5534. But from your own point of view you do not think that explosion could have taken place in coal dust alone, is that so P-I think it could not. The witness withdrew. - Mr. GEORGE WILLIAM WILKINSON called 5535. (Chairman.) You are, I think, general manager of the Risca Colliery and the Abercarn Colliery in Monmouthshire, and the National Colliery and North Dunraven Colliery in the Rhondda Valley, Glamorgan.. shire P-Yes. 5536. What is the character of these mines P-They are very dry and dusty and gaseous. 5537. Have you had any experience of an explosion at any of them P--I have at Risca. 5538. When did it take place ?-In 1882, on the 15th of January. 5539. What was the cause of it P--In my mind undoubtedly a blown-out shot in the main intake. 5540. Did coal dust play any part in that explosion P -It did. 5541. Will you give the Commission the details of it P-I think I could more easily explain it to you if you and examined. had this plan in front of you (producing and explaining plan). This represents the downcast, this the upcast, and the main intake is here. There were four shots fired and a fifth which had not been fired. I may mention generally that it was under exceptional circumstances; all the men were removed, and there was no one in the colliery except the officials and one man who had drilled the holes. The shots were here in a current of air of about 60,000 cubic feet. The first shot was fired at this point, and it had evidently done its work; then they fired a shot here (represented by a section in the top), and then the men retired and fired two of these holes and it got to this point, when evidently a very violent explosion occurred. My opinion is that this was caused by the second shot, which had hung fire, firing right across the road, as it were, or rather in this direction. The concussion from the third and fourth shots had evidently started the dust, and as the dust passing from these shots had come opposite this D4 Mr. G. W. Wilkinson. ROYAL COMMISSION Mr. G. W. Wilkinson. 4 Mar. 1892. ON EXPLOSIONS FROM COAL DUST place, the second shot fired into it and caused a most violent explosion. Everything points to that. 5542. Was there any presence of gas P-None whatever. These are solid pillars of coal in every direction. It is a very hard rock roof, and the holes are in existence to this day after a lapse of 10 years. The explosion went to bank, blew the top of the fan off, tore the iron trams in this direction like shreds of paper, killed 60 horses here, and the four men, three officials and the shot-firer. There were few or no marks of burning upon any one of them. 5543. The mine is, however, a fiery mine P-It is a very fiery mine, but this was in the main intake within 200 or 300 yards of the bottopn of the pit. 5544. And your reason for supposing that there was no gas there at the time was the extent of the ventilation ?P-The extent of the ventilation, and the fact of this roadway practically being a stone drift. The coal was some 3 or 4 feet below the roadway, the top had been constantly ripped, and it was solid rock on either side. 5545. If your theory is correct, the third and fourth shots raised a cloud of dust which was carried to where the second shot was hanging fire, then the second shot gave out P-That is so. 5546. And then the explosion took place ?-Yes. Everything goes to confirm that. 5547. What was the result of the inquiry which was held into the explosion P-Accidental death, but I think there was no reason given except " from shotfiring." 5548. No allusion was made in the verdict to the presence of dust -- No, there was no allusion to that. 5549. Then from your experience, and especially from your knowledge of what took place in this explosion, you think that the presence of coal dust is a serious danger P-A very serious danger. 5550. And that it may even be the cause of an explosion without fire-damp P-Undoubtedly, in my mind. 5551. What precautions do you think it necessary to take against this danger P-To thoroughly water the ways; in fact, to saturate the atmosphere. 5552. Are you acquainted with the process which has been described to us by Mr. Martin P-I am. 5553. Do you approve of that P-I do where it is practicable. The spray system that we use is merely the pressure of water without any air. 5554. You do not use compressed air in your collieries ? -I have not hitherto. At several of our collieries we have no compressed air. I think that this is such an important point, and that the saturation is so absolutely necessary to the safety of the mine, that it might and could be automatically maintained. This is a theory that has merely presented itself to me, but I think it is worth consideration that a thermometer could be so constructed that when the air becomes saturated to the dew point, the taps could be regulated by meaps of some electrical arrangement which could be worked by the wet and dry bulb thermometer. 5555. So that the saturating spray you mean would be turned on if the thermometer showed that the air was not sufficiently damp P-That is so. 5556. But is there any objection to the spray being always on P-No, except that there may be a time when there would be no spray on. It could be so arranged that there could be a tell-tale, and communications could be made to the cabin or even to the offices on the surface. 5557. Now, do you consider that with compressed air spray can be more conveniently arranged than without it P-I think so. 5558. You would prefer to use compressed air if the other circumstances allowed you to employ it P-I should prefer to use compressed air. 5559. Then besides the saturation of the atmosphere of the mine, are there any other precautions that you would take P-In shot-firing particularly P 5560. Yes, in reference to shot-firing P-To use an explosive that was flameless, or as nearly so as possible. 5561. What explosive do you consider is flameless PI am using now absolutely ammonite at all our collieries, and I have been for the last two or three years, with very gratifying results, never having had any IN MINES: complaints from any of the shot-firers of their having seen any sparks or flame. 5562. Is there any complaint of bad gases given out by the explosive ?-No, none whatever; it is spoken most highly of. 5563. You do not think that the use of powder is a necessity in any mine ?-Not at all. This explosive is as strong as any of the high explosives, either gelignite or dynamite or any of them. 5564. In your experience you prefer it to all the others P-I do, from experience. 5565. Have you used any special apparatus in blasting P-I think I have tried them all. The first I believe that I remember was the Grafton Jones hydraulic wedge, which we tried in South Wales at the Powell Duffryn Collieries. I also tried Chubb's wedging machine (a series of cylinders), and Bidder's wedge (a hydraulic wedge). I have also used the compressed cartridge used in Staffordshire. That is a castiron cylinder compressed with air up to 15,000 or 20,000 cubic feet of pressure per square inch until really it burst. I had very gratifying results from it, but it was very expensive like the other process. I have also tried the lime cartridge in South Wales. Where I found that the coal was friable it practically spent itself in the slips or in the crevice in the roof and did really more harm than good, but where the coal happened to be very hard it worked remarkably well. I have also tried, of course, Sir Frederick Abel's water cartridge, but that is merely an envelope to envelop any of the ordinary explosives. 5566. With regard to these wedges, is it your opinion generally that they are not applicable P-They are not, they are very cumblersome to get from place to place, they are expensive and liable to get out of order, and they require a very large hole to be drilled. That must, in the majority of instances, be done by manual labour, and if a stone or a piece of brass or anything like that is met with in the hole, the hole has to be abandoned and a fresh one is started. 5567. And you think that if the precautions you suggest were taken, that is to say, if a flameless explosive like ammonite were used in shot-firing, and the air of the mine kept saturated, there would be practically no danger from coal dust P-Practically no danger. I should like to see the dust first removed, or some months to elapse beforte shot-firing was allowed in a dry and dusty colliery, so that the dust would become also thoroughly saturated or permeated with the water, not to have merely a scale on the surface. 5568. Have you had any gas explosions at your collieries P-Yes, we had one at the National. 5569. Did coal dust play any part in that P-Undoubtedly ; but it was from a shot, and there may have been gas; we had no evidence to prove that there was no gas. We were then using, or supposed to be using, " Abel's envelope," but we discovered that they had been neglected to be filled with water, and the consequence was a most disastrous explosion. 5570. Is there anything else that you wish to say P-I do not know that there is anything that presents itself at present. We have had several very heavy outbursts of gas, of course, as we have in South Wales, which may account for many of these accidents, but I do not know that that would at all bear upon the question of dust explosions. 5571. (Mr. Fenwick.) With reference to the explosion to which you referred, and which occurred at Risca, was that the explosion in January 1882 P-Yes, on the 15th of that month. 5572. I think you said that there was no evidence to showi that it was a dust explosion, did you not P-I do not know that I said that. It was a dust explosion undoubtedly. 5573. Had there been found any gas there for some time previous ?--No; none whatever. 5574. What distance was it from the shaft ?-230 yards, I think. 5575. Do you remember the volume of air that was passing at the time P--I think it was about 60,000 cubic feet, between 55,000 and 60,000. 5576. I observe in the report which is given of that explosion that it is stated by the inspector, Mr. Cadman, that the gas was supposed to have come from some old workings; were there any old workings near to where the shot was fired P-None whatever. None MINUTES OF EVIDENCF. near, as you can see by the plan, and as can be seen to thi- (lay, there are no old workings near it, '5577. (Sir William,Lewis.) Have you always been of the opinion that the explosion was due to coal dust PIt was my conclusion then, as it is now, that it was due to coal dust. 5578. You held that opinion then P--Certainly ; and I gave evidence to that effect before the coroner. 5579. Then with reference to the National explosion; in examining the effect of the explosion throughout the workings, did you observe whether it was intermittent; that there were traces of dust t6 he found, and then that they ceased for a time, where there was water or any dampness P--That was so. 5580. That was the result of your investigation at the National P-That was the result of our investigation. 5581. Were there any similar indications in Risca, when you examined that after the explosion P-Yes, there were; but they ceased going in one direction, I may say, at a water parting which we had, not very far from the seat of the explosion. 5582. Do you happen to remember noticing the extent that it may have leaped over a damp place P-No; it ended at these damp places. There was a length of' dampness, in fact the timber alnd everything was thoroughly saturated, and it ended,there. 5583. Do you use water cartridges at present P--No, I use ammonite pure and simp'e. This is one of the cartridges (producing cartridge). Of course it is not filled with the explosive, it is filled with plaster of Paris. That is the description of cartridge we use. 4584. After the explosion which you .-bad at the National, and which you said was due to the neglect of the men in not filling the cartridges with water, you have ceased using them P--Yes, we have ceased using 5598. Were the roads in the immediate neighbourhood of these shots watered P-I may say that the roads were perfectly damp, as hard almost as this table, it was on the sides and the roof where there was probably a quarter of an inch of dust, impalpable dust, adhering. 5599. No provision was then made in regard to the dust which adheres to the roof P-None then. 5600. Would you say that Mr. Cadman had no reason for stating what Mr. Fenwick mentioned just now as to the firing of shots causing gas to be drawn out of the old workings P-None whatever upon the face of it. 5601. You refuted that at the time yourself?PCertainly. 5602. What was the result of the Risca explosion with regard to your own watering arrangements P Did you, then, from that time carry out some plan for watering the dust above as well P-Yes, and we ceased shotfiring. We have never fired a shot in that seam since. 5603. Not of any kind P--Not of any kind. 5604 But now that you have your new experience with ammonite, would you think there was any danger in firing shots P-No, not a bit; we are using'it in the seam below, in the lower black vein, not in the black vein proper. We do not require it there, it is a thick seam about 9 feet, and we do not require it. 5605. You have got, in the habit of not using shots there, and you have not used them P-No, we have not required them; if we did require them they would be required in this, place where the shot was fired before. That would be the only place where we would require a shot. 5606. In your judgment, as to what coal dust would do and not do, I note that you differ from Mr. Martin ? -.-Yes. 5607. In spite of ti at yon both adopt the sname precautions P-I adopt precautions in watering the mine. 5608. And so does he, but you think that coal dust is much more dangerous than he does ?- There Perfectly flameless according to all the experience aind is not a doubt in my mind. Even last week I made according to the experiments with it which I have beei experimhents in a tube, and fired coal dust alone remaking within the last few days. peatedly with dynamite. 5586. Have you had any blown-out shots P-Lately P 5609. With regard to the proposal that you made as 5587. With ammonite P-Several. to an automatic record of the condition of the mine, is it 5588. Have you had blown-out shots in the neigh- not your experience of automatic matters in coal mining bourhood of dust P--No; we thoroughly water the that they are not very reliable P-If they are properly neighbourhood of wherever any shots are to be fired, taken care of they are reliable, and I have heard several and really where we are firing shots it is in a wet seam, instances of this working most satisfactorily. thenim. 5585. And so far as ycu have 'had experience of ammonite you consider it is perfectly flamelessP-- and we are not shooting in the very gaseous places. 5589. Do you use ammonite in the face in coal getting, or simply for taking down the roof?- For taking down the roof only, not in the coal. 5590. You use no explosives inthe actual coal getting. do you P--None. 5591. Wold yon consider it possible to carry on the collieries of South Wales without the use of any explosives P-Impossible at a profit. 5592. It has been suggested to the Commission by a witness that it would be very desirable that fireme should report the existence of dust as well as the existence of gas (if either gas or dust did exist) in their inspections in the morning; do you think that would be any advantage P-Yes, it would; but then it would be a question as to the extent of the dust, and as to their private opinion; in one man's opinion it may be very 5610. Would you not feel more inclined to rely upon a well arranged discipline of the mine. making sure dusty and dangerous; and in another's it may not. tamped. a flame. 5593. Would it not be very difficult to define P-Very, indeed. 5594. Would it not be better to rely upon the present provisions, that the dust must be removed and attended to before any shots are fired P-I think so. On second thoughts, I do not see really that it could be put into the hands of a fireman, in fact of any individual. I think that all the 'precautions of the Act should be carried out in their entirety. 5595. (Mr. Bainbridge.) With reference to this Risca explosion I should like to have a little further explanation; you were the manager at the time, were you not P -I was. 5596. It was a,dusty mine P-Yes.. 5597. T see that Mr. Cadman, the inspector, remarks, " I should here remark that the main roads are regularly watered," was that so P-They were watered by watering cans or water tanks, and the atmosphere was not saturated as it is at present. E 82480. that your manager, and for a certain number of hours of the day your under manager, had to look after these sprays P-I would have both. 5611. One would check the other P-Yes. This is a matter which occurred to me yesterday, and I have not had an opportunity of thinking it out, but I thought such a thing would be possible. 5612. With regard to the use of ammonite, as we have not heard very much of that befoire on this Commission, perhaps you can tell us a little more about it'. Is anybody else using it beside yourselfP-Several places in the north of England and in Staffordshire, and a numpber of places in South Wales. 5613. And you have never found a flame at all with it P-I have never seen a flame, and I bave seen hundreds of shots, that is, not when it is properly If you fire it without tamping it you may get I tried it in the experiments Iwas speaking of last week and then could not get a flame. 5614. Without tamping you do P-Without tamping you do. I' fire it with a fulminate of mercury cap. 561. Thieat applies to all the so-called flameless explosives' P-Certainly. 5616. Then with regard to its economy, is there much difference between the cost of working with that and the cost of working with powder P-No. 5617. What does it cost P-About is. a pound. 5618. And you use about one half of that compared to what you would use of powder P-Much less. 5619. And you use a much smaller hole P-Yes. I have produced a sample of the explosive. 5620. Does that represent the size of the hole P--.In some instances; we have had very much smaller ones, even as small as the capsule at the top of that explosive I have produced. E M1r. G. I4. Wilkinson. 4 Mar. 1892. 34 M1r. G. W. Wilkinson. 4 Mar. 1892. ROYAL COMMISSION ON EXPLOSIONS 5621. In the cases where you have adopted ammonite, have you gone so far as to countermand the use of powder altogether P-Certainly. 5622. You have excluded gunpowder YP- We have excluded every other explosive than ammonite. 5623. With regard to the question of explosives generally in South Wales, do you go so far as one witness we have had, as to say that in your district the exclusion of explosives would increase the cost of working in most mines by 6d. a ton P-In some instances much more. 5624. More than that P-Very much more; in the mines I am connected with it would be very much more; is. would be nearer the mark, if not more than that. 5625. Then if you came to the conclusion that you had in ammonite, or any other explosive, an absolutely flameless explosive, would you think it necessary on the ground of safety to continue your precautions with regard to coal dust P-Certainly. 5626. Why P-I should certainly do so. 5627. Would you do so as a matter of additional safety P-Yes. 5628. As well as for sanitary reasons P-As well as for sanitary purposes. 5629. Now, with regard to the wedges, you seem to have tried them nearly all P-I think I have. 5630. There is one wedge you may not have tried, and that is the long feather wedge in which the manual labour is considerable P-Yes, I have, I am using it just now. 5631. How do you find it answerP--Very well indeed. 5632. In spite of the hard work it entails P-Yes. 5633. How long does it take to break the coal down ? -I have not used it in coal directly, our coal is a friable coal. 5634. You do not shoot in the coal P-We do not. 5635. Then the explosive or wedge is required entirely for the stone P--Yes. 5636. You are not shooting in the coal ?-There is no necessity. 5637. How long does it take to break the stone down ?-That varies according to circumstances, and depends entirely upon the nature of the roof. In an ordinary shale roof a very few minutes are sufficient ; if it is very hard it may take two hours, and then you would only get a capful. 5638. You would regard the wedge as much safer than the most flameless explosive P-I would. 5639. Why is it not more largely used P-On account of the expense and the slowness of the process. 5640. The expense, of course, is much less per day, but much more in the first cost; an ordinary feather wedge does not cost very much in wear and tear, does it P--No, very little. 5641. It is the first cost of the wedge P-Yes, but that is not very considerable. 5642. Do the employers find the wedge or the men ?P -The employers find the wedge in the instances in which I have used it. 5643. And you find the wedge answer pretty well PI find it answer very well indeed. 5644, (Lord Rayleigh.) Do you think any further experiments are required to elucidate the behaviour of coal dust ?P-Certainly; there cannot be too many, I FROM COAL DUST IN 3MINES: think. There is not a great unumber of' people who really believe in it now. 5645. Are these people capable of being converted by any experiments ?-Really I do not know. Some of them are very hard to make believe. 5646. Have you any particular experiments in your mind as desirable P-Yes, I think that they should be conducted upon the lines laid down by Mr. Galloway. I think they are very desirable. 5647. What are the particular issues ? - Merely having a. long gallery, a level heading on the surface. 5648. On what scale do you think it would be necessary P-Upon the same scale as we have them underground. 5649. Are you of opinion that experiments upon a smaller scale would not serve the purpose?-They are sufficient to c,nvince me and to convince all those who are under me. I had some experiments even last week. But some people are rather sceptical. My experiments were in a boiler merely, about 12 or 14 feet long, trunk-headed ends and filled with the proper proportion of explosive mixture of coal dust and gas, and the different explosives fired into it with tamping, and without tainping, an1d with very little tamping; and almost all the explosives we tried, with the exception of ammonite, caused an explosion-in fact, all those which really had solid bodies in their component parts, but all those that resolved themselves naturally into gases there was practically no danger from. 56-50. Then the experiments you have in view relate rather to the comparison of the different explosives among themselves? - Those that I have been conducting were simply to show, for my own guidance, the result of using these explosives in gaseous mixtures. 5651. Do you think that further experiments are necessary in order to settle the question as t, whether an explosion could be propagated over long distances by dust only P--It is such a very difficult matter to get a chamber long enough. 5652. What sort of length do you think would be necessary P-You would practically require a gallery ; a chamber of 200 or 300 yards long would hardly meet the case. 5653. And of what diameter ?-Say 8 feet by 7, the width of an ordinary heading. 5654. Do you think that experiments upon a smaller scale than that would hardly meet the case P-They would hardly convince people. I think the smaller experiments point to the conclusion that coal dust is explosive. I do not see that there is any necessity to carry them to a much larger extent; except to convince those who are sceptical, there would be no great end to be gained by it. The fact has been established beyond a doubt in my mind. 5655. In your own mind the experiments still most required relate rather to the comparison of different kinds of explosives ?-I think so. 5656. (SirWilliam Lewis.) Following up what Lord Rayleigh has been asking you about as to the advantage of further experiments, do you think there would be an advantage in convincing the workmen as to the danger of coal dust P-I think it would be of advantage. 5657. Do you think they would be convinced except the experiment were upon some such scale as a colliery P -I think the majority of them would be convinced if a large chamber was constructed to the extent that I am speaking of, and to the extent suggested by Mr. Galloway. It would be practically impossible, I think, to carry them out underground, as you are aware. The witness withdrew. Mr. R. Bedlington. Mr. RICHARD BEDLINGTON called and examined. 5658. (Chairman.) You have been engaged for a long time in the management of collieries, I believe P-I have, for 50 years. 5659. In what district P-For a great number of years in Monmouthshire and then in Glamorganshire. 5660. I believe you have been president of the South Wales Institute of Engineers P-Yes. 5661. I suppose you are acquainted with many collieries in different parts of England P-I. am. 5662. You are also consulting engineer to a number of collieries ?P-I am consulting engineer at collieries producing about a million tons a year. 5663. Now, with regard to the explosions in Wales, what has been your experience as to the cause P-I have in many cases examined into the question after an explosion, examined the workings and everything to try to arrive at a conclusion as to the causes, and in what part of the workings the explosion took place. In other cases I have carefully read the evidence. My MTNTTTES OF EVIDENCE. experience over all that period which I have named is :that I do not know of a single colliery explosion that Was not caused by gas. 5664. That is to say, the explosion was initiated by gas P-Yes. 5665. Do you consider that dust has played any part in the extension of the explosion P-Yes; I consider according to the quantity of gas there will be an amount of flame, and that that licks up, to use that term, the dust in the immediate vicinity and cokes it. According to the quantity of gas the flame will go a certain dis-. tance, but I think the scorching at great distances is caused by the heated air and by the coked dust. The force is very great where much gas is ignited; I have felt it in a less degree in the workings myself, and I say the force is very great by which the he(ated air is passed through the workings and the coked dust, and that scorches men, horses, and timber. 5666. Do you think that the ignition of the coked dust in itself produces an explosion P--No, I do not. In all my examinations of these cases I have had no reason myself to arrive at that conclusion. I believe it aggravates an explosion of gas. 5667. Does it carry it further than it would otherwise go P-I think not so much in flame as in coked dust, which, of course, scorches. I have laid my hands upon men, horses, and so on, and I have found that they are often covered with the coked dust. When the coked dust is in a heated state like that it would no doubt more or less scorch. 5668. You do not think it adds to the explosion ?No, I think not; 'not in a large degree. 5669. In the coking of this dust would not gas be disengaged P-In a small degree. I haveiseen the gas exploding underground and felt the effects of it. It seemed to me tobe a mass of flame. As I say, it does ignite the dust; but Ip do not think it adds materially to the mass of flame caused by the gas explosion. I have suffered, and I am one of the persons who have seen gas really exploding. 5670. In a mineP-Yes. 5671. On what occasion was thatP--One was, I should think, nearly 40 years ago. There was a certain amount of gas which was not known of; the man advanced into it, and I happened to be about a chain from him. I did not know whether the place was right or not, but I happened to be measuring the stall and I saw the mass pof flame in the stall. I threw myself on my face and it passed over me. Then there was the vacuum caused by the first explosion, the air rushed back, and then came back over a second time. The last time I suffered from the effects of gas I was by myself and was surrounded by flame. I was very badly burned on that occasion. So I more or less have seen what would be the effect, though, of course, it would be in the great explosions so much more, according to the quantity of gas there. 5672. Do you think it necessary to take any precautions against dust in the way of damping the mines P -1 think the Miniug Act provides, where a mine is dry and dusty arnd at all likely to contain gas, for the damping of the dust at that point and in the immediate vicinity. 5673. Do you approve of that precaution P-Well, it ,is a precaution, but I do not know, according to my long experience, that there has been any case brought home in which even a blown-out shot has caused an explosion. There are so many thousands, and tens of thousands, and hundreds of thousands, of shots put off without any ill effect that you cannot provide for a remote contingency. It is just possible, it may be, but stili it is not what we would call a practical danger. 5674. Then if you had to deSide you would not even take the precautions which are now ordered by the Mines Act P-I would not think it necessary, bit I: would say as it is a precaution one cannot be too careful in regard to these matters; still I would not think it really necessary, because from a long experience I have not seen any ill effects from it. 5675. Do you think it necessary to clear the dust away P--I think it is desirable as a matter of nuisance, of annoyance on the roads. 5676. But not necessary to prevent danger to life PNot to prevent danger. I do not think it is any danger to life; but still, of course, you do not want to be irhaling dust if you can help it. Mr. R. 5677. I think we may take it for granted that you do Bedlington. not think it necessary to take any special precautions with regard to explosives either P-In what way ? 4 Mar. 1892. 4 ,Mar. 1892. 5678. To use flameless explosives in place of powder ? -Yes; the careful handling of it. 5679. Do you consider it necessary in blasting and shot-firing to use some of these flameless explosives PIt would be desirable. If there is any doubt upon the question at all, and it can be obviated by the use of safer explosives, all the better. 5680. Only I understand you to say that you do not think there is any danger P-Not from dust exploding, that is what I mean. 5681. Therefore so far as dust is concerned you would not think it necessary to alter the character of the explosive P-Not on account of the danger from dust explosions; but, of course, if you have a flame where there is any gas, then I believe that precaution is necessary. You may examine a place and find it quite clear, or you may find that you are not justified in firing a shot at all. The issue of gas is a very uncertain sort of thing. 5682. Yes; but we are dealing specially with dust P -As a matter of precaution against dust I do not think it important. I have examined into numbers of cases, and it is not necessary for us to suppose for a moment that the great explosions which have taken place, or even the minor ones, were caused by any ignition of dust per se without gas. 5683. (Lord Rayleigh.) Do I understand you to doubt that an explosion might be carried on by dust only in the absence of gas, supposing it were initiated, for the sake of argument, by gas P-I think that very likely the flame might be aided in passing, but that it could not go, as I have heard opinions given, for miles through workings, not any amount of flame as flame. I think the greater the amount of gas you have, the greater the amount of flame, and the heated air carries the effects so much further; of course the skin is delicate, and the hair is delicate, and the heated air scorches at a great distance. It is not necessary when you find a scorched body to suppose that the flame extends so far as that. I believe that a great mass of flame heats the air up to a certain point, and that you will have the effects extended in that way. It is just possible, as I have just said to the Chairman, that dust aggravates an explosion, but does not explode, I do not know of any fase whatever in which dust alone has caused an explosion. 5684. My question relates to this case. Supposing that there were a long gallery throughout the whole of which therewas dust, but at one end of it only there might be gas, and that the ignition took place at the end where there was gas, do you consider it impossible that that explosion should by means of the coal dust penetrate to a long distance, where there was no gas P -- I sayif you have gas exploding and causing great flame, as I have seen it, then it licks up the dust, and no doubt it continues the flame farther. according to the amount of dust. 5686. Supposirg there was sufficient dust P--If you throw fine dust upon that coal in the grate which is now existing as a fire, then you will have flame. No doubt the flame will be extended by dust, provided there is any quantity. But I may point out that in our roadways, for instance, it is so mixed up with rubbish and dirt of every sort that you can hardly expect it to take flame. The only places likely would be in the upper part of the headings. 5687. We have it before us in evidence that there are galleries throughout which the dust is in a highly inflammable state P-Many of the experiments which have been made are not what you would expectwould occur in a colliery; for instance, the early experiments upon the subject, in which you had the finest dust provided for you, and fired a cannon into it, and all that. I hardly think that anything of that nature, will do; you must have something similar to what would cccur in a colliery. 5688. But surely there can be no better initiation for an explosion than the ignition of gas at one end of a gallery P-I admit the gas, and that the effects of the gas exploding are aggravated by dust. 5689. But that is to say, aggravated only where the gas is. My question was whether the explosion might be carried by the dust to a great distance from the place where there is no gas P-.-After the gas has exploded P E2 836 Mr. B. Bedlington. 4 Mar. 1892. ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES: candle fell on to the powder which they were handling 5690. Yes P-Yes, I say it is aggravated and carried further. just beneath it. That was in past times. The cartridges are not allowed to be made underground now. 5691. But much further P-That is if you get dust; 5707. I think I gathered from you that the conclusion much in the roads, I think it would I do not think so you had arrived at was that in all your experience you be in the upper part of the galleries; the finest dust had never known of a case of a blown-out shot firing would lodge there. As for the roads, it is trodden down coal dust by itselfP--That is so. so much that it is hardly likely to be, but about the upper part of any of the galleries you would have the 5708. Therefore you think such a danger is not to be finest dust lodging. No doubt if the flame extended to feared P-That is so. that, the dust would also be ignited by the flame and 5709. I suppose if there was a single case of such a extend it and carry it further; there is no doubt about thing coming to your mind, that'would alter your view that. entirely, would it not P-If there was such a case. Still 5692. Would there be any limit to the distance to I would say it was such a remote contingency that it which an explosion might be so conveyed by the dust Pwould be hardly fair to make hindrances in the working Yes, from my examination after explosions I could not of the collieries simply because you had had an say that there was any reason to suppose that the flame occasional case of that sort. had extended any great distance. The flame was 5710. Supposing you found a case where firedamp according to the quantity of gas. To tell me that flame in any explosion will be carried a mile or two, as I have was absolutely certainly absent and an explosion took place from coal dust alone, would that alter your view P heard gentlemenstate, is beyond my powers of belief. -My experience would tell me to the contrary, and I for that opinion. They certainly have had no reason have examined into a great number of cases where 5693. (Mr. Bainbridge.) The general effect of your explosions have taken place and there was no reason that coal dust by evidence appears to be that you think whatever to suppose that the explosion took place from . itself in a mine need not be considered a serious danger P dust alone. -Not as a serious danger, except as to the after effect 5711. Are you familiar with the Risca explosion in in a gas explosion. 1882 P-I have heard that matter debated and con5694. I mean by itself in the mine P-By itself, not. sidered, and I cannot say the exact circumstances. I 5695. Is there anything else, as the result of your have been in that pit, and I have been, I suppose, near the place where it occurred, but to say whether I knew long experience in dry and dusty mines, that you wish to bring before the Commission P-Of course, having whether there was gas there or not, I could not tell you regard to its annoyance in the workings, I should think that. I did not examine it at the time; it is the only dust ought to be cleared off the roads and so on; but it case in South Wales that is even mentioned as probably would be a very difficult thing to effect it in every part due to dust. It was on the intake, and I fail to underof a heading. It lodges in the crevices and lodges in stand how there could be much dust there at all. It the top of the timbers and places of that sort, and you was not very far from the pit on the intake, and where cannot reach every place, even where the mines are the dust was to come from to explode I do not know. watered by pipings. It is generally on the main ways I have walked along the place. Of course I cannot definitely say that it did not take place, but still it is a that the piping is laid. doubtful case. 5696. Have you a dry and dusty mine under your 5712. Then do I gather from you generally that in management now P-Yes, most of the workings are dry every case where the evidence has been that, as far as and dusty. one could judge, there is no gas, and yet an explosion has 5697. Which is the most dangerous mine you have to taken place which appeared to be due to coal dust alone, do with P-The most dangerous now P you think the evidence cannot be correct P-It is a mratter of opinion. 5698. Yes, as to either dust or fire-dampP--I could not say that we have any specially dangerous mine, 5713. No, it is a matter of evidence P-The difficlty but nearly all the deep mines now are necessarily dry is to say that there was no gas there. The most probable and dusty. cause of an explosion is gas, and you must bring it 5699. Are you carrying out the precautions of the clearly home that there was no gas there. Now, in some Mines Act with regard to the dust P-Clearing away of the earlier experiments in Germany, there was used a long box with the finest dust. We know that with dust on the roadway P That is what I direct my very fine coal dust gas is readily evolved, so much so attention to. There is no place in which I have adopted that we used to take precautions underground long ago pipings throughout the workings. As I say, there is an objection to watering the roads, that it softens the to prevent heaps of small coal being accumulated in the stratum. I know that in many cases it loosens the workings, because the smaller the coal is the more readily the gas is evolved. timber. It is a very awkward thing to go and soften the fuundations of your timbers. 5714. I would rather put a case of an actual explosion to you. Take a ease like Seaham, Elemor, or Altofts, three very typical cases which have been brought before us here, where the evidence was that there was no trace of gas for hundreds of yards round 5701. What do you do in your own mine with regard the point of the shot; how would you explain that P-It to dust P-We do not do that at all; we do not find it is not within my experience whether that took place. I m only speaking of the experience I have had during the necessary. last 50 years, that is all I can say. What has taken 5702. Not to water them P--in the present state, no. place elsewhere of course I cannot know the ci.rcum5703. Then you adopt the principle of removing the tstances of. People, even after an explosion, have p-Yes, that is what I prefer. dust different views of how it took place and where it took 5704. And not watering P-Yes, I prefer taking it place; that is the result of my experience. away. 5715. (Sir William Lewis.) What would you require 5705. What is your experience of explosives; are you to convince you that an explosion might be created by using gunpowder ?--The colliers use a variety. Some dust alone P-I would say this. Take a coal in which keep to gunpowder, others use compressed powder, some no explosive gas has been seen for 20 or 30 years, or 100 yearsuse gelatine, and some dynamite when they are obliged to rip rocky roofs and so on. 5716. Coal or a colliery P-I knaow such coal in which gas has never appeared at all. 5706. Do you allow the colliers to choose their own explosive P-Of course we would have a veto upon it. 5717. Are you speaking of a coal or a colliery now P We have had no accidents from any of these explosives -I am speaking of a vein of coal from which no gas in the mines I am connected with, but in past times nas ever been seen at all, within my knowledge, and I I have seen powder carelessly handled by colliers. have had a long experience of it. Take that coal and I remember an instance of this sort. We did use crush it ahd make it into small coal, and see whether candles in the old times, you know, and with a piece of you can explode it. clay they used sometimes to stick a candle up on a 5718. Is that what you require to convince you that timber. That was a very convenient thing to them. I remember, an accident occurring to a couple of men it is possible P-Yes, with the dust from a vein of coal who were making their cartridges-that was allowed at in which no gas has ever appeared, then I would be that time-and they allowed the clay to dry, and the satisfied that coal dust, per se, would cause an explosion; MINUTES OF EVIDENCE. that is,' tried under circumstances likely to arise in a colliery. Firing cannon into small coal, and all that sort of thing, is not likely to occur in a colliery. 5719. Assuming a gallery is constructed on the surface, of the dimensions usual in an underground mine, and inside of that you have a blown-out shot, either with powder or with what is described as a flameless explosive, and that the place is covered with dust, and pretty much in the condition that some of our steam coal collieries are in South Wales, and that you had an explosion from that blown-out shot, where there could not possibly be any gas--would that convince, Mr. Bedlington P-With such a condition as I have intimated, that no gas has ever appeared. 5720. This is on the surface, there is no coal there, there is no gas; every precaution is taken that no gas could possibly be there P-It depends on what it is. 5721. We have a blown-out shot among fine dust, dust prepared from any seam you like to mention as being worked in collieries in South Wales, and with that blown-out shot create an explosion, would that convince you as to the possibility of dust initiating an explosion ? -It would convince me if you used a small coal which never produced any carburetted hydrogen. I am telling you of a case of a coal I know, in which no gas has ever been seen. If you go and fire into that a blown-out shot and get an explosion I would say that it was due entirely to the coal dust itself. But, as I say, if you take the gaseous coals you do not know what evolution of gas has taken place from them on the surface. Then again, your gallery must be well trodden down by men and horses, and so on. and you must take only the chance of having a little dust on the top of the gallery. You do not expect me to think that simply on a road which is continually walked over by horses and men, and so trampled down, you are going to have that in the same state as the finest dust. 5722. That is what a colliery is. No; lbut assume the same conditions as are in existence in collieries in South Wales, which bo:th you and I knowkvery well, where the steam coals are being worked, and that there was a blown-out shot at the end of a gallery wh ere every precaution has been taken against the possibility of gas existing, and that you then have an explosion; would that convince you that dust could initiate an explosion underground ?--No, it would not convince me until you use a coal from which no explosive gas issued. 5723. Why should you do; that; why should you use any other coal or dust or any other seam than we are working every day P You know we have a large number of seams that are known to be fiery ; let us have the dust from those fiery seams, and would you then be convinced P-If you do use small coal from fiery seams gas issues from it. 5724. Then it would be doing so every day underground P-You could not distinguish then whether it was from gas or whether it was from dust. 5725. Very well then. Are you not making the admission that it is so underground every day, if that is where the gas comes from. If firing a blown-out shot into dust would initiate an explosion either on the surface or underground under the same conditions, would that not convince you P-Under the same conditions, but your galleries are made for a special purpose, they are spriinkled with nothing else but fine dust, which is not exactly what takes place in a colliery; trample that down ---- 5726. Forgive me, you have not taken notice what conditions I have asked you to assume P-The same conditions P 5727. The same conditions as are in existence in a mine P-I do not think that has taken place in the experiments made as yet. 5728. No, I have not said that. I said assuming that there were experiments under precisely the same conditions as exist in a mine, would not that convince you that an explosion could be initiated by coal dust P-Yes, it would, but at the same time I must say that we must go by the experience of actual working in collieries. If such things take place they would take place frequently. Explosions are infrequent and the causes of them are generally traced to gas. There is hardly a case in which there has been any proof that any explosions have taken place, I am speaking of South Wales, which I know best, in the absence of gas. You have always been able to show that there has been gas. 37 5729. That is, you have been" satisfied that there has been gas P-On the evidence that has been given at the various inquests. 5730. Have you ever seen a blown-out shot in coal dust in a colliery in South Wales P-I have been near one. 5731. A blown-out shot with a flame P--With a flame showing not nearly so far as some people have testified. But I have seen it, will say as far as my recollection we carries me now, and I have been very near one, about four or five yards I should think, mixed up with flame and sparks. 5732. But not much of a flame P-Not in that case, but it was mixed up with some flame, some sparks. 5733. Was that in a dry and dusty place P-Yes, I should say it was. 5734. And the dust had been cleared away P-No, I think not. That was many years ago. I have not seen any blown-out shots recently. It is a very rare case is a blown-out shot. 5735. Was it in a confined space P-It was in a stall. 5736. Was it in the direction of the roadway or was it across P-As far as I recollect it was at right angles from the side, blowing towards the roadway; that is as far as my recollection goes now, it was many years ago, before me now. but I have got an idea cf the p' cee 5737. Into the gob then P-Towards the gob; as I say, I have not seen any blown-out shots in recent years, and altogether it is a very rare event. Generally and then there what we do find is that the shots fail is a certain interval of about 24 hours to elapse before the new shot is allowed to be put near it in order to be quite certain that there is no holding back of the fire. That occurs frequently. Then there is a mark made in the stall to prevent anybody going into that stall till the following day. 5738. You said in reply to Lord Rayleigh that the existence of dust might extend the effects of an explosion, but would you not go further and say that the explosion would extend so far as the dust continued along the galleries P-No, I do not think so, because it must gradually lessen; the flame due to the explosion of the gases would become weaker and weaker. 5739. Then you are not of opinion that it would feed upon the dust as it went along P-No, I do not think from the examination of explosions which I have made that it was necessary to suppose any flame. If you had flame it would fill the whole heading, and everybody knows that after an explosion when you begin to examine the workings you find the scorching is on the one side of the timber and not round the timber; it seems to be next to the main passage. If the timbei is on the side you see one side scorched, but if you had the whole gallery filled with flame you would not find on one side of the timber that there would hardly be any scorching at all. 5740. Have you not been able to ascertain pretty well the extent that an explosion has spread through the workings by the etfect on the timber or the sides or the bottom by charred coal dust P-Yes; but then the question is whether in addition to the flame the air heated to a high degree by explosion does not extend the effects further. It does nort necessarily rfollow that it was flame scorched the place. It may be heated air, for we know that that, of course, will scorch, especially such delicate things as skin and hair. 5741. Then you are still of opinion that it would not extend so far as the dust continued in the gallery?No, if it did that of course it would go through all and every part of the workings, and we have no reason, in the examinations we have made, to think that it was so. I am simply giving you the result of my experience without regard to any particular theories at all. 5742. (Mr. Fenwick.) Have you had any occasion to examine a mine after a large explosion P-Yes, on several occasions. 5743. Did you find on any occasion that there were indications in the mine that the flame had passed over a certain portion of the mine and again showed indications of its existence further on P-I have seen it up to a certain point where we generally expect it would take place. but I have seen the effects of an explosion cease after a certain point. 5744. And recommence again P-No; I have heard of such cases, but it is not within my experience. I E3 Mi-. R. Redlington. 4 Mar. 1892. 38 Mr. R. Bedlington. 4 Mar. 1892. -- - -- ROYAL COMMISSION ON EXPLOSIONS have heard that at an angle or at the end of some particular heading it has leaped over an intervening space. Why that is I do not know; I have heard of such cases, but I cannot say that they are within my own knowledge. 5745. Such a case has never come within the range of your own experience P-No, I should think not. I could trace the passage either of flame or of highly heated air producing certain effects upon the return, but other parts of the workings which would be equally dry and dusty have shown no effects whatever of the explosion, in fact men have come out all right from certain parts. 5746. Are the mines of which you have experience in South Wales considered fiery mines P-I have had to do with fiery mines. FRO(M COAT DUST IN MINES: 5747. And dry and dusty mines P-Yes, all the deep mines will be more or less dry and dusty, because, of course, of the depth. 5748. Are there any in that condition now that you are connected with P-Nearly all the deep mines are dry and dusty to a certain extent, but it is difficult to say to what degree. '749. Do you take any other precaution against an explosion than the removal of the dust P-The removal of the dust on the roads, and then wherever safety lamps are used have regard to the watering in the vicinity of the shot, and the places where the shot is to take place. The witness withdrew. Adjourned. At 23, Great George Street, Westminster. FIFTEENTH DAY. Friday, March 25, 1892. PRESENT : THE RIGHT HON. JOSEPH CHAMBERLAIN, CHARLES FEYWICK, M.P. Professor HAROLD DIXON. Mr. J. WILSON, Secretary. LORD RAYLEIGH. Sir WILLIA Mr. F. Brain. 25 Mar. 1892. M.P., CHAIRMAN. Mr. LEWIS. Mr. FRANK BRAIN called and examined. o5750. (Chairman.) You are a member of the Institute of Civil Engineers, are you not P-I am. 5751. You are also a member of the South Wales Institute of Mining Engineers P-I am. 5752. And you are also on the executive council of the National Association of Colliery Managers F-Yes. 5753. I think you are a manager of a pit in the Forest of Dean P-Yes. 5754. What is the name of it P-The Trafalgar Colliery. ,5755. Is that an important colliery P-It is one of the largest in the Forest of Dean, employing about 750 men. 5756. I suppose you have had large experience of the working of collieries in the Forest of Dean P-Yes. I have been intimately associated with the working of the Forest of Dean collieries for the past 20 years. 5757. Have you read the evidence which has been given before this Commission P-Some portions of it. 5758. Have you considered the question of the influence of coal dust on explosions P-With relation to the Forest of Dean, I have. 5759. Now we have been told that even without the presence of explosive gas it is possible that coal dust may initiate an explosion. What is your opinion about that P-My own opinion is, decidedly not. 5760. I think that the Forest of Dean mines are not explosive mines P-Explosive gas has never been found in the Forest of Dean5761. Has the Forest of Dean been free from explosions P-Quite free. 5762. Are you aware whether there has ever been in the Forest of Dean an explosion caused by dust P--I have made very extensive inquiries on the point, and my own experience is decidedly not, and from inquiries that opinion has been very strongly confirmed. 576.. Are the mines dusty mines P-Some of them. 5'6574. Is shot-firing practised there P-- Yes, very largely, with gunpowder. 5765. Consequently, there are frequently blown-out shots P-Ndt very frequently, but occasionally that would happen. 5766. You have never known, however, a blown-out shot to be followed by any kind of explosion ?-Never. 5767. Has your attention been drawn to an explosion which took place the other day in a Radstock pit, the No. 4 Pit P-I heard a little of it; I think it was Mr. McMurtrie's. 5768. Yes. Do you know that pitP--I have never been down it. 5769. Do you know whether this pit is a dusty pit PI believe so. 5770. In the report that I have it is stated that the explosion in this case was an explosion caused by a blown-out shot P-You refer, I believe, to an explosion which took place some two or three months ago P 5771. Yes, it was from a blown-out shot. The mine is not a fiery mine, is it ?-Not that portion of the mine. 5772. How do you account, then, for that explosion, which I believe traversed about 40 or 50 yards, if it was not a purely dust explosion P-I think 1 should hardly call it an explosion, but rather put it as a prolongation of the flame from a blown-out shot, and taking that view of it, it is strongly confirmatory of my opinion that coal dust, such as is found there, would not cause the explosion. 5773. You do not mean to say that the whole of the explosion or ignition was due to gunpowder P-No; if you will allow me to explain myself, I think it has been proved very conclusively by experiments conducted by Professor Abel some few years ago, both at Wigan and at Chatham, and also by the experiments conducted by the Prussian Commission on this very important question, and confirmed by the experiments conducted by the French Government.-I think it has been proved in all those cases that coal dust alone would not cause ai explosion, at least these were the opinions arrived at by those gentlemen as the result of their experiments, that coal dust alone would not cause an explosion; but where a flame is given off by the firing of a shot of gunpowder such as was the case with this blown-out shot at Radstock, that flame would under certain conditions ignite the surrounding coal dust and would be considerably elongated as a consequence by the addition of the flame in the coal dust, to the flame given off by the blown-out shot. MINUTES OF 5774. Then when you say that coal dust will not initiate an explosion, you mean that it will not spontaneously ignite, but there must be a flame in order that ,j should ignite P-What I mean is that it is not possible for the coal dust to carry on the explosion to any great length; that it may add additional fuel to the fire given off from another cause for a few yards, but that it dies out at a short distance, comparatively speaking. For instance, with reference to the Radstock explosion, from the information given me, this particular place was dry and dusty; the flame from the blown-out shot appears to have ignited the coal dust immediately surrounding the place, and the flame was carried some few yards along the face of the coal, but a comparatively few yards only, although there was found an abundance of coal dust for hundreds of yards further on. If the coal dust itself had been sufficiently dangerous to give off an explosion, I am at a loss to know why the flame was not carried on more than a few yards. Why was it not carried on all along that face of coal, because there would be ample contribution from coal dust in that immediate vicinity to carry it for 100 or 200 yards, as the case may be ? 5775. How far would the explosion from the blown-out shot alone carry, supposing there had been no coal dust there at all -- That would depend upon the position of the shot, and the quantity of gunpowder in the hole, and the amount of ramming upon it, and various conditions ; but broadly speaking you may say, 4 or 5 feet, or 6 feet perhaps. 5776. Well, this explosion was carried on for 40 or 50 yards P-I am informed that it was about 30 yards. 5777. Professor Dixon says that a man was burnt at a distance of 30 yards and the explosion went beyond that P-Perhaps it may have been. I am quite willing to take that view of it. 5778. Might not the fact that it stopped after going 50 yards be accounted for by a damp place or by a siding in which there did not happen to be much coal dust P-I very closely inquired into that point because I saw the importance of it, and I was assured by the gentleman who has charge of the mine that there was abundance of coal dust at the extreme points to which the flame was traced, and that there was no damp whatever, and that the conditions for carrying flame were quite as favourable at the last point where the flame was found, as at the first point at which the flame commenced. 5779. Is the Radstock Pit a pit in which there are stone workings P-I believe so. 5780. Would not the presence of stone dust with the coal dust make it less explosive than if it were pure coal dust P--That may or may not be. 5781. If the dust happened to be mixed with stone in certain proportions that would stop the explosion, would it not F-The experiments conducted, I believe, so far as my knowledge goes (which perhaps is somewhat limited on this matter, so I speak with deference), but these, as I follow them, vary ,ery much on that point. Under certain conditions it has ,een shown that the presence of stone dust has a tendency to stop the explosion as you now suggest; but by other experiments it has been shown that stone dust in considerable quantity, I think even to the extent of more than one-half the mixture, has not interfered with the violence of explosions from coal dust. 5782. What I want to put to you is this, that the fact that an explosion so carried on without gas for 40 or 50 yards further than it would otherwise have gone, is a proof that coal dust can very considerably prolong an explosion, and the fact that it did not go still further might be accounted for by the exceptional condition of the dust on the road in that place P-I should like to point out that there was not a roadway where this dust followed, so that there would not be any great amount of-fine dust ground up constantly by the passing of the workmen and horses, and things of that kind. But this 'was a new coal face being moved forward, and therefore the d4bris whatever it may be that was scattered upon the floor would be quite fresh, and certainly would not be ground up in the way you would apprehend the dust would be ordinarily in a travelling way. 5783. But if it were not fine dust, and not ground up so as to be very fine, it would be less liable to explosion than fine dust would have been P-But allow me to point out -that the dust certainly elongated the flame of the blown-out shot and was exactly similar in character 39 EVIDENCE. to the dust at the point where the explosion ceased, so .Mr.F. Brain, far as I am informed. 5784. But I understand that the very fine dust is much 25 Mar. 1892. more explosive, and gives rise to a much more violent flame than the coarse dust, and if that be the case the flame in the p:resen instance might not have been of sufficient force and violence to go very far -Of course the coal dust that was on the whole of this length of roadway and on the face of the coal where the men were working the coal, the coal dust would be similar in character the whole face through, and I fail to see if the coal dust was sufficiently fine to carry the flame 30 or 40 yards, as the case may be, why it should not carry the flame 100 or 150 yards, provided the theory which is advanced by some gentlemen is correct. 5785. The theory does not amount to a positive statement that in all cases it would go far, but only that it might go far ?-But against that theory I have to again draw your attention to the fact that this is an isolated instance; that in this instance it did stop at certainly the outside 50 yards; that that is an instance out of millions of shots that have been fired in that and other collieries for many years past, and against that one instance, we have to show the fact with reference to the Forest of Dean itself, that we can never trace the slightest explosion whatever. 5786. That would go to show, would it not, that the risk was slight, but it would not go to show that there was no risk, because one affirmative is more powerful than a great number of negativesP-Of course, my own opinion is that the fact of the blown-out shot flame being elongated to a limited extent is very different from the fact that some gentlemen seek to establish, that coal dust itself will cause an explosion which would extend over a. whole colliery. I should like again to refer to the experiments that have been so exhaustively made by Professor Abel, the Prussian, and the other gentlemen, where they show that the utmost limit that coal dust alone would carry a flame, I think, is 70 feet. Their experiments have shown that a blown-out shot flame with coal dust suspended in the air in a very large quantity, of an explosive mixture, ard in the complete absence of gas, would undoubtedly elongate the flame of the blown-out shot, but that to such a limited extent, that in their opinion the coal dust was not to be considered as dangerous, and causing explosions in mines. 5787. You are acquainted, are you not, with the Prussian experiments; you have followed them P-The Prussian experiments were made some years ago, I am afraid. 5788. In that case the gallery was nearly 200 feet long, was it notP--I am sorry my memory will not carry me as to that particularly, but I have no doubt that it was as you state. 5789. You may take it that it was something of the kind. Are you aware that on one occasion an explosion was brought about in that gallery of the coal dust alone, which not only carried the flame to the (nd of the gallery, but blew out some heavy trollies at the end of the gallery, which shows that even at the end of the explosion there was a tremendous force P-Are you referring to the experiments of the Prussian Commission in 1884 ?P 5790. I think so P--Well, I cannot say, but I can state what the words of the Commissioners themselves were: " In complete absence of fire-damp" (which is our condition essentially) " the elongation or propaga" tion of the flame is generally of limited extent, " however far dust deposits may extend, 70 feet being " the maximum." Those are their own words taken from the report. 5791. Well, I will only ask one more question, I will put it that if in the Radstock Pit the explosion continued for 50 yards, do you think it would be impossible for it to continue beyond P-That is my opinion, so far as I am informed at the present time from experience. 5792. What is the difference between the circumstances which allow of it being carried 50 yards, and prevent it being carried 100 yards; why should the same circumstances which carry it on 50 yards, not carry it on 100 yards P-Of course it must be apparent that when the blown-out shot liberates itself, instead of doing the work which it ought to do, the flame that is given off at the moment of explosion, must be a fierce one, and necessarily there must be a great amount of' heat at that particular moment; that great E4 40 ROYAL COMSISSION ON EXPLOSIONS Mr. F. Brain. amount of' heat would undoubtedly, under favourable conditions, ignite certain classes of coal dust; and the 25 Mar. 1892. heat would spend itself by the time it got a certain distance, more or less, according to circumstances. 5793. Yes, but the heat of the blown-out shot would not reach 50 yards, and could not account for the ignition of the coal dust 50 yards off. The heat of the blown-out shot no doubt accounts amply for the ignition of the coal in the immediate vicinity PYes. 5794. But the coal dust at a distance, say, of 30 yards, must have been ignited by the heat of the coal dust behind it; and if that be so, why should not in its turn, the coal dust 30 yards off, ignite the coal dust of 50 yards, and the 50 yards ignite the coal dust of 70 yards, and so on P-Of course, as you very properly say, the flame from the blown-out shot undoubtedly ignites the coal dust in the first instance; the heat from the blown-out shot would carry itself necessarily before it was spent, some distance, much further than the flame would carry; and my point is this, that the coal dust itself in the entire absence of gas (such as are the conditions existent in the collieries of which I have experience) is not a sufficiently explosive element to carry the flame to any appreciable extent apart from an outside element which is brought in to help such as would be in the case of a blown-out shot. 5795. You have been asked. I think, to represent the views of the colliery managers generally in your district, have you not P-I have. 5796. Have you any resolution from them P?-I have a copy which has been sent to me. I do not know whether a copy has been forwarded to the secretary of the Commission. 5797. Will you state what their views are P-Shall I read the whole of the document P 5798. In the first place, what do they represent .- Tf I read the document it will explain the whole thing. 5799. Will yoV do so if you please P-" A general " meeting of the managers of the Somersetshire, " Bristol, and Dean Forest collieries, was held this " day" (on the 15th of March last), " for the purpose of " considering the question of coal dust in the non-fiery " seams of these collieries, and Mr. W. N. Atkinson's " report thereon, and the following resolutions were " unanimously adopted. (a.) The dust in the non" fiery seams of Somersetshire, Bristol, and Dean " Forest will not per se cause an explosion, and has " never been known to explode. (b.) If any experi" ments are made with the dust from these seams, " those conditions should approximate as closely as " possible to the natural conditions of the workings of " the collieries from which the dust is taken. (c.) One " or two managers or mining eulgineers, nominated by " the managers of the above-named districts, should " " " " " " " be present during such experiments. That Mr. J. McMurtrie and Mr. Frank Brain be empowered to represent the managers of the abovenamed districts in giving their evidence before the Royal Commission, and that copies of these resolutions be sent to them.-Donald M. D. Stuart, Chairman." 5800. I suppose then that you would say, and these gentlemen would agree with you, that the ignition of coal dust in the Radstock Pit was not an explosion P-It was not an explosion. 5801. At the same time, I suppose the ignition of coal dust under these circumstances might be the cause of serious danget P-Which we think is amply met by the present law. 5802. By what provision in the present law do you think that danger is met ?-P-The general rules I believe, I have not the Act with me, but it is the set of clauses referring to coal dust in mines. 5803. (Sir William Lewis.) You mean as to the watering P-As to the watering. 5804. And the condition of the place before the shot is fired P-And the condition of the place before the shot is fired. 5805. (Chairman.) You think watering is desirable, although the danger is so slight P-I certainly do not, so far as the Forest of Dean is concerned. 5806. But you referred to the general rules, and I understood you to suggest that they ought to be carried out P-Not put in force, Oh, no! There is FROM COAL D)IT IN MINES: already sufficient power given to the Government inspectors if they deexn it necessary to enforce the regulations, which would be ample in all cases that have come before my notice so far as regards this district. 5807. Yes, but then do you mean that you consider that in those districts it is not necessary to put those regulationis in force P-I think not. 5808. I understand you to say that you would take no extra precautions of any kind against coal dust in this district ?-So far as the Forest of Dean is concerned, decidedly not. 5809. In.the case to which I have been calling your attention a man was burnt; he might have been killed by the same explosion might he not P-Well, of course, I could not say not knowing the full circumstances. 5810. The mere fact that he was burnt is a proof that his life was more or less in danger ?-Certainly. He was injured, I suppose. 5811. Would not you consider in such a case as that, it would be desirable to take the precautions indicated by the general rule P-I understand as a matter of fact, that the Government inspector has not ordered these precautions to be taken in that particular instance. 5812. Yes, but I am asking for your own opinion P-I think not. 5813. You think it would be unnecessary. Do you think that any precautions are necessary in respect of shot-flring in your district?-I think not; none other than we are at present observing. 5814. What precautions do you observe P-We take every possible care that the proper placing, of course, of the shot holes is enforced upon the men. 5815. You do not consider it necessary to prohibit the use of gunpowder in your district P-Certainly not. 5816. Do you use flameless explosives P-None whatever. 5817. What is the advantage of using inflammable explosives; is it cheaper than non-inflammable P-Somewhat cheaper. 5818. Is that the only advantage, or is there any other advantage in the working of the mine P--Of course, as has been said, there is a great difference of opinion but under certain circumstances, gunpowder may do its work better than other explosives. 5819. I think you have some system of your own to which you have given special attention in connexion with blasting P-Yes. I have made quite a study of blasting, with a view to supplant the time fuse by an electric fuse, and the system has been very largely adopted in many parts of the country. I think I masy say it has been found to answer admirably. 5820. What is the advantage of it P-There is no tendency in the first place to miss shots, miss fire; occasionally the time fuse hangs fire as we call it, and it has been known to go off after hanging fire, a considerable time afterwards. Then, further, of course, the flame of the lamp has to be used to ignite the time fuse, which introduces a further element of risk; and further, the time fuse has been known to flame under certain conditions which, of course, in gassy mines would be dangerous. When electricity is used there is no possibility of a flame whatever; it is simply an electric spark passing from a small machine along an insulated wire right into the heart of the explosive and firing the detonating cap, which would be fixed near the explosive. 5821. I suppose such a system as that is more necessary in fiery mines than in your mine ?-It refers entirely to fiery mines. There is no necessity for it whatever in our mines. 5822. Is there any other matter that you wish to speak about P-No, I cannot think of anything at present. 5823. (Professor Dixon.) Do you pass a spark by the detonator in your apparatus, or heat a small piece of platinum wire P-In some instances we heat a small piece of platinum wire, and in other instances we heat what answers to the platinum wire-a small quantity of explosive compound between the two wires of the blattery. 5824. You pass a spark P--It would not be a spark because the explosive would have sufficient conductivity MINUTES OF EVIDENCE. to allow a current of electricity to pass through, and yet not conductive enough to allow that current to pass through without heating. 5825. That was the reason I asked the question. I thought it would be dangerous to have a spark passing. You quoted just now the conclusions by Mr. Hilt, principally with reference to the experiments at Saarbrucken in 1884. Were not these the words you quoted " The presence of coal dust in more or less " abundance in the immediate vicinity of the working face gives rise to more or less considerable elongation of the flame projected by a blown-out shot whether " small quantities of fire-damp be present in the " surrounding air or not P"-Are those words you are quoting taken from the Accidents in Mines Commission Report P 5826. These words are quoted from that report; are not they the same words that you quoted P-The words are different from those I read : " In complete absence of " fire-damp the elongation or propagation of the flame is " generally of limited extent, however far dust deposits " may extend, 70 feet being the maximum " P-Quite so. 5827. I have got that. I will read the second clause. " In the complete absence of fire-damp the elongation or " propagation of flame is generally of limited extent " P -Quite so. 5828. "However far the deposits of dust may extend in the mine-ways" P-That is so. 5829. You quioted that sentence just now and you said that the Prussian Commission came to this definite conclusion, I understood you P-Yes. I understood that to be the judgment of the Commission. 5830. I ask you then to read the next paragraph in the conclusions of the Prussian Commission, which says, " There are, however, certain descriptions of coal dust "' which, if ignited by a blown-out shot, will not only con" tinue to carry on the flame even to distances extending " considerably beyond the confines of the dust deposits, " but will also give rise to explosive phenomena or " results in the complete absence of any trace of fire" damp, which in character and effects are similar to " those produced with some other dust in air containing " 7 per cent. of fire-damp." That is the next para. graph in fact in the conclusions of the Prussian Commission. Have you taken that paragraph into consideration in giving your statement just now to the Commission ?-1 base my remarks mainly upon a further view they gave. They say a considerable distance (they do not mention the distance), but I have it here if, I have copied it correctly, from the Accidents in Mines Report, that 70 feet was the maximum at which flame was found. 5831. I think that must be an error. I have it here in one case where dust was strewn for a length of 130 feet. "The flame was projected 16 feet beyond the " length, 167 feet of the gallery, or at least 185 feet in " all." That is from the Prussian Commission P--I accept the correction. 5832. You have not considered that ?--No. I am still at a loss to know where I got this 70 feet as being the maximum. 5833. That must be an error; the gallery in the Prussian Commission was 167 feet long P-Yes. 5834. And the flame blew out at the end, 16 feet beyond it ?--In the entire absence of fire-damp P 5835. Yes. Would you in such a case as that state that that was an explosion or merely an elongation of the flame P-I think those conditions would almost carry out the suggestion referred to by Mr. Chamberlain, at Radstock. Fifty yards, I think, was the total number of yards, and that would be 150 feet, and this 167 feet would be practically the same. 5836. Would you call that an explosion or an elongation of the flame P-An elongation of the flame, aided by the coal dust. 5837. You have not visited the pit at Radstock, have you P-No. 5838. Do you know whether the flame was elongated in the direction in which the shot blew out, or in the opposite direction; do you know the direction with regard to the long wall P-I have been informed that it was not in the direction the shot was placed. 5839. No, it was quite opposite; the flame went opposite to that in which the gas blew out P-I think it was in the direction of the air current. E 82480. 41 5840. You have not visited the pits, so that you iMr. F. Brain. could not say whether they are dusty or not P-I could not. 25 Mar. 1892. 5841. in your own pits are they dusty along the long wall P -In my particular colliery, not. 5842. You work long wall, do you not ? -Yes. 5843. Are the roads dusty P-Some of them are; but I should not call mine a dry and dusty mine. 5844. Is it damp P-It is somewhat damp. 5845. Have you occasion to fire shots in the roadways P-Occasionally. 5846. There the dust is damp P-It is naturally somewhat damp. 5847. So that you have not had the condition in your own mine which is referred to by Mr. Atkinson as a dry and dusty mine P-Not to the full extent, perhaps. 5848. (Mr. Fenwick.) I think you, in answer to the Chairman, seemed to attach some importance to the suggestion that the prolongation of the flame would have some relation to the strength of the charge; are you accustomed to fire shots in the roof in the stone for roadways P-In the roadways, yes. 5849. Are any of those shots at times fired near to the working face P-Yes. 5850. Would there be any quantity of dust near to where those shpts were being fired P-In this particular instance, at Radstock, it was close to the working face; it was at the working face. 5851. It was in the coal P-Yes. 5852. Radstock presented an instance of working the long wall P- Yes. We also work the long wall. 5853. And the air current was travelling along the face; was it a square face ?-It was somewhat of a semicircle. The face would stand round from the heading. 5854. You seem to doubt that the prolongation of the flame may be carried to any very considerable extent, but, following up the question put to you by the Chairman, would you consider that the flame from the dust once commenced by the flame emanating from the blown-out shot would gather in a gallery that is strewed with finely divided coal dust, would gather up fresh fuel as it comes, and then intensify the heat P-In the districts with which I am associated my opinion is that it would decidedly' not. 5855. But in the case of the Radstock, do you think that it would have a tendency to do so there P-I think decidedly not; and that incident mentioned has corroborated my opinion. 5856. What are the depths of the collieries working in the Dean Forest P-200 and 300 yards. 5857. (Sir William Lewis.) Have you ever seen a blown-out shot P- Well, I have seen one or two, but it is very occasionally we have them, and, of course, I am not constantly in the'workings. 5858. But would you then say that the effect of a blown, out shot would be limited to five or six feet, as you did in answer to the Chairman ?-Decidedly not. I think I qualified tbat. 1i intended to say that it depended so much upon circumstances. 5859. But you said that the flame would be only five or six feet. Do you speak from what you have observed, or from what has been represented to you by those who have seen a blown-out shot P-M-ore from what has been represented to me than from my own experience. 586Q. You have open lights in the Forest of Dean PWe use candles and lamps entirely. 5861. At Radstock do you know what was used P-I believe partly lamps and partly open lights. 5862. Do you know whether gas has ever been seen in any of the measures that are being worked in those pits at Radstock P -In some of the measures I believe gas has been found. 5863. But you have never seen any gas in the Forest mines P-Never. 5864. Could you tell us whether there was any indication of disturbance at the point where this man was burnt, or was it simply an inflammation up to that point P Were the timbers knocked out, or was there any indication of a disturbance extending as far back as F ROYAL COMMISSION ON EXPLOSIONS Mr. F. Brain, where the man was burnt P-I think I am right in saying that thefre was little, if any, disturbance whatever. .5 Mar. 1892. :5865. Do you suggest that the shot blew out, and that the flame in connexion with it was carried with the air in the direction of the current, that it inflamed the dust and continued to burn up to where this man was, and nothing else P-I think so. 5866. There was no force whatever P-Force-yes, because, as I understand the position of the shot, it was near to a doorway which was directly facing the point at which the shot was put in. 5867. Would you mind making a sketch showing the position of the face and the direction in which the shot blew out P-My information is subject to correction. I can only do it from memory and from what I have been told. (The witness drew a sketch and proceeded to describe it.), This represents the face of the coal; the air current was travelling up the face. There was a doorway, I cannot say whether it was 14 or 15 yards back from the face, but it was somewhere here, opening this way. 5868. Was it towards the face P--Yes, towards the face; the direction of the shot, I cannot say, but I fancy it was put in a little like that. 5869. Then it was almost at right angles with the face at that point P- Yes. 5870. At all events at right angles with the current P -Yes; the man, I believe, that was burnt was somewhere in bye-side; there were other men along here, a very few yards away at the other side of the door. The explosion extended from this point to somewhere here, I cannot say exactly where, and then it died out entirely. What I meant in referring to the blowing out of the shot would he the fact that necessarily with the large explosion such as would happen in this instance (because 1 understand thatthe charge was entirely blown out and failed to do its work) there was very considerable flame; the air here would naturally be compressed in tiat very short distance, and therefore that would add to the extent of the explosion in carrying it around that face. That would necessarily be the only outlet unless it went against the current which would be the line of more resistance. The line of least resistance would be to pass up the coal face in the direction of the air current. 5871. Do you suggest that this was the line of least resistance when you have an opening here nearly opposite where the shot blew out, and simply by the blowing down of this door that would be the direction by which the force of the explosion would be naturally expected P-Yes. b87 2., Was, that so or not P-I say that my opinion would be that the line of least resistance would be the open face rather than blowing down the doorway opposite the shot. 5873. The line of least resistance at right angles with the actual direction of the shot hole P-Under the circumistances Which I state the door was not injured at all. Men working along here never knew that an explosion, FROM COAL DUST IN MINES: 5878. Then the force must have been there a slight ('1eif a 6-foot door would resist it P-Some yards away, 15 yards away. 5879. But in the direction and almost opposite to the blown-out shot P-That is my opinion. 5880. Following that point you simply suggest that the flame given off by this blown-out shot inflamed a quantity of dust at this point that was carried by the current and continued to inflame the dust up to 30 or 40 yards and there it spent itself P-That is so. 5881. Is that what you would have expected if you had similar circumstances, say in the Forest P Would you have expected that same result P-Of course, it is a most extraordinary incident. We have never had such an incident, so far as I can gather, in the Forest. 5882'. You do not know the difference between the Forest and this place sufficiently well to give any opinion upon that point P-No, I could not. 5883. At all events, assuming that dust will not initiate an explosion, it is desirable, to say the least of it, that some arrangement should be made by which such accidents should be prevented from blown-out shots. You would go to that -extent, would you not P-If they were occurring in the Forest of Dean, I should say so. 5884. Yes, but occurring anywhere. This would indicate that there is a danger arising from having blown-out shots where dust does exist in the face of the mine ?P-A very limited danger. 5885. But still a danger ?-Oh, yes. 5886. With that knowledge you are still of opinion that if the provisions of the present Act of Parliament are perfectly carried out there is no necessity for further legislation P-I do not say that generally. I am only speaking with reference to the characteristics of our own district. 5887. Then you do not give us any opinion upon mines in general P-Certainly not. I prefer not entering into that. 5888. You have had no experience in our South Wales collieries P-None whatever. 5889. And you do not find it necessary to put in force the provisions of the Mines Act P-We do not with reference to this particularly. 5896. And you' do not find it necessary to water PNo. 5891. Nor do you fixnd it necessary to clear the dust before firing the shots P-No. I wish it to be distinctly understood I give my opinion only with reference to the Forest of Dean. 5892. Are you in the habit of setting off more than one shot at a time in the Forest P-Not usually. . 5893. Would you consider that attended with danger even in the Forest P-We have never considered it so; we should do so if we required it. 5894. From your experience in shot-firing, would you think it possible with one shot raising the dust that the next shot afterwards might inflame it to such an extent if it might be called an explosion, had happened. as to be the cause of a serious accident P-I do not think : 5874. Does not that go directly against your theory, so in the Forest of Dean. and is it not entirely in favour of dust being the 5895. (Lord Rayleigh.) I do not quite understand the cause of the explosion. Once created and carried along distinction that you seem to draw between the explosion with the current this way, would you not have expected of coal dust and the mere inflammation of coal dust. to have found indications immediately opposite and in Can you explain that further P-I am afraid I am somethe direction of the blown-out shot, instead of finding it what at a loss to know how to explain it further. at right angles with the blown-out shot, and carried 5896. Do you think there is any distinction P-What along here for 40 yards P-As I before remarked, I think that the flame from the blown-out shot compressed the I wish to convey is, that the coal dust under certain air here, raised a cloud of dust, and that cloud of dust conditions may help to feed the flame given off by the blown-out ashoet, but only to a limited extent. was set on fire and went with the force of the air 5897. Take this case which has been mentioned at current along the face. Radstock in which, in your phrase, the flame of the 5875. Would not you expect that door to be blown out and find indications all the way down the heading P blown-out shot was elongated by the aid of coal dust up to about 50 yards; supposing that that elongation You have told us that the shot blew out and it must had occurred to 500 yards instead of 50 yards, would have been a pretty severe concussion P?-Yes. you still have considered it an elongation of the original 5876. And you would expect indications of dis- flame P-Certainly not. I should say that is an exploturbance, to say, the least of it, immediately opposite sion of the coal dust. and in the direction in which the shot was blown out P5898. I think that the door-it was not a brattice, it was a depend Therefore what you call an explosion would upon the extent to which the inflammation strong door-being placed at that point, so nearly to extends P-Yes, because in the second instance it is the face, caused' the compression of the air as I said, and the line of least resistance was the coal face, and quite apparent that the flame of the blown-out shot would have been utterly exhausted long before it it passed along there. had gone 50 yards, much less 500 yards, and there5877. In order to have a compression the door must fore the coal dust itself must have been sufficiently be of greater strength than the force exerted by the dangerous to have carried on that explosion the distance bldonout shot P-Decidedly. you name. MINUTES OF 5899. Does not that amount to saying that there is no real difference between the explosion and the inflammation. If the inflammation occurred on- a sufficiently large scale you would call it an explosion, and if it were on a small scale it would be inflammation ?-I hardly agree with you. 5900. How would you put it P-I would say that the very limited extent to which coal dust in the entire absence of gas has up to the present time been shown to carry a flame is not sufficient to justify the conclusion being come to that coal dust of itself, and.of itself alone, will produce an explosion such as the one you have now drawn my attention to as an example. 5901. In spite of the fact that the inflammation extended in this case to 50 yards you think it is quite safe to assume that it could not be spread to 100 or 200 yards P--Speaking with regard to the Forest of Dean we have never had one to the extent of 50 yards even; and even with the experience before me of the one you name extending to 50 yards, I do not think even with that experience that is sufficient to alter my opinion. 5902. Would not you go so far as to admit that it is rather a nice matter whether or not an explosion, in thefull sense of the term, will result when the flame can extend to so great a distance as 50 yards from the source P--If that be so, I ask why in districts such as this, where in all our collieries, some of which have been reported upon by Mr. Atkinson as being dry and dusty, where we are firing thousands of gunpowder shots in the year, why is it that we have never had the slightest experience of an explosion P 5903. But is not it a fact that your mines are not dry and dusty P-Some of the mines were reported by Mr. Atkinson as being dry and dusty, and others as not being so. 5904. (Sir William Lewis.) I observe in this memorandum, which is signed by Mr. Stuart, as chairman of this meeting, that the opinion was intended to be conveyed with reference to the "non-fiery seams" of Somerset, Bristol, and the Dean Forest. I would infer from that. that the same conclusions would not hold good with respect to the fiery seams in that coalfield P -That is so. On that point there is a great difference of opinion amongst these gentlemen. 5905. I think that is important. Now, are you in a position to speak for those districts with reference to the fiery portion of the strata in Somersetshire, Bristol, and the Dean Forest P-I am not. 5906, You are aware that in Radstock and other collieries some of the seams are highly charged with gas P -- I believe so. 5907. And we are not to take your opinion as expressed here to-day as applicable to those districts P-Not the districts charged with gas, certainly. Primarily I represent the Forest of Dean, in which there is an entire absence of gas. 5908. My attention was only called to this after I saw this document P-Certainly, the mines in the Bristol and Somerset districts, so far as the mines in these districts are concerned, that have no gas in them. 5909. But you would draw a distinction, and a very important one, between the fiery seams and the nonfiery seams P-I should, a very important one. 5910. (Chairman.) I omitted to ask you a question or two in regard to the resolution which you have read, and which refers to possible experiments. In this resolution it is said those experiments should be approximated as nearly as possible to the natural conditions existing in the collieries. Will you explain what you consider would be an approximation in an EVIDENCE. 43 experiment to the natural conditions of the colliery, Mr. F. Brain. How do you think that that approximation should be 25 Mar. 1892. Mar. 1892. secured P-I am afraid I am hardly competent to suggest: to you gentlemen how to do that. 5911. I assume the matter was discussed by the meeting of managers ?-Well, we arrived at no definite conclusion in that matter. I simply give it as an expression of our opinion that the best possible form fQr those experiments should be adopted having that idea in view. I may say, speaking personally, that it has struck me that it would not be difficult to build up on the surface a chamber corresponding to a roadway, and a coal face such as we should have in the Radstock district or in our own district, and to place on the sides of that chamber dust taken from our various pits, and thus the experiments could be conducted in the chamber with the dust taken from our collieries. 5912. What size should the gallery be P-I should put it as an exact fac simile of the roadways in the mine. 5913. But the roadways in mines differ very materially especially in mines in different parts of the country PWell, I think it would be perhaps not unwise to take as a model the special district that has been referred to this morning in the Radstock Coalpit. 5914. But supposing we were to take that, do you imagine that that would satisfy persons in the Lancashire coal district or in the Scotch coal district P-I could not say with reference to those other districts, but only with reference to our district. 5915. In order to have a satisfactory experiment are we to have: an exact model of every mine or of the mines in every district P-Certainly not. 5916. What I want to know is, of course, what are the conditions which you regard as imperative. For instance, what ought to be the length of the gallery PAs long as you can possibly get it, the longer the better. 5917. What would you consider a satisfactory length, a conclusive length P-If it could be got, say 400 or 500 yards. 5918. And what size; what would be the size of the roadway of which you speak P-The ordinary roadway would possibly be 6 feet by 7 feet perhaps. 5919. Are your managers determined to receive no experiment as satisfactory which is not carried out in a gallery 400 or 500 yards long on the surface and 6 feet by 7 feet in size P-Allow me to say, what I think I have already stated, that we arrived at no conclusion as to the final directions which the experiments should take, and you pressed me still further, and I then ventured to give a personal expression of opinion, which has not been considered at all by the managers as a body. I do not think for a moment that our managers would not be satisfied with whatever the Commission thought would be a satisfactory chamber for such a purpose. 5920. I understand then that in passing this resolution the matter was not discussed in any detail PNot at all. We desire to approximate as nearly as p)ossible to the natural conditions of the mine. us 5921. (Sir William Lewis.) And in order to satisfy you. you would require that experiments should be made with dust, gay from the Dean Forest, a certain set of experiments from the Bristol coal fields, with other experiments from Somerset and from the various other coal fields P-Yes, those coal fields with which we are associated. 5922. And without that you would not be satisfied that dust can initiate an explosion in a mine P--Certainly not. We are strongly of opinion that with regard to our special district we cannot get an explosion in a mine. : 'The witness withdrew. Mr. WILUIAM WALKER HOOD called and examined. 5923. (Chairman.) You are the general manager of the Glamorgan Coal Company P-I am. 5924. Have you given any attention to the question of the action of coal dust in mines exliosions P-Yes, I have for a number of years, in fact ever since Mr. Galloway carried out his experiments at Llwynypia. 5925. What conclusion have you arrived at on the subjectP--That coal dust is inflammable without the presence of gas, other than that contained in itself, . 5926. I suppose in order to set up the inflammation thore must be omething in the nature of an explosion P -No, not necessarily. 5927. Do you think that it would explode or inflame by simple contact with the heat P-Yes. 5928. With even an open candle P-No, I do not think that a candle has sufficient flame to do it. 5929. What are the ways in which you think that ani explosion might be initiated P-Well, if I can give an F2 Mr. W. W. Hood. 44 ROYAL COMMISSION ON EXPLOSIONS SMr. W. W. example, the cleanings of the mill where we prepare the coal for coking, that is to say, a very fine flowery coal, Hood. when that is thrown into a coke oven the bricks of 25 Mar. 1892. which are at a dull red heat you will find that the dust ignites or explodes, and the flame comes out of the oven for a distance of 6 or 8 feet. 5930. There must be, in your opinion, a very considerable body of heat in order to ignite the coal dust P -Yes, there must. 5931. Do you think that a blown-out shot is sufficient for the purpose P--Yes, a blown-out shot of gunpowder. 5932. Do you think that that would be sufficient to set up an explosion of coal dust 0-I think so. 5933. Without gas P-Without gas. 5934. And once set up do you think it would be continued P--Undoubtedly. 5935. Indefinitely P-Indefinitely, as long as dust exists. 5936. Have you bad any experience in explosions which have confirmed your views P-Yes. 5937. Will you state them P-The Pen-y-Graig, or Naval Colliery, that was a very dry and dusty mine. I am of opinion that that occurred by a gunpowder shot firing some gas, which ignited the dust and carried the flame into every portion of the colliery. It was fiercer on the main travelling roads where the areas were greater and the dust finer. 5938. You do not think that the continuance of the explosion could be accounted for by gas P-No, certainly not. 5939. Why not P-Because there could not be any gas at the bottom of the down-cast shaft with such a current of air passing ; and blowers, in my experience. although they come siddenly, do not go away suddenly. 5940. You would have expected to find traces afterwards if there had been blowers P-We should have expected to see gas in the workings. With the diminished quantity of air travelling after that explosion, due to the ventilating apparatus being damaged, the cap on the safety lamp was barely half an inch, that is, at the bottom of the upcast shaft. 5941. Are there any other instances which you wish to give P-Well, at the National Colliery there was an explosion in 1887; the spread of that explosion was stopped by water on the roadways at the bottom of the downcast and also at the bottom of the upcast shafts. .5942. You think that was a dust explosion P-Certainly. 5943. Holding this opinion, I suppose you consider that the presence of dust is extremely dangerous if predautions are not taken against it P-Yes, it is. 5944. It might cause an explosion, and it would be likely to increase the effects of an explosionPYes. 5945. Do you think it necessary to take any additional precautions to those which are indicated in the general rulesP--I do not think that it is necessary. 5946. Do you think these precautions are sufficient P -Yes 5947. That is to say, the removal of the dust P-At the parts where shots are fired. 5948. Where you fire a shot and, also, in the main roads where dust accumulates ?P-Yes. 5949. And the watering of the dust P-And the watering of the dust. 5950. But you think that these precautions ought to be observed in all dusty mines P-I do not think that exactly. I think that if 20 yards is watered round about where a shot is to be fired it is not necessary to water all the roads, but I dq it for, the comfort of the men in the mine. 5951. Db you remove the dust P-No, we water it. 'I do not think that it can be removed sufficiently. 5952. For the purposes of safety, all that you think necessary is to water where the shot is fired P-Yes. 5953. What is the practice generally adopted in the South Wales coalfield P-Most of the main roads are watered. 5954. -How P-By means of tanks and by means of jets. FROM COAL DUST IN MINES: 5955. What mode do you adopt yourself P-Jets and tanks. 5956. Both P-Yes. 5957. Which do you prefer P-Jets. 5958. Is the jet system a system of spray P-Yes. 5959. Do you use the system invented by Mr. Martin P -No, I do not; but it is undoubtedly the best spray. 5960. He uses compressed air P-Yes. 5961. Why do not you use that if it is the best PBecause I get very nearly the same result by pressure. 5962. By pressure upon the water P-By pressure upon the water. 5963. Without introducing the air into it P-Without introducing the air into it. 5964. I think Mr. Martin contends that with the air the spray is much finer and extends further, and, altogether, that it has a much better result P-Yes, it has a little better result. 5965. Will you explain the system of water spray P -I put a spray about every 40 yards in the main roads; but even that system of watering is not perfect in dry and frosty weather, in fact, it is impossible to get up the degree of humidity to thoroughly saturate the air with moisture in frosty weather. 5966. Then you can do nothing in frosty weather POh, yes, we can do it partially, but you cannot saturate the air with moisture. 5967. Rave you got any diagrams to show that PI have got diagrams to show it in three different stages, that is to say, the humidity in the air when the jets are idle, and another one showing the humidity in the air when the jets are going, and the surface temperature nearly normal, and the next one in frosty weather. (The witness then describedsome hygrometrical tables.) Referring to Diagram No. 1 of hygrometrical readings of the Penrhys district, the witness stated that the water sprays had been idle, and had not been going for four days previous to those readings being taken; and that all the way round the workings 80 was about the highest humidity that was obtained. 5968. (Lord BRayleigh.) Do you mean 80 per cent. is the possible amount of moisture in the air P-Yes, under those conditions. 5969. Does Diagram No. 1 refer to a'day on which the conditions were difficult to secure moisture P-The weather was cold and foggy, with 88 per cent. of humidity in the air on the surface. 5970. (Chairman.) I see the difference between the two bulbs is four degreesP--Yes. 5971. Part of the roads were damp from the watering having been previously done P-The roads would not be absolutely dry on that day. (The witness described Diagram No. 2.) 5972. Now then, will you explain what it was when the sprays were at work P-That was the most favourable day for it was raining heavily on the surface. The dry bulb was 50 and the wet bulb 49k. I do not show the readings at the surface on the diagram. 5973. And here the two bulbs seem to have been the same, or nearly the same all through P-Yes, excepting the face, where it dries up a little, there is about half a degree of difference between the two bulbs. 5974. Is it practically complete saturation P-It is I do not want practioally complete saturation. the air to be completely saturated where the men are working. 5975. (Professor Dixon.) Do the men find it unpleasant P-Yes, you cannot get complete saturation where the colliers are working, but the jets are always full on, both in the intake and the return. Inside, of course, we cannot keep the jets going. 5976. How long do you work them P-In the roads where men are working we work them for two hours at a time, and 24 hours in the two main roads. 5977. (Sir William Lewis.) Have you those jets in your returns P-Yes, and the intakes. (Witness described Diagram No. 3.) 5978. (Chairman.) Now, with reference to the third diagram, is it taken in the case of frosty weather P- MINUTES OF EVIDENCE. Yes, we get a temperature of 310 at the surface, and it is much colder away from the pit top as it is surrounded by coke ovens and boilers. 5979. And this diagram represents the state of things when the sprays are on P-When the sprays are at full work with frosty weather on the surface, it is impossible / to saturate the atmosphere underground. 5980. And the general result seems to be a difference of two degrees between the two bulbs P-Yes, we do not get higher than 91 of humidity, and we cannot get it up higher. 5981. (Lord Rayleigh.) What degree of humidity do you consider desirable P-For the main roads I like to have it up to 100 degrees of humidity, but I should not have it up to that in the working place as it is not a pleasant atmosphere to work in ; and there it dries of its own accord. 5982. (Professor Dison.) Does not that keep the dust damped between 90 per cent. and 100 degrees of humidity P-It cannot wet the dust because it cannot deposit, on account of the temperature still rising. 5983. It will not deposit because where the dust is damp, it does not dry quickly P-It does not; if you can get the main roads well saturated it takes a much longer time to dry up the other roads around the faces of the workings. 5984. (Chairman.) Do you consider this system effective for this purpose P-Nearly so; but the only effective way of watering is watering by steam, that is to say, start at the pit bottom at a temperature of 850 or 900, and let the air cool as it goes round, but it is impracticable. The men cannot work, it brings down the top and lifts the bottom. I tried it once and it cost our Company several hundred pounds to repair the damage done. 5985. You do not consider that it is feasible P-No, because in practice it cannot be done. 5986. Do you consider the system of working by spray as good as any system of damping down can be P -Yes, as far as any that I have seen, as long as there is pressure to secure a good division of the water. The average is 330 lbs. to the square inch. 5987. And you do it to make it better for the men ?For the comfort of lhe men. 5988. But incidentally, under a system of this kind it does remove all danger of explosion from coal dust P -It does remove the danger, and in my opinion an explosion cannot spread along roads that are thoroughly damped. 5989. But you would not think it advisable to adopt it solely for the purpose of precaution P-I think I wouild. ,5990. Do you think that any precautions are necessary with regard to shot-firing P-None other than what are already taken. 5991. Do you use gunpowder P-No, not in dusty mines. 5992. Do you use flmeless explosives P-As nearly flameless as possible. 5993. What explosive do you use P--Gelatine. 5994. Have you tried ammonite P--No I am going to try it next week. I have tried all the others. 5995. Of those you have tried you prefer gelatine ?Yes; but it must be tamped with wet peat, and then it is practically flameless. 5996. Are there any other points which you would like to allude to P-Yes. I may mention this. I see Mr. Stokes mentioned the same roads that I have referred to in his evidence-about dust that could be taken from the pipes, and he thought there was enough dust to carry on an explosion. I do not think so myself, and since then I have had the dust analysed for moisture. The natural moisture in that coal is -80 per cent. and the moisture in the dust so found on this plane was 184 per cent., and I do not think that that would explode or ignite, the quantity is too small. 5997. (Sir.William Lewis.) You referred to the effect arising from having fine dust put into a coke oven PYea. 5998. My question is whether you said wfien the flame came out, it came out with any force in the shape of an explosion or simply a large flame P-A large ignition, 1 should say; not an explosion, just a flame. 45 5999. It came out with no force nor noise P--No, Mr. W. TVW. because it was not confined, the door being open. Hood. 6000. Have you ever tried that with the door shut P25 Mar. 1892. No, I have not. 6001. You have not tried the effect to see whether it would blow down the door P-No, I have not, it is so seldom that the thing occurs. 6002. You also mentioned to the Chairman the indications at Pen-y-Graig, the extension of the explosion being entirely due to the dust from the mine. Do you not recollect seeing indications of the effect of the explosion where there was no charred dust at all P-Yes. 6003. In the hard heading P-Yeq. 6004. And it had continued through there P-Yes. 6005. Would you suggest that it was continued through there by coal dust or by gas which had been released by the effect of the charred coal dust P-It might certainly be by gas, but I think that it was by coal dust and stone dust combined. 6006. There was no indication along the hard heading, you will admit that ?P-I admit that. 6007. None whatever P-No. 6008. But still you found the effect of the explosion beyond that, and without any indication whatever between the two points P-Yes. 6009. And you suggest that that was conveyed by the fine coal dust mixed with stone dust P-Yes, all the flame from the upper workings traversing all that distance without anything. 6010. And leaving no trace at all either in the sides or top P-No. 6011. With reference to these watering arrangements, would you consider that it is necessary that it should be conducted generally or only in collieries where a certain quality of coal is worked P-The only place I would apply it to is in collieries where the natural heat is high, in order to lower the temperature to make it more comfortable to work in. 6012. Do you think the quality of the dust has something to do with it P---Yes. 6013. Take collieries in Scotland, I know you are connected with Scotch collieries, would you consider it necessary to have watering arrangements in connexion with those collieries P--Certainly not. 6014. I was not in the room when you were explaining the whole of those diagrams, but I do not quite understand what you resort to in frosty weather where you say that you have a difficulty in getting the necessary amount of humidity P-Well, what I have done is to put a steam jet at the top of the downcast. 6015. Do you not find that that interferes very greatly with your roof and the bottom P--It is a very small jet. We couli not do it to any extent. 6016. You raise the temperature to about the normal temperature P-Not so much. 6017. The effect of that is not carried inbye P-No, only a few yards down the shaft. 6018. Then, with respect to your explosive. Are you obliged to use wet peat tamping for gelatine P-No, wet clay, or wet sone dust, but I prefer peat myself, and I use it. 6019. In every case P-In almost every case. 6020. Have you ever seen a flame with gelatine PYes. 6021. With ordinary tamping or wet peat P-What would you call ordinary tamping P 6022. Stone dust P-No. I should be satisfied if the stone dust is wet. 6023. Without being wet have you never seen a flame from gelatine with dry stone dust tamping P-Yes, I have; not a big flame, just a small flame that you could see, that is all. 6024. Have you ever witnessed a blown-out shot underground P-Yes, I have; a powder blown-out shot. 6025. To what extent did the flame continue beyond the hole in the case of the particular shot you saw PIt was difficult to say how far it came because I was in the heading that it was fired in, and not standing at right angles to the shot. 6026. It was blowing in the direction in which you were going P-From where I was standing, but I should say 5 or 6 feet only. 46 ROYAL COMMISSION ON EXPLOSIONS 6027. Was that in a place were there was fine dust ? -No. In No. 3 seam, which is damp naturally. 6028. With your experience in dealing with very 25 Mar. 1892. large quantities of steam coal in the Rhondda district, do you think it is necessary to improve any of the arrangements provided for under the present Mines Act P -I think, if the present Mines Act is carried out thoroughly, there is nothing else required. 6029. I take it you are perfectly satisfied without any further experiment with respect to the effect of coal dust P-Yes. 6030. You do not think any more are necessary P-Well, I should like to see experiments with coal dust and different kinds of explosives. 6031. What would be the object of further experiments if you are satisfied that coal dust will initiate an explosion P-I am not satisfied that it would do so with the higher explosives. 6032. That is to say, you want to ascertain to what extent the higher explosives are flameless P--Or will ignite coal dust. 6033. Because given an ignition you believe they can initiate an explosion P--Yes. 6034. (3fr. Fenwick.) I think you said that the flame of a candle would be insufficient to ignite coal dust. Mr. WV.W. Hood. FROM COAL DUST IN MINES: Would you consider that that answer would apply equally to the flame of a torch P-Coal dust will ignite at a torch, but the dust must be so thick that it would be impossible to live in such an atmosphere. 6035. The explosion that you referred to at Pen-yGraig, which you said was a dust explosion, I thinkyou said that the shot there was fired into gas; was that, so P -There was nothing definite that could be found out. But that was my own impression that the shot had been fired in a heading and that it fired gas there either in front of the shot or behind it. 6036. Which ignited the coal dust P-Which ignited the coal dust. 6037. (ProfessorDixon.) The watering which you are carrying on in your mine is done by a spray I understand P-Yes, I have got a sample spray if you would like to see one. 6038. What pressure do you work under P-335 lbs. on the square inch on an average. 6039. (Sir William Lewis.) What is the velocity of the current P-Eight and nine feet is the average velocity per second. The number of jets depends entirely upon the size of the road and the quantity of the air. The witness withdrew. Adjourned sine die. My=- At 23, Great George Street, Westminster. SIXTEENTH DAY. Friday, 8th April 1892. PRESENT: THE RIGHT HON. JOSEPH CHAMBERLAIN, M .P., CH'AIRMAN. Mr. CHARLES FENWICK, M.P. Professor HAROLD DIXON. Mr. J. WILSON, Secretary. LORD RALEIGH. Sir WILLIAx LWIS. Mr. J. McMurtrie. 8 April 1893. Mr. J. McMURTRIE called and examined. 6040. (Chairman.) You are a mining engineer, I think P-Yes. 6041. Residing at Radstock P--Yes. 6042. And past President of the South Wales Institute of Civil Engineers P-I am. 6043. What collieries have you managed P- The Radstock Collieries, the property of the late Countess Waldegrave and her trustees. 6044. For how long have you been managing those collieries P-Nearly 30 years. 6045. Will you explain to the Commission the nature of those collieries ?-They are collieries consisting of four working pits and employing nearly 900 men. They have two distinct groups of seams: the upper group called The Radstock, which 9,onsists of six workable seams, ranging from 1 foot to 2'feet 4 inches in workable thickness; the second'group, or Farrington series, t onsisting of about six seams more of approximately the same thickness, perhaps slightly thicker. 6046. For how long have those seams been working P ---The' upper group, the Radstock, has been working f6r 10' years. 6047. Is there any indication of fire-damp there in your opinion P-None whatever. During the whole of those years, as far as we have any record, and certainly within the 30 y"ears that I have known the district, t ere has 'been no solitary instance of gas ofT-any kind having been found in these mines. 6048. What is the method of working employed PExclusively the long wall system, with continuous faces of.great length, there being no hatching-off or anything of that sort, but continuous working faces, 6049. What is the character of the coal P-The coal of the Radstock series is a very hard and compact coal, and in most instances not friable. It produces house and to some extent gas coal, the small coal being used for manufacturing purposes. 6050. This coal does not give off much gas P-It gives off none whatever. 6051. You would not say that these mines were either dry or dusty mines P-I certainly would not, as far as regards the Radstock group. But there are districts here and there where the strata are very dry, and where you find,a small amount of dust. 6052. What is the character of the dustP---The dust would be for the most, part pure coal dust, but with a certain amount of shale dust mixed with it. 6053. Have you seen, in the Report made by this Commission, the Report made by Mr. We N. AtkinsonI -Ibhave. It is set out in Appendix 11 of the Report I have before me. 6054. Mr. Atkinson, Ithink, reports that in some cases which he names he found dust which might possibly be a source of danger P-Yes. I think I can quote from the particular part of his report that refers to the mines in question. I think you will find it at page 177, Appendix 11 of the First Report, and his remarks apply to No. 5 pit, near Radstock. There you will find his remarks upon the particular seams I have to do with. 6055. Will you quote the words P-He says with regard to the deeper series-the second series-that " They are the driest workings I found in the Bristol " and Somerset coalfield, and the dust in them appears " pure enough to be capable of causing an explosion if " raised and ignited." And later on he refers to the MINUTES Upper or Radstock series, where he says, " Here there " is an old engine plane about 600 yards long, in which " there is much fine coal-dust, moderately dry "(samples taken from timber and floor). If this dust "is dry enough to burn in the air, it is plentiful and "pure enough to cause a dangerous explosion." And further on he says, " From this engine plane to the " working face the road is a horse road, and the dust " very stony." 6056. During the whole time which you have known these pits are you aware of any explosion having taken place P-I have known of none whatever. 6057. Has blasting been going on all the time P--Yes, continuously. There is not so much blasting in the coal itself as in the horse roads adjoining; but these are exclusively formed by blasting, and the number of shots fired annually is very considerable. 6058. Does that apply to the particular places named in Mr. Atkinson's report P-It would, yes; and with regard to the engine plane which he specially describes as being liable to a dangerous explosion, that very engine plane has been enlarged from time to time; refuge holes have been constructed upon it, and a good deal of blasting has necessarily been done during the whole of the 29 years that it has been at work. 6059. When you blast in those places, do you take any precautions P-None whatever. 6060. You do not water the dust P-Never. 6061. And you do not remove the dust P-No. 6062. Now, speaking generally of the seams of the Radstock series, how would you describe them P-As to their being non-fiery, do you mean P 6063. As to their being dry and dusty P-I should say the seams of the Radstock series were not generally dry and dusty, but that there are occasional engine planes and horse roads which are dry and dusty, such as that visited by Mr. Atkinson, which is perhaps the most dry and dusty that we have in the collieries. 6064. Have you formed any estimate of the number of shots which are being fired P-Yes; taking the quantity of powder used as the principal guide, it appears to me that we fire about 20,000 shots annually. 6065, Does that apply to the whole district, or to the particular colliery P-That applies to the particular colliery under my management. During the 30 years I have had charge there must have been at least 600,000 shots fired in the collieries under my care. 6066. (Sir William Lewis.) Are those 20,000 shots per annum in the four pits P-Yes, in the four pits. 6067. (Chairman.) You have told us you have never kncwn of a coal-dust explosion: have you known any cases in which the flame from a blown-out shot has been extended by coal dust P-I cannot say that I have as regards the Radstock series. It is fair to assume that out of those 600,000 shots there must have been occasionally blown-out shots, but none have been brought to my notice, nor have I ever heard of a. lengthened flame, far less of an explosion, 47 OF EVIDENCE. having resulted from those shots. 6068. Does that observation hold good of the whole district P-I believe it does. I have never heard of an instance-and these things are generally known where they occur-of a blown-out shot leading even to a lengthened flame in the whole of the Radstock series. 6069. How many pits does that apply to P-Fifteen pits at present. There have been times when more have been at work. '6070. Now going to the second, or the Farrington seams, what have you to say about them P-They have been at work something like 50 years. As regards the seams themselves, they are more friable in their nature and character than the seams of the upper series, and might be called moderately dry and dusty. 6071. Have you yourself had experience of those seams P--I hve worked them for six years. Two pits out of the four that I have referred to were deepened to them some six years ago. One of those pits is 299 fathoms in depth, and the other, I believe, is 280 fathoms in'depth, and we work two of the lowest seams of that series ffrom those pits. 6072. I think it is to those seams that the quotation which you have already read from Mr. Atkinson's report as todheir being the driest workings in the Bristol and Somersetshire coalfields anplies P-That is so. 6073. (Sir William Lewis.) That is the No. 5 pit PMr J. No. 5 pit, yes. McfMurtrie. 6074. (Chairman.) Have you any experience of other districts-other coalpitsP--Yes, I have been pro- 8 April 1892. fessionally engaged in South Wales and the Forest of Dean, and occasionally in other parts of England. 6075. In comparison with those other districts, are the seams of which we are now talking, the Farrington seams, more or less dry and dusty P-I should say they were decidedly more dry and dusty than the Forest of Dean seams, but on the whole not so dry and dusty as the South Wales seams, or the steam coal seams of the Rhondda Valley. 6076. What has your experience been with regard to blasting operations in those seams P-We have carried on extensive blasting operations in them to some small extent in the coal, but to a much larger extent in the roads communicating with the shaft; the number of shots fired during the time that the seams have been opeiaed, which is only a short period, being estimatpd at about 15,000. We have fired about 15,000 shots altogether since we opened those seams. 6077. Have you ever known any explosion in connexion with those operations P-No, nothing that I should call an explosion. We have had two instances of blown-out shots that my attention has been called to. 6078. I gather from what you say that the blasting operations have chiefly taken place in the roads P-Yes, the majority of them. 6079. And then, I suppose, the dust would not be pure coal dust P-The coal dust often found lodged on timbers is really the purest of the coal dust, and where you do find coal dust in horse roads you only find it of the driest kind. But the dust on the floor would be, as you suggest, more mixed; in fact a considerable portion of it would be shale dust rather than coal dust. 6080. Have you made any experiments into the composition of the dust in your mine P--No, I have not. I believe Professor Dixon, as well as Mr. Atkinson, took samples, but whether they carried out experiments or not I am unaware. I have examined the dust in connexion with these blown-out shots I have referred to. 6081. Will you please describe the cases of blownout shots which have come under your own observation P-The first occurred at the middle pit, one of the two pits which have been deepened to the under series. This is a plan showing the two seams we work at this particular pit. The principal workings here are on the Nc. 6 or bottom seam, but the explosion occurred at Middle pit in the No. 5 seam, at a point marked A in the plan. This seam was won by a stone drift leadinoa from the shaft to where it cut the seam, and the workings are show in green on this plan, The men were engaged in forming a road and putting in an unusually heavy shot in the bottom. It was extremely hard. They put in 15 cartridges of two ounces each, making 30 ounces. I think that was the exact amount of the powder. 6082. (Sir William Lewis.) Was it compressed powder P-Compressed powder. The result was that the shot did not do its work. It heaved up the floors a little, a small rent being formed under the adjoining walls; but it blew out absolutely nothing except the ramming. It caused a very great concussion. 6083. (Chairman.) You think that the explosion was wholly due to the powder P- Wholiy dclue to bhe powder. The seam at the point in question was not dry or dusty. It had a top which gave off an amount of water, and kept the place generally damp. There was no dry coal dust. On the contrary it was rather wet. 6084. How far were the effects of this explosion or blown-out shot visible P-In this particular part of the pit the effects were felt at a distance of 300 yards away in this part here, but the effect was to blow out the lights generally throughout that part of the pit, and to open doors, and even to reverse the ventilation for a period of a few minutes. The effect, however, was not confined to that particular part of the pit, but took effect at a point 1.54 fathoms higher up in the upper group of seams-the Radstock group, where the concussion was distinctly felt, and even some doors were partially opened. 6085. And that was not in the direct line of the explosion P-Not at all. The air from the blown-out shot must have passed along this level stone drift-along the level of the road, and must have ascended the shaft, perpendicularly 154 fathoms, and then taken effect. F4 48 Mr. J. McMurtrie. ROYAL COMMISSION OON EXPLOSIONS 6086. (Sir William Lewis.) Was that against the current P-I believe it was. We were working with a brattice in the pit, with the 20 men limit, and the 8 April 1892. ventilation was not great. 6087. (Chairman.) How far along the levels did the force of the explosion extend after it had gone up the shaft for 154 fathoms P-I am not able to answer that question. The thing was not brought to my notice suffioiently at the time. 6088. But I understand you to say it did open doors along the level P-It did partially open them. I imagine at no considerable distance. 6089. But do you consider that it would be possible for 28 or 30 ounces of gunpowder to produce an effect at right angles to the direction of the shot and 900 feet above'the place of the explosion P-It would appear so. I simply give you the facts as the result of my investigation. The question was put to the officials and the men who fired the shot. It was a very unusual shot tpplied in a most unskilful way, and there does not appear to have been any chance of the shot having any useful effect. 6090. Does not the extraordinary extent of the effects of the explosion suggest to your mind that some other cause must have contributed P-No, it does not. 6091. You think that thegunpowder alone would be sufficient to produce that result P-Yea. 6092. (Professor Dixon.) You regard it as an air wave running along the shaft P-Yes. 6093. (Chairman.) What impresses me is not only that it went straight up the shaft, but that it went a distance of 900 feet P-The distance makes little difference in a smooth shaft. 6094. On the level on which the explosion took place it went 300 yards. 6095. (Mr. Fenwick.) Was it an up-cast or a downcast P-Jt was a down-cast. 6096. (Chairman.) The 28 ounces of powder carried the forces of explosion 300 yards on the level on which the explosion took place, 900 feet up a perpendicular shaft, and then for some unknown distance along the level on the top of that shaft P- You must bear in mind that it did not ascend the shaft at the end of the 300 yards. The distance between the shot and the shaft was not great-not more than 50 or 60 yards; so that the effect was.not felt much further off' going up the shaft than it was on the level. 6097. What strikes me is (and I put it to you for any observation you may wish to make) that if this shot had been fired at the bottom of the shaft and had then blown out, it would not have been at all surprising that it should have gone up the 900 feet or even more, but that, as a portion of the force of the explosion was erpended in carrying the effects of the explosion for 300 yards on the level, it is a remarkable thing that what remained was still sufficient to go 900 feet up the shaft, and then again at right angles along the upper level P -It may seem extraordinary, but the fact is that the two things were simultaneous. The current or blast FROMI COAL DUST IN MINES: 6104. What was the condition of the dust in this pit at the time of the blown-out shot P-At the point where the shot itself was fired, as I have already said, it was not dry or dusty. In the adjoining No. 6, or bottom seam, it was as dry and dusty as the one which Mr. W. N. Atkinson visited and described. 6105. Then, I think, there was another explosion which also came within your experience ?-There was at the Ludlow Pit, the second shaft that we' have to the same seam, and there are plans showing its position (producingplans). 6106. I think this explosion, that we are now going to deal with, took place in the seam which Mr. Atkinson had previously described as being dusty, and as one in which he thought a coal-dust explosion was possible P-That is so. Its general position is shown here at point A. on plan No. 1. This is a plan of No. 6 or bottom seam, and the long wall face begins here and extends by a solid line, without any break, all the way round to the place at which the explosion took place. A slight break then took place, caused by a fault. Then there is a continuous coal face again from that point to another fault, where it ends; and the explosion took place at that point A. Here is an enlarged plan of that particular spot, plan No. 2 (producing plan). The shot in question is marked there. The workings had just passed through a down-throw fault of 3 feet, and that particular part of the long wall face being opened out, inside the fault is represented by the curved line shown on the plan. 6107. Now what were the circumstances of that explosion; what was the loading of the shot P-There were four cartridges of two ounces each, making up eight ounces. 6108. Then perhaps you will describe the circumstances under which the explosion took place P-The men were opening out the coal in the way I have described, and they put a shot in at the point where the shot is marked. They put it in in a very unskilful way. They neither holed it under the seam nor over the seam, nor was it nicked at either end. So that it was quite a fast shot, and, although the charge was a very fair one, it practically blew out nothing. The shot was pointed in a sloping direction, as shown in the section. This wants to be turned about in the direction of the shot. The hole began in some inferior coal forming the middle part of the seam. It sloped slightly in the manner shown into the better part of the seam, and a little bit of tne lip of the under part of the hole was blown out. But the remainder of the coal remained entirely firm and solid, and it was practically a fast shot. 6109. And where were the men when the shot was fired P-After lighting their shot they retired here, and were standing here at the time it occurred. 6110. How far was that off P-20 yards. I will mark that place E. 6111. The men stood at the point marked E P-Yes. There were two men, named Reed, passed through the door, which they closed behind them, and were at the point E when the shot went off. 6112. (ProfessorDiorn.) Which way does that door open P-It opens inwards. 6113. (Chairman.) Did the shot have any effect upon the door P-They heard it slam; but, seeing they had closed it behind them, it was not the slam of the closilg of the door. It must have been merely that the concussion blew it up a little tighter against the frame, making a slight slam in so doing. But the door had been closed before. The door itself showed no sign whatever of fire, nor of any unusual force having been used. Over the door was a piece of brattice cloth from the blown-out shot came in one body to this point where it must have been divided-one portion went up the shaft and expended itself in the shaft, which was, I suppose, the line of least resistance, and another portion turned in the opposite direction. 6098. (Sir William Lewis.) That portion going with the current P-Yes. 6099. (ProfessorDixoon.,) How far was the effect of the flame vrisible P-I cannot give any evidence on that point, because my attention was not called to it at the time. I have the impression that the place was so damp that probably no effects of flame would have been shown. stuffed in to fill the space over the door frame, and that There was scarcely any timber to show it, the top was not blown out, although a very slight amount of being unusually strong and requiring no timber. force would have done that, nor was it singed, nor did 6100. (Chairman.) This was an extraordinary charge P it in any way show a trace of fire. -. Yes. 6114. What was the condition of the props after the explosion P-Some of the props showed marked evidence 6101. What would be an ordinary strong charge PA pound, I should say, would be a fairly strong charge. of fire. Those which are coloured dark red on this plan showed distinct traces of fire, and those that are Half-a-pound is a very common charge. coloured yellow showed none. The props that showed 6102. Therefore this might be said to be nearly the most traces of fire were the two immediately addouble a strong charge P-Yes; at all events it is double joining the shot, and the effect became less and less as what we use in an ordinary way. far as the red props are shown, until, at this point, it 6103. 1 think we have had evidence that an ordinary Lad almost disappeared. At this point, on the side biown-out shot does not go more than a few feet P-The towards the shot, there was a discolouration on the side flame, I should think, would not exceed perhaps 12 feet ; of the prop towards the shot, and you could notice the but the concussion weuld extend much furtber. sawn fibres charred a little at the end. MINUTES 49 OF EVIDENCE. Mr. J, seams in this way-that, in your opinion, coal dust alone will not produce an explosion; and that, although AMcMurtrie. it may increase the effects of an explosion, it will not 8 April 1892. 6116. (Chairman.) How far did the effect of the ex- do so to any dangerous extent P-That is so. plosion'extend as shown by the charring of the props ? under those circumstances 6133. Do you thin k, then, -Eight yards from the shot. that any additional precautions are necessary in such 6117. And that was the only direction in which the mines as those you have been describing ?-No, I do force of the explosion was felt P-That was so. I ex- not. The present Mines Act provides sufficiently for amined the workings in the opposite.direction, and I that if precautions are needed. As a matter of fact, I, could find ho trace whatever of fire. as the manager of the mine, and the Government 6118. Which way was the current P-The current was Inspector as the officer in charge, have neither of us ever as shown by arrows on the plan passing up the head in considered it necessary to put in force the coal dust a southerly direction. provisions of the present Act. 6119. In the direction in which the effects of the 6134. I understand that your evidence applies exexplosion seem to have been felt P-That is so. clusively to the mines which you have described and 6120. And were there any men in the same direction P over which you have had control and to similar mines ? -There were three men not far distant. One man -Yes. named Shearn was at the face of the adjoining road, 6135. Are you acquainted with the experiments and he was the only man who felt the effects of the fire. which have been made in connexion with coal dust ?HIe was slightly burnt on the neck and ear. I am, not with very great minuteness, but I have 6121. And what did the men who were there feel P?- made myself conversant in a general way with those They felt a blast of hot air, accompanied with a good experiments. deal of dust. 6136. You are aware that on several occasions an 6122. Was there any force ?-There was force suffi- explosion has been produced apparently by coal dust cient in the case of two men higher up the head, named alone in the course of those experiments P-I understood Seymour and Whittock, to roll them over. They were there was only one that could be traceable to coal dust in a stooping position at the time. But it must have alone. One of the German experiments with a peculiar kind of coal dust from a seam called the Pluto seam. been a very slight force indeed. I believe that was the only one in the whole course of 6123. Were the doors in the direction of the explosion the German experiments from which they obtained an affected P-They were opened at various places. explosion from coal dust alone. 6124. And what was the condition of the mine as 6137. Did not Mr. Hall obtain an explosion from coal regards dust at the time ?-It was dry, and as dusty as dust alone P-He did in his shafts; but I do not consider that seam usually is. The men are paid a special price Mr. Hall's experiments-valuable as they were in many for leaving the small coal under ground, so that the ways-a fair example at all of the conditions which entire coal face is dusty from end to end. A large part prevail in a coal mine. of the small coal of the seam is left down, and of course 6138. Does the same criticism apply to the German there is necessarily a good deal of fine dust mixed experiments P-The German experiments were applied with it. to an artificial horizontal colliery, and, therefore, the 6125. And that dust extends along the whole face of same objection would not apply as in the case of Mr. the coal ?P--It extends along the whole face of the coal Hall's. His experiments were carried out by riddling shown on this other plan. It was not confined to the a considerable amount of fine coal dust down a perpenmere point where the explosion occurred but-extended dicular shaft with the mouth of a cannon pointed into under pirecisely the same conditions right to the further it; and that represents a state of things that never does end. obtain in an ordinary coal mine. There was one solitary 6126. Then do I understand that you think that if experiment that Mr. Hall tried, I am told, in a short coal dust had contributed to the explosion it might horizontal colliery; but I am not aware of the circumhave been continued along the whole face of the coal P . stances of that experiment. The German experiments I understand were in an artificial gallery of considerable -I do. horizontal they and, in so far 6127. (Sir William Lewis.) You did not tell us the length, approach the as they wereof a coal mine;more but conditions length of this"face P-374 yards on the south. east side of nearly should not consider that to have pure coal dust still I the blown-out shot and 110 yards on the opposite sidescattered about continuously and artificially in the way the north-west side. these experiments were conducted would quite approxi6128. (Chairman.) Now do you think that in these mate to the conditions in an actual coal mine, with all explosions the coal dust that was present had any effect kinds of debris about in the roads and in the headings at allP-I believe it had the effect of extending the -coal dust and other substances alternating so, that I should hardly think the artificial conditions would flame. There is no doubt as to that. 6129. But only for a few yards ?-Only for a limited approximate sufficiently nearly to the actual conditions distance. I can give you the exact distance that the to be good criteria to go by. 6139. Have you considered whether it would be different effects were felt if you like to have them on your notes. The distance from where the shot was possible to make any experiments which would in your firedt Where the man Shearn was slightly burnt was opinion sufficiently approximate to the actual conditions to 80 feet. The distance from Shearn to Seymour, the to be conclusive P-I have. But there can be no better next ma, who felt the blast and dust, but sustained no test than to find some disused coal mine, or district of a coal mine, in which you would have the actual conditions injury, was 32 feet; and the further distance from themselves. If you could find such a district, and Seymour to Whittock, the next man up the head, was 12 feet, making a. total distance of 124 feet from the possibly there might be such, you would then have blown-out shot to the furthest man who took any something that you might safely go by. special notice of the occurrence. 6140. It would be necessary, would it not, to choose 6130. Now do you suppose that the force exerted by a mine where there was absolutely no gas P--That is so. this explosion might be wholly accounted for by the ,*: 6141. And in that case even it would be extremely explosion of the powder, or do you consider that the difficult, would it not, to watch the conditions of the coal dust had anything to do with it P-I think the coal experiments P-You could not watch the conditions of (lust contributed to it. It both lengthened the flame the experiments at the moment. But, by firing some and I have no doubt contributed to the force. shots so constructed as to blow out, or by firing a cannon, which was the substitute usually adopted, and 6131. To that extent then the presence of coal dust doing so by electricity, you could see the effebts afterin your opinion would add to the danger P-It would. But that danger. I should consider a very slight one, wards. because, you see, the traces of fire die out, as far as results from such Irops are concerned, at a distance of 8 yards, and the an6142. But how could you obtain any the results which experiment more conclusive than risk of burning from the lengthened flame only exin tended to 80 feet, because the men immediately beyond you have already obtained and,actual working P?-I do speaking from these not know that you could, sustained no injury. experiments, I say that, as far as these blown-out shots 6132. May I summarize, then, your evidence with that we have had to do with are concerned, they point iegard to these two blown-out shots, and also your conclusively to the fact that no dangerous explosion experience in connexion with the working of these would be developed in the conditions I have pointed out. 6115. (Sir William Lewis.) That is in the direction of the current P-Yes, in the direction of the current. E 82480. G t)ROVAL COMMISSION ONJ ;XOIONS FROM GO OUS 6143. What I would put to you is this, You told us that in the last 30 years you have fired 600,000 shots with, I suppose, the usual proportion of blown-out shots 8 April 1892. in your mine P-That is so. 6144. And that you have had no explosions P-That is so. 6145. Now if we were to experiment in that mine: if you were to hand it ever to us for experiments, and we were to produce an explosion by a blown-out shot, would you be satisfied that the conditions were the same as those of the ordinary working P-Oh, yes. If it was carried out in the actual mine I could not dispute the conditions then. 6146. But we might have to fire 600,000 .hots and get no resultP--It is possible: it is probable. The first point on my evidence is, it conclusively proves that the ordinary shot-firing at all events will not either cause a lengthened flame or an explosion in a coal mine. 6147. (Professor Dixon.) In any coal mine do you mean, or only in your own P-In a non-fiery mine. 6148. If I understood you aright you said your experience goes to prove that any amount of shot firing will not produce an explosion in a dusty mine; now is that to be understood with regard to mines which have come within your own experience, or with regard to all coal mines P-I speak more particularly with regard to my own experience and the class of dust in the mine that we have to deal with. 6149. And are you prepared to generalise from that to other mines P For instance, you said that the dust in the Rhondda Valley was much greater and more inflammable than at RadstockP--I should judge so from the acquaintance I had, but it is not sufficiently extensive perhaps to justify me in generalising very much from it. 6150. You would not be prepared then to say there was no danger from such dust as that P-I would rather not express an opinion upon that:. 6151. Then with regard to this shot in No. 6 seamLudlow's pit, you have given us the distance of 80 feet between this blown-out shot and the man, Shearn, who was burnt P-Yes. 6152. That is from the mouth of the hole to the man P-That is so. 6153. That probably was not the path by which the flame travelled P-No. 6154. The flame would probably have travelled a longer distance than that P-Yes, slightly longer. It could not have gone a very great distance; I should think not exceeding 30 yards. 6155. Would you call that long wall face in the No. 6 seam that we are speaking of " dry and dusty " within the meaning of the Act P-I think not; because I have not put in force the Mines Act regulation that would apply to a dry and dusty mine. But it is as dry and dusty as you usually find them in that part. 5156. You are, I presume, familiar with several of the Lancashire pits P-Yes, I have been down several of them. 6157. Would you call it as dusty as the average Lancashire pit P-I do not think I would. 6158. Do you know the Malago pit P-I do not know it personally. 6159. (Sir William Lewis.) What indications of force were there immediately opposite where the shot blew out P-I should say none whatever. 6160. No props knocked out P-Not a single prop. 6161. So that so far as you could see afterwards it was an indication of flame and hot air, and not an indication of force ?-That is so. The only evidence we appear to have of force was the fact that the two nien further on than the man who was burnt were rolled over from the stooping position in which they were engaged in their work, and a very small amount of force would have done that. 6162. Did the men at E feel any draught inwards to the face in consequence of the concussion of the blownout shot P-No; they reported none. 6163. The door that is marked D in Reed's road would, by the concussion, have been opened inwards towards the face, and not blown towards the men at E P -The direct force I should have expected would have come on the back of that door, and blown it towards Mr.4J. McMurtie. DUST IN MINEfd where the Reeds were, causing that slamming which they speak of. But I should have expected that there would have been a return current which followed it, but there was none reported. 6164. They did not feel any return current -- They did not report any. 6165. What was the quantity of air passing along this face at this particular time as far as you can ascertain P-It was a place of small area-the seam being thin, and the quantity was about 3,000 feet per minute. 6 66. And the place a very confined one P-Yes. The air was travelling at the rate of 200 feet per minute. 6167. Was there -any indication along this face opposite, where the shot blew out, of the small coal haviilg been fired and deposited on the face P-I could detect none. There were on one or two of the posts tiny globules of coke as some thought, but they were not very decided; they were not very distinct. Mr. Martin, the Government Inspector of Mines, examined the place with me, and he has had an extensive experience in examining similar conditions after explosions, and he thought he detected these minute globules of coke and dust, but was by no means decided on the point. 6168. Is it possible that the explosion, to the extent that it was, was brought about by the existence of gas there P-Well, in the first place, I take exception to the word "explosion." I think it did not amount to an explosion at all. I cannot consider it anything beyond a lengthened flame. And in reply to the other part of your question, it is not possible that there was gas there, in my opinion. Because we have worked those seams for six years under all kinds of conditions, in the first instance, leaving the shaft bottom, with only piped air; in the second instance, with very moderate ventilation from brattice, and if there had been the slightest amount of gas produced at any part of this seam we must have detected it in the course of the six years working. The only kind of gas that we have found coming from the strata has been the carbonic acid gas, which in one instance came out of the rock in considerable quantities. 6169. Then, you have never heard any report of gas from the examinations of any of your firemen, nor have any of your colliers ever seen gas in the whole of your operations, some of them being in advance of the air, during the last six years P-None whatever, nor, as regards the other series within the whole 30 years. 6170. Has there been gas seen at other collieries working this second series P-I believe not. I have no personal knowledge of any. 6171. So that you would describe this as an inflamma. tion P-An inflammation. The distinction between a lengthened flame and an explosion is, perhaps, difficult to define. But to amount to an explosion I should ex. pect to find a much greater display of force than there was in this instance. 6172. Have the men described it as a great noise like an explosion P-No; if you were to go to the pit and ask where " the explosion " occurred they would wonder to what you were referring. They were quite unconscious of anything in the nature of an explosion having taken place. The most they said with regard to it was that the noise was the noise of an ordinary shot, only a little louder-a little more shake to it, and a little more noise, but nothing beyond. 6173. What was the tamping P-Clay. 6174. And do you take any particular precautions with respect to tamping where you have shots fired in the neighbourhood of dry and dusty places P-We do not; but, as a matter of fact, either common clay brought from the surface, or soft shale which may be found in the locality, is commonly used. I should say the result of some of these German experiments rather point to the fact that there ought to be prohibition of the use of coal dust of any kind for tamping. 6175. Then, as regards the number of shots that you have fired incoal and stone during the last six years, could you give me any idea of the proportion you have fired in coal P-No, I could not; but it would be a very small proportion. 6176. It would be principally in stone P--Principally in stone. Shooting in coal is practically confined to fast ends and places like these inside faults. The coal works fairly easily in the ordinary long wall face, and the powder is neither needed nor permitted. MINUTES 51 OF EVIDENCA. " 6177. So, if I understand you aright, what you suggest is, that the flame produced by the shot in blowing out came in contact with dust, and that was carried along by the air along the face P-That is so. The fact that the flame was in quite an opposite direction from the shot itself would point to the fact that the fire fr-:m the blown out shot, catching the fine and imipa'pable dust in the air, carried it off in the direction of the current. My view of the subject is very much what Mr. William Morgans stated in his previous evidence, that where the flame from a blown out shot is in immediate contact with the dust, it will no doubt cause combustion, and that may extend to other coal dust, and so it may be extended along the face. But the effect, judging from this particular example, rapidly decreases, and, at the end of 30 yards, practically it dies out altogether. 6178. Then I take it this was a most unexpected occurrence under the circumstances existing in this face at that time P-Entirely. 6179. But, that having taken place, do you think it is now necessary that any special precautions should, be taken in firing shots in a dry and dusty place PI have not considered it necessary to take any unusual precautions since this happened, nor has the Government Inspector asked me to take any. 6180. Do you find it necessary at all, either in the first or second series, to water any portions of your workings P--No. 6181. Either by water trams or jets P-No, not for the purpose of safety. We occasionally water them for the benefit of horses. 6182. (Mr. Fenwick.) At the ploint where this blown out shot took place, can you state the distance from the fault where the shot was located P-Not more, T think, than 3 feet. 6183. Have you worked coal extensively through this fault P-We had not then. We have extended a considerable distance inside the fault since. That was the first opening beyond that fault. 6184. Would you consider that there was more or less danger of gas being given off at a fault than in the ordinary course of the seam in working the seam P-As Mr. J. an abstract question there would be greater danger of McMurtrie. gas coming off at a fault than where the seam was unbroken by a fault; but, as a matter of fact, although 8 April 1892. we have had faults at various parts of this district, we have had no gas given off from them whatever, except in the instances I spoke of just now, where carbonic acid gas was given out in considerable quantities, in fact it amounted to a blower. 6185. Have you gone through a fault of similar dimensions in any part of the seam to this P-Some as large and some much larger. 6186. And still, though you have had this exceptional case, I understand that you do not consider it is even necessary yet to put in force the provisions of the Mines Act against it P-No. 6187. In the middle pit did the force of the disturbance or inflammation, or whatever it may be termed, cross the shaft P-No, it did not cross the shaft. It went up to the shaft. The shot was on the same side as the shaft; the back of the shaft was walled, so that the concussion passing from the point of the shot out to the shaft struck against, I suppose, the walling at the back of the shaft and ascended perpendicularly. 6188. And would you not consider that the force would be somewhat broken in that case by striking against the back of the shaft P-No doubt it would be so. 6189. And even under those circumstances, do you not think that it was somewhat exceptional that, having thus struck the back of the shaft and broken its force, it should have ascended for such a distance up the shaft, and its effects even should be felt in the roadway of the seam above P-Yes ; it did seem extraordinary, but I cannot alter the facts as they are reported, nor can I account for them in any other way than I have explained. 6190. (Sir William Lewis.) What would be the average sectional area in the direction in which that travelled P-About 12 feet. I am alluding now not to the middle pit, but to the Ludlow Pit, the one in which the man was burnt. The witness withdrew. Mr. JOuN JAMEs THOMAs called and examined. 6191. (Chairman.) You are the manager of the Standard Colliery in the Rhondda Valley, are you not P -Yes. 6192. And do you come here also as representing the Colliery Offcials' Association of the Aberdare and Rhondda Valleys P-Yes. 6193. These valleys, I think, include the largest and driest mines in South Wales i-Yes. 6194. Are they fiery mines P-Yes. 6195. You have had large experience with them PYes, I have had 28 years. 6196. How long have you been manager ?-Fourteen years. 6197. Are you acquainted with the collieries in the district besides the one that you maiage P-Yes. 6198. Has your attention been specially called to the influence of coal dust in explosions P-Yes, specially. 6199. Do you consider, as the result of your experience, that the existence of coal dust is a danger in a mine P-Yes. 6200. In what way P-In carrying on explosions. 6201. In carrying on explosions initiated from some other cause P-Yes. 6202. And do you think it can carry on an explosion for considerable distances P-Yes. Q203. Does it, in your' opinion, add to the force of an explosion P-It nia--the coal dust under ordinary conditions that would be about the tips, on the roads underground, in the faces, and in confined places. 6204. What have you to say about coal dust about the tips P-I have seen clouds of coal dust about the tips thick enough for an explos'on from a naked light, if it were possible to make an explosion of the coal dust alone, and I have never seen anything of the kind. I have seen clouds of coal dust so thick that we could not see ourselves, but no explosion from it, although fires and large comet-lamps were in the middle of the dust clouds. 6205. Your conclusion from that is that coal dust alone will not explode with a naked light P-Yes. 6"206. Then, has your attention been called to an explosion which took place in a hopper under those conditions P-Yes. I say it was an explosion from gas. 6207. How could there be gas in a hopper P-I think I shall be able to explain it under another head. 6208. I think we will take it now P-Fresh dust in confined places will give off gas, which will explode from a naked light, but the coal dust proper will not. We have found that from experience. Even coal dust under water gives off a little gas. 6209. Therefore your belief is that in the case to which our attention has been called, the explosion took place from the presence of gas given off from the coal dust P-From the coal dust. A quantity of coal dust that would require six men to handle about would give sufficient gas in the upper part of the hopper to be explosive. 6210. Then, coming to your second head, have you anything to say about the dust in the workings of the mine P-Yes. In roads I have seen dust so thick that it was nearly suffocating. We could hardly breathe in it. 6211. Do you think in that condition it is dangerous P -No, not from a naked light, because we have had naked lights in those cases. 6212. And in the faces have you observed the same thing P-Yes. In the faces again, from falls of coal or roof, clouds will rise to the same extent as on the roads. 6213. Then what I understand you to say is, that in what you call ordinary conditions, coal-dust will mot explode P-Will not explode from a naked light. G2 Mr. J. J. Thomas ROTAL COMMISSION Mr. ON EXPLOSIONS 6214. That is what you call an ordinary condition P- J. J. Thomas. Yes. SAprl 1892. 6215. What do you say, where coal dust exists in the qquantities which you have described, as to the effect of a blown-out shot upon the coal dust P--The effect would be, provided that the flame be of a long duratior.. and the heat sufficient, that it would ignite the dust first, and the heat from that ignition would exude gas out of the dust, and then there might be a combination of inflammation and explosion. 6216. Therefore, dust which would not be dangerous with an ordinary naked light might be very dangerous in the presence of a blown-out shot P-Of a blown-out shot from gunpowder or from a low explosive. 6217. And the same thing, I suppose, would apply to dust in the presence of an explosion from fire damp PYes. 6218. That is to say, if there were an explosion from fire-damp taking place where there was a considerable quantity of dust, the explosion might be continued, and extended, and increased P-Yes, increased in some cases. 6219. Then what have you to say as to the effect of falls of the roof P-That would be just the same as I have said-it would cause large clouds of dust to rise. P'hose clouds of dust would not ignite from a naked light. 6220. Unless there was an explosion at the same time from some other source P-Yes. 6221. Have you observed any special effects of coal dust in connexion with safety lamps P-Yes. I never saw coal dust exploding in a lamp; it burns and inflames, but does not explode. There is a distinct difference between fire damp and coal dust ina safety lamp. The one explodes, the other only flickers and sparkles. That is my observation with the lamp. 6222. And what do you conclude from that P-That coal dust will not explode. There is great heat inside the safety-lamp, but the dust will not explode inside the lamp. 6223. It confirms your other observations that it will not explode by itself or with a naked light P-Not with a naked light. 6224. If the coal dust is mixed with fire damp, what difference does that make P-It makes very little difference inside the lamp. I have seen it in air-currents, where there would be sufficient gas to lengthen the flame of the lamp; and yet when a cloud of dust was raised, there would not be any perceptible difference in the length of the flame, only that the dust would flicker and burn. 6225. Do you think that coal dust mixed with fire damp is more explosive than coal dust alone P-Yes; it is more explosive, because the fire damp present goes part of the way to meet the gas that is given off from the dust, and then there would be less fire damp required to be given off from the dust to make it explosive if there were a little there present. 6226. Have you made any experiments in igniting coal dust P-Yes. 6227. With other materials thana naked light P-Yes, I made them with explosives. 6228. What was the result of those experiments PThat gunpowder or low explosives will ignite the dust, that is by firing some of the explosives in a heap of dust. 6229. And would the inflammation of the coal dust set up in that way be likely to extend far P-Yes, in a confined place in a colliery. 6230. Have you tried any of the patented flameless explosives P-Yes, most of them. 6231. And what has been the result P-That they will not ignite dust-I mean dust pure and simple. 6232. Will they not ignite it in any case P-No, not in any case. 6233. Does that apply to all the explosives you have tried P-To most of the high explosives. Those that I had on a special trial were ammonite, bellite, and Ardeer powder. 6234. Did you find that all these failed to ignite PThey failed to ignite the dust, each of them giving a little flash, but some lesp than others. FROM COAL DUST IN MINES: 6235. You think that the flash which is given off from these explosives is not continuous enough or strong enbugh to ignite the coal dust P-Tt is not of sufficient duration. 6236. Therefore the danger from blown-out shots in coal dust would be materially reduced by the use of these explosives ?-Yes. 6237. 1 think you have told us then that your conclusion from your experience is that although coal dust cannot initiate an explosion, an explosion may be initiated by a blown-out shot or a fire-damp explosion P -Yes. 6238. And then may be carried on by the coal dust P -Yes. 6239. And you have told us that one precaution against this danger is the use of flameless explosives P -Yes. 6240. Do you consider it necessary to take any other precaution P-I would suggest that the tamping of the high explosives should be with a damp material, and not with anything but a non-combustible material. 6241. And besides that, are there any other precautions, such as watering for instance P-Yes, would water around, according to the provisions of the Act. I have made a short summary on that point. The dangers from the presence of coal dust are secondary dangers arising from, first, gas explosions; and, second, from shot explosions. As a protection against gas explosions, the provisions of the Mines Regulation Act General Rules 1, 7, 8, 9, 10, 11, and part of General Rule 12 are sufficient, and I do not think can be improved. As protection against shot explosions, inasmuch as the dangers of shot explosions arise, firstly, from the use of a certain class of explosives, the gunpowder class, and secondly, from a certain condition of the coal dust (dryness), these dangers can be removed by abolishing the use of the gunpowder class of explosives and modifying the condition of the dust by watering as required by General Rule 12. 6242. What precaution do you adopt in the mine of which you are manager P-I adopt that. 6243. Have you any particular system of waterihg P -Yes, we have the pipe system. 6244. The spray ?-The spray. 6245. Do you use compressed air P-No. 6246. Merely the pressure on the water P-Yes. 6247. And you get a sufficient spray in that way PYes, under sufficient pressure, which we can easily get at the deep collieries. 6248. Do you get in that way perfect saturation of the air P-Yes. 6249. You have taken hygrometric observations PYes, which correspond exactly with what Mr. Hood put in his evidence. I looked over his plan and evidence, and did not think it necessary to repeat it. 6250. Yours is practically the same system as his, except that you do not find it necessary to use compressed air P-Yes, that is my system. 6251. Since you have used this system have you had any explosions P-No. 6252. Is there anything else you wish particularly to call the attention of the Commission to P-I should like to mention one thing which corroborates what Professor Abel brought before the Commission, although I did it before I saw the notes of the first edition. Additional protection from the dangers of coal dust can be secured by the use of high explosives, but it is difficult at present to say which of the high explosives is the best. From personal experience I have found Ardeer powder to give the least flash-corroborating Professor Abel's evidence, 2474, in which he refers to explosives consisting very largely of sulphate of magnesia. Now the composition of Ardeer powder is 50 per cent. sulphate of magnesia and 50 per cent. No. 2 dynamite. So that corroborates what Mr. Abel says in answer to the question 2474. 6253. (Mr. Fenwick.) I think you are of opinion that there must have been gas present in the hopper or the explosion would not have taken place simply from the dust alone P-That is my opinion. 6254. Are you aware that the windows and the roof on the top of the hopper were not sufficiently tightened down to prevent any escape of gas that may have been MINUTES present in the hopper P-They may not be close enough to let off the little gas that would be given off from the coal dust when it was undisturbed. But with six men handling coal dust as they would do, it would give off a considerable amount of gas. which would, in coming in contact with the naked lights, start the explosion. That is my opinion. 6255. Then from your experience with regard to the clouds of coal dust that are present on the pit bank about the tips, where you have big fires and torches burning, that no explosion has occurred, that confirms your opinion that coal dust alone will not create an explosion P-Yes. 6256. But would not the conditions around the tips be totally different from the conditions that obtained in the galleries of a mine P-Yes, but I have made the same observations there, and with the same result. 6257. Have you tried to set up an explosion of dust in a mine P-I have not tried to set up an explosion, but I have been under such conditions when I could not help it-with naked lights. 6258. And with a large cloud of coal dust P-Yes, too thick to see. You could hardly see the flame. It was so thick that the flame would be a dim red light. 6259. Was it pure coal dust or mixed with stone of the roadways P-In most cases it would be pure, especially in the face. 6260. It was in the face'?-It was in the face in some cases. 6261. And you had a naked light P-Yes. 6262. An open candle, or a torch-light P-An open candle. 6263. Not with a torch-light ?-Not with a torch-light in the face. But I have seen torch-lights under similar conditions at the pit bottom-in the roadways. 6264. And did the dust sparkle on the candle ?-A little around the flame. It did burn-but only what came into the flame did. 6265, But with a larger light-such as that of a torchlight which was used in the hopper P-It would not ignite unless there was gas present. 6266. You still think it would not explode ?-Yes, I am quite clear on that point. 6267. (Sir William Lewis.) I understand that you come here representing the Colliery Officials Association;-can you tell me what output you represent P-Eight million tons annually. 6268. You do not know the number of collieries PForty-five collieries. 6269. Are we to regard the views you have expressed as being the views of the whole of your colleagues or simply your own P--Partly my own and partly theirs. Most of them do not believe that it is possible to fire coal-dust pure and simple. 6270. But some of them do P-I do not know. 6271. Is there anyone who would say that dust alone would explode F-I do not think so. If you put it in that way, if you asked them ift' it was possible for dust alone to ignite I do not think any of them would say that it would from an open light or even a torch; but from the explosion of an explosive it may. 6272. A blown-out shot P-Yes. 6273. You are all in accord that a blown-out shot could initiate an explosion ?-Yes, under certain conditions. 6274. Through dust in the immediate neighbourhood of the blown-out shot P-Yes. 6275. And without any gas P-Without any gas to commence. 6276. Did I understand you aright that you believe that dust is always giving off gas, or is it simply from dust arising from fresh wrought coal P--I think that dust always gives off a little gas; but it gives off more when it is fresh. -- ---- 53 OF EVIDENCE. 6277. You spoke of flameless explosives P-Yes. 6278. From your experience, are you able to mention a single explosive that you have used that has never produced a flame in any of your shots P--I have not known them without any flame; but I have known them without a perceptible flash even in the darkness of the mine. 6279. Have you had a blown-out shot with any of these flameless explosives P-I cannot say that we have. 6280. So that really you have not tested them under the same conditions as a blown-out shot with g-n powder P-Not exactly. 6281. Is the comparison, therefore, conclusive in the way you put it, unless you have had a blown-out shot with one or more of these so-called flameless explosives. Surely you could hardly compare what the conditions would be as against gunpowder P-I see what you mean. I think I must correct myself. We have seen some of the high explosives exuloding in a manner that would be equal to a blown-out shot-that is exploding part of the charge-then it would blow out. 6282. Then would you consider it safe to use even what you describe as flameless explosives in the midst of dust in our steam coal measures, without taking the precautions provided for in the Act of Parliament for watering P-No, I would not do that, although I do not think that these high explosives would fire the dust. But still I would not do it without watering. 6283. You have said that you do not believe that there is an entire absence of flame P-Yes. 6284. But it is, you say, scarcely perceptible; therefore it follows that they would not be quite so dangerous, in your opinion, as a blown-out shot from powder P-Yes. 6285. Still, from your experience of watering arrange. ments and the precautions that you adopt in compliance with the Act of Parliament, you do not tell the Commission that any further precautions are necessary in the working of the collieries in the Aberdare and Rhondda Valley as regards dust P-Yes, that is what I say. 6286. You speak not only as a manager, but also as having been a collier yourself for years P-Yes. 6287. What would you regard as sufficient to convince you as to the possibility of dust itself initiating an explosion P-It would be tvo try the hopper under the same conditions with a safety-lamp instead of a torch. I think there would be gas found at the top. 6288. Would that convince you P-Yes. 6289. You would not require experiments to be carried out in, say, a gallery formed on the surface with pretty nearly the whole of the conditions that exist in a mine P-I am quite satisfied myself with what I have seen. 6290. You say that powder may initiate an explosion with a blown-out shot in the midst of dust P-Yes. 6291. But an ordinary flame could not possibly in your opinion initiate an explosion P--Not from dust alone. 6292. (Lord Rayleigh.) Do you think further experiments are desirable in the comparison of different explosives with one another P-Yes; I think that would give us more satisfaction generally on that point. 6293. Your own opinion is in favour of the claims put forward on behalf of the high explosives as being less dangerous P-Yes. 6294. But are mining authorities generally in agreement with you on that point P--I think most of us in South Wales are agreed on that point. 6295. But you think it might be well to arrive at greater certainty by special experiments conducted by competent authority P-Yes. -----. -* W G3 Mr. J. J. Thunmas. 8 April 1892. ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES' At 23, Great George Street, Westminster, S.W. SEVENTEENTH DAY. Friday, 16th March 1894. PRESENT : THE RGHT HON. JOSEPH CHAMBERLAIN, M.P., CHAIRMAN. LORD RAYLEIG II. Mr. T. Y. Garthwaite. 16 Mar. 1894 Mr. Sir WILLIAM LEWIs. Professor HAROLD DixoN. Mr. J. WILSON, Secretary. CHARLES FENWICK, M.P. Mr. THoMAs YOUNG GARTHWAITE called and examined. 6296. (Chairman.) I think you are general manager of the Camerton Colliery, and that you hold a First Class certificate P-Yes. 6297. Have you had experience elsewhere P-Yes; I have had experience in Durham and Northumberland as pupil to a mining engineer, and some little experience in Yorkshire, and also in Gloucestershire and Somerset, as a manager, and advising in the management of collieries. 6298. Can you give us some information as to the particular colliery with which we are going to deal to-day, namely, the Camerton Colliery P-Yes. The Camerton Colliery is situated about three miles from Radstock, and about seven miles from Bath. 6299. What are the seams workedP -The seams worked are the upper series of the iUpper division of the Somersetshire coalfield. 6300. (Sir William Lewis.) Do you happen to have a vertical section of the pit, so that the Chairman might see it P-I have not a vertical section of the pit with me. 6301. (Chairman.) At what depth is the seam worked P-The pit is 314 yards deep, and in that pit five workable seams are proved: the great vein, the top little vein, the middle vein, the sliving vein, and the under little vein. I have taken them in descending order, the great vein being the upper vein. 6302. In which seam did the explosion about which you are going to give evidence take place P-In the great vein at the new pit of the Camerton Colliery. 6303. For how long has this pit been worked P--The pits have been at work for upwards of 100 years. 6304. How long has this particular seam been worked P--The whole,of the time-the greater part of the working would be in this particular seam; the largest quantity of this seam would be worked. 6305. Have there been any explosions in the pit before P-No, there is no record of an explosion of any kind, or of the ignition of either dust or gas, that I have ever heard of. 6306. Has the presence of gas been manifest at any time P-No, it has never been reported or recorded. 6307. Did you use safety lamps in the pit P-No; I think it is probble that a safety lamp was never in the pit until after this explosion took place. 6308. You have never thought it necessary, nor has it been thought necessary to the best of your knowledge to use any precautions against gas in this pit ?PThat is so; no precautions have been taken. 6309. And you have been exem pted. I think, from the clause of the general rule, whiol applies to gassy pits ? -Yes, from so much of it as rel !testo the carrying of gunpowder into the mine in cartridges, that is :Clause B. of General Rule 12. We are allowed to take loose powder into the mine. That exemption was granted, I think, on account of the safety of the pits, and their freedom from gas. At least, that was the ground on which we asked for it; but I could not say whether that was the ground on which it was granted. 6310. How do you carry out blasting in the pt P-It is crried out with loose powder, The men charge the hole in the ordinary way with loose powder, stem it, and fire it with a straw filled with powder, or sometimes with a squib, occasionally with a fuse. 6311. I suppose gunpowder has been used for a long period P-Gunpowder has been used ever since the pits have been worked. 6312. Is the powder used for the purpose of getting the coal P--Very rarely. It would be a very uncommon circumstance for a shot to be fired in the coal. Such may have been occasionally the case, but very seldom. 6313. It is used in the rock, is it P-It is used principally for making the roadways. The seams are very thin, and the top is blasted down to make a sufficient height for the trams to pass along to the face of the workings. 6314. Do you know at all how many shots you would fire in the pit in the course of a year P--On an average about 50 lbs. of powder is used per week, which would represent somewhere about 100 shots per week. 6315. Is there any change in the way in which the powder is now used as compared with the way in which it was used formerly P-Yes, there is a change in this way, that larger holes are bored now for the powder. Formerly they used a drill which bored about an inch hole ; now the holes are about an inch and seven-eighths. Sometimes they use the smaller drills, but mostly the larger ones. 6316. And the object is to take a larger charge PYes, to do more work. The reason of it is that now they use machine drills, which they work with a ratchet brace, but formerly they used hand-drills. With the machine drill they get a larger hole. 6317. How long has the new practice prevailed P-It has gradually grown up within the last five years. 6318. Is the pit a dusty pit P-We do not consider it a dusty pit. Compared with pits that I have known in other districts, I should certainly say it was not a dusty pit. I have in my mind more particularly the Durham pits that I have seen. In those pits the trams and horses passing and the journeying of the coal raises a considerable dust along the roadways. In our pits we do not find the dust disturbed by the passage of the men or of the horses, or in the inclines by the passage of the coal along. 6319. Is the dust which is there pure coal dust or is it mixed with other material P-It is considerably mixed with shale', and that would be more so the nearet you get to the working faces; as you get further away from the working faces the coal dust would be purer. 6320. Now coming to the recent explosion, when did it take place P-About midnight on the 13th November 1893. 6321. Would you give the Commission the details of the explosion P-In the particular district where the explosion occurred there were only two persons at work, a man and a boy. They were sent there to rip down some of the roof of the incline. Owing to the upheaval of the floor the roadway had become small, in fact too small for the loaded trams to pass at that point, They were grinding against the top, and some MINU I'P OF EVIDENCIe of the coal in that process of, grinding was deposited as dust, which caused the road to be dusty at that point. 6322. At the time of the explosion then the district was in a dusty condition P-At that particular spot where they fired the shot the roadway was dusty. 6323. In the course of their work had they to fire shots P-That was their instructions, to fire in order to rip some of the top to make more height. They actually had fired one shot previous to the explosiona shot where the hole was 21 inches long. 6324. Were those two persons killed by the explosion P -Yes. When we found them they were considerably burnt, and no doubt it was from the firing of the shot. There was evidence that they had fired a shot immediately before. 6325. What' I want to know is were they killed on the spot, or were they able to give any evidence as to what took place P-They were dead when we found them. 6326. Nobody therefore is able to give evidence as to what actually took place P-No, there is no one who can do that. 6327. What do you consider took place P-- Our reasons for thinking that they had fired a shot were that we found a prop immediately in front of this hole that they had bored, against which they had evidently rested the machine in boring; we found the boring tools placed in a refuge hole close by; we found a certain amount of debris blown down by the shot; and we found their candlesticks in a refuge hole where they had evidently been sitting out of the way while the shot went off. 6328. Are you referring now to the first shot ?-I am referring to the fatal shot, if I may call it so, the shot that caused the accident. 6329. Do you know whether before the fatal shct any other shots were fired P-Yes, they did fire one. 6330. They did fire one before P-Yes. 6331. Have you any idea as to how long before P-They would get to their work about 9. and the shot which caused the explosion was fired about 12, so probably they fired the other about from one to two hours before that. 6332. They would not fire two shots one immediately after the other P-No, they did not do that, because they had cleared the rubbish away that they had got from the first shot, so that an interval must have taken place between the two sufficient to do that. 6333. Therefore the first shot could not have had any influence on the explosion P-No, the first shot had none whatever, further than that it may have disturbed the dust in the neighbourhood and made more dust in the air. 6334. Would that dust have remained in the air for two hours P-They had to remove the stuff some few yards down the incline and this they did in a " putt" as we call it locally-a sort of box or sledge; it would raise some dust in dragging this on the floor, and pro- bably the second shot would follow close upon the completion of this work. 6335. Then coming to the second shot, did you find the trace of that P-We could see the mark in the roof where it had been fired, the length of the shot and so on. I have with me a plan and a section of that shot if you would like me to produce them. 6336. Yes, if you please P-I have also with me a plan of the workings. (Producingplans and explaining them.) The plans show where both shots were fired. That upright is the upright they had the machine That upright was left placed against in boring. standing after the shot. 6337. (Lord Rayleigh.) The purchase was against that upright P-Yes ; the boring tools were found here in this manhole or refuge hole, and the candlesticks were found in that refuge hole. 6338. (Chairman.) Where were the bodies found P? The boring tools were found at 13 yards from the shot in the refuge hole, and the men's candlesticks were found at 35 yards from the shot in another refuge hole where the men had evidently been sitting at the time of' the shot. They left their candlesticks there and tried to escape, and they were fomndl at 54 yards from the shot or about 19 or 20 yards from the refuge in Which they were sitting. 56 6339. The idea is, I presume, that when the explosio Mr. 7', ;Y, took place they immediately ran out P-A.nd left their Garthwaite. candlesticks. (5340. And tried to get into safety P-Yes, I have 16 Mar. 1894. supposed that they saw some flame and fire by their leavinz their candlesticks there, or else I think they would have made some attempt to take them. This plan is a general plan and that is a detailed plan of tle shot. That is a plan of the direction of No. 2 shot. It struck the bottom of the incline at a bank of debris here-this is a bank of dust and ddbris-at a distance of 9 ft. 6 in At that point the dust was coked, and the coked dust driven into the crevices of the rock there, and this prop and this piece of wood here were thickly coated with coked dust. 6341. Was it charred thenP-The timber wat not charred, it was rather that coked dust was deposited there. 6342. Was there any mark of charring anywhere in the workings?P-There were some slight marks of charring and marks of coked dust on the timber. At this particular point where the shot struck, as I have already said, we found it, and going outwards, on the prop and chump of wood on the incline, on the corner of No. 2 refuge hole. fere is the prop and the chump of wood. At that point we found coked dust. A food bag that was hanging here was also charred; the bottom of the bag was so charred that the food dropped through on to the bottom and left the bag hanging there A plate of iron was in this No. 2 refuge hole, and that also showed signs of coke charred dust beihg deposited upon it. 6343. How far did you find traces of the explosion P -The last fall of roof is 1,261 yards from the shot going outwards. This is a plan of the workings. The shot was fired here and the bodies were found there. This is the bottom of the incline and here is the pump corner; that is Tom's road and this is the horse road. The green shows tne road on the great vein and the red shows the furthest limit of the explosion. 6344. Would you just point out what was the course of the explosion in reaching this point P-Down the incline a::d along in the great vein road. This is a cross branch to that point. That was all against the current of air I may say; that was the intake air-way; the explosion was against the current of air and in this direction; it travelled into that second door. That was the furthest point that we could trace it. 6345. Were you able to discover where the explosion was strongest P-The force of the explosion was very little on both sides of thn shot for some distance. The force seemed to become greater as it went further away from the shot. At this point, 1,180 yards from the shot outwards, the violence of the explosion was more noticeable than anywhere else. There are two doors shown on the plan at that point. These doors were blown into fragments, and the door posts and door framing were shattered as if a violent explosive had been fired right into them; in fact the iron framing of the door, It inches by half an inch, had been broken n two and bent aid contorted very much. 6346. Have you formed any conclusion as to the reason why the explosion stopped where it did -- It seemed to be owing to the dampness of the road near this point. As soon as the road became less drydamper and muddier--the explosion stopped apparently. In going inwards, in the same way, at the working faces there is more moisture, and a considerably larger proportion of shale mixed with the dust. 6347. Were there any other men in the course of the explosion P-No, there were not. There were men employed in the new branch shown on the plan, but that was a separate air current, and they did not feel the effects of the explosion in there. They felt some slight shock at the time it took place, but nothing noticeable. 6348. Have you arrived at any conelusion as to the cause of this explosion P-Yes, I have come to the conclusion that the explosion was initiated by the firing of the shot, which was overcharged, and that it was carried on by the agency of coal dust and without the presence of fire-damp or inflammable gas, beyond any that may have been evolved or distilled from the dust. 6349. You do not think there could have been any gas present from fissures or from the seam P-I see no chance of that. In the first place, for 100 years there is no record of the slightest symptoms of gas, and we G4 56 ROYAL COMMISSION ON EXPLOSIONS FROM had not cut any faults or anything in that neighbourhood that may have tended to cause a discharge of gas. In fact the workings were in their reneral normal 16 Mar. 1894. condition, and there was no reason to suppose that an) gas was coming off, nor have we found any since. 6350. Can you give me any reason why no explosion ever occurred before under similar circumstances P-I think the greater length of the roadways is one reason. The workings at that point are very much further from the pit than they have ever been before; consequently the coal had a greater distance to travel, and the waggons being open at the end causes a considerable leakage of dust. The waggons come down this incline at a great speed, which rather aggravates it; and then the grinding against the roof of the incline made more dust than 'would usually be deposited there. 6351. Has there been any change in the ventilation P -The ventilation has been increased of late years. It has been ihcreased in the last 12 months. There would be considerably more ventilation going into that particiilar district and into the pit as a whole. 6352. Do you think that has had any effect P-Yes; certainly we have found the roadways very much drier since. '6853. Has this accident led you to make any change in fhe conduct of the workings ?--Not in the working faces; we have made- no change there, but we should take more precautions in firing any shots in the roadway again. 6354. What precautions would you take P-For one thing we should be particular to carry out all the provisions of the rule as to dry and dusty mines, that is, as to watering and the removing of the dust; then we should use one of the higher explosives instead of powder, and we should take care that men well known to be competent were appointed for any shot-firing of that kind. 6355. Do you propose to give up the use of powder altogether in the mine P-We have not proposed to do so in the working places. 6356. Why is that P-The working places are damp as a rule; and not only that, but there is a considerable quantity of shale mixed with any dust that may exist there. The seams are very thin, the thickest is 2 feet, and the thinnest about a- foot, and there is a considerable quantity of shale got in making the height for the waggons to travel. 6357. What would be the objection to using high explosives in all cases ?P-The only objection that I can see is that each man in each working place makes his own roadway, and so it would be putting these high explosives into a great number of hands, some of whom perhaps might not be careful in using them, and there might be a danger in that way. 6358. Are they more dangerous to handle than gunpowder P-I suppose that some of them are not more dangerous to handle, once the men become accustomed to their use. 6359. Is there any other objection except the difficulty in handling them P-I suppose the question of cost would come in; but beyond that I do not know of any. 6360. What would be the difference of cost between a high explosive and a charge of powder such as you have been accustomed to use P-It would be somewhat higher-a high explosive would be more costly. 6361. But how much P-I suppose it would depend a great deal on what explosive you use, but I should think roughly about a third more in cost. 6362. What would be the value of that third in money; would it be a shilling for a single charge ?No, it would not amount to that. 6363. I want to know what would be the difference in cost, of a single charge, between gunpowder and an ordinary high explosive ?-We must take some particular charge to get at that. 6364. Take such a charge as you have been speaking of-a hole of one and seven-eighths of an inch ?-It would not be much on a particular shot, perhaps a fevw pence-two or three pence it may be-not more than that. .6365. In your mine there are 100 shots a week PYes, that would be somewhere about it. Mr. T. Y. Garthwaite. COAL DUST IN MINES: 6366. Therefore the extra cost of using the explosive would not be more than about 15s. a week P-That is so. 6367. Do you not think that it would be worth while to the owners of the mine to go to an extra expenditure of something like 401. a year in order to get the greater security P-Certainly, if :there is any danger in the working faces it would' be necessary to do it. 6368. But this explosion shows that there may be danger, does it not P-I am hardly prepared to admit that in the working faces; it shows it in the roadways. The conditions are different. As soon as'this explosion got anywhere near the working face it died away directly. That rather tends to show the safety there if anything. 6369. You attribute that to the fact that the working face is damp P-That the working face is damp as a rule, and that a large quantity of shale is mixed with any coal dust that may be there. -370. Why are the working faces always damp PWe find a certain amount of moisture given off generally from the roof over the coal on the great vein, and on the other seams as well. 6371. Before this explosion were you an advocate of what is called the dust theory P-No, I was not. As far. as I myself was concerned I should have allowed anyone to try any experiments in our pit. I was so confident that the dust would not explode. 6372. But you feel now, as I understand, that there is no other possible explanation of the present accident except that it was a dust explosion P--There is no question in my mind about it. I can see no chance of there being any other cause. 6373. (Sir William Lewis.) I see some faults marked upon your general plan P-Yes, that is so. I may say that we have a very large number of faults at the colliery; they are not shown on this plan because it does not show all the workings; it only shows that particular district. 6374. I was going to ask you if this shows the whole of your faults P--No ; we have, as I have said, a very large number of faults, and they are of a considerable size. 6375. Can you point out to the Commission the nearest fault P-This (pointing to the plan) is the only fault that was near there. 6376. How far was that from where the shot was fired P-About 180 or 190 yards. 6377. Under 200 yards P-Yes. 6378. 'You have shown a fault here near this staple which is stopped there; does not that extend further P -No; that fault dies out. 6379. Where you have struck faults hitherto have you found gas or water or both P-We find a little water occasionally, but never gas. I have climed high up in the drivings that have been driven in a fault many times where, if there had been any gas present, I should certainly have found it. 6380. You have never seen any gas in striking any of these troubles P-No, never. In the history of the colliery there has never been known anything to fire. 6381. If this plan correctly shows it, this place was in the goaf, and there are old workings on both sides ?PThat is so; it is cut'off in the coal on this side, and cit off by the fault on that side. 6382. What takes place after the coal has been exhausted; do you stow up the vacant place or is it left to fall P-There is no vacant place except in the roadways; the seams are so thin that not only do we fill all the vacant space but we send out one load .of rubbish to every four of coal; we have to bring that to bank in addition to filling all the vacant space. 6383. You do stow up the place where the seam has been extracted P-Wherever the seam is Worked it would be nearly close as a rule except that the roadways would be open unless they are filled--sometimes we fill them when we can get the chance to do; so, that is we fill the roadways as well as the space between. 6384. There must be some vacant space. You could not stow that as compactly as it was when the seam was there; do you think it is possible that any gas may have accumulated over a long period in any of these places P-No, I should think it was quite impossible for the simple reason that not only I myself, but hundreds MINUTES 01 of men, going back a hundred years, have been travelling through these old places with a naked light, (with a candle), and in many instances I myself have been 100 yards or more in front of the air currentif any gas were there I should have expected to have seen it, or that some one else would have done so, a some time. 6385. Did you ever test for gas P-- Not with a lamp. 6386. Did you ever test with the flame of your candle P--No, I should never have thought of it in these pits; in fact so little did we think of gas that after this explosion occurred the men that were in this new branch never dreamt that it was an explosion, although they had to come out over the falls. The only reason they could assign to me for the state of affairs was that they thought it was an earthquake. That it was an explosion never entered into their minds. I think it was the same with everyone there. As to testing for gas we should never dream of it. 6387. What does your fi reman do when he goes round in the morning before* each shift P-He goes round with a candle, a naked light, and sounds the top of all the working-places to see that the roof is secure, and sees that the ventilation is all right, and any other source of danger he would report. 6388. But he never thinks of testing for gas P-No, nothing of that. 6389. Have you any record of the number of blownout shots that you have had at the colliery over, say, the last few years P-No, we have had no record of them. 6390. Have you ever known a blown-out shot before ? -Not of my own knowledge. I have not seen one. I daresay the examiner, who is here, would be able to tell you. 6391. I think you said this was a partly blown-out shot, but that it did some work P-It was a partly blown-out shot. In most cases with these machine holes you can see some piece of the stemming in the holes; but in this case there was nothing whatever; it was evident that a mass of flame had gone down into the dust, and the debris at the side, and the very little work that it did would lead one to think it was overcharged, as a man would not put a hole in of that kind to do so little work as it did. 6392. The shot had not done its work ?-I should think about a hundred-weight of debris or stone was brought down by the shot. 6393. Have you seen shots placed under similar circumstances where there has been dust on either side before P-A number of shots have been fired in this same incline where it was dusty and nothing occurred. 6394. Equally dusty to what you assume it was at the time this shot was fired? -Yes, or nearly so. The examiner will be able to tell you more upon this point; but I think that most of them would be bored with a small drill and would not be likely to be over-charged. hole with powder. 6395. Now take the shot that was fired, I think you said to the Chairman, a couple of hours previously ?Yes, or about that time. 6396. So far as you could judge that shot had done its work ?-Yes, it did very good work. 6397. How do you account for that charge having gone off without any explosion when the dust was lying about in the same way, and this causing an explosion in two hours afterwards, the difference being such as you have indicated, that it did not do its workunless there was something else than the dust in the immediate neighbourhood of the shot ?-I would account for it in this way: In the case of the first shot the mere fact of its doing its work shows that there was very little flame coming out of the hole-in fact I could see that from the stemming which was left in the hole.. I could trace the stemming left in there, showing that the stemming was not blown out. 6398. Are you speakinig of the first shot now ?-I am speaking of the first shot; you could see the marks of the stemming left in the hole. In the second instance, you could see no mark whatever of any stemming, it was all blown clean out. In addition to that the second shot was pointed more directly down into the dust; it struck the dust at 9 ft. 6 ins. from the hole, and the first shot would strike considerably further down the incline. E 82480. EVIDENCE. 57 Mr. T. Y. 6399. Do you think that of itself would account for the difference in the effect of the two shots -I think Garthwaite. it would have a great deal to do with it, if, as I suppose, one was nearly a blown-out shot and the other 16 Mar. 1894. was not. This No. 1 shot is pointing more that way; and not only that, but it blew a large piece of ground out. No. 2 shot only blew out this little piece there. You will see it on the section better. That is the end view looking up the incline across here. It blew out a very small piece of ground there. 6400. Did it occur to you that there was any great force when this shot blew out, having regard to the fact that none of these timbers were blown out PThere was very little force to be seen for a considerable distance each side of the explosion; there is very little sign of force for 128 yards outwards from the shot; then you come to the wheel on the incline; this wheel has shifted from its position; then you get a succession of large falls extending to the bottom of the incline, 311 yards from the shot-that incline is nearly one continuous fall with the exception of a few timbers left standing. 6401. All in the direction of the fresh air ?-All against the fresh air. 6402. Were those portions from your previous knowledge of them more dusty or less dusty than where this shot was fired ?-The point in the immediate neighbourhood of the shot would be more dusty, and the incline to the bottom would be more or less dusty. On the little vein from the bottom of the incline to the bottom of the dipple, it would not be so dusty ; but with the exception of that the whole of the great vein road and the horse road would be dusty. When you come to the main branch, where the explosion ended, for a distance of 80 yards or so is more or less wet and muddy; there is moisture present both on the bottom and in the top. 6403. Were there any places along here that were wet and where the explosion continued, notwithstanding the wet places P-No; the great vein road from the dipple outwards to the pump corner would be dry throughout, and it would be more or less dusty. 6404. But not what you previously considered dry and dusty in the ordinary acceptance of the term ?I did not consider that our pits were dry and dusty in the ordinary acceptance of the term at all, as far as my experience of other pits compared with this gces it was not dry and dusty. The coal dust was not pure it was mixed with shale and heavy, it would not float away with the air-current. On being disturbed it would not float away. 6405. What is the thickness of the strata between this seam and the next seam immediately below ?From 10 to 12 fathoms, that is from 20 to 24 yards. 6406. Do you ever have any upheaval at the bottom under this seam P-Yes, the bottom is a soft black shale, and it does heave, especially where there is any imnisture in it. 6407. Are there any riders between that seam and this coal, or is it simply rock and shale P--[n most instances it is simply rock and shale. 6408. Then what is the next seam above this P-This is the top seam. 6409. What is the nearest coal here. You have some thin riders, if I remember your section aright; there is a rider, I think, above this great vein, is there not P-Not anywhere near it. 6410. How near P-Not within 30 or 40 fathoms, I think, not at our pits--at some of the pits it is so. 6411. It is so at Radstock, I know P--Yes, it is so. There is a seam at Rddstock, I think they call it the Witty Mills Seam, which does not exist at our pits; that is above the great vein. 6412. I did not know that your section was so different. When you have had falls of roof, have you ever observed any difference P--In what way P 6413. Have you never had any gas of any kind either from falls of roof or from the lifting of the bottom or out of the seam P--No. I have been on the top of falls of roof, and, as I have said, I have climbed up beside the face of faults; if there had been any gas there I would have been sure to have found it. 6414. And the only reason that I understand you can suggest for the difference which has led to this explosion was the size of the bore P-And the greater length of roadway and the open end trams. H 58 MAr. T. Y, Garthwaite. 16 Mar. 1894. *****- - ft ROYAL COMMISSION ON EXPLOSIONS FROM COAL 6415. And that it was practically a blown-out shot ? -Ahd that it was a blown-out shot. I may say that I am having our waggons made close in the end. I think the Chairman asked me what precautions should be taken. I forgot to mention that. A precaution which I should suggest and act upon is that the waggons should be made as close as possible to prevent leakage. 6416. That would be a precaution as regards quantity of dust only P-That is so, as to the quantity of dust inthe roadways. 6417. Do you use much powder in the face, in the actual getting of the coal P-No, it is very rare that a shot is fired in the coal. 6418. And you would not think it necessary. I gathered from an answer you gave to the Chairman, that the same precaution should be taken in the face where the dust is mixed with shale, as you would in the roadways where it is fine dust P-No, I do not see that the same precautions are necessary there. 6419. In one of your answers you indicated that in your opinion this was due to want of experience on the part of the particular workmen-that the hole was badly put --Yes, it was badly placed and over-charged. There was very little work that it could do; there was a joint at the back of the hole which prevented it from spreading further. 6420. Were they men who had had considerable experience in the mine, or were they working in coal without having had much experience in hard ground P -The man had had a certain amount of experience in hard ground, but perhaps not so much as some-he had worked in the pit from a boy, and had had general experience of all the work. 6421. (Mr. Fenwick.) What do you understand by a dry and dusty mine P-As far as I know there is not an absolute definition of a dry and dusty mine. When I speak of our mine as not being dry and dusty, I have other mines in my mind with which I compare it, more particularly the Durham ones. 6422. Then we may take it that you are speaking comparatively P-Comparatively. 6423. And that this mine was not so dry and dusty as other mines P-That is the case. 6424. But is it not the fact that you had to load up the dust each day from the incline P-No. I think that was not done each day, it was done from time to time. Certainly, as I have said I think, in my evidence, at the point of the explosion, it was considerably drier and dustier than at any other point. 6425. At any rate if not each day at short intervals you had to fill up this dust into the trams, and send it out of the pit P-Yes, but it would not be all coal dustthe bottom is very soft at that point, and is constantly heaving up; that and the grinding from the passing of the trains would produce a black shale dust mixed with the coal. 6426. Did you ever take any precaution to water the dust before.firing the shots P-No, we have never done that, Our roadways are not dry ana dusty as a rule. At this particular point, it was more like a dry and dusty roadway than at any other point in the pit. 6427. I think I understood you to say that your fiireman examined the mine before the workmen went in with a naked light P-That is so. 6428. Do you think that that is a wise practice, or a safe practice I will put it P--Taking the pits on the upper series about Radstock, I suppose that there is hardly one of them that has at the present time a safety lamp in the pits, and some of them have been working considerably longer than we have-that is, over 100 years. There is no record of any gas having been seen or found. 6429; Do you think that the fact that there is no record of any gas having been found is a sufficient justification for examining the mine in the morning without taking the proper precaution of having a safety lamp P-Yes, that is how we look at it. 6430. Is it not possible that during the night a disturbance may have taken place which may have liberated fire-damp from the strata, of which you have not been aware P-It might be possible, but it seems very improbable, considering that, as I say, we have had a very large number of faults there. They have been ocut many times during the last 100 years, and nothing of the kind has ever been found. DUST IN MINES: 6431. What evidence have you that this was an over. charged shot P-It is perhaps a great deal assumption. We assume that the man would not put in a hole of that kind to blow down so little stuff as he did, and that he must have had an intention in his mind to do more work than the shot actually did. I have examined the hole very carefully, and as far as I can see from the blackening inside the hole, I think he had about 41 inches of powder in there. If he had that amount of powder certainly it would be an over-charged shot for the amount of work that it did. 6432W.(Sir W. Lewis.) A 1--inch hole, did you say it was P-No, 17 of an inch. 6433. (Chairman.) What was the length of the hole P -It was 10 inches in length altogether. 6434. Therefore about half of it was filled with powder P-Yes, nearly half; that is as far as I could judge from the blackening within that part of the hole that was left. 6435. (Mr. Fenwick.) But is it not possible that when a shot has not done all t"hat it was intended to do, the fact that it has not done that may be due to an undercharge as much as to an over-charge P-Yes, it might be so, but then anyone going and seeing that shot and the way it was placed, and seeing the joint at the back of the hole (which evidently prevented it from spreading) would come to the conclusion that the shot was not under-charged but over-charged. 6436. Was the strata broken off at this parting PYes. 6437. But the powder was laid beyond the parting P -No, the parting was 3 inches beyond the back of the hole. 6438. Beyond the back of the hole P-Yes. 6439. Then in that case the debris was blown down P? -Was blown from the joint or parting. 6440. Then you say the hole was beyond the joint PNo, the joint was beyond the hole. It was 3 inches beyond the back of the hole. 6441. I think you said that the increased ventilation had something to do with the explosion P-It has made an increased dryness in the roads which has been very evident-more so since our attention has been drawn to it since the explosion. We can see it more plainly than we could before. 6442. Do you consider that an increased ventilation in a mine is an additional source of danger P-I think it is as far as the coal-dust explosions are concerned. It would seem to be so. I may say that this road, when I first came to the pit was the return air-way, and there was not then so much ventilation and the road was in a very damp state and anything but dry and dusty; but since we have made it the intake and more air has gone in it is much drier and much dustier. 6443. I think you also said that the reason why you do not use high explosives in the face is because at the face you have a considerable quantity of moisture. Would you say that where such conditions do not obtain gunpowder at the face should be prohibited PDo you mean as to moisture only, because one of the reasons why I say it is safe to use gunpowder at the face is on account of the large amount of shale that is present with our seams P That would not apply perhaps in other cases. It applies to our case, but it would not apply, generally speaking. Our thickest vein of coal is only 2 feet and the thinnest is 1 foot, and averaging it over a period we send out one load of shale to four of coal, in addition to packing the vacant space as full as we can get it, so that there is a large amount of shale mixed with any coal dust that may be present at the face as well as the moisture. 6444. Do you work on the long-wall system or on the bore-and-stall system P-On the long-wall system. 6445. I understood you to say, in answer to a question of Sir William Lewis, that you packed closely between your gateways; is that so P-As I say, in most instances the stuff is more than sufficient to pack it closely; in some instances there would be a little vacant space. The men hole underneath the coal in the shale ; they do not hole in the coal, and the shale in most instances from the holing is sufficient to fill the vacant space between the pack walls. 6446. If it is not sufficient you do not import any to fill it up ?-Not as a rule. MINUTES OF EVIDENCE. 647. (Professor Dixon.) You said that the depth of the shot hole is 10 inches, and that it is within 3 inches of a fault; in your opinion had the fireman observed that fault P-It is rather difficult to say, but I should think not. 6448. If he had noticed it would he, in youl' opinion, have bored his hole in that position P-No, I do not think he would. 6449. Is such an occurrence as this, the production of a large flame in a dusty place, a very rare occurrence P-In our pits P 6450. Yes P-It is, especially with the smaller holes. 6451. I mean is a blown-out shot or a shot of this kind which did not do the work intended, and therefore which produced a large flame, a rare occurrence P -Yes, I think it would be. 6452. In your experience P-I think it would be a rare occurrence. 6453. In the falls of roof that occur would you expect to find gas in any of the cavities so formed if there was any gas in the strata P-I think my answer to that is that there was no one at the pit who at all expected to find it anywhere in our pits. I and others have been everywhere about the pit with air and without air, over falls and up faults, and we have not found any gas, so that none of us expected to find any. 6454. Speaking from your experience of other pits, after the explosion would you have expected gas to accumulate in the cavities of the roof where the falls occurred P--I could hardly say after the explosion. 6455. If there was any gas present I mean P-I am not quite clear on that point whether you would or would not. The air that was passing went over the top of the falls after the explosion, and it is possible that it might clear out any gas which was there; the current of air travelled near the roof after the explosion. 6456. Were there cavities in the roofP--There were some cavities, and I should have expected to find gas in those where they were a considerable height above the-air current if any gas had been present. 6457. There were such cavities P-Yes. 6458. You say you think the mine is rather more dusty now than it was some few years ago P-As far as this district is concerned, I certainly do think so. 6459. How long have these trams with the open ends been employed P-More or less during the whole history of the colliery. At one time I understand they used to use some loose boards to put in the end, but I do not think that that was carried on for any length of time. I mean to say that it would not be general; it would only be occasionally that they w*ere used. 6460., As long as your experience extends, have they always used those open ends P-As long as my experience extends--for the last nine years-they have been open ends; and previously. 6461. I suppose that was for the convenience of put- 59 Mr. T. Y. end to the candlesticks, and the candlesticks were stuck in the sides. The sharp-pointed end was simply pushed Garthwaite. into the loose stuff (which is frequently done) and there 16 Mar. 1894. they were found intact. 6467. The candles themselves were not bent or upset, were they P-I could not speak positively upon that point. I am not certain whether one of the candlesticks was not changed before I saw them. I took particular notice of it; but as far as I know, they were not bent. 6468. Have you marked on the plan of the pit you have brought to-day, where the moisture begins going out-bye from the pump corner P-1 o, that is not marked there, but I can give you the distances. For 156 yards outside the pump corner towards the pit there is no dampness, and dust is prevalent. Beyond this, there is water and mud in the roadway, and for some distance the top yields a little water. On this last length the disturbance ended, the whole length of this mixed wet and dry roadway being 53 yards. 6469. Does that take us up to the first fall, or is the first fall further out than that P-The first fall would be just beyond that. The last two falls are in that 53 yards of roadway. 6470. Did you notice whaJ was the greatest length of damp roadway that the flame leaped over P-That would be the greatest distance of absolutely damp roadway-that 53 yards. 6471. But there it appears to have stopped P-There it stopped. 6472. Previously to the flame reaching that point it had gone over one or two places that were damp, had it not ?-Yes, from the bottom of the incline; which is 311 yards from the shot to the dipple, which is marked on the plan distant 474 yards from the shot; that would be slightly damp I should call it-not so dry and dusty as the other. A little water was lying at the bottom of the incline 311 yards from the shot, and for 160 yards from thereout the road would be somewhat damp. 6473. I am speaking of an actual puddle or moisture lying on the floor P-There would not be anything of that kind except these 53 yards of which I am speaking in which the last two falls occurred. 6474. (Sir 1W. Lewis.) That was the termination PYes. 6475. (Professor Dixon.) It was near the termination at any rate P-Yes. 6476. There was no actual wet length to which you can refer in your memory that the flame must have leaped over except this place near the bottom of the incline P-There was nothing actually wet and muddy, except this place near the bottom of the incline. There was a little water just at the bottom of the incline. I do not know whether it was in consequence of this, but at that point there were no falls, and the timber was not knocked out. 6477. But there was some charring near that point P ting the coal in P-It is principally on that account. -- There was some charred dust nearly over some loaded It is convenient to put the large blocks of coal from the low seams in like that. I may say in connection with that, that I think of late years the men and boys in the working places have loaded up a considern bly greater quantity of small coal than they used to formerly. That is shown by the books of the colliery. They use the shovel more in the heads, but formerly hat was prohibited. 6462. Would that produce more dust P-Yes; there gould be more leakage at the open end the more small there is; if the coal is hard or block, the less leakage here would be. 6463. Mr. Martin I see speaks of the grinding of the :oal; does he refer to the grinding of the mass of the oal in the tubs, or to the coal piled up in the tubs itriking the roof P-I think he was referring to the grinding against the roof. The roadway was low at hat point. 6464. That did actually occur P-Yes. 6465. To your knowledge P-At that point; that was he reason the men were there, to make more height. Lhat would be Mr. Martin's meaning, I think-grinding 6gainst the top. 6466. Then with regard to the effects of the explodon, the candles were found, I think, standing upright, mnd not much damaged P-There was a sharp-pointed trams of coal that stood there, and part of the coal was blown out of the tram, which accounted for the charring. 6478. Your opinion then is that the coal standing in the trams would yield some dust P-Yes. 6479. And so carry on the explosion P-Yes; that is my opinion. 6480. Then with regard to this worked-out coal, can you get any distance into that old road, or could you at the time of the explosion get any distance into that old road, whioh is just before you reach the shot, going in P-Yes; a man was in there with a naked light some few hours before these men went to work, and they themselves were in there putting some of the d6bris from their first shot in there. 6481. Stowing it away there P-Stowing it away. 6482. Did they stow the d6bris of the first shot in there P--Yes. 6483. They would go in with their candles then P-Yes. 6484. So that within an hour or an hour and a half men with naked lights had been into that old road PThat is so. 6485. So that any gas there must have been detected P -Yes. H2 60 IOYAL COMMTSSION ON EXPLOSIONS 6486. (Lord Raleigh.) You told us that in all your experience of the mine you had no knowledge of any gas being found there; since the explosion have special 16 Mar. 184. tests been made as to the presence or absence of gas ?Yes. Professor Dixon has, I think, made some tests, ad Mr. Martin, and Mr. Stokes, with his lamp, haive made tests. Mr. Martin has been down two or three times, and made some special tests. He had the workings closed up for some 10 days, and after that he came and very carefully tried it with a safety lamp. Mr. T. Y. Garthwaite. 6487. Mr. Martin is the inspector? -He inspector of our district. is the FROM COAL DUST IN MINES : 6488. (Professor Dixon.) Were you with hin) when he went down P-Yes, I was with him. 6489. Would you tell us on this plan where the stoppings were put after the explosion P-A stopping was put just inside the dipple, which stopped the intake air. 6490. Robert's dipple ?-Yes, just inside the dipple. The other stopping was put in the return airway. I do not think I can give you any particular point. It was actually here, but it was put somewhere there. 6491. Would you show it me on my plan ?-Certainly. [The witness imarked the position on the plan.] The witness withdrew. Mr. J. Brown. Mr. JOuN BROWN called and examined. 6492. (Chairman.) You are an examiner and fireman in the Camerton Colliery, are you not ?-Yes, 6493. Do your duties lead you to the part of the colliery where the explosion took place ?-Yes. 6494. It is on that district that you are acting as examiner P-Yes. 6495. What time were you there before the explosion ? -About 1Q.30 in the day before-on the 13th. 6496. And the explosion took place about 12 o'clock at night P-At night. 6497. What was the condition of working at the time you were there P-All safe and the ventilation good. 6498. You do not examine for gas I understand P?No, never did there. 6499. Was there much dust there P-Yes. 6500. How much dust should you say P-I could not say exactly how much, but I know there was the incline being altered from a double run to a single run. By doing away with one run that allowed space on each side of the rail, and we had to clean up from the rails that were there and throw it at the sides until it was convenient to fill the tubs with it and take it away. 6501. Thererore there would be an amount of dust on each side P--Yes, a bank of dust on each side. It is not often that we have got room on each side of the rail to throw anything, so that there would have been more dust there than there could have been if there had been two runs. 6502. How long have you been working in this colliery P-21 years on the 13th of this month. 6503. Have you ever known any gas to exist there ?I have never seen any there. 6504. Do you think there could havt been any gas at the time of the explosion P-No, I do not believe there was. 6505. I-Iow quickly were you on the spot after the explosion P--It was not before mid-day when 1 get there. 6506. Then did you examine the shot-hole P-Yes. 6507. And you found, I understand, a joint at the back of the hole P-Yes there was. 6508. HIow much powder do you think had been put in P-As I judged myself I should think seven or eight inches. 6509. Seven or eight inches of powder ?-I should think there was. 6510. What would be the usual charge for a hole of that size, how much powder would they put in P-I could hnot say much about that one, for I should never put a hole there and I should have no judgment on the bole at al.1 If I had made a hole there I should have bdored another one and never done anything with that. 6511. That is to say you would have found the joint there P-Yes. 6512. And you would have made a hole in a different place P-Yes; if I had not seen the joint I should not have bored a hole there. It was a mistake in judgment somehow or another. 6513. Do you think the powder blew out ?-Yes, I think it did. 6514. It did bring down some rock, did it not PYes, a little. 6515. How much did it bring down - Perhaps nearly a hundredweight. 6516. Did it bring down up to the joint P-Yes, to the joint. 6517. But it did not shake the joint, or go beyond? -No, not beyond. 6518. Was the part of the mine where the explosion took place more than usually dusty P--Yes, that was. It was rather more so than we had ever seen. The reason of it was that the loads travel fast there, as the bottom half of the incline is so much steeper than the top ; then there are four loads at a time, where we do not as a rule run but two anywhere else in the pit; then there was a little more air going, so that when the load is run through at that particular point it would cast such a dust behind that you could scarcely see or come through it for a few seconds. 6519. I see that before the coroner you said that you had noticed nothing unusual in the amount of dust ?-No, that had been carrying on ever since the incline had been put into the run like it is now. 6520. How long is that P-About 18 months. 6521. T herefore, during the last 18 months there .has been always a great deal of dust there ?-Always dust there. 6522. Do you know whether there has beenl any previous blown-out shot iii that neighbourhood P-No, I have been there all through it. -We would lore some days two, and some days three holes, but they were hand-drilled ones. 6523. Do you have many blown-out shots?--In the face we do very often. 6524. And in the rock ?-Yes. 6525. You do P-In the rock and in the face. 6526. Are the faces dusty ?-No, there is a moisture and all that, and a sweating in-the top. 6527. They are always damp, are theyP--Yes, in those districts and through the pit there will remain a moisture from 20 to 30 yards back, and then after that drying will begin. 6528. When you examined the workings afterwards did you examine them with the naked candle ?-No, with a lamp. 6529. Was it a safety lamp ?P--Yes. 6530. Was that the day after, do you mean P-On the 16th I started it for gas with the locked lam p and followed on to the 24th every day. 6531. Did you find any gas -?-No, nothing. 6532. (ProfessorDixon.) Was that a Davy lamp PYes, I found some coke handy where the shot was fired. It has rough walls there, and in amongst that I found a bit of dust burnt into coke. 6533. When did you first get into the incline after the explosion P--On the 14th. I was not forward enough to be of the company that found the bodies, but I was just behind. 6534. Did you notice the men's candles in the refuge hole P-Yes, I saw one there. 6535. Was it damaged P-No. 6536. Was it standing upright ?-Yes, except; that the wick of the candle was drooping. 6537. (iMr. Fenwick.) Why should you, if you had been in charge of that job, not have placed your shot where it was P-Because it would have been against my judgment. MINUTES OF EVIDENCE. 6538. What circumstances were there that would have led you to that conclusion P-Just above there was a hollow in the roof and it could have got there. In my experience of powder in blasting I always find it to do more work down the hill; it will take better in blowing down the hill. So, if I had been there, that is how I should have advised them to put it. Then there was what I have never seen ever since I have been in the habit of usinlg powder, and I have used a good bit. They commenced the hole from nothing and bored ten inches, letting it go up ten inches. They should have begun at nothing and slanted it more. 6539. Do you mean to say that the hole rose too rapidly P-Yes, that is what I say. 6540. Nas it far from the side P-From the side of the road do you mean? 6541. Yes ?-It was put in the centre of it. 6542. When you changed the run in the incline from a double to a single line, did you put the run in the centre P-No, we put it as true as we could for the rail to be straight. At some places it would come handy for it to be on one side, and at another time it would come in the middle, and at another time on the other side. We put it on the straight, because it had to run so fast. 6543. You found some considerable inconvenience from the dust that accumulated on the incline, did you P-Yes. 6544. Do you think it would be true to say that you had to fill up fromnt one to two trams a day from the incline P-No, I should not say that-I should say four a week, as I very often do it myself. 6545. Are you aware that r[. Martin says that in his reIort P-Yes, I expect so; it was what I said myself. 6546. Then you think the report is not strictly correct, then P-I say there was not one or two a day, but I say there were four to five a week. 6547. (Sir W. Lewis.) Have you seen gas in any other colliery than this P-Yes. 6548. Where ?-At Blaina, South Wales. 6549. How long did you work there P-A year and 10 months. 6550. Was that before you were appointed fireman at this colliery P -Yes. 6551. Had you any acquaintance with testing for gas at Blaina P?-Yes. 6552. As a collier ?-Yes, as a miner. 61 6553. And you worked there with a safety-lamp PYes. 6554, So that you would know gas when you saw it P -Yes, I should know that. 6555. You said there were 7 inches or 8 inches of powder put in this hole, and that that was too much; how much would you consider sufficient for such a hole, even if you would put it there at all P-If it had done its proper work that it was intended for I should think 2 inches would have been plenty from what I could see of that. 6556. Instead of 7 or 8 inches ?-Yes. 6557. I also understood you to say that instead of putting the hole there (pointing to the plan) you would have put it here and worked this way P-Yes, that is it. 6558. Did I understand you aright to tell the Chairman that there was more dust there than was usual in your colliery in consequence of the change which you said had been made there ?-Yes, that would be through the change. Mr. J. Brown. 16 Mar. 1894. 6559. You said that there was a bank of dust on each side P-Yes. 6560. And that is unusual in the other places of the colliery ?P-In other places of the work you would never find room to do it. 6561. Have you had much experience yourself in shot firing in that colliery ?-Yes. 6562. Both on the main roads and in the face ?Yes. 6563. Have you ever seen a blown-out shot P?-Yes, I think I see them every week now. 6564. On the main roads P--In the face, not on the roads. 6565. You have never seen a blown-out shot in the main roads P-I do not know that I have noticed them on the horse roads or that. We should hardly ever fire any out there. 6566. Where you have had a blown-out shot in the face have you ever had any accident ?PNo. 6567. But there you told the Chairman that the place is damp P-Yes, it is. 6568. And that the small coal is mixed with shale P-Yes, that is true. The witness withdrew. Mr. JosEPH SAMUEL MARTIN called and examined. 6569. (Chairman.) You are one of the Inspectors of Mines, I think ?-I am. 6570. And you have had a good deal of experience of explosions P-Yes. 6571. In what districts P-In the East Lancashire or Manchester district, in the South Wales district and the South-western district. 6572. Have you given any attention to the question of coal dust as an agent in explosions P-Yes. 6573. What has been your opinion hitherto P-I have been of the opinion that it has had the effect of extending explosions, but until comparatively recently I have not been of the opinion that it was an agent which would, you might say, cause an explosion. 6574. Have you recently seen reason to change your opinion P-Yes. 6575. What has been the cause of that change P--In the first instance the explosion or rather the extension of flame from an explosion in blasting which Mr. MacMurtrie has explained to you; it occurred at the Ludlow's pit at Radstock in, I think it was, November 1891; subsequently experiments made by Mr. Hall; and then recently an explosion which occurred at the Camerton Colliery in the Radstock coalfield. 6576. Dealing first with the explosion in the Radstock Colliery, was that in your opinion an explosion entirely due to coal dust P-I have no doubt about it. Of course it was an explosion of gunpowder in the first instance. They were blasting, and the extension of the flame was due to dust, 6577. But in your opinion there was no gas on that occasion P-None. 6578. The latest of these explosions is the one at the Camerton Pit P Yes. 6579. In that case have you any doubt as to the cause of the explosion P-Not the slightest. 6580. To what do you attribute it then P-To a shot fired in the roof igniting dust, which lay on the flooi and perhaps to some extent at the sides. 6581. Are you convinced that gas played no part in tnat explosion -Fire-damp played no part whatsoever ; whether gas was distilled from the coal dust, of course I am not prepared to say. 6582. But you are of opinion that there was no gas in the workings previous to the explosion ?Certainly. 6583. What are the grounds upon which you base that opinion P-The mine itself has been worked for about a century, during which time fire-damp has been totally unrecorded and unknown. This series of seams, that is the upper series of the Radstock or upper division of the Somersetshire cialfield, has never been known to give off fire-damp in any part of the coalfield. 6584. How long was it after the explosion that you visited the pit P-About 16 or 17 hours 6585. Did you then make any examination for fire. damp P-I went with a naked light to the point where the shot was fired. About 2,100 yards from the shaft, IH3 Mr. J. S. Martin. 62 ROYrAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MIN ES: 6601. What extra precautions would you recommend to be taken to meet this danger P---In the first place I should prohibit the use of powder, which I consider is unknown at that colliery previously, and I asked the Although the high the most dangerous explosive. 16 Mar. 1894. manager if he had a safety lamp in order to go forward, explosives are not actually flameless, some of them but he had none. Then I asked him that the next morning he might have them so that we might go into ,which as nearly approach it as possible) should be made use of. the faces. I did not feel justified in going forward without safety lamps. The next morning he had safety 6602. Would you allow no exceptions to the prohilamps', having sent to a colliery about seven or eight bition P-In consequence of the possibility or likelihood miles away, the nearest at which safety lamps are kept. of its being used where it ought not to be I should be We then went into the faces of the workings and found inclined to go the full length and prohibit it. no trace whatsoever of gas. 6603. Would there be any inconvenience to the mine6587. Did your examination of the mine show how owner if he were prohibited from using powder P-I am far the explosion had extended ? - The roads were not prepared to say exactly whether the expense is damaged to a point within, I think it was, about 700 greater or not, but I believe some of the present exyards from the shaft. I have a plan here. The shaft plosives would otherwise effect the object without inconwas here and this is the road in. The outside fall, I venience. think, was about 760 yards from the shaft. -3604. The only difficulty that you foresee would be 6588. How far distant was it from the explosion P-one of cost P-Yes, and that would be very trifling, I About 1,350 yards from the seat of the explosion. should think. 6589. Was there any evidence as to where the force 6605. Have you had any experience of watering mines of the explosion was greatest P-From about 200 yards from the seat of the explosion right away to the pump where considerable quantities of dust prevail P-Yes. corner. 6606. Do you think that is a necessary precaution P6590. (Sir William Lewis.) Right back P-Right Yes, I think it is a highly desirable and necessary precaution, but I do not think that it is totally effective. back. I do not think that a mine can be so thoroughly 6591. (Chairman.) To the pump corner P-Yes) watered as to render it safe by watering alone. which would be a distance (cfa thousand yards. 6607. In the case of a mine where fire-damp exists, 6592. Was there anything to account for the failure and where an explosion of fire-damp may be initiated of the explosion from that point P-There was a certain either by one of the high explosives or in some other amount of dampness alternating with a smaller amount way, and may then be continued by coal dust, is there of dust. any precaution which could be taken except to water6593. In the other part of the road was there any I am assuming that high explosives are used in such a evidence of a considerable quantity of dust P-Yes. So mine already ?-I think the number of persons emfar as I am aware the only point between the pump ployed ought to te limited to a minimum, so that in corner and the seat of the shot where there was any case an explosion did occur the loss of life would be as damp was at the bottom of the incline, which would small as possible. I think the shot-firing ought to be be about 350 yards from the shot. There was water on done by some competent and responsible official, and the flat sheets at the bottom of the incline, and it as far as practicable, by electricity instead of by fuse. would be damp for a certain number of yards-30 or 6608. When you say as few people should be em40 I believe-from that point. ployed as possible, you mean, I presume, at the 6594. How do you imagine that the explosion got moment of the shot firing ?-As few people as pracover that damp part P-There were some tubs standing ticable should be in the mine at the time of blasting. with coal just on the outer side of that damp part, and 6609. Do you think, consistently with the efficient in my opinion the force of the explosion caused some working of the mine, the shot firing could be carried out of the coal dust on those trams to be disturbed and it on that principle ?-It was done so in the Manchester becoming ignited carried the flame further out to where district when I was in that district. dust again existed on the roadway. 6610. The shots took place before the general 6595. Was the shot which caused the explosion an working began P-All shots were fired in such mines overcharged shot P-For the work that it did it was an between the shifts or after the men had gone out. overcharged shot. 6611. Does that cause no delay in the working ?-It 6596. There was very little rock brought down by it, was found to be practicable there. wtas there not P-A very small quantity. 6612. (Sir William Lewis.) Referring to your report, 6597. Have you had any other experience of explo- which has been confirmed by the evidence we have had sions which could not be traced to the existence of fire- this morning, it appears that a shot had been fired a ,damp P-About 25 years ago when I was connected couple of hours before the shot which may be described with a mine in Germany (Westphalia) we had an as having been fatal P-It appears to have been the case. explosion in which I think it was six or eight men lost 6613. How do you account for that shot having been their lives-I forget exactly the number. Although the stoppings were blown out and they were not re- fired without any disastrous results, while this shot placed for several weeks no trace of fire-damp was under practically the same circumstances created an found in those workings. At the time it was considered explosion P-That is one of those things that I do not to be an explosion of fire-damp as the seams generally think can be explained. If one takes the large number of shots that are fired in the mines in the kingdom, and in the colliery gave off fire-damp. It was a dusty coal, and going back as far as memory will permit me, I the small number which ultimately result in explosions, should now be inclined to think that dust was probably it can only be that the circumstances were exceptional and just such as to suit the occasion. I can in no othe I in a great measure the cnuse of it. way account for it. 6598. Did you take any steps after the explosion at 6614. What could have been exceptional, assuming Camerton to test the mine for fire-damp P-lI accompanied Professor Dixon, Mr. Stokes, and Mr. W. N. that the dust was on the roads and on the sides at the Atkinson, two of my colleagues, in the mine, and we time of the first shot ? That shot was fired without tested, with Professor Clowes' hydrogen lamp, and also any disastrous results, and two hours afterwards a shot with Mr. Stokes' patent lamp, but. we found no trace was fired in the immediate neighbourhood with the fatal effects that you and other witnesses have described. of fire-damp in the air, not even the minutest particle. Subsequently the ventilation was cut off from the whole How do you account for it P-The difference between of that district (above the bottom of the incline), and it the two shots of course is that the one did its work, and remained shut off for about a fortnight. When opened that in the case of the other, the work was reduced to I was present at Professor Dixon's request, and a good a point below what it was intended to do in consequence deal of black damp was given :ff, but there was no of a joint in the roof which cut it short. 6615. Is that the only difference that your practical indication whatever of fire-damp. 6599. Then I understand that it i s your opinion that experience can suggest to the Commission P-Yes, that this was purely a dust explosion P-In my opinion .is the only point which presents itself. entirely so. 6616. The difference between a shot that has done 6600. Therefore you would say that there is danger its work and a shot which may be described as a of such an explosion even in a mine in which no fire- blown-out shot P-It is not a blown-out shot. d~ p has ever been known P--That is so, distinctly, 6617. I will refer to your report, if I may be persince this explosion. mitted to do so. " The shot-hole was commenced a 6586. Did you find on that occasion any trace of fireMr. J. S. Martin. damp ?- None whatever. Safety lamps were totally MINUTES " foot on one side of the centre of the incline and about " seven inches up in the roof, but it rose about four it " five inches more in its length of ten inches, and to " was evidently intended to rip down a length beyond " the end of the hole, but was cut off from doing so by " a joint three inches beyond which Hawkins must " have failed to notice. The result of this joint was " that the hole, otherwise a very short one, was with " half to three quarters of a pound of powder over" charged." In other words that is a blown-out shot -It did not do its work: it was charged beyond what was necessary for the p)articular work intended? .- It blew down to the full length of the hole. 6618. Did you examine the hole as to the amount of powder'that was in it P-It is fair for me to tell you that the evidence we have received from the fireman was that there was 7 or 8 inches of powder, and that it was more than twice as much as he would put in -he said about 2 inches, I think, and Mr. Garthwaite said about 4 inches; what do you say P-That is whet I consider would have been about in the hole. 6619. What P-About the 4 inches; that is the calculation I made there, that about 31 to 4 inches of powder in the hole would make from about half to three-quarters of a pound. 6620. I wanted to draw a distinction between a shot doing its work and a shot such as you have described as being an overcharged or a blown-out shot P-It is an overcharged shot for the work that it did, but not for the work that it was intended to do, 6621. Did it or did it not blow out P-No, it blew down to the end of the hole, and 2 or 3 inches beyond it. 6622. Did it also blow out so as to ignite the dustthat is your suggestion, that it ignited this dust, and that that was the cause of the explosion P-That is the only explanation I can give. This plan will show the position. 6623. The Commission have had before them a section showing the position of the previous hole-that was there, was it not (pointing to plan) P-Yes. 6624. That was set off two hours before P-It was explained to me so. 6625. There was dust on the bottom and dust on the sides as described by previous witnesses when the shot was fired; how do you account for that shot not firing up this dust if dust was the cause of the subsequent accident P-I cannot explain it any further, than that the flame did not catch it as it were at the point suitable for ihe purpose. 6626. Do you think it is possible that the first shot may have relieved any gas from the strata, either above or below the seam P--No. 6627. And that that was set fire to by the subsequent shot P-No, I am perfectly satisfied in my own mind that fire-damp has had nothing whatever to do with that explosion at Camerton. I was very sceptical of it until after I had investigated the whole thing. One of the first things I said to the manager on going down with naked lights and going into the workings 2,100 yards, was that I thought it was exceedingly reckless. 6628. To work with naked lights P-To have gone in straight away after the explosion with naked lights. 6629. Did you inquire as to how frequent blown-out shots were in that colliery P-I think I heard that they occurred very seldom-that they were rare. 6630. Rare in the main ways, or rare in the faces PI understood generally. 6631. You did not ascertain whether there were more blown-out shots in the faces than in the main ways P- No, I did not. There has not been, I understood, a great deal of blasting in the main ways. 6632. In reply to the Chairman, you said that flameless explosives only should be used; would you lay that down without reference to the quality of the dust or the extent of the dust in the particular vicinity of the shot that is about to b6 fiTedP--If dust were present I certainly would. 6633. Without reference to the inflammability of the dust P-Yes. 6634. You would draw no distinction between the dust of one seam and the dust of another seam of coal P -No, I think not. OF EVIDENCE. 6635. Would you draw any distinction between dust pure and simple, and dust mixed with fine shale ?-No, inaslu lch as if you allow it to be left to anyone's judgnLent, then the difficulty at once creeps in as to drawing a distinction; and again, if I remember correctly, I have seen the extension of flame with a dust which was non-combustible. 6636. (Chairman). You said non-combustible, but I suppose you mean non-fiery P-Non-fiery. 6637. If it was in flame I suppose it must be considered to be combustible P-It extended the flame ; it was an experiment of Sir Frederick Abel's with calcined magnesia. 6638. (Sir William Lewis.) You are referring to dust mixed with shale, and to dust of pure coal P--I would not draw any distinction between those two 6639. So if you had an explosion, such as this is alleged to be, in the main way where there is dust pure and simple, and you had blown-out shots in the faces where they say the dust is mixed with shale, and without any accident, you would still think it was necessary to take the same precautions in the face as in the main ways-that is what I understand ?P--With fine dust, yes. 6640. With fine dust without reference to its being shale and coal, or simply pure coal dust P-Yes, I would. 6641. Now with respect to the continuation of the effect of the explosion; you told the Chairman that the explosion was extended by reason of there being a number of tubs of coal with dust upon them in that wet place at the bottom of the incline; do you think that if that train of tubs had not been there the explosion would have been extendel over that wet place ?P--I am not prepared to say that it would or that it would not; I rather think that if it came down there as it must have done with a good deal of force it probably would have extended; but directly over the end of one of those tubs was found against the roof on some of the timber a quantity of charred dust sticking to the timber. That was one of the few places where charred dust was found on the timbers. 6642. Have you considered the matter sufficiently to be able to tell the Commission what extent of damp place you think such an explosion had leaped over as it were P-I have not got sufficient data to be able to give a definite opinion upon it. 6643. I do not know Whether in answering the question of the Chairman with respect to the watering, you had in your mind the various improved arrangements for watering which have been introduced into the steam coal collieries in South Wales-they are partly in your district and partly in Mr. Robson's district ?-Yes, I had got them in my mind. They are perhaps the most efficient watering arrangements that there are in mining; but they do not lay the dust completely. 6644. I was going to ask you that question. Have you anything to suggest that can be done beyond what is being done in the South Wales steam coal collieries with respect to laying the dust or moistening the intake air in the way, say, that it is done at Bedlinog ?-No. 6645. We have had evidence of it from Mr. Martin and others ?-I think the Bedlinog arrangement is very effective. 6646. (Chairman.) That was sprinkling high-pressure water, was it not P-Water with compressed air. 6647. (Sir William Lewis.) You have nothing to suggest to the Commission as a better arrangement, or anything that you would require more than that ?-No, I think that is as effective as it can be; but I think it is impossible to thoroughly damp the whole of a mine practically. 6648. Then assuming that that arrangement were introduced into the whole of the mines, do you still think it necessary to prohibit the use of gunpowder PI should piohibit the use of gunpowder entirely. 6649. Notwithstanding the moistening of the air PYes. 66-50. Would you do that both on the roads and in the face, assuming that the dust in the face was mixed with a very large proportion of shale, as is generally found in the face of this coal ?-I think in practice it would be desirable to; do so throughout. H4 Mi-r. J. S. Martin. fi Mlar. 1894. 64 ROYAL, COMMISSION ON EXPLOSIONS 6651. Have you had any special experience with these flameless explosives; have you satisfied yourself that what is described as being flameless is really so in 16 Mar. 1894. i ractic P-No ; I am not satisfied that these explosives are flameless, but they are very much safer in that respect than powder is. IMy suggestion to the managers in my district is: avoid that which is known to be the most dangerous, and make use of some of those which will reduce the danger to a minimum. 6652. Then do I understand that you would not go beyond the abolition of powder-you would simply abolish powder and let them use any other explosives than powder; is that it P--I have no power of going beyond that. 6653. It is not a question of power. I am asking you your oplnion; you have given this matter your consideration, I have no doubt, and what I am anxious is that the Commission should have the benefit of your experience P-In the very fiery mines if blasting is actually necessary, then I would suggest that it snould ie done when the number of persons employed in the mine is a very small number, so that the risk of life should be as small as possible. 6651. That I understood from your answer to the Chairman; but I want to go further. Does your suggestion to the Commission go beyond that of abolishing the use of gunpowder ? -1 do not quite understand you. 6655. Have you any particular explosive that you-, from your experience and from moving about the collieries in the district now under your control, consider can be used with the least possible risk ?-No,I do not lay myself out to recommend any specific explosive. I may say that since the explosion at the National Colliery I do not like the water cartridge with dynamite. 6656. But whether it is one explosive or the other your opinion is that the risk would be considerably reduced by firing shots by electricity instead of by fuse P-Yes, I think that it would be reduced. 6657. (Mr. Feioick.) Do you happen to know what time elapsed between the firing of the first shot and of the second P--It was merely described to me. The information as to that shot was arrived at from the fireman informing us that from the time the men had gone to their work, or the time that he had been there on the previous day, that shot had been fired and the rubbish had been packed away. We have no information as to the exact time that elapsed. 6658. Supposing two hours had elapsed between the firing of the first and of the second shot, do you think it was possible for the first shot in any way to have started the dust in the neighbourhood of the shot P-Which would affect the second one P 6659. Which might have been in suspension when the second shot was fired P-I do not think si. 6660. With regard to watering, do you consider that the rule relating to watering is generally observed in your district P-I do not think there is much watering ,done specifically with regard to blasting. Mr . J. S. Martin. 6661. May I take it that that is due to the fact that fire-damp has not been found in those mines ?-In those mines in Somersetshire, in the non-fiery mines certainly, watering has not been carried out. 6662. I think you said also that where shot-firing is absolutely necessary it ought to be done at a time when there are the fewest possible persons employed in the mine, and you also told us in answer to a question by the Chairman that in Lancashire this practice had been found to work very well; but is it true that they have a single shift in those districtsP-No. 6663. Is it a double-shift system P-Yes. May I explain. Under the 1872 Act, I forget the exact wording of it, if fire-damp were given off so as to show a blue cap on the flame of the safety lamp, shot-firing could only be done when the persons ordinarily employed were out of the mine. I think if I remember correctly that is about the wording of it. In Lancashire in the Manchester district, of which Mr. Dickinson was in charge and in wvhich I acted for 12 years as an assistant, that was practically carried out. 6664. With the double-shift system P? With the double-shift system, and also where they had the single shift; it was done in both. 6665. Is there any danger, may I ask, of an inconvenience arising to either employers or workmen of FROM COAL DUST IN MINES not being able to get coal, providing that you have to withdraw a number of men before you can fire shots P S--I call only say that in that case they overcame it; they were able to make arrangements which allowed of its being done. The present Act is not worded in the sane way. 6666. (Sir lVilliahn Lewis.) Does that not depend very nuch upon the extent to which powder or other explosives are required in the getting of the coal P-In some of the collieries there they blast a good deal. 6667.' But does your answer not depend very much upon the cxtent to which explosives are required. There are collieries where there are very few shots required, depending either upon the nature of the coal or the ripping of the roof, or the cutfing of the bottonm; thcre are other collieries wlhere the coal requires blasting, where the seams are thin and the top is hard, andc. the bottom also is very hard, and where a very large per-contage of the work of' the collier requires blasting; would that;, or would it not, make any difference in your answer P-It would make a difference in the question of convenience distinctly. 6668. Your answer to Mr. Fenwick with referenice to the Somrnersetshbire portion of your mines as to damping, I lake it, would not apply to the steam coals of IMlonmouthshire; you would not give the same answe that there is no dampinig of or moisture in the air in accordance with the.Act of Pariiament in Monllouthshire PThere is iot a great ldeal of blasting, I think, in the dry and dusty mines carried on during the shift. 6366. Ngo; but as regards the nmister,, of the air in accordance vith the Act of Parliament in Monmouthshire, it is done t) a grea,er extenlt than it is in Somersetshire P-Yes; but I may say that in the Bla-k Vein workings, i which a large naiber of explo-ions have, occurred, iu th . neighbourhood of ltisca anld Abercarn-in that neighbourhood blasting is not carried out at all-there is no blastiiig done. In some of the mines which have been lately op med the question of blasting has arisen, and sonime of tl e mianaoge.s ha ve seen me about it, aid it has been restricted very tiiuch. 6670. Is there any wabirintg done ?--Yes, to some extent. 6671. (Professor Dixon.) Would you call this place where the shot was hred dry and dusty P-Yes. 6672. Now P-Now. 6673. Speaking after the event, that is ?-After the event. 6674. 3Before the event you would not have done so ? -- I am not prepared to say. I was not acquainted with the place before. The part of the same imine which I had personally inspected was very wet. 6675. In your opinion does it come under this section F., rule 12, as a dry and dusty place P-Yes. 6676. So in your present judgment a shot ought not to have been fired there P-That is so, without watering, or an explosive being used which would not fire the dust. 6677. What is your definition of a blown-out shot ?In which the stemming is blown out and the shot-hole remains unimpaired. 6678. Woud you describe the hole as it was found P -The one half remained in the roof and the other half of the hole was blown away. 6679 It was opened up then to at all events one-half its length?-One-htlf of its circumference. It was blown down for the fill length of the shot-hole, but half of the circumference remained. 6680. (Sir William Lewis.) That is to say a semicircle P-That is so. 6681. (Professor Dieon.) My recollection of it is this: that the rock below was blown down to the full length and even beyond the shot-hole ?-Three inches beyond, to the joint beyond. 668"2. Therefore it was not a blown-out shot according to your definition P-No. 6683. Is it possible to tell exactly how much powder was in the hole P-No; it can only be taken from analogy, you may say. 6684. Sir William Lewis asked you whether there was any difference between the two shots to account for the first not firing the dust, and the second doing so. From your knowledge of firing shots in coal mines would you not say that when little work is done there MINUTES OF EVIDENCE. 65 6703. Mr. G arthwaite said they were close to is always more flame than when more work is done ?PMr. Robert's Dipple P-Yes; I described it merely roughly J. S. Martin. I understood that I had explained that to be my viewbecause it is not actually marked on the plan that I that in the one case the shot had done its work, and the flame would not be as great as in the other case where have gouiwhere the roads were. 16 Mar. 1894. the amount of work which the shot did was so small 6701. You have had considerable experience, I that a large body of flame arose from it. suppose, in testing for fire-damp in mines P-I have. 6685. There must have been much more flame in the 6705. What per-centage of fire-damp do you feel sure second case than in the first P-Very much I should think. that you could detect in the ordinary way r-I am afraid I could not answer that of my own knowledge. 6686. And it is to that difference that you attribute the explosion in the second case P-That would be what I have never chemically examined the fire-damp. I have seen a cap of about an eighth of an inch, but I I intended to convey., 6687. Can you tell us by any measurements that you personally cannot say the actual per-centage. have made what length of damp road was jumped over 6706. When you examined the mine after the anywhere by thb flame P--Not by measurements of stoppings were opened, did you use Mr. Stokes' lamp P my own. -No. 6688. Of anyone else's P-At the bottom of the 6707. An ordinary Davy lamp ?- Ordinary lamps; incline there was water on the flat sheets, and I was told they were extinguished immediately when put in the that the distance that would be damp was about 30 current. yards. I think that is mentioned in my report. 6708. You examined not only the road between the 6689. But there was a special circumstance there, stopping and the face but the face itself P-Yes. namely, the presence of coal in tubs P-Yes. 6709. Then in your judgment, if there had been any 6690. Which might have accounted for the flame gas in this pit at all, where would it have been found passing over it P-Which I consider assisted in carrying after the explosion; would you expect any to have the flame forward. been found P--I should have expected it to have beer 6691. But now coming further out beyond the pump found in the return, and I should have expected it to have been found beyond the shot near the face. corner there were some patches of damp road there PBetween the pump corner and the horse gug, there 6710. Would you expect any to be found in the caviwere, I think, three wet patches. ties of the roof ?-Yes, in any of the high places; I should 6692. Can you give us the length of those or any one have thought that some would very likely have been on of them P-I think I remember stepping one of them the top of some of those falls on the road in. somewhere between 30 and 40 yards. 6711. Some of which were a very considerable height 6693. That was thoroughly damped P-Yes. above the road ?-Yes, I should think some of them 6694. Wet under foot P-Part of it was wet under were 10 or 12 feet above the road. foot. It would be then damp on either side without 6712. Possibly you would expect any gas, if such dust. existed, to be found at the entrance of this old road 6695. And in your opinion the flame must have gone which is near the shot P-In any of' the cracks of the over that damp place P-I cannot speak with regard roof I should have expected it. to the flame. I think that consumed dust was con6613. Which way drawn out veyed past it, judging by the film of dust which I saw from that old road if would air have been at all any air was out lying there when I arrived, but as to the actual fact it by the ventilation of the mine drawn would be or into P-It drawn of flame having passed I have nothing to guide me. away from it. 6696. How far, in your opinion, did the flame extend 6714. (Sir William Lewis.) Into the current out of the outwardsP--I have here some of the dust (producing specimen). This was sent to me by Mr. Atkinson; it goaf into the main ways P-Yes. was taken up at the time of our inspection at about 6715. (Professor Dixon.) So that entering that old 100 yards on the inner side of the pump corner, and road if any gas was in that old goaf you would expect when examined under the microscope (which I did to find it just inside the entrance P-If there was any this morning) it clearly indicated a globular condition gas there I should have thought that that would have as though it had been coked. been the place; it was a dead road or comparatively so, 6697. May I correct you for one moment. Did you not refer to inside the horse gug P-No, 'that was 6716. It only goes about 10 yards in; you will see collected half-way between the branch and bottom of it upon this plan -It was stowed up to within 2 or the incline. 3 yards of the road. This is the working. 6698. (Sir William Lewis.) You say in your Report, 6717. You may remember that we could not get into as Professor Dixon suggests: "My colleague, Mr. W. " N. Atkinson, however, having examined under the it P-It had been stowed up. 6718. Do you remember the circumstances of the " microscope some of the dust which he collected from " the side of the road 100 yards inside the horse gug, Malago explosion ?-Yes. " informs me that it clearly showed that some of it 6719. What was your opinion at the time with regard " had been in a state of incandescence, and the same to that explosion-I mean with regard to the dust " would appear to have been the case all the way, carrying on the explosion up the incline P-I considered " from that point in to the shot." Do you wish to the dust had carried it forward a good deal; it was a qualify the statement in your Report P-Mr. Atkinson fire-damp explosion, but the extension of it was due has read this Report and has not corrected it, so I more or less to dust. That was my opinion at the presume that it must be correct, that I am right, and time. that this other specimen refers to something else. modify that 6720. 6699. If that is correct the flame must have passed opinion Would you be at all inclined to played a still now and consider that the dust over those 30 or 40 yards of damp place which you more important part in that explosion P-I think it paced P-Yes ; in my opinion it did do so, but I have played a very large part in it. In that case I may say not got any data which actually enabled me to specifi- that the force and the flame travelled with the air cally say so. current in the return; it did so in the case referred to 6700. Proof which you yourself saw P-Which I as having occurred at the Ludlow's Pit of the Radstock myself saw. The film of coal dust led me to believe Colliery. that it was so. 6721. It did not follow the air current through the 6701. In your experience of explosions in coal mines would you say that there was less evidence here of levels on each side of the incline; it only went a short flame, less charring and less dust, than in those you way, if I remember rightly, into the workingP-It went have previously examined P-Generally speaking it is in one of the levels, I think a couple of hundred yards, so. As regards the amount of charring I may say that but we had not got very distinct proof of it. I think at the Malago explosion, except in the vicinity of the there was a brattice sheet, or a door, that showed it on one of the intermediate levels, but as a rule it did not seat of the explosion, there was not much charred dust go very far into the workings. on the timbers. 6702. You said, I think in answering a question, 6722. So that it did not follow the air current all the that the stoppings after the explosion were put in near way but it went straight up the incline P-The incline the bottom of the incline P-On the outer side. was the main return current. The witness withdrew. E 82480. 66 Prof.H. Dixon. ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES: Professor HAMOLD DIXON (a member of the Commission) examined. 6723. (Chairman.) I think that you have made a 16 Mar. 1891.' great number of experiments in testing small percentages of fire-damp both in the laboratory and also in some of the pits P---I have made a good many experiments, I will not say a great number, but a good many 6724. In these experiments what apparatus have you used P-I have used the ordinary Davy lamp, and I have used one or two of the more modern lamps which are at present used in the Lancashire and Yorkshire district; I have especially used Professor Clow es' hydrogen lamp. 6725. By means of that lamp what is the smallest per-centage of fire-damp that you have been able to detect ?-I have been quite sure of one quarter per cent. 6726. Of course one quarter per cent. is a quantity that is not explosive ?--Not at all, and it is not indicated by an ordinary lamp. 727. Did you test the air at the Camerton Colliery after the explosion P-Yes, I tested the air at two places in the returns, and I tested it at several places in the intake, especially in the cavitie3 in the roof ; wherever we found a considerable fall of roof I climbed up as high as I could and tested close to the roof. I also tested at the entrance to this old road coming from the goaf which is close to the spot where the shot was fired. 6728. Did you test the working face P--I also tested at two places in the working faces. 6729. All these testings were made with Clowes' hydrogen lamp ?P-Yes, all. 6730. What was the result P-I could detect no gas whatsoever. 6731. In your opinion if there had been even so little as a. quarter per cent. you would have detected it P-I am quite sure of that. 6732. Then in the course of this inquiry you have visited several of the scenes of explosions which have taken place ?-Yes. 6733. Would you name which are the cases that you have investigated P-The Apedale Colliery explosion, the Malago explosion, the explosion at Ludlow's pit in the Radstock district (that was a blown-out shot which fired dust and burnt a man, but no loss of life ensued), the Park Slip Colliery explosion, and the Camerton Colliery explosion. 6734. Have you prepared any report on the result of these investigations P-I have written a short report on what I have myself seen, and the conclusions that I have drawn. 6735. Will you kindly put it in P-I will. 6736. (Sir William Lewis.) May I ask what modern safety lamps you refer to as having applied as a test for gas P-Yes, I used Mr. Stokes' alcohol lamp, the Pieler lamp, the Marsaut lamp, and one or two others. 6737. I am asking you now because there is a lamp that is very generally used in South Wales. I do not know whether you have tried it; it is called the Evan. Thomas lamp; it was one that gave very satisfactory results in the experiments of the Mines Commission ?I have tried it and also the Thotnmburry and the Hepplethwai te-Gray. 6738. With respect to the test that you made of what you found in the cavities, did you find any difference at all in the cavities there P-I found no difference. Conclusion of the Evidence. 67 APPEN DICES. LIST OF APPENDICES. No. Subject. Page. XIII. Extract from the Report of the Austrian Commission. 68 Table showing the effect of a blown-out shot of gunpowder upon the chemical composition of the atmosphere. Handed in by Mr. James Ashworth. 69 XIV. XV . Six Diagrams, &c., to illustrate the Compressed Air System of Watering. Handed in by Mr. H. W. Martin. XVI. Three Diagrams to illustrate the case of a blown-out shot at Ludlow's Pit, Radstock. Handed in by Mr. J. McMurtrie. Subject. Page. - J. B. 71 XVIII. Mr. Henry Hall's Report to the Secre- 71 XVII. Letter from Messrs. W. N. Atkinson. tary of State for the Home Department, on experiments with coal dust. /XIX. Mr. Henry Hall's Report to the Chairman of the Commission, on further experiments with coal dust. XX. Two diagrams to illustrate the evidence on the explosion at the New Pit, Camerton Colliery. Handed in by Mr. J. S. Martin. XXI. Report on various explosions, &c. Handed in by Professor H. B. Dixon. 12 75 91 68 ROYiAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MI>NEo: APPENDIX XIII. ABSTRACT OF PART OF THE FINAL REPORT OF THE AUSTRIAN FIRE-)AMP COMMISSION. PART III. Coal Dust. The experiments made by the Austrian Commission confirm those made at Neunkirchen and Zwickau with regard to the danger of coal dust, but also show that the dangers are far greater than have hitherto been admitted. First of all, the Commission tested the different kinds of coal dust, so as to classify them according to their sensitiveness to ignition and their danger. As they considered that black powder and similar explosives are dangerous in fiery mines, and that their use should be entirely prohibited, they confined their experiments to high explosives, especially dynamite No. 1. The experiments were made in a level like the one at Neunkirchen. Each kind of dust that was used was also tested in order to determine the following facts concerning it:1. Per-centage of volatile matter. 2. Hygroscopic moisture. 3. Per-centage of ash. 4. Quantity of marsh-gas in 100 grammes of dust. 5. Quantity of gas given out by 100 gr. of dust at 1000 C. 6. Composition of gas given out by 100 gr. of dust at 1000 C. Instead of imitating blown-out shots, the experiments were mostly made with cartridges of dynamite lying loose, or with a slight covering of coal dust. The coal dust experiments were almost exclusively made without any admixture of gas. In all 353 experiments were made with 345 kinds of dust. These experiments showed that many notoriously dangerous dusts were less inflammable than other less dangerous dusts. Coal dusts were therefore classified into sensitive and dangerous kinds. To judge of their sensitiveness, coal dusts were all tested with the same charge of dynamite, viz., 100 grammes. The experiments showed that without any admixture of firedamp, nearly all kinds of coal dust were ignited by a cartridge of 100 grammes of dynamite lying loose. To ascertain the relative dangers of the different kinds of coal dust, the lengths of flame were noted, and such as gave a flame 15 m. (49 ft.) and over, in length, were omitted as specially dangerous. The experiments made with a small admixture of fire. damp proved that such an admixture notably increased the danger and sensitiveness of the coal dust. The degree of inflammability can scarcely be deduced from the chemical composition. The texture of the coal is important. Hard compact coal will give less dust than crumbling friable coal. The fineness of the coal dust depends upon its texture. The sensitiveness of a coal dust and, as a rule, its danger increase with its fineness. The sensitiveness of a coal dust and, as a rule, its danger increase with its dryness. The danger of a coal dust appears to depend more upoih its physical qualities than upon its chemical composition. A blown-out shot with coal dust as tamping, or a charge of dynamite lying free will ignite every kind of coal dust. 'Most kinds of coal dust were ignited with a charge of 100 gr. (31 oz.), and all without exception were ignited with a charge of 300 gr. (10J oz.). A coal dust which otherwise is not dangerous and takes fire with difficulty may give rise to a disastrous explosion if there is a little fire-damp present. Means of preventing the Danger of Coal Dust. 1. Watering.-This is undoubtedly useful, but it cannot guarantee thorough safety unless all the roadways and working places are watered and all parts of them, including the roofs and sides. Such a watering could not be effectively carried out without very great difficulties, indeed the difficulties might be insurmountable in some cases, 2. Removal.-Sweeping out the dust where shots are fired is troublesome and will rarely be properly carried out. 3. There should be no unnecessary exposure of the coal by roadways or workings, because all these help to dry up ,the coal and favour the production of dust. SAn excessive ventilating current in dusty mines must be injurious on account of its drying the dust and the coal. 4. Blasting is the greatest source of danger in dusty mines. The water cartridge is useful, but its efficiency is dependent upon the conscientiousness of the workmen. Galloway's moss tamping is more practical. These objections have led to the introduction of an explosive having salts containing water (carbonate of soda, Epsom salts) intimately mixed with it, and called " Wetterdynamite." T'Ihe Wetterdynamitr, used at the Wilhelm Pit, Ostrau, was a mixture of 52 parts of nitroglycerine, 14 parts of infusorial earth, and 34 parts of crystallized carbonate of soda. The experiments at Ostrau have shown that black powder and its congeners are highly dangerous for fiery mines in which there is coal dust. Even in water cartridges these explosives do not give sufficient safety. Neither do dynamite and its congeners, such as blastinggelatine and gelatine-dynamite. A sufficiently large charge lying loose will ignite most kinds of coal dust. These high explosives must therefore be called dangerous. However, if the charge is covered with a sufficiently thick layer of sone uninflarnmable substance, it will not ignite explosive mixtures of fire-damp and coal dust. Therefore, by the addition of a comparatively insignificant means of protection, these high explosives can be made safe. This is not the case, except as regards Wetterdynamite, with the less powerful explosives such as gunpowder. The Ostrau experiments show that the Soda-wetterdynamite, of the composition given above, is superior to all other kinds of Wetterdynamite tried. Loose charges of Soda-wetterdynamite weighing 500 gr. (1 lb.) did not ignite the most dangerous coal dust in the absence of firedamp. Charges of 150 gr. (51 oz.) would not ignite an explosive atmosphere with 9 per cent. of fire-damp, with or without coal dust. A charge of 200 gr. (7 oz.) would always ignite an explosive atmosphere with 9 per cent. of fire-damp, but not one with 7 per cent. The latest experiments at Neunkirchen show even a higher degree of safety. Soda-wetterdynamite can therefore be regarded as an explosive offering great safetyin fiery mines, even if there be coal dust present. At Rossitz loos6 charges of Soda-wetterdynamite weighing 150 gr. (5 1oz.) gave explosions with a 6 per cent. mixture of fire-damp and air, without any coal dust; but where no gas was present charges of 300 gr. (10 oz.) were fired without any explosion. The Rossitz results are less favourable than those at Ostrau and Neunkirchen; this may be explained by the experimental explosion chamber at Rossitz being very much smaller than the one at Ostrau. Although the discovery of Wetterdynamite has rendered special safety cartridges of less importance than they were before, new proposals have been made in this direction, and they have been put to the test by the Ostrau local committee. One of the simplest and safest is the canvas-sand cartridge. The dynamite cartridge is enveloped in a case of coarse canvas which has a layer of sand about 1 mm. (one twenty-fifth of an inch) thick glued over it. -It is dipped in water before being used. Experiments made in an atmosphere containing 9 per cent. of fire-damp and coal dust with cartridges lying loose almost always gave satisfactory results, and showed that with a small amount of protection high explosives can be made comparatively safe in fiery mines. A reliable Wetterdynamite seems the safest means of retaining blasting in dusty mines. 5. A safe explosive becomes unsafe if a dangerous mode of firing is adopted. In the Austrian fiery mines three methods of firing are in use, Bickford's fuse, electricity, and Lauer's friction fuse. Bickford's fuse cannot be regarded as safe, for it emits sparks. Electric firing is safe enough if it is properly looked after; if not properly attended to, sparks from the machine or badly isolated wires may cause explosions. The safest mode of firing is by Lauer's friction fuse. In spite of all precautions, blasting in mines with firedamp and coal dust present is always critical and dangerous. In special dangerous mines it appears advisable that under certain circumstances blasting should be given up altogether. PART VII. Summary and Proposals. The Commission propose that fiery mines should be classified according to the proportion of fire-damp and carbon dioxide in the return air, assuming a similar amount of ventilation for all mines of 2 cm. per man and per minute (70 cubic feet), or li cm. (53 cubic feet) per niinute and per ton raised in 24 hours. 69 APPENDICES. They propose three classes of mines:1. Fiery mines with little fire-damp, those in which the returns contain less than 1 per cent. of gas (CH 4 + CO). 2. Fiery mines with a moderate amount of fire-damp, those in which the return air contains between 1 and 2 per cent. of gas. The following rules as regards blasting should be enforced in all fiery mines :1. The use of black powder and its congeners should be prohibited except in mines with very little fire-dam. 2. In mines with a moderate or a large amount of firedamp blasting with Bickford safety fuse and high explosives should be permitted only when no gas has been indicated by a sensitive and approved form of lamp (Pieler lamp). If there is a trace of gas, no shot must be fired except with the permission and in the presence of an official. If the per-centage of gas reaches as much as 1 to 1i, the shot must be fired with the Lauer friction fuse or 3. Fiery mines with much fire-damp, in which the return air contains more than 2 per cent. of gas. Mines should have two shafts or outlets, If the two outlets are in the same building, they must be separated by a fireproof partition for fear of the two shafts being endangered by a fire. The free and clear section of ventilating shafts and compartments shall be large enough to allow the requisite some other approved fuse. amount of air to pass through with a moderate velocity, not exceeding 6 m. (20 feet). If the per-centage of gas in the ventilating current is 2 to 2-, then only duly tested explosives (Soda-wetterdynamite of the composition 52 per cent. nitroglycerine, 14 per cent. infusorial earth, 34 per cent. crystallized carbonate of soda) must be used. No other explosive to be used without the permission of the authorities. If the per-centage of gas in the ventilating current is 3 to 3', then no blasting must be done. Tamping with wet sand is recommended. Then follow sundry regulations for securing adequate ventilation in all sorts of working places. Ventilation.-Class I. Little fire-damp, 2 cm. (70 c. ft.) per man per minute, reckoned on the greatest number of persons in the mine at one time. Class II. Moderate amount of fire-damp, 3 cm. (105 c. ft.) per man per minute. Class III. Much fire-damp; at least 4 cm. (141 c. ft.) per man and per minute. Division of mine into parts, and not more than 100 persons to be in one part. Downward ventilation to be allowed only in exceptional cases. Numerous other regulations. Lighting.--Safety lamps to be obligatory in all mines pronounced to be fiery mines. Mixed lights to be allowed by special permission in mines under Class I., in which there is little fire-damp, where the gas comes off only in a few working places and sporadically. It is not necessary to prescribe any special kind of safety lamp. But lamps other than the Mueseler, Wolf with two gauzes, and Marsaut should not be used without permission of the Government authorities. Sundry other regulations about safety lamps. Blasting.-This is one of the chief causes of accidents in mines containing fire-damp or coal dust. Blasting may cause accidents in two ways :1. By the fuse. This source of danger may be got rid Coal Dust. - Wetterdvnamite gives almost absolute safety in blasting in mines even with the most sensitive coal (lust. In fiery mines with much coal dust, the following rules should be observed:The workings should be divided into districts or parts with separate ventilation. All connecting roadways should be shut off securely and kept free from coal dust. These connecting roadways should in part be lined with brickwork or masonry, and any loose coal dust which might collect there should be rendered harmless by watering. The same precaution should be taken in all main roadways and haulage ways. If much dust is found in working places, blasting with high explosives must only be allowed when the coal dust has been completely removed for a distance of 10 m. (32 ft.) from the shot, or has been thoroughly watered. If this cannot be done, blasting must be given up or a safety explosive, such as Soda-wetterdynamite, must be used. If, in addition to coal dust, there is an emission of firedamp sufficient to give - to 1 per cent. in the ventilating of by using Lauer's friction fuse. 2. By the explosive. This source of danger is specially present with black powder. With the high explosives like dynamite it is principally a blown-out shot that is dangerous. Water cartridges and safety cartridges require much care, and it is not easy to ensure their being properly used. The safety obtained with Soda-wetterdynamite is very great and almost absolute. No doubt other equally safe explosives will be discovered. current, the shot must be lit by the Lauer fuse or some similar fuse. If there is as much as 2 to 2- of fire-damp in the ven- tilating current, then blasting must be given up altogether. No blasting should be done except in the presence of an official. The concluding proposed regulations relate mainly to the staff of officials. C. LE NEvE FOSTER. Llandudno, 30th July 1891. APPENDIX XIV. (See Minutes of Evidence, Question 4625.) Handed in by Mr. James Ashworth. Case A.-The atmosphere of the mine is supposed to consist of 1 volume of fire-damp, 14 volumes of air, 54 grains of aqueous vapour, 7*3 per cent. of coal dust by weight, and the resultant gases from 1 lb. of powder, ccmposed of saltpetre 66, sulphur 10-5, charcoal 23"5. Case B.-The atmosphere is as in Case A. with the substitution of 1 lb. of Karolyi's powder for No. II. Karolyi exploded a charge of powder composed of saltpetre 73' 78, sulphur 12"80, and carbon 13- 39 in an iron cylinder of such strength that it would just burst when the powder was fired. This cylinder was enclosed in a hollow spherical bomb and the air exhausted before firing by an electric spark. The resultant gases and solids were as follows:- S Weight. I Volume. I -- IVolume. GAs. Nitrogen Carbonic acid Carbonic oxide Hydrogen Sulphuretted hydrogen Marsh gas SoLID, Ammonic sesquicarbonate Potassic sulphate carbonate ,, hyposulphite ,, sulphide ,, Charcoal Sulphur Loss - - - - - - - - - - - - - - - - - - - - 9 77 17-39 2.64 - 37*58 30*58 0-11 0-27 I 0-40 J 2*68 36-95 19 40 2* 85 0*11 2-57 4*69 k 5*95 0*86 2*70 69*25 '017 100 -o00 I 42-74 10" 19 I 100-00 x The gas contained a sufficient quantity of carbonic oxide, hydrogen, and its compounds to take fire on the application of a lighted match. I3 70 ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES: BEFORE ExPLOSION. Case A. Per Cent. ) Fire-damp Air Water - - Coal dust . - Volume, Litres. CH4 O0 Weight, Grammes. o '067 x - 81 H 5 2 10 2 N O0 Ash 0 0452 x 0*2530 x 0'8854 x 0*0126 x 0 *0691x 0'0044 x 0'0015 x 0"0088 x 0'*0044 x 1"00x 0 "187x 0 •746 x N HzO20 c - Case B. - Weight, Grammes. Volume, Litres. Cent 0'0452 x 0'0452 x 1P0x 1"1384 x - 0'0126 x 1 1384 x 0*0126 x 0'0882 x - 0'0882 x 100 Powder - { KN03 299-4 1 47'4 r 106-8 J 66'0 10'5 23'5 S C 73*78 12*8 13'39 453'6 453'6 AFTER EXPLOSION. Case A. Case B. I Per Water in air from CH Ditto from H ofcoal dust CO from CI 4 C() from coal dust CO from powder N from air - - - - N from coalduist N from powder CO from pcwder Ash from coal K2 S from powder Ax2S,. H ,, ,, - 0'0126 x 01017 x r 0 1539 x 0 0396 x 0 x0791x0'2403 x 0"1612x 249'1 249'1 0'885lx 0'8869 x 0'0015 x 41 5 41 "5 - Ditto 0"067x 0'136 x 210 0 74;i x 0"203x 00 210 0747x 0"001 x 34 99 _ - j 7 3 99 0'0044 x 1-63 1 0'1539 x - 0"203 x 210 210 CO , from powder CO 2 from CH 4 of powder Water from above Ditto from H of powder 78 9 0'0044 x 0"5 1'2 0'5 2*6 26 1"8 1s Case B. 0'3776 x 391*4 0 1539 x Volume, Litres. 0*3776 x 0-203 x 101 1 42-3 2-6 391-4 0'203 x 52"4 2"6 0*1539 x Ditto from H 2 S of powder Ditto fromo CH4 of powder SO 2 from H2 S of powder Ash from coal N from air - 0-747 x 34-99 N from powder Ammonic sesquicarbonate K 2 SO 4 - - ,CO K 2 K 2S 2 0 3 KS 0"747 x 34.99 0*0044 x 0*8869 x 41-5 0747 x 37-3 0* 747 x 37.3 - - - - ,, - 190 78*9 4.9 0"1539 x 4,5 0*6 1-63 , 0 101 x 1 63 0"101 x 105 105 x (0*151 x - =the 0101 x 0101 x 18-1 139*99) 44.3 12*1 167-4 88*0 12*9 0"5 11 6 21*3 12*9 0'5 11"6 21'3 (0'151 x - 77-9) vemm 9*1 0*8869 x 18"1 volume of the atmosphere at 150 C. and 760 m.m. pressure. the 4.9 0*1539 x 44.3 12"1 167 4 - Vacuum equals 97.9 0*8869 x for - 0"3776 x 2'2 0 0044 x 88*0 - O taken from external air powder 0'3776 x 0 0044 x 0*0044 x 0*8869 x 41"5 - ,, Weight, Grammes. 4"0 2'2 - 44*3 443 78.9 0'0044 x 0-5 1"2 0'5 OF THE FIRK. Weight, Grammes. 0*203 x - 0'2403 x 12'0 0'8869 x 0"8 5.9 *9 Case A. Volume, Litres. 12'0 .37*'3 37'3 423 42"3 - - THE RETUTRN 0' 203 x 1061 0*747 x - - AFTER CO 2 from above CD Weight, Grammes. 0' 004 t x 1i.3 - O left in atmosphere CH4 from powder Per Cent, VolumEe, Litres. Cent, 1 - - - Weight, Grammes. Volume, Litres. Cent. S m .pre I 0 U) w z H C,, 34 i~E o a (in) o LL oz 34 L~ w Om 0 C,, 0 0 -I 0 -~ r (nj LLI IC z r 0 FI~ C..) 0 U. X O cn .. z 0 q< 0, z 0 0 C) _J A 0> L 3 mdd Ca L , Lith. 6 ,Carter lane, Dootore' Coummns. & 84&..A ROYAL CoMMI sIOH illwitrate jIrJI le ON EXPLOSIONS FROM COAL Du ST IN MINES. o WAfap&et : !.L APPENDIX XV. (d) See Minutesof I-zEwWwe, £-vidce teuo 57. DOW LAl S COLLIERIES. HYGROMETRICAL READINGS WITH MARTIN & TURNBULL'S PATENT COMPRESSED AIR & WATER SPRAY. THE TUNNEL SOUTH PIT, IN HYGROMETRICAL HYGROMETRICAL WITH WATER IN BEDLINOG, HYGROMVETRICAL READINGS. HYGROMETRIC AL READINGS. IN MAI K"BLTU RICN wuwo d e =P -Vw Da &eArw.Fahrdjrrfrf~ INMAIN"RETURN" Vi.WlJ4 of of 12J y we fakr o wtWfw ~zfi.Li1L7 t Spray yf u65 --- 7-- Vl W 1w m Spry 1 ft. 1i-4.per per SIdg Yan 16 54 s. READINGS SPRAY. PIT. N?2 READINGS. An_ A 67,65 65 63 .0 46 586- 16 686666 66 570, -4L 438 ew- -- V si sil .5 6 6 6464- 417 M 7001 ~ O656666 ZJ6#66c66 6 560 t4 7 444 18 18 -9 30854 92Z 10 - ,5- ,01S55 1, 18 SSIa 16 - 44 185 656767 67 di 8i67i6 11 69.9 18- 1. - 6 67679M 810 104634 if-06 M 44 6 "9573"' WAM .~31 '6846666 12 774 18 6i6i64464 DA 6661d67 67 i 61 f 6i m m / o 10 1JZ~9 -13 18 873," -b18 is15 811 6W4 67 67 67 14 W 6Ai 67 67, 1W 6i961667 S16 976 16 17 137Z -17 $6 67,61767 053' le,6 166_9 f67 i67 49 15 ,444-%-- 6 -44 -fac 2 0 6A. 1558 618 -36 -J 67MOO 470j; t6 666 21 1584 4~.631 3 4666 12s ~ 3 di60 6956767 Dow LAIS IRON WORKS. Jv" & C* L-, Uth 6fC~. a, 3J0 - I ROYALCOMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES. APPEN DIX X () I. * To Illustrat M" H. WMartin dence.-. S-e- Mz sfEidmeQuestion. 5377 - UPCAST Airpit DOWLAIS COLLIERIES. Tuanda Soiuth"t.Little in", 61Yds. NA3 Lower than1Pt This Plan, shews the positio (by the consleel-tive runbers)of the Compres~ed-Air & Water SpraEys. SCtale:- 4Caim to an> IrA: 2<" 1 ,~ 424 DOWLAIS IRON WORKS. Fe6 29/t1892 JrddlCo~ L'L ,Lit Lh.63,Carter Lant,ODoctoar'Commons. 36. 5 2 ._.____i-__ -- ROYAL COMMISSION - .ii_-i - ON EXPLOSIONS FROM COAL APPENDIX ---- __________________ XV. = _______ _ - ,------------- J ------------ DUSr IN MINI ES. (f) To illustrate M H.W. Martin's Evidence. See Ninutes of Evidence Question 5377. DOW LAI COLLIERI ES. S -- Li Bc diog Hf z? 14>t r Y, 4 rt* 9f lis Plaits/wts [1e pos r ) /c WdeS V oft 4toenadr- a prays. _I JD N .B9owi wast" . S P 2 rft'OOya;d. 2 . NYtca'st PIT. Sx~oa t 4. Madman 4Ctns Iv a- ............. .&,,6,.,, .. ,,.O .C.... .er. ..... .ts ctor"JI coming, PRS -3436 4 9;1 ,ROYAL CO ROYA COMMISI 10N ON EXPLOSIONS MIS 31N ONEXPOSIOS .IL APPENDIX FROM COAL DUST IN MINES. FOM CAL UST N MNES PLAN N?I. x it a- (To illustrate MWI J. A Murtrie's Evidence. See Minutes of Evidence, Question.6105) PLAN -o RFIL OWER SERIE S LUDLOW S PIT. SHOWING POSITION OF BLOWNOUT SHOT. NOVEMBER 24'~ 1891. eN Md P MIDDLE PIT .iddA 0 I)',t#th 63,Ca,~erL.i~e, 343t. O ~ Si I' -- .ii ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES. APPENDIX PLAN N 2. X\T b. (To illustrate M'J. . Murtrie's Evidence. See Minutes of Evidence, Question 6105.) LUDLOWS PIT. RADSTOCK. SECTION OF SEAM SHOWING THE BOREHOLE. CLIFT. ......... COAL......... INFERIOR COAL. ...---STONE COAL ............ Scale Yovk to the Foot Ju~dd&(' P-If63 C,-,-1- iii All JrdALC I' hl'e EJ C,.- -' l7-1' "93 .4W ______~ ~ 4--~~~-~ ROYAL COMMISSION ON EXPLOSIONS FROM COAL--- "--~ MINES. DUST IN --------XVI APPENDIX C. PLAN NO 3. N0 3. PLAN (To- illustrate! Mf J.M? Murtrie's Evidence. See Minutes of Evidence, Question 6081) --X. PLAN -- O FLOWER SERIES M DDLE P T. SHIOWNG POSITION OF BLOMNOUT SHOT. ---- ------- JUNE OLUDLOWS 1889. PIT 1&9 --------- l-=-_ e N MIDDLE P/T Y ~ ---- . ..;.~... ..... . ... JuooA.4-36 4.82? APPENDICES. 71 A PPEN DIX X VII. Newcastle, Staffordshire, SIR, April 9, 1892. WE have the honour again to address you with reference to the tabular list of explosions published as Appendix IV. to the First Report of the Royal Commission on Explosions from coal dust in mines. In this table the explosions occurring during the 39 years, 1851-89, are classified as follows:-A. Explosions in which, so far as there is evidence, coal dust probably played no part; B. Explosions in which coal dust probably played a part (insufficient evidence); C. Explosions in which coal dust probably played the principal part. The table was handed in by Mr. J. B. Atkinson, when he gave evidence before the Commissioners (Q. 709), together with a chronological list of the explosions and an abstract of the official reports on the explosions. These abstracts were prepared at the request of Mr. Lushington, Under Secretary of State for the Home Department, as explained by him in his evidence (Q. 107 and 108). The table was merely an endeavour to summarise the conclusions which we thought might be drawn from the abstracts, which were relied on to (how the reasons for the classification adopted, and the table was not intended for publication separately. The abstracts were considered too voluminous for publication, and the table has been issued alone. We submitted, for your consideration, in a letter dated the 14th ultimo, that it might be desirable to publish some of the abstracts in ordcr to show the kind of data on which the table was based, and we received in reply a letter from Mr. Wilson, Secretary to the Commission, saying that the Commission " came to the " decision that it was not necessary to publish the " abstracts. In the first place they are very bulky, " and would add unduly to the size of the Report. In " the second place they are ex parte statements, being of " course compiled by yourselves, and would justify " applications for rebutting evidence to be taken in " regard to each of the explosions named. But if you " think that any injustice is done to you by the " publication of your tables without the abstracts, the I " Commission would be happy to insert a letter ad" dressed to them explaining the nature of the corro" borative documents which are omitted." We do not think that any injustice has been done to ourselves in the matter, bat what we fear is that the omission of the abstracts explaining the grounds on which the table is based will deprive the table of its nroper weight, indeed of all weight whatever. For it might be supposed that the results shown therein had been arrived at simply by assuming the question at issue, and attributing chiefly to coal (lust nearly all the great explosions. Whereas the contrary is the fact, each case was separately studied and its place in the table fixed as the result of careful consideration of the circumstances. The abstracts which we prepared, scrupulously distinguish any inference of our own from the reported facts of the case. In the main they consist of some or all of the following particulars, as specified in the official reports of those who made inquiry immediately after the explosion. A brief description of the colliery, such as depth of shafts, name of seam, area of workings, mode of working, method of ventilation, and system of haulage. Evidence as to the presence of fire-damp and coal dust. System of lighting and use of explosives. Where possible, the course of the explosion and its extent is svated; the part of the mine traversed, as working faces, intake air-'ways or return air-ways, and whether the explosion reached the shafts. Evidence as to previous alarm of the workmen is noticed. The supposed point of origin and the cause of the explosion (as stated in the official reports) is given, and any other point bearing on the question of fire-damp or coal dust is noticed. We have the honour to be, sir, Your obedient servants, W. N. ATKINSON. J. B. ATKINSON. The Right HIIon. J. Chamberlain, M.P., Chairman of the Royal Commission on Explosions from Coal Dust in Mines. _ APPENDIX XVIII. Rainhill, Prescot, 23rd January, 1893. I HAD the honour to submit to you in October, 1890, the result of some experiments, carried out on a large scale, to test to what extent colliery explosions may be due to blasting with gunpowder, in colliery workings SIR, which are dry and dusty, and in the entire absence of firedamp. At that time, although the experiments were perfectly conclusive to myself and the several gentlemen who witnessed them, there were certain aspects of the inquiry to which others took exception. The nature of those objections may be gathered from the evidence given by different witnesses before the " Coal Dust Commission," but this evidence was very scantily supported by any actual knowledge or facts, and was in many cases mere guesswork. I have now the honour to report the result of further experiments carried out on three separate days under much the same conditions as the original experiments, but directed specially to the points upon which doubt still seemed to exist, and I think the result cannot escape being accepted as conclusive-that dry coal dust, under conditions frequently present in coal mines, and in the entire absence of firedamp, may be inflamed by a blowing-out gunpowder shot and cause a disastrous colliery explosion. This series of experiments was made in the same pit shaft as on several previous occasions. It is 50 yards deep. Seven feet diameter, with struts of timber fixed every 6 or 7 feet at the sides of the shaft, from top to bottom, to represent bars and timbering underground, and to afford a lodgment for dust. The shots of gunpowder were fired from a cannon 3 feet long with a bore 2 inches in diameter and fixed at the bottom of the pit; the shots were fired by electricity. The pit shaft was very wet, and the struts of timber had to be scraped partly dry to enable the experiments to be carried out. Experiments of the I Ith June, 1892. Weather, wet and damp. Temperature on the surface, dry bulb 53o, wet bulb 530. Temperature at the bottom of the shaft, dry bulb 570, wet bulb 560. Present : Mr. W. N. Atkinson, Her Majesty's Inspector; Mr. Southworth, Mr. Bigg-Wither, Mr. Aspinwall, Mr. Lea, Mr. Wall, and several miners. 14 72 ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES: -No. of lExperiment. Weight of Gunpowder. -- Quantity of Dust. Description of Dust. Description of Dust. Result and Remarks. -- I 1 lb. None 1I lb. None - 11 lb. None - 1I lb. 2 cwts. 72 lbs. White Moss screens. A quick violent explosion, and flame projected high into the air at mouth of pit, causing great damage to staging. Half the dust was put in to sop up the wet in the shaft and allowed to go to rest, then the other half put in and the shot fired a minute later with dust in suspension. 1 cwt. Hindley Green return air-ways. No explosion of dust. The cannon was fired 1-i minute after the dust was put down, with dust in suspension. j lb. 5 J No unusual violence or flame. These three shots were fired simply to show the amount of disturbance in the absence of dust. No explosion of dust. The dust was entirely at rest, and air in shaft clear. cannon was fired one hour after No. 5 experiment. No fresh dust put in. The l4 lb. I cwt. 22 lbs. Hindley Green screens. Violent explosion, and flame projected at mouth of pit. The cannon was fired 1 minute after putting dust down, and was still in suspension. l4 lb. 1 cwt. 12 lbs. Hindley Green screens. Dust apparently caught fire and went out. The cannon was fired four minutes after putting the dust down, very little in suspension. 11 lb. 4:lb 1 cwt. 20 lbs. White Moss screens. No explosion of dust. The cannon was fired 21 minutes after putting the dust down, and some still in suspension. 6 7 The results of this day's experiments were similar to those of the original series, but it must be noted as important that No. 4 explosion of dust was produced with that from White Moss Colliery, Arley seam, whilst in the original series Hindley Green dust played the most conspicuous part. Experiments on the 6th December, 1892. Weather, sleet, rain, and wind. Temperature on surface, dry bulb 42ao, wet bulb 40'. Pit shaft very wet, owing to No. of Experiment. melting snow, and had to scrape the timbers in shaft partly dry before commencing experiments. Note.-A small fan, worked by hand, had now been erected, forcing fresh air from the surface down 10-inch pipes to the bottom of the shaft, and returning upwards in the shaft. The additional ventilation thus secured had a remarkable effect on the later experiments. Present: Mr. Wardell, Her Majesty's Inspector; Professor Dixon, Mr. Kellett, Mr. Burrows, Mr. Bigg-Wither, Mr. Orsman, Mr. Mathews, Her Majesty's Inspector; Mr. Higson, Mr. House, Mr. Lea, Rev. Mr. Wickham. Weight of Gunpowder. Quantity of Dust. 1 1 lb. None 2 lbs. None 3 11 lb. 4 cwt. Hindley Green underground roads. Miss-fire. 11 lb. 1 cwt. Hindley Green underground roads. A violent explosion, with flame projected out of the mouth of the pit. The cannon was fired 1 minute after the last cwt. of dust was put down, and there was still some in suspension. l lb. 14 lb. 1 cwt. 50 lbs. Hindley Green N. E. road underground and White Moss mixed. A violent explosion, followed by volumes of flame rushing from the pit mouth. Used two firing cables, one with a bottle attached containing 1 lb. of gunpowder, and the other attached to the cannon. The bottle was placed on the pit bottom, and the cannon suspended five yards above it. All the dust was allowed to settle, the air in the pit being clear at the end of 15 minutes. Then the bottle was exploded, causing little or no disturbance in the pit; two minutes later the cannon was fired, with the result as above. This experiment was intended to represent the firing of two successive shots underground, and any dust in suspension at the instant the cannon was fired must have been raised by exploding the bottle; the cannon being suspended five yards up the shaft, was clear of any large accumulation of dust about the pit bottom. Description of Dust. Result and Remarks. No unusual violence or flame. These two shots were fired simply to show the amount of disturbance in the absence of dust. The result of this day's experiments proved that a very small quantity of dust in suspension in the air would, along with that at rest on the timbers, be sufficient- to bring about the conditions under which a colliery explosion might happen through the firing of a gunpowder shot. Erperiments on the 17th Januury, 1893. Weather, damp and thawing, improved as the day advanced. Temperature, dry bulb, 420, wet bulb 400. The shaft very wet, and the timbers had to be scraped partly dry before commencing experiments. Small fan at work. Present: Mr. Kellett, Mr. N. R. Griffith, Mr. Boole, Mr. Grundy, Her Majesty's Inspector; Mr. Mathews, Her Majesty's Inspector; Mr. Bigg-Wither, Mr. Orsman Mr. Lea, Mr. Clark, Mr. Jackson, and others. 73 APPENDICES. No. of Experinjent. Weight of Gunpowder. Quantity of Dust. 1 11 lb. None 2 1 lb. None 3 2 lbs. None 4 11 lb. 4 ewt. Description of Dust. - Result and Remarks. I Park Lane and White Moss mixed screens. 5 1ilb. No fresh dust put down. Same as in No. 4 experiment. 6 Roburite, 6 oz. 2 cwt. White Moss screens 7 Roburite, 8 oz. No fresh dust put down. 8 Gunpowder, 11)b. No fresh dust put down. The result of this last day's experiments proved more remarkable and conclusive than on any previous occasion. In three successive experiments the firing of a charge of 1'J lb. of gunpowder, aided by dust, lodged on the timbers in the shaft, and in the absence of any dust in suspension, caused what might fairly be termed violent colliery explosions. The decisive character of these latter experiments was no doubt due to the increased ventilation in the shaft through the operation of the small fan; in other words, the brisker the ventilation of a mine, the greater the danger from coal dust. This fact probably explains some of the explosions in the north of England, where the evidence pointed to their having originated in the main intake air-roads. It is also, I think, quite clear that the explosive character of coal dust depends more upon its mechanical condition as to dryness and fineness than upon its chemical composition. The various dusts used in the experiments were not subjected to any artificial treatment whatever, but were used just as collected; indeed, their condition as to dryness, as also that of the pit shaft, was undoubtedly much less favourable than that of dust lodged on the timbers and roadways of mines, where for months or years it has been subjected to an unvarying high temperature and a drying wind. With reference to the precautionary measures to be taken in the face of these facts, I have again to urge the total abolition of gunpowder from coal mines, and the substitution of certain " high explosives." In this inspection district all the more important firms have already discontinued the use of gunpowder. Any colliery in which the seams are naturally of a dry and dusty character cannot be successfully damped so as to render gunpowder safe. In making this report I wish to guard against conveying the impression that all colliery explosions are due to coal dust; no doubt many must be attributed to firedamp, but these are never so devastating and widespreading as those E 82480. No unusual violence or flame. These three shots were fired simply to show the amount of disturbance in the absence of dust. A violent explosion, and flame projected high into the air from the pit mouth. Two cwt. of this dust was put in to sop up the water in the shaft, and allowed to go to rest; then the remaining dust was put in, also allowed to go to rest. There was no dust in suspension at the end of 15 minutes, when the cannon was fired. Note.--This is the most remarkable experiment yet recorded, as there was actually no dust in suspension when the shot was fired, the whole of the mischief being due to the dust lodged on the timbers being disturbed by the shot. A violent explosion, and flame projected the same as in No. 4. This explosion was more severe than No. 4. There was no dust whatever in suspension, the mischief being entirely due to the unburnt dust of No. 4 experiment, which had again lodged on the timbers. No explosion of dust or flame. Roburite. The roburite was fired one minute after putting the dust down, and which was still in suspension. No explosion of dust or flame. Roburite. The roburite was fired 15 minutes after the dust of No. 6 experiment was put down. There was no dust in suspension. Violent explosion, with flame rushing from the mouth of the pit. The shot was fired 30 minutes after putting in the dust of No. 6 experiment, and there was no dust in suspension, the mischief being entirely due to the dust lodged on the timbers, which the shot disturbed and exploded. Note.-It must be noted that a gunpowder shot at once exploded the dust, after two roburite shots had been tried without success. The roburite shots were fired from iron tubes 2' 6" long, lightly tamped with coal dust. The tube was burst in each experiment. The cannon would not bear the shock of this explosive. in which coal dust is the explosive agent, for the good reason that in the latter case the dust is frequently co. extensive with the workings of the mine. Appended hereto are analyses of the air at the bottom of the pit immediately before an experiment, and of the gases in the pit the instant after an explosion of dust, also a statement of the hygrometrical condition of the atmosphere on the 17th January, and a careful measurement of the dust in suspension at the instant of firing the shots in the Some photographs are also sent earlier experiments. herewith. I am, Sir, Your obedient Servant, HENRY HALL. The Right Hon. H. H. Asquith, M.P., Secretary of State. ANALYSIS of AIR IN SHAFT immediately before an experiment. Nitrogen - 20"5 Oxygen 0"2 Carbon dioxide 100*0 No trace of carbon monoxide or Marsh gas found. W. J. ORSMAN. (Signed) ANALYSIS of the GASES in SHAFT during an Explosion. In order to get some idea of the condition of the air inside the pit during the explosion, samples of air were taken and were analysed. Two brass tubes were fastened to the rope that was used to lower the cannon, one 20 yards from the bottom, the other 40 yards from the bottom. These tubes were so arranged and constructed that the explosion, as it passed the tubes,. unsealed an outlet pipe, and the escaping water sucked in a sampie of air which was trapped by a special arrangement and kept in the tube until the rope could be wound up. By this method it was intended that the sample of gas taken should represent the state of the air whilst the flame was passing or directly afterwards. K 74 ROYAit COMMISSION ON EXPLOSIONS The tube nearest the bottom, as the analysis will show, did partly collect the gas in the above condition. The tube at the top, however, commenced to act prematurely, and was probably started by the sound wave which preceded the explosion. This tube simply contained ordinary air. The following is an analysis of the gases found in the lowest tube : 3*9 per cent. Oxygen 75"9 ,, --Nitrogen ,, 12*1 Carbon dioxide ,, 81 Carbon monoxide As will be seen, carbon monoxide was formed in some quantity, showing the presence of a large excess oqf coal aust. This latter fact was further proved by the presence of large volumes of coal dust in the flame at the mouth of the pit. 100"0 The presence of the above quantity of oxygen is probably due to the apparatus starting woriking before the flame got. to it. Dry. Hygrometer. The above experiment was the first successful attempt to get samples of gas during the progress of explosion, and any further remarks and deductions had better be postponed until further experiments cawbe made. WM. Ts. ORSMAN, F.I.C., F.C.S. DEAR SIR, % 18th January, 1893. THE following are the values of the hygrometer readings taken on Tuesday, .at the White Moss Colliery, Skelmersdale, by Mr. Matthews:- aturation S00. Grains of Vapour in a Cubic Foot of the Air. Grains of Vapour required to saturate a Cubic Foot of the Air. Temperature of. Dew Point. Humidity. 42 At beginning At end of experiments Wet. FROM COAL DUST IN "MINES: - - 40 37" 5 85 2" 6 0'5. This addition would produce saturation. 38 36 33*3 83 2*2 05 The above shows that at the beginning of the experiments the quantity of vapour in the air, in the neighbourhood of the hygrometer, was 85 per cent. of the total quantity required to saturate it, at that temperature; and at the end of the experiments, 83 per cent. Y ours obediently, Henry Hall, Esq., JAMES "GRUNDY. H.M. Inspector of Mines. MEASUREMENT of DUST in SUSPENSION in the SHAFT during the earlier EXPERIMENTS. Two hundredweights of dust were put into the shaft, and at the instant a sl2t would have been fired, a box with a superficial area of one foot was lowered to the bottom of the shaft and allowed to remain there until the dust had entirely settled and the air was clear, the box was then drawn up and the dust lodged upon it weighed. It had collected rather under two ounces, which would represent the dust suspended in a column 50 yards long, with one foot superficial base, or, taking the whole capacity of the shaft, the total amount would be rather less than five pounds. H. H. -- I C ---- I-C--------Y --- THE ROYAL COMMISSION j FROM COAL DUST ON EXPLOSIONS IN MINES. Photograph,to dlustrate FMr Heny Halls Report (rpenia &ITX) WYMAN ANo S9NS E' 3 4vts. M36trtorrvHieryd~t at rest25 mzntes, Grzio vderdedmf C an'lfn'lnise K Huitn dean. LIT. LoIoon 6313.794 THE ROYAL COMMISSION ON FROM COAL DUST IN EXPLOSIONS MINES. Photograpk to ilhastrateMr Henry Hal s Report /Appendicl§.) WYMun Julys 1893. AND SONS LT LITH LON DON 6313.794, 5preadinTg famne 60(-el- e Eppletn elihry,3 Main Calda/ztA t -zruer-groundtimba er(ed Myyanpiowder4minuntr at/rputtanydast dewMn / THE ROYAL COMMISSION FROM COAL DUST Photograph, illustrate to ON EXPLOSiONS IN MINES. . Henry HalW Report pp ndIX.) WYmANAND SoNs July ? AS193. .LITH LONDON 6313.7.9 Fk7rmnc6Wfat Jminate aS r puntting dovwt Bemnzw k Bar-Dtyzht. 2 cwwned , iied, Wbs.gupowderfiontCannmnw tarmped with Cal-d st'. . t THE ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES. Photograph to illustrate Mr. HeLy IIal's Report ;'---~~: (Appenxhwc XIX.,) WYMAN AND SONsL LIH JuTrzly & Y9,3 Af93 ( ~ LiTm. LONo G313.7 94. .Fkmwd9t glb un zpcwder tfi7d tree minutts Buslyeamn . / Beamih Clliery, afterdustwa.put down, fired imn Cannon., tamped wtk 'Z7ay. Air# KKETCH OF" SHAFT I-® Wyman &Sons,L,L th,63,Ca rter Lane, ?794. 63/3, 75 APPENDICES. APPENDIX XIX. Rainhill, Prescot, SIR, 20th August, 1893. ON the 29th March last your Commissioners addressed a letter to the Secretary of State suggesting that I should undertake a further series of coal dust experiments to include dusts collected from the principal seams in the respective mining districts, each separate dust to be tested as to its inflammability in the same way as had already been done with certain Lancashire dusts. I now have the honour to report as to the method adopted to carry out this work and the result of the experiments. In order to keep the experiments within practicable bounds, and at the same time to ensure their being sufficiently extensive and inclusive to be decisive of the characteristics of the dusts which accumulate in and about the roadways in mines in the various coalfields of the kingdom, it was necessary to fix a limit to the number of samples to lie tested, and with that object the following code of instructions was drawn up for the guidance of the gentlemen connected with the mines who were kind enough, at the request of the respective inspectors of mines, to undertake the collection of the samples:-" The dust selected should be that found lodged on the timbering or on ledges underground, or on ledges above the screens on the surface. The dust should be gathered with the hands and not by shovel, and should be put in bags containing about a hundredweight. Each separate bag should be placed in a deal box tongued and grooved, and placed in some dry place and at least as warm as the spot where it was collected from. The boiler house or dry storehouse is suitable. "There'must be at least 5 cwts. of any particular variety of dust collected and forwarded, to ensure a fair test of its liability to explosion. "It is impracticable to test more than four samples from any inspection district, consisting of about 5 cwts. of each variety. " It is imperative that the dust be fine and dry, and it is suggested that one of the samples should be from the seam of the district which bears the character of being most liable to colliery explosions, and one from the seam considered most safe. Each box should bear a small label in addition to the address label, giving the following particulars :-Weight of dust in cwts. and lbs., name of seam of coal, name of colliery, quality of coal, where and by what means collected, whether from underground or from screens. "The boxes containing the bags of dust should be forwarded by rail or a covered waggon, and each box should be labelled on the outside as follows :-' Experimental 'coal dust. To be kept dry and immediate delivery. ' To Messrs. The White Moss Colliery Company, Limited, ' Skelmersdale, Ormskirk.' " The samples of dust were all received in excellent order, some having been gathered from the ledges and timbers underground, others from the underground roads and others again from the timbers over the screens on the surface. In a few cases the dust had been passed through a fine riddle, but there were enough samples in what may be called its raw state from underground roads to ensure that the result of the experiments did not depend on any unusual or artificial conditions. Whatever care and labourmay be bestowed on the collection of samples underground, it is, I think, impossible that the sample would be as fine and dry as that floated in the ventilation of a mine and lodged on the timbers about the roof and on all uneven or projecting surfaces of underground roads, and which latter dust is always ready to be lifted and thrown into the air current by any violent rush of air such as might occur through a blasting shot blowing out or in consequence of the ignition of a small body of firedamp. The samples received for experimental purposes numbered in all 52, coming from 45 different collieries and from 36 separate seams, and with the exception of four or five samples all were tested. An apology is due to the senders of the samples which had to be left over, viz.:East Hetton, Littleburn, New Seaham, Cannock Chase, and Messrs. Pope and Pearson. Several of the gentlemen who sent dust have been present and witnessed some of the experiments. The mine shaft, placed at my disposal by the proprietors of White Moss Colliery, Skeimersdale, is the same shaft in which I have made manyprevious and similar experiments, the results of which have already been brought under your notice. It is 50 yards deep, 7 feet diameter; struts of timber 6 feet long and 7 inches broad are fixed from top to bottom of the shaft at intervals of 6 feet to represent the timbering on an underground roadway. (See Plan of Shaft appended.) The ventilation of the shaft is secured by means of a small fan on the surface driven by hand, and forcing fresh air to the bottom of the shaft through 10-inch iron tubes. These tubes reach to within 5 feet of the bottom of the shaft, and the quantity of air passed is about 750 cubic feet per minute. (Result of analysis of air accompanies Report.) A wrought-iron cannon was used for the gunpowder shots. It measures 2 feet 11 inches in length with a borehole 2 inches in diameter and 2 feet deep, and it was charged in every case with 1I lbs. of ordinary blasting gunpowder tamped lightly with coal dust. The tamping occupied a space of about 12 inches. The cannon was always charged on the surface, and lowered by means of a rope to the bottom of the shaft and fired in an upright position near the centre of the shaft by means of a detonator in connexion with an electrical firing machine. The amount of charge of gunpowder used in the experiment, viz., 1I lbs., was fixed upon as being likely to develop a similar flame to that produced by the accidental ignition of a small quantity of fire-damp in a mine. This charge is somewhat heavier than an average mine shot, but in consequence of the tamping being placed loosely upon the explosive and not rammed home, the shock and violence of the explosion is very inconsiderable as compared with an average mine shot, where the tamping is always rammed home and beaten solid. Mine shots in this inspection district and used in strong coal amount to as much as 20 ounces or even more, and by reference to the earliest series of these experiments submitted to the Secretary of State (1890), it will be seen that coal-dust explosions resulted from the firing of charges of one pound of gunpowder. The experiments were commenced on each day by firing two pound charges of gunpowder without dust, so that the onlookers might be better able to judge of the part played by dust in the subsequent experiments. When a " high explosive " was used it was fired from an iron tube tamped with coal dust, as it was feared the cannon would not bear the shock. In a few cases, in order to make the tests of gunpowder and the high explosives precisely the same, the gunpowder charge was fired from an iron tube exactly similar to that used for the high explosive, and in two or three cases it will be noticed that the cannon was tamped with clay in place of coal dust. The conditions under which each sample was tested were kept as nearly as possible the same in every case. Usually the sample was first tested in suspension, that is, the shot was fired with some of the dust floating in the air in the shaft; this state of things was considered most favourable to an explosion of the dust. If this experiment resulted in an explosion then the same sample was again tested at rest, that is, an interval of 15 or 20 minutes was allowed to elapse after putting the dust down and before firing the shot, the dust having by that time settled, part on the timbers and the remainder at the bottom of the shaft, and if an explosion resulted under these conditions, the tests of that particular sample were considered complete. I found by a careful collection and weighing of the dust resting on the timbers after putting down 2 cwts., that these timbers afforded a lodgment for about 80 pounds of dust, and I am of opinion that this portion only of the 2 cwts. put down was exploded and gave rise to the whole of the phenomena exhibited by the explosions. When the testing of a sample was complete, one or two what may be called " blank shots" were fired in the shaft to blow out any remnants of dust before the testing of a new sample was commenced. The experiments occupied 12 days, the weather throughout being most favourable, and on several days there was an unusual difference between the wet and dry thermometers showing the atmosphere to be very dry. (See accompanying description of the weather.) In the list of experiments which follow, the tests for each county are collected together in preference to giving thie details in the consecutive order of the experiments themselves. I K2 ~EtOYAL CO~liMISSION 76 1~SPT~OS FItO~ri COAI, DUST IN MINES : IONS Co 0 0 0 Co 4-Z 0 0 P4 blD -4 0 '5) rl0 o 4( 04 14l .5 oo 05r O 0 S O 05 U) C1 (+ 0400 0 4 -4 0 0 .,) +.5 0 0 6 w) U) . 05W C) 3 0 • , 0 @ , ,- U5 0 0*l)i 0 6' 0 40 r 0C 000 0 P4 C) CA .504 rd 0 -o 0040 0040 cd Q.) 0 +4C)4-4 42'C)C) i 0 0 co 0 P4 q 0 I I P-4 CAD 0 OD 4 rj l r0 m ;> 0+ "'='0 0) 00to *qi) C> 0 0) o - 0 0 r.4 o P- 0 GO W 0' 00 z0l. F I U) IZ: I ©~ r- ~ Iz i=4-+-') 4 P cO -I 4-1 lil -+. C I rI rI 1 0 o0 P 1 &4 r-4 0 ru4 - I C0 r- 0 - 44 0 --14 N 0I * rd40 -40 Nc -4c~ r rd 0I C0 01 Cd rd C -4C 0 Pi0 CH I I 0 C6 0 CD I '04 ~0 6 0 6 6 0 ~ i1 i4( i I N0 i 0l - 0 44. 0I C) -~ I .. I -c0 0) C)J I I COa CC C) d I IPPENDOJVS. 17 4-41 1.4 . 0 r .0 fri .5 -I) .0 0 .0 0 0 r00 0 0 0 ;10 '.0 .0 '141o 0. 04 004 .0 0)0) P014 ~4 CP 0) 44 P44 .0D rd0 0 .0 14- 0024 14- 1)4 4C 0r0 r.0 4a .0- -4 H050 ad4as bO .0 to bi) bd .00o - -11o .4 93 'N i 1.n 14 0 0 0 .00 0 - .0 1,1 S 010~ 0 C.0)4 0 P-4 -~0 0 21. 0 .- 65 g.0 0)* . ~C)) 4 1 0 0 0 ~0 6 4 o~ 0z 4Qz -4-41 4--l r0 p k.4.. 14.0 6544 ,0*~ cd 0 .1*A- 0 P4 ~ ~ ~414 1 . C3 *-4.4 0 ;t4 -4 o 0 C) -r-4 r-4.00 0 0 5 o-o - .4. . 0 00 -4-a 0) co 0 CO co 10 cq 0 . ~ .0.I 0 0I 0 0 0 ,4 0-)..q 0 0 1 Coi 0 CD r-4 6 0 0 .0 .. r40 . 0 .0 100 0 0 00 o I' 0 .0 0 I 0 0 ).0 0 I .0 144 -4.3) 0)0P41 ) 00-r- 0 r" -i I $ -4 )P4) )0 P- r4 -4-q rid'. .0l rd 1f 0) 4-D .0 4-1 .)-4 0C. C. 0 Cl 00 rd ;-4 .0-q 0 D d d 0 .0 u0k d dQ1)0 nrd0 )L0 ;-0r d rd .0 rd ) .,-1000 I19. . 0 cd;- ., 4T4 PR I 0. .0 1 -till. .0Ct2 4-; q C a 0L CL. ' )I 1 '. 78 ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES: 0 0 U) 0C 4Q1 0 0 0 ri)~ C) ~rS 4-4 CA 4-.) P . ~04U 45)~ 0.~~ r P., CC ) U a) 4-a ~C 0 zS C Cd 0 0 c s2C3 ce 00.2ND 00 c )2o 0fr""' 4. 0 4 cd P40 o ro 0 0 o 0 U c 0 'o- CQ ) 4 0 00 ) U U SS - 0 r- 0 cq U UCu12 - * &tco)0 0 ) o rUU)U0 p4 0 0 - o 05 .- -2-4 4 ^b 0C0) co ~ ~o UGU 4: 0 U 00 A 19.: ra r--U ; P- -P- C)'-C)-Cr -N 0 a 414 icq C IPIC$ F I:: U)PC 10.U~c P-PU 0 0 a) 4- 4-P-aI a) D t0 rd PU 0 0U.0 rr-4 00 Cd ~ ~U) C~ 5 .- ~ o o ~C) C) 0 S P4 W 00 .5 6 6 6 6 Cd C) ~ i I . * *~ I 0 0 0 C) P4 79 APPENDICES. 0C 0 r-) *'C0 btj 4 b0 P-4C rn Cd 0 C 0-0 0 0 c ~4 C)CC4 1 (1) ;4 ~ C- o a 5 a - ~ O a ,,0aCC 8 a~ o 4i>.~.j a~ aflO 00C C04 ~ C)j) CC'040 P1 0C ~ ) C).~r-4 P-4C+40 - 4 0 P.4 0 04a ~ Z0 0o Z 0 0 40.4 0 z'4 0 . 4 ~ 04 C-4 000--,0o 0 -4- 0 & 0 P- ' +' 041 0 U) P48 00 CO C 04 C C 0 CCC/ . 0 0 0 U) U 0 0 0 w)U2 &0 U) U 14C)0) 4) a) 46CC 4 C) CV) C)0) CC U) -t4U)-el140.-14 C C +aW4 U) 14 ) U I 0 4 --- - P4 0j 0 00 Piz~ P4~ 00 ---II C) C) 0C ~ cCIv C) 00 o ~4Z - 01 C) 01 0 0 Z ~A C) 01 C) 01 .~ C) 0~) 4") Ea * 4- 0 ~6 '~ ~C) CCU4 Q -~001 6 ~ 0 6o ~ - 6 6 0 C) 0 0 o o 0 0 6 ~ 0 0 C 0 I &aa P-4I I S C 0. a I I I C) o 14CC CC*~CC f I 6 6 66 4 6 66 6 6 I ~CC~ I ~ 6 P-4 04 4. 4 01 CO ~4~) 5 C) ~ 0 K4 80 ROYAL COMMISSION ON EXPLOSIONS FROM COAIL DUST IN MINES: 0 0 o 0 °,.. (E-4 rd 00 000 0 8 . ar 0p 0 d " w 1 rd 0W 1 0 0 r04. 0, 11 0 F cd r--4 cd P -4 0 Q P 0 4-3 4 4---' 0 o-o P -0 r-0P4 0C- a) :o - 0> 0" Cul Ce( rd bD P4 0 . W! rs 0 .8 o0 . .I-9 0 o0 r- 0 .C" c r-4 o w ~ a .,. 00 Vo 0 :.0 P-4 r d 4.) P4 4- = P 00 0 0 0 CIO 0 o CI) m4 C 4 ocC 4,,)0 04 .- r . 0 0 0 - g o m~ 4a 40 0 W P4Q 0 00 0 = al~ I) c 0 w 4-; - . .. 'p- 0 0 0 r-4 I 9 rd0d 46 0 00 I C I o I a Ir I I r4 8A, O 8 8' o I1 r-4 0 8 0 4)2 4 8. W 44 ; hli d 4.2 P.40 Bcr 0e 00 ~ r EP rd 6 P44 0 I .Cia 66 g I I, 0 A PPENDICES~. CC) . ft 1 '00CnCC 04_ ouq P- 0 0) U) 00 C) "" 00) P4)C 00CI 4-4 0 0 0C C Q)-C 00 Q.) r--4 C)0 0 0 C 00 CCd C c ;-4 'C)oC N0 0 oo) U), C CIS Cs 00 CCd CC 0 N>1 a-P4 ,OC CC P4o C) C) 6W~ 'a~ TC a-a CU 0 cC Cd C) ad C)- CC 0 .CC C C 0X C) U) 0 0Cd $Z0 CC 0 0 CC-a C 0 b 6- N ;-4 C C) 0 z .d NOCC m SbCC 0 0 U)0o 0100 z z 0 0 CO C.) 01 CoD C 1 l 0 ' ;-4 0 0 P4 *0U 0 C a 0 CC CCCC 0 U) W) a U) 0 U) U)U) CC CC CC CCC 0 CC 0P00 4 U CCCCU2 U U)4-a I -'Cl P4; 'CC P-4 6.6 .6 ~ CCCC M- I # ~ .6 .0 P--4 -a I '-al-a '-l- r-4,C '4-a.~ 164.6 r-10 -4U-~ ard C) C) 490CC IC) . k) -4 +aCtLa -0 U -. 9C~- U)I 0 C0 0 a-a0 rdQ Cd~ C4-4 0 0 0 4 C) QC 4Q1 6 '~6 .A. 00 ~ , 6 1 a-- 1-4C Z4 0; a 0 0. rad pq 'C) 6 ~CU 'CC ~ a-aCC 0 o ~ C) 0 a a ~C) cb 4 6 C) CCC ~ 0 6 '-a-' I E 82480. a a 6 CC CC 0 6 q ~ CC H 6 01 CC C) CC 6 ~ a 66 4-a, 'CC C) 'C) a C) CC~ 0 'C 0) Co .CaC 6 ~-a-a6 ~ CC 0 ~ 0 L 82 ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUJST IN' MINES: 4 r-14C &n bo 0 CC C)C) C C) c)2C C r) 0 C 04 C) 4.) 1-4 ~ r- C CC) En I0 PI c'sd C) NbiD 0 0 cdCO z b5 bo bJ 00.50. r-4 - P4 0 z V- 0N 4z P4 4 0 C)) 0 - APPENDICES4. 0) 00 P. Cd0 &0 0)0 0 ,,_c 4-D Q.) '0) U)).d Cd ;44 U P44 bD In P)0) .Go0) 0044 4 000 0)) 0 0 4) 4-a 4)00 P-40 ) 0 0 0 P- 0) 0)40 o t4 r IC oC)0 co ~CO 0 mC k)~ - ko r-4 0 - &fo iM6 0 00 0 0 C 0O 0 0 P4 P4 z4 P4 ) 4.2 a) P4I ) . a) U)C) 0)0 0)0) -0r 6 0) 0) 0 -) 0 .0) ~)IC4 - 00 ~ 0)04)0,0 ~ P , - - d) -4 0) 0 0)4 0 6O 6 C) C) C) (1) (0) 04 op 000) C4- z-))4 CO 0 bo0 0)14 00 0 10 0,) P-4 4.5: 0L 0)0 0 - 84 ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES : cz 7"N o 0+ - i. 0)0 (@0 0 ) ,. ~ - 0 ?" (L) .4 0r 0) 7 0 °d 0 N 02 ;4 ErO 00) d .4 m" 0 @05 cd (O 0) to e 0 , O I4 0 )@0 Q0-42 o -q) ao @E P0 00 ~ o .5 0) CD @0 • " 00 Pc ~ D ; 0 )0 (0 W) Ad @2 j CD0 ;- oo - " r-4 r r-4 0 0 0) 0 ,, to O a) o 0 o S r-4@0 00 E-40 @0@ 00 0 e - 02 P4 4- zQ P4 I . I.--_ -4 _ -.. I - - - 42&0 a . a ,,C 4-; 0 @00 *4 4 0 -4 0 U) 0 Ofr ;@N rO n LI N1) 0 00C3 0) .o 00. S c 0040 bI) -4 r) ) i . C) .,4 'C 4) '41 ~ C) 0 0 0 0 0 0 U4 P0 w202 0 00 *@) @f 0 0 0 o 0 N P, 0 0 C) 0W ! 00 co Coa@C0 co 03 00 @2@2 P4 -4@Li c 0 P4 02 0 0 P404ae C _0 4 02 -~ 4.4Ic 0 0 04 4-) am P @2i @2 @ @0@0~ U @0 @ rt: o F P44 F P a I 0 r- -. 0 ! 0 0 0C)00 Co aa a o a01 - on Ga rd @ 0 0)0 @2 IT 0 P4 0 0 i ! i- 000 000 zz 0 00 Co 0 r4 0 - o Co 4-Do-@m @0 0@ cn o" 4z-az C. @2 o 0 @ 0 "ti bO c rdII~ .a e k -0 04 zz o ce @22 aC) 0 @0 C rd rd a .oP4-r ao0 rn -42 S 04 b c0 1 U@ 0020 W) @0 ) o ---------- I rd d a d C) o01 66 P 4,P a 0) a 0 z C F 4 ., Y I 6 IcC 6 I 0)B a 4)3E d 0) (ar 4 Z0 0 a 2-4 d rd 0 Q@ '@00 5 rd 4 Ca 00) 'a d d *0 +~ 0) @2 WC)C) rd .0 0W a- ~ cC) 0 a a a @0 0 a a B @O 0 ao aa C)~ Ctc 0 C o cd I---~---- 0 Ap a ~ " ^0) 0) '@ A 0) 0 od 0.0@z 0 A a OApo a, a a a a a a a r- 66 01 @0 . 0 4 a~~~~- 1 a zi -ICIS @2 6 Z -80 0 r dc d Q, 0" a ~60) 6rd6 0O.4 12~l @0 a a amR @0 e co~ k a oo @2 d 00 00 0) d A l APPENDICES. 85 ___ 0 0 0 4'a C)C) 0 0 CC k -4 C) CC 0) V.j !) 4-j 1410 S .C) -4 CC C 0 r-- 0.0 ,,U) N 0-N = 0 0 U)0 CD S 0 C o Oo r---4 C)j c rdd S0 ~r q 4-j b 0 0 0 00 0 0 0 0 4-1 rn 1/0rd0. C) 0o .)o CJ2 CI) mi0 Hr5 m ,4 0 d 0 rd . .. 0 I. 0 z P4F C) 0D CI ¢l) o b 0 OC B C bf 4 C4- rd; .) 0 0 C 6 ( C 0 I1ci 6 0 0 . 5ca -4 4-D Zc 1 2 6 0 4-4 c4CC 0-4Z, d H0 Ur 6 66fr- 0 L3 86 ROYAL COMMISSION o. ON EXPLOSIONS FROM COAL DUST ' '• - IN MINES: > m "- oo .0 .F. 4 4rn o -4 70, (19 P-4 44 5"4).roo..0 W 00o>. 4-24) ;4 ;4 w rA 00 ... 000 0 0 40 4) or00 -4-a0t-4 0 4)) 0 *r04'4 0 04 U 4,0 004 0 _ _-4.2,- 40 _ 0 rd 40 04) _ _ 4) 14() :o P"- $ _ 1, 1 _ 0 _4,z0 A 0 '4 0- 0-Pbn 0 t) :, r ~+40404 4 .5 i 0 P-4 S fr)' C ~ ~d N 4) 0'4 *- W) 4) -q ca~ •1 0 4 .z 0.C 4-a (3) ril 0 $ 0 P4 040 C' a' o0 ~ 40=-6a0P4 4 P.; ; 0 4) ) 0 4) ) ,)' 4 , -" 4)0-D 4. I 9.4 i9i4 - rd- d 3 S I U, P4 P44 ; 'd -41V I - '4 '4 , l '4 44 4- I r-qr.q+ a 4) ; I 4 0. ' , '.4'4-;44j-CD I P-0 rd 4) 4 '-0b d-dd P-4WCd ,=,' rd 4 0 4 .4 '4 '4 - :2 w 04 -. S I -4)4V, I1 d 'di 00'0 0 0 0 044 rd0 r$ 0rd t cd rd 0 ZJ al l 0o p * Cd 14 Cd S 4 04- 0 0' a 6 0 P; C+-q 44r +4 00 01 o o-.ll I 0 rd 00. c0a00 44 4.4 i .'4. (v cd0 c0.-a0 Cd -4 p 0 k k rd A b M i 4) 0 '4) * 0:= 4) 0 0 c 0 4-)l 4=) 0 )-Z ,, 87 APPENDICES. The phenomena presented by these experiments as they progressed, and a careful examination of the detailed results warrant the following conclusions:(1.) That the flame from a blowing-out gunpowder shot in the presence of dry coal dust always ignites more or less of such dust, and so increases the burning and charring effects of the shot. This is proved by the fact that in almost every experiment which did not result in an actual explosion of dust, there was nevertheless severe charring of the electric firing cable for several yards up the shaft, whilst without dust and with a similar charge of explosive, no such charring occurred. (2.) That when a large flame, such as that of a blowingout gunpowder shot, or the flame from the ignition of a small quantity of firedamp traverses an atmosphere containing a very moderate quantity of dry coal dust, the dusty atmosphere will explode with great violence, and the explosion will continue on and pass throughout any length of such atmosphere, its violence and force increasing as it progresses. This is proved by the fact that in nearly every case where the cannon was fired whilst there was dust suspended in the atmosphere of the shaft, a violent explosion followed, the force of which was evidently only beginning to be developed as it reached the top of the shaft and escaped, spending itself in the outside air, the flame in some cases attaining a height of 70 feet over the top of the shaft. It is true there were exceptions to this rule, as in the case of the samples received from the Forest of Dean, Somerset, South Stafford (Great Fenton and West Cannock), Moston, Lancashire, and South Wales Anthracite. The difference in the results from these dusts was I think due to some difference in the character of the coal seams in those districts. There were also partial failures with the samples from Auckland Park and Trimdon Grange (Durham), and from Talk-o'-th'-Hill, Astley and Tyldesley, and Llanerch, but in these latter cases I am satisfied that a little more perseverance with the tests and a more careful collection of the samples would have resulted in explosions.* (3.) That coal dust from several seams in different districts, notably those from Glamorgan, Monmouth, Durham, Lancashire, Yorkshire, and Scotland, are almost as sensitive to explosion as gunpowder itself. (See details of experiments where violent explosions were produced with the dust at rest in the shaft.) (4.) That coal dust is as a rule more sensitive to explosion in proportion to its high quality and freedom from impurities. (5.) That a ready supply of oxygen such as is supplied by a brisk ventilation has the effect of making coal dust explosions more probable and more severe. (6.) That certain "high explosives" are iicapable of igniting or exploding coal dust. It will be noticed in the details of experiments that charges of Roburite, and, in two or three cases, Ammonite were fired without effect, but as soon as gunpowder was introduced, its explosion was followed by violent dust explosions. The difference in the behaviour of gunpowder as compared with the " high explo§ives" was most impressive and convincing. Of.the whole of the dusts tested, that from the Albion Colliery, Glamorgan (Aberdare or Merthyr Four-feet Seam or Upper Four-feet) excelled all others in violence and sensitiveness to explosion, and this seam in the South Wales district has the worst history of any in the kingdom, upwards of 1,600 persons having been killed in it by explosions since the year 1845. Indeed, throughout the experiments, one could not fail to be struck by the great violence and sensitiveness to explosion exhibited by the samples received from collieries with an unfortunate history as regards explosions. It was, I think, also evident from the experiments that the higher the quality of the coal seam the more liabihlity there is to explosions of dust, and it is singular that the collected history of explosions in mines in past years shows * In the Haydock experiments reported in 1890, the dust explosions travelled 200 yards and were evidently increasing in force and violence as they reached the top of the shaft. Royal Commission on Explosions from Coal Dust in Mines. that nearly all sweeping disastrous explosions have happened in seams producing the highest class of coal, such as the Durham Hutton Seam, Yorkshire, Barnsley and Silkstone Seams, the Lancashire Arley Seam, and the South Wales Aberdare Four-feet and Black Veins. With regard to precautionary measures to be taken in the face of these facts, I have again to urge the total abolition of gunpowder from coal mines and the substitu- tion of certain "high exulosives." Many of the largest firms in the country have already of their own motion taken this step. Mines which are naturally of a dry and dusty character cannot be artificially damped so as to render gunpowder safe, but it is nevertheless imperative, in the absence of gunpowder, that every possible effort should be made, either by watering or removing, to avoid accumulations of dry dust, so that any accidental ignition of firedamp may be limited in its effects and prevented from developing into a sweeping explosion through the agency of dust. During the last twenty years an average cf twenty persons per annum, or a total of,400 lives, have been sacrificed in the handling alone of gunpowder cartridges, that is, through accidental ignitions by stemming, drilling out, or setting it alight by candle sparks, quite apart from the part it has played in nearly all great colliery explosions. The loss of life from explosions during the past twenty years amounts to 4,098, and it will be much below the mark to say that gunpowder is accountable for 50 per cent. of these explosions, or a total death roll of 2,449 persons. It is deserving of consideration and experiment to test whether a coal dust explosion would be stopped in its course by a certain length of roadway being constantly kept in a wet condition. Personally, I think such a plan would not prove effective in consequence of what may be termed the pioneering cloud of dust which precedes the flame, and also in consequence of the great explosive force developed by a coal dust explosion. In three or four experiments the remnants of dust left in the shaft after an explosion proved sufficient to cause a second explosion. Below will be found analyses of the air in the experimental shaft, and of certain samples of the dust used in the experiments; also a description of the weather on each day when the experiments were proceeding, an I also some photographs of the dust explosions. I am glad to be able to report that the experiments were completed without accident or injury to anyone. I am, Sir, Your obedient servant, HENRY HA LL. The Right Hon. Joseph Chamberlain, M.P. The following are analyses of five samples of the experime ntal dusts:Volatile. Lightmoor Colliery Clifton Hall Colliery Albion Colliery Barwood Colliery Beamish Colliery - - - - - Coke. Ash, Rocky seam, from underground Trencherbone, from screens - - 22 8 20*8 30 4 68*4 46* 8 10*8 4 feet seam, from underground Kilsyth seam, from underground Busty seam, from screens - - 14 1 24 7 28*3 80*4 45 -7 67 3 5.5 29"6 4*4 - W. J. ORsMAN. (Signed) NOTE.-The dusts from underground roads contain a good deal of shale dust; hence the large quantity of ash.-H. H. The following are analyses of the ventilation of the shaft taken during the progress of the experiments :Oxygen Nitrogen Carbon dioxide Sulphur dioxide - - - - - - - - - - - - - - - 20"56 79"20 015 0"09 100'00 Nitrogen . Oxygen Carbon dioxide - . - - 79.3 . - - - 20"5 0"2 10010 No trace of carbon monoxide or marsh gas found. (Signed) W. J. ORSMAN, L4 88 ROYAL COMMISSION NATIONAL ASSOCIATION OF COLLIERY LANCASHIRE BRANCH. ON EXPLOSIONS MANAGERS, Orrell Colliery, Wigan, Aug. 10, 1893. AT a special meeting of the colliery managers of the above branch the following resolution was proposed by Mr. Halliwell, of Dewsbury Park Colliery, and seconded by Mr. Walls, of Hindley Field Colliery, and carried unanimously:"That the best thanks of the Lancashire colliery managers be tendered to Mr. Hall, Her Majesty's Inspector of Mines, for his kindness in inviting them to witness his experiments with coal dust at White Moss." As secretary of the branch I was also instructed to say that every colliery manager who saw the experiments is now firmly convinced that it is dangerous to use gunpowder in a dry and dusty mine, and that it ought not to be allowed to be taken into such mines. They are further of opinion that no colliery manager would continue to use it if he once witnessed your experiments. Yours respectfully, On behalf of the colliery managers, (Signed) P. ME HERS, Hon. Sec. To Henry Hall, Esq., H.M. Inspector of Mines. Hetton Mr. Bell, H.M. Inspector, writes:Hutton "There was an explosion in this pit in 1862. Said to Seam. have been in the boiler flues. But it is a curious coincidence that a powder shot was fired at the same moment on the engine plane; the hole is to be seen to this day, and we must conclude it was a blown-out shot. "There has been no explosion at Hetton Colliery since this date. (Lamps used throughout.) " I have heard of an explosion at Eppleton, even before Eppleton Main Coal. the days of Government inspection. I think it was in the Hutton seam, and either the late Mr. T. E. Forster or Mr. E. F. Boyd would be the viewer. There has been none since. Lamps used throughout. Elemore "An explosion took place in a stone drift near the shaft Low Main. in 1886, when 28 lives were lost. You will find a full account of this explosion in my report for that year. This pit is now standing, and we could get no dust from it. Lamps used. Beamish. "Both in the Newcastle district. Busty. Usworth. Maudlin. "This is a dry and dusty pit, makes a considerable Silksworth Colliery. amount of gas, but they have had no explosions. Lamps used. "This is also a dry and dusty pit, making part gas, but Auckland Park, Har- they have never had an explosion. Lamps used. "This pit is not what you would call a very dry pit; it Brancepeth 5/4 or Jet. makes no gas, and they have never had an explosion; but in April 1889 an explosion of dust took place in a large coal hopper at bank, by which three persons lost their lives. A full account of this is given in my report for that year. Candles used in whole, but lamps in brokens. . "Very dry and dusty, but no explosions are recorded. Murton Hetton. Lamps used. "This is a dry and dusty pit; makes part gas, working Trimdon Grange, long wall, using lamps, shot firing in face. Exploded in Harvey. February 1882, killing 74 people. See my report for that SIR,. Seaham Colliery, Hutton. No previous explosions. No shot firing since exyear. plosion in 1882. "Dry and very dusty. Exploded in October 1871, killing 26 persons. Again in September 1880, killing 164 persons. Both explosions occurred during the firing of a shot in stone drift near to shaft, and, curious enough, both shots fired in the same refuge hole while attempting to enlarge it." Mr. W. N. Atkinson, H.M. Inspector, writes "" The following samples of coal dust were sent to Skelmersdaie from North Staffordshire :Great Row Seam from Great Fenton Colliery. Seven Feet Banbury from Leycett Colliery. Cockshead from Whitfield Colliery. Bullhurst from Talk o' th' Hill. "With reference to the character of these seams as to explosions and -loss of life, nearly all the chief explosions have occurred in the three latter, and no serious explosion in the Great Row. "I cannot give any particulars about the small explosions, of which there have been a great number in the district, because Mr. Wynne's reports rarely state the seams where they occurred. No explosion is recorded as occurring in the Great Row seam, but it is probable there may have been some small ones. It is one of the upper seams, and has not been much worked at such depth as to be dusty. FROM COAL DUST IN MINES: "The 7-ft. Banbury, Cockshead (called Cockshead on the east, and 8-ft. Banbury on the west of district) and Bullhurst are amongst the lowest seams worked, and when at depth are usually both grassy and dusty. All the seams vary greatly as to gas and dust according as they are near the outcrop or at great depth. "The following is a list of the chief explosions which have occurred in these seams during the past 20 years. In the 7-ft. Banbury. Jammage Colliery Silverdale Colliery Leycett Colliery ,, ,, - 1876 1879 1880 - 5 killed. - 5 - 8 - 62 ,, ,9 ,, In the 8-ft. Banbury or Cockshead. 1873 1875 1878 - 1889 Talk o' th' Hill Colliery Banker's Hill Colliery Apedale Colliery Silverdale Colliery Whitfield Colliery Lillydale Colliery Mossfield Colliery - - Bignall Hill Colliery Leycett Colliery Apedale Colliery - - 18 killed. - 43 , -. 23 - 3 - 25 - 8 - 64 In the Bullhurst Seam. 1874 1883 1891 - - 17 killed. - 6 - 10 Mr. Martin, H.M. Inspector, writes:"In reply to your inquiry as to the histories of Celynen, Llanerch, Radstock, and Lightmoor Collieries in respect to explosions, &c. " Raises about 15 to 1,800 tons a day, has been at work in the black vein about 20 years, and is one of the most fiery and dusty in my district. I might almost say, in the South Wales coalfield. The coal is a steam coal of the semi-bituminous class. It adjoins Abercarn and Risca Collieries, where in the same seam, as you know, there have been disastrous explosions. Blasting is not permitted, and discipline is strictly inaintained. "Meadow vein was a naked light pit up to 1890 when the disastrous explosion occurred there. It gave off some little gas, but I think about the year 1869 the most serious previous explosion occurred in it when seven men lost their lives. At the time of the 1890 explosion, killing 196 persons, it was being worked entirely with naked lights. "The Radstock Collieries have no gas, the seams are small and the coal, hard house coal and steam coal, and a good deal of powder is used in ripping roof. Explosions are unknown in these collieries except in connexion with explosives. About two years ago a man was burned upwards of 10 yards or so away from a shot in the floor. The man working in the stall above, and about 15 yards or so away, was slightly burned, the heat extending seven or eight yards further. I have no doubt that dust was an element in extending the flame in this case. No similar case was previously known there by any one, some of whom had 30 years' experience. " In the Forest of Dean. Firedamp is unkniown in this coalfield. The colliery has worked over 50 years. House coal; hard seams about 2 to 31 feet; roadways made (- feet in main ones, and 5 to 5 for gate roads. Powder used in ripping roof or floor. No explosion or extension of flame known." Mr. Wardell, H.M. Inspector of Mines, gives list of explosions in Yorkshire:Colliery. Lundhill - Edmunds Morley Main Warren Vale Swaithe Aldwarke Stanley Wharncliffe Carlton Altoft Thornhill Oaks Date. 1857 1862 1872 1874 1875 Killed. Seam:. Barnsley - - - - Do. Middleton Main Barnsley Do. 1875 Do. - - 1879 Silkstone Barnsley Silkstone Wheatley Barnsley - - 1883 1886 1893 - - - 189 59 34 23 143 7 21 20 22 139 300 or more. Middleton Main same seam as silkstone. Mr. Stokes, H.M. Inspector, writes :" Clay Cross Colliery, silkstone coal dust. Clay Cross Collieries, near Chesterfield, Derbyshire. The coal is both a house and gas coal, and is extensively sold in the London market. Celynen Colliery. Llanerch Colliery. Lightmoor Colliery. APPENDICES. "The mine is very dry and dusty. Thickness of seam from 5 feet to 5 feet 6 inches. It is the most highly bituminous coal in the county. Coal slack is extensively coked. Yields about 10,500 cubic feet of gas per ton. Depth from surface varies from 200 to 300 yards. An explosion of firedamp occurred in this seam at the No. 7 pit on November 7th, 1882, by which 45 persons lost their lives. Mine worked exclusively with locked safety lamps. Gas, frequently found. Blackwell "Deep Hard Coal Dust.-Blackwell Colliery, near AlfreColliery. ton, Derbyshire. This is, generally speaking, a steam coal. The greater portion of the seam being sold for steam generating, blast furnace, and other manufacturing pur. poses. Thickness from 3 feet 6 inches to 5 feet 6 inches. Depth from surface, 230 yards. Mine dry and dusty. Mine worked with naked lights. Blackwell " Low Main CoalDust.-This seam passes under the names Colliery. of Tupton coal, Furnace coal, and Low Main coal. It is sold for both house and manufacturing purposes. Thickness varies from 3 feet 6 inches to 6 feet. Depth from surface, 290 yards. Mine worked with naked lights and a few safety lamps. Gas occasionally found. Birley Bolliery "Silkstone Coal.-Birley Colliery, near Sheffield. This is Colliery same seam as the coal at Clay Cross, the previously described. It is called " Silkstone" in Yorkshire. Birley Colliery is within a few yards of the county boundary between Derbyshire and Yorkshire. The coal from this mine is extensively sold for gas making, and a large quantity is sent to the London market for house coal. Depth from surface, 290 yards. Mine very dry and dusty. An explosion of firedamp occurred in this mine on June 26th, 1876, when six persons lost their lives. Mine worked exclusively with locked safety lamps. Gas is frequently found, and occasionally outbursts of gas occur. Annesley " Top hardcoal.-Annesley colliery, near Nottingham. This Colliery. seam is called" Top Hard ", in Derbyshire, and Nottingham.shire, and it is the representative of the Yorkshire Barnsley bed. It is largely used for steam and iron making. A small portion of the seam (soft coal) is sold for house coal. Depth from surface 450 yards. Seam very dry and dusty. Worked exclusively with safety-lamps. Thickness variable, from 4 ft. 6 ins. to 7 ft. 6 ins." Mr. J. B. Atkinson, H.M. Inspector, writes : o n "Extensive explosion in the splint coal seam killing all 107. the men in it and extending over all the workings. 70 to 80 men killed. Year 1887, I think. Blantyre. "Extensive explosion in the Splint coal killing over 200 men. Year 1878, I think. Both Udston and Blantyre very dusty. Barrwood. Explosion causing loss of over 20 lives. Apply to Ronaldson as to this. " Dusty, but no explosion. Bent. "Udston, Blantyre, and Bent are in Lanark. Barrwood is I think in Stirling." Mr. Lewis writes:-Albion "In reply to yours of the 15th, I have pleasure in Colliery, sending a short history of the Albion Merthyr Upper FourFeet Seam of coal. "The Albion Colliery is situated about 14 miles from Cardiff in the Taff Valley in the county of Glamorgan, and is connected by railway with the seaport towns of Cardiff, Barry, and all other shipping ports. Operations were commenced at this colliery, January 1885. The four feet seam of coal was intersected at a depth of 545 yards on February 1887. There are two shafts, each 19 feet diameter. On December 21st, 1887, 1,100 tons of coal were raised. "Last year the output from this seam was 534,000 tons winding only from one shaft. "This company's workings are ventilated by a Schiele fan 15 ft. 6 in. diameter, making 46 strokes per minute, fly wheel of engine 20 ft. diameter, fan driving wheel 6ft. 6 in., producing 225,000 cubic feet of air per minute with a water gauge of 24 ins. "The mode of working is the Longwall system. "This seam is considered to be one of the most fiery in the district and has to be very carefully ventilated, besides giving off a quantity of gas, it is dry and dusty and artificial watering is resorted to. It is considered to be the best steam coal vein, and has been very extensively worked in this district, and in different places alters to some extent in section, a soft clod taking the place of the smooth partings, varying in thickness from 6 to 18 ins. It was first worked at Merthyr Tydfil and proved about 4 ft. thick hence the name of the seam. It generally works very freely, obtains the best price in the market and is most E 82480. 89 liked by the colliers. No explosion of any kind has taken place at this colliery. I enclose you a list of disasters in South Wales, those marked with a cross are (from information given, but may not be authentic) supposed to be in the Four-Feet seam of coal. Nearly all the disasters in this neighbourhood have resulted in consequence of the working of this seam. DISASTERS Date. IN SOUTH WALES. Name of Colliery. 1845, Aug. 2 - *Crombach 1846, Jan. 14 1848, June 21 *Risca *Victoria, Monmouth *Lletty Shenkin, Aberdare 1819, Aug. 11 . . 1852, 10 *Duffryn May 1853, Mar. 12 *Risca Vale *Cymmer 1856, July 15 1858, Feb. 25 *Lower Duffryn 1858, Oct. 13- *Duffryn 1859, Apr. 5 - Chain Colliery, Neath 1860, Dec. 1 - *Risca 1862, Feb. 19 *Gethin, Merthyr TydfilOct. 1863, 17- Morfa 1863, Dec. 24 Maesteg 1865, June 16 *New Pit, Tredegar 1865, Dec. 8 - *Gethin 1865, Dec. 20 *Upper Gethin 1866, June 16 *New Bedwelbty, Tredegar 1867, Nov. 8 - *Ferndale 186s, May 23 *Llanerch 1869, June 10 *Ferndale . 1870, July 23 Llansamlet 1871, Feb. 24 *Pentre 1871, Oct. 4 - *Gelli, Aberdare 1872, Jan. 10- Oakwood, Llynvi 1872, Mar. 2 - *Victoria, Mon. 1872, Mar. 8 - Weinfach . . 1874, Apr. 15 Abertillery 1874, July 24 Charles Pit, Llansamlet 1875, Dec. 4 - *Powel Duffryn, New Tredegar 1875, Dec. 5 - *Llan Pentyrch 1876, Dec. 18 Abertillery 1877, Mar. 8 - Worcester, New pit, Swansea . 1878, Sept. 2.- *Prince of Wales, Abercarn 1879, Jan. 13 *Dinas 1879, Sept. 22 *Waunllwyd, Ebbw Vale 1880, July 16 *Risca 1880, Dec. 10 *Naval Steam Colliery 1882, Jan. 15 *Risca 1882, Feb. 11 *Coedcae Iu upeast shaft 1883, Feb. 1 - *Coedcae 1883, Aug. 21 *Getty 1884, Jan. 16 Cwmavon 1884, Nov. 8 - *Pochin, Tredegar 1884. Jan. 28 *Penygraig *Naval Penygraig 1885. 1885, Dec. 24 'Mardy *Ynyshir 1887, Feb. 18 Aber Tynewydd 1888, May 14 Glyn Pontypool 1890, Jan. 24 1890, Feb. 3 - Llanerch Pontypool 1890, Mar. 8 - Morfa Port Talbot No. filled. li Remarks. 26 Upper 4 feet. 35 Black vein. 11 52 Upper 4 feet. 64 10 Black vein. 114 No.3 Rhondda. 18 Upper 4 feet. 20 9 feet. 26 145 Black vein. 47 Upper 4 feet. 30 Cribbur. 14 36 6 feet. 36 Upper 4 feet. 30 9 feet. 25 178 Upper 4 feet. 7 Meadow vein. 60 Upper 4 feet. 19 38 Upper 4 feet. 4 11 19 18 6 19 22 12 Black vein. 9 feet. 20 18 62 3 84 119 96 4 Black vein. Upper 4 feet. Big vein. Black vein. 6 feet. Black vein. 6 5 4 10 14 11 14 81 37 5 5 176 87 4 feet. 9 feet. 6 feet. 6 feet. Upper 4 feet. Meadow vein. Cribbur ,, Mr. Douglas writes: " The sample of coal-dust we forwarded you from this Usworth colliery was taken from the Main Engine Plane of the Colliery. Maudlin Seam (known on the Tyne as the Bensham Seam). " It is a seam that covers an extensive area in the eastern portion of the county of Durham, and is usually from 5 to 6 feet in thickness. " It is, in the Usworth district, a very high class gas coal, soft in its nature, and "works" exceedingly small. The districts from which it was collected are at a depth of about 240 fathoms. " On March 2, 1885, a very disastrous explosion occurred in this seam, causing the death of 42 lives. This explosion occurred actually on the Engine Plane and was fully described by Messrs. J. B. & W. Atkinson in their Treatise on Colliery Explosions. Those marked * within a radius of 12 miles, Black vein in Monmouthshire, supposed to be identical with 4 feet in Glam ranshire. NoTE.-The upper 4 feet is the same seam as the Aberdare or Merthyr 4 feet. H. I. M 90 Lightmoor Colliery. Llwynypia Colliery. Blackwell Colliery. Walker Colliery. ROYAL COMMISSION ON EXPLOSIONS "About the same time the great explosion in the Seaham Colliery, which is 6 or 7 miles distant, occurred in the same seam." Mr. Hale writes : " We forwarded to your address yesterday 1 cwt. 56 lbs. of coal dust collected from the sides of our headings, and from the rails in our underground roads in the twenty inches seam, upper series, of the Forest of Dean coal basin, as per instructions received from J. S. Martin, Esq., H.M. Inspector of Mines, Bristol. "We can send you more, if required, but we have nothing more inflammable in our workings, as water and not dust is our difficulty." Mr. Hood writes -"Referring to your circular of 27th ultimo, I beg to inform you that the sample of dust sent from this colliery was from the No. 3 Rhondda seam. We have never had an explosion in this seam here, but there was one at Dinas Colliery on the 1st January 1844, when 28 men were killed, and another in the same seam at Cymmer Colliery on the 15th July 1856, when 114 men lost their lives." Mr. Deacon writes:" In further reference to your circular of the 27th instant, the Low Main seam is a bright friable bituminous coal. The depth from the surface at the pit from which the sample was taken is 240 yards. It is the same seam as that generally known as the Tupton seam, which is worked at Clay Cross, Grassmore, &c. The deep hard seam consists of a layer of dull hards, below which is a mixture of hards and brights in streaks, which goes by the local name of "minge." This seam lies at a depth of 10 yards at the pit from which thesample was taken. "Both of the seams vary somewhat at different localities in the district. A few miles to the south, the Low Main becomes an unworkable seam, owing to its great friability, and the deep hard improves in quality for steam purposes: gradually hardening in its character until, at a distance of 12 miles south of these pits, it becomes a seam of almost entirely dull hard coal especially suitable for steam raising purposes." Mr. White writes: "I am exceedingly sorry I was unable to be at your coal dust experiments to-day at White Moss as I intended. "The dust I sent you was from the Beaumont Seam, 186 fathoms. ft. in. ft. in. Top coal 2 Oto2 6 Segarband Bottom coal - - - 1 0 4to3 8tol 0 0 " We have a good deal of gas, and work almost entirely long wall, with a fairly good ventilation, so that we are not so much troubled with it as one might expect. We had an explosion in this seam about September 1887, just before I came here, two men killed, and our neighbours at Hebburn Colliery had one in same seam about three years ago, four or five men killed. "We are also working a seam below this, so that we are the deepest colliery in Northumberland, 202 fathoms and certainly the most fiery. I do not think there are many worse in Durham. I shall be very glad if you could let me have result of your experiments at some future 'Aldwarke Colliery. Moston Colliery. time." Mr. Rhodes writes :"The seam from which the dust we forwarded to you was taken is known as the Parkgate Seam, and is worked by depths varying from 420 yards at the shafts to between 7,800 yards at the extreme deep of the workings. "The seam is 5 ft. 6 ins. thick, and has a rock roof, it is not liable to sudden outbursts of gas except when the first " break," comes on, and I think this is due to gas accumulating owing to the roof " swagging" between the face and the goof in consequence of its strong character, before finally breaking. " The seam is dusty but no shots are fired in the coal' and only water cartridges are used in stone drifting The roadways are watered to lay the dust as far as is practicable. "We have had no explosions in the seam, which is worked more extensively at these collieries than anywhere else in the district." Mr. Greensmith writes:"With regard to your inquiry re coal dust experiments. Our big mine has been worked at this place since the year 1830. I have been here only 12 years, during this time we have had no explosion in this mine, and I have made enquiry from old hands and they know of none. The seam is worked very largely. I only know of a small neighbouring colliery where the coal is worked outside our own place, and at this place naked lights were used until about 1 months ago, and then only introduced safety lamps owing tp the development of other seams, FROM COAL DUST IN MINES: "At a depth of two hundred yards the seam gives off no firedamp, but gives off blackdamp. As we go deeper into the measure we do find firedamp. The dust you experiinented with was swept from the ledges at what we call the 780 yards level. This level is at a depth of 615 yards vertical from the service. At this depth we never find blackdamp, but do occasionally find firedamp." Mr. Houston writes :" In reply to yours of the 18th instant, the seam of coal from which the dust was sent is called the Beeston Seam, the lowest thick seam in the West Yorkshire Coalfield, and has been worked a great many years round Leeds, and is not, as a rule, a fiery seam, though several explosions of gas have occurred attended with loss of life; it is a good house coal round Leeds, but as the seam extends eastward becomes more of a hard steam coal. "The dust we sent you was from the seam, and swept from the timber roof and sides, and collected in three bags which were labelled, Two bags were from the screen on the surface gathered up by men's hands. "The dust was not riddled, but sent as gathered." Mr. Wardle writes; "I should like to witness the experiments, as I don't think it will be possible for you to get an explosion from our dust, as the roof and floor is so dry and of a dusty nature that this dust mixes with any coaldust to such an extent that it will put a fire out instead of aggravate it." Mr. Dixon writes: "The dust sent from our Bent Colliery was the produce of the Ell and Main and Splint Seams. It was collected on the screens on the surface as the workings are damp. This being so, that from the Main and Splint Seams was mixed. "In regard to explosions, none have taken place in Bent Colliery. The extensive explosions at Blantyre and Udston Collieries, which are about a couple of miles away, were in the Splint Seam, the workings in these cases were very dry and dusty. The second explosion at Blantyre was in the Ell Seam, nwhich I think was also dusty." Mr. Richards writes :"The coal dust which was sent to you on May 30th from the Lewis' Merthyr Collieries, Hafod, was collected on the in-takes of the 4 ft. Seam at both our steam coal pits. "The large number of explosions which have occurred in South Wales, most of which I believe have taken place in the 4 ft. Seam; this is owing to the fact that this particular seam has been worked very extensively in South Wales, and has to a great extent drained the other seams partly of gas, and not because that the 4 ft. Seam contains more gas than the other seams when worked under the same circumstances." Mr. Asquith writes: " In reply to your letter of 1st instant, I find that the dust from our Beamish Colliery was gathered from the Busty Heapstead, above the Belts. "The Busty Seam has been opened out within the last six years, and a good deal of gas is driven off. No naked lights are used in the pit, and shot firing is no, allowed until the pit is done drawing coals. "An explosion Stanley, and 13 lives wvere lost. ing colliery, West occurred on 9th April 1882 at the adjoin- Peckfield Colliery. West Cannock olliery. Bent Colliery. Lewis' Merthyr Colliery. Beamish Colliery. "About 12 months ago, at the same place, the coal dust came in contact with a gas jet on the surface, which caused an explosion." Mr. " In Robinson writes:reply to your circular of the 15th instant, the Auckland samples of coal dust sent you were taken from the Harvey liery. and Brockwell Seams at Auckland Park Colliery. "The Harvey Seam is at a-depth of 110 fathoms, and the Brockwell Seam at a depth of 150 fathoms. "Both seams make gas and are worked with safety lamps, and have been at work about 30 years, but no explosions of any kind have taken place in them." Mr. 0-arvin writes:- "We are favoured with yours of 15th instant as to the Udston experiments about to be made with coal dust, and we Colliery. thank you very much for the invitation you have given us to witness the experiments. "The road dust we sent you was collected from the floor of our Splint Coal Seam, where a large explosion took place in May 1887, killing all the men and horses in the pit, with the exception of two men who were found almost dead within a few yards of the shaft bottom. We have never been able to account for this explosion, because the seam from the beginning till now has been exceptionally free from fire-damp, and yet the explosion extended throughout the whole area of the workings. The seam throughout was very dry and dusty, but, we used nothing but locked lamps except at the downcast ,bgttom. It is 9i APPENDICES. enerally believed that the dust had most to do with the isaster. "Blasting was generally prohibited. At the time of the explosion it was only allowed in two fast places. A shot, however, must. have been fired in each of these two places either at the time or some time immediately prior to the explosion. There were differences of opinion as to the exact time the shots were fired. '"Blantyre Colliery, which marches with the Udston Colliery, exploded in 1877, killing over 200 men. "The explosion at Biantyre occurred in the same seam as that at Udston, but there they had a larger area, the explosion extending over two working pits." Mr. Southworth writes:" In reply to yours of the 5th instant, the first explosion Hindley We had was on the 26th November 1868, by which 62 lives Green were lost; the cause was a blown-out shot. The second Colliery. was on the 15th November 1871, by which six lives were lost, caused by a blown-out shot, about 11 p.m. in a main road. There were two explosions in the Arley Mine at Ince Hall, one on the 23rd March 1853 and the other on the 18th February 1854. I do not remember the number of deaths (just now). "I think the Arley and Wigan Nine Feet (more commonly called the Wigan Six Feet) have played the most prominent parts in the explosions in the Wigan district." DESCRIPTION of the WEATHER during the EXPERIMENTS. Date. May , , , Temperature. 12 13 23 27 - June 8 ,, 9 - 700 800 580 600 D.B. W.B. 740-61-0 670--62o Date. - Fair. Fair. Fair but cloudy. Sunny. June ,, ,, July ,, ,, Very fine, Very fine. 22 23 24 6 7 8 Temperature. - D.B. W.B. 600-550 540-520 580-520 780--.650 820-68o 750 680 Dull but fair. Rain nearly all the day. Fair but dull. Fine and warm. Fine and warm. Fair, warm but dull. APPENDIX XXI. 1VEMORANDUM handed in by Professor H. B. DIxoN. June 1, 1893. IN accordance witthe terms of our Commission I visited the scenes of the explosions at Apedale, Malago, and Park Slip Collieries, and beg to make the following observati6ns on the circumstances attending the explosions as far as they concern the propagation of the flame by coal dust. 1. Apedale.-The explosion occurred 2nd April 1891. I visited the pit on April 8th. The intake was damp for a considerable distance. The explosion was started in a " thirling" by a blown-out shot of gelignite probably fired, according to the evidence given at the inquest, without any water in the " water-cartridge." A trace of gas was possibly present, for the seam gives off a little gas 'at the face; but the quantity of gas present was probably far too little to be detected. The shot was fired by an open lamp. The shot was stemmed with a highly bitumenous shale. The flame from the shot and stemming swept the floor which was covered with small coal. The explosion thus initiated travelled along the intake for some 200 yards, and stopped where the road became damp. The flame also traversed the adjacent workings and the return as far as they were dusty, and no further. Although it is possible that a trace of fire-damp was present in the immediate vicinity of the shot and in the returns, and aided in setting up the explosion, I think it in the highest degree improbable that any quantity of gas (which might at all have affected the explosion) could have been present in the air of the intake. Unless, therefore, we adopt one ofd the very improbable hypotheses which have been suggested, viz., that the flame r1eally travels in cracks and crevices above the roof-or that a sudden rush of air produced by an explosion can draw gases out of the sides which ignite, and thus popagate thte explosion-we are driven to conclude that the explosion was propagated along the intake by the raising and ignition of a cloud of dust. I collected samples of coked dust from the props, and of unburnt dust from the floor. I also took specimens of the "blackberry dirt " used for stemming, which I found to inflame readily, and to give off 13 per cent. of inflammable vapour when heated to dull redness out of contact with air. 2. Malago Vale.- examined the Argus and Malago pits on September 18th, 1891, 18 days after the explosion. According to the evidence adduced at the inquest, there canbe little doubt but that the explosion originated at the bottom of the Argus incline owing to the ignition of a mixture of fire-damp and air by a naked light carried by a workman. Whether there was a fall of roof liberating gas, as found by the jury, or whether the gas accumulated slowly in a nearly Vertical heading cgrnot be positively known. Gas had previously been fothnd in the vertical coal. The mine had not been worked from Friday night until the early hours of Monday morning when the explosion-occurred. It seems, therefore', probable that the gas accumulated in the vertical heading, and formed an explosive mixture with the air in the road below, where it was ignited by Burgess' head-lamp. The interesting questions for this Commission arehow far did this gas explosion extend, and what part was played by coal-dust in the subsequent propagation of the flame ? The Argus incline was exceedingly dry and dusty. The explosion traversed the lower workings, and passed right up the Argus incline a distance of more than 1,100 yards, breaking the thick wire guides in the shaft. The flame penetrated for some distance into the levels driven from the Argus incline, but in no case traversed any of these levels. Now if the explosive mixture of gas had been carried by the ventilation up the Argus incline, it would have traversed in turn the several levels leading from it along which the air current flowed. If the explosion, 'therefore, had been due to gas alone, it would have traversed the several levels. Since it did not do so, we must conclude that the explosion was propagated up the incline either by dust alone, or by dust and a quantity of gas too small by itself to make an explosive mixture with air. But it is known that no gas was observed at the time of the explosion by the examiners who were making their rounds in the higher levels (evidence of Charles Poultney); consequently the quantity 'of gas at the upper portion of the Argus inclile must have been under two per cent. or it would have been observed. The explosion therefore appears to have been propagated by dust thrown up into an atmosphere containing such gas, if any, as could not be detected by the official examiner. I have had the suggestion made to me by mining engineersthat the flame produced by an explosion of fire-damp and air would be extended (by the expansion of the gaseous products)though considerable distances beyond the region filled with the explosive mixture. For instance, one volume of methane mixea with 10 volumes of air would evolve on combustion sufficient heat to raise the temperature of the products of combustion to nearly 2,600' C., provided no heat were lost; at this high temperature the gases would occupy a volume nine times greater than their original volume. An explosive mixture occupying one-ninth o the mine might, therefore, it is argued, fill the mine with flame. Actually the propagation of flame in fire-damp mixtures is not very rapid, and the extension of the flame is not considerable. Experiments on a small scale, which I have made, show that even with the most explosive mixtures, i.e., those in which the loss of heat during the explosion is least, the total length of flame is about twice the length of the original column of explosive gases. In no case was the flame projected along a tube one and a half times the length of tle original column. In my opinion it is not possible that the explosive mixture, set on fire by the naked l-ight at the bottom of the Argus, could have produced a flame Sufficient to fill the whole incline unless it had found fresh fuel as it advanced. I am driven to the conclusion that the dust, which was abundant and very dry, was the main 92 ROYAL COMMISSION ON EXPLOSIONS agent in carrying the flame from the starting point of the explosion to the shaft. Radstock.-On December 2nd, 1891, I visited Ludlow's pit, Radstock, where a blown-out shot had fired the coal-dust and the flame had travelled a short distance. No fire-damp has ever been met with in this pit. The place where the shot was fired was strewn with small coal, but the path travelled by the flame was not "dusty" in the sense in which that word is ordinarily used in mines. The flame had left very slight indications of its passage; its extent was known by a workman being burnt. In this case the flame startedby the shot had died out in less than 50 yards. Park Slip, Tondg.-I visited this mine on September 12th, 1892, 17 days after the explosion. Owing to the flooding of the mine it was impossible to penetrate to the seat of the explosion, but I examined the main intake incline, which is also the road by which the coal is hauled. This haulage road is dry and dusty, the parallel return-air road is wet. The flame traversed the whole of the intake and was projected from its mouth; it did not traverse any portion of the return. From the evidence given at the inquest there can be no doubt that the explosion originated in the lowest workings, where gas was reported two hours before the explosion. Whether the explosion originated in the west or east workings of No. 8 Stage, on which point there was a difference of opinion, does not affect the uestion under discussion. Given an explosion of fireamp in No. 8 Stage, how was the flame propagated through the mine P The flame did not follow the air current. It extended throughout those parts of the mine that were dusty and did not penetrate into other parts. It is impossible that the main intake could have been filled previous to the explosion with an explosive mixture of fire-damp and air, or (in its upper portion) could have even contained the 1 or 2 per cent. of fire-damp which is admitted to be dangerous in the presence of dust. If, as I believe, the flame produced by an explosion of fire-damp in No. 8 could not, by the expansion of the gases, have been projected throughout the whole incline, it follows that the flame must have been fed by fresh fuel as it passed up the incline. In my judgment the dust, which was abundant and dry, in the incline (at all events in the upper portion which I examined) was the fuel that propagated the explosion to the mouth of the pit. The experiments of Mr. Hall's at Skelmersdale, which I have witnessed, have placed it beyond doubt that certain dusts, taken from mines, when thrown into the air and inflamed by a gunpowder shot do produce a veritable explosion of air and coal dust alone. The disturbance, once started, is sufficient to raise the dust from the surfaces on which it rests and to form an inflammable mixture of dust and air by which the flame is propagated as far as the dust extends. The quantity of dust strewn by Mr. Hall in the experimental shaft is not greater than that occurring in actual mines. His experiments show that dusts from different pits differ greatly in inflaminability. They also show that a great initial disturbance is required to start a dust explosion. The experiments prove conclusively, to my mind, that an explosion, once started in a dry and dusty mine, may be propagated throughout the whole of the workings that are dusty by the ignition of dust alone. . H. B. DIxoN. PosTsCRIrT, March 20, 1894. Camerton.-An explosion occurred in the New Pit at Camerton Colliery in the Radstock district on Novembei* 13th, 1893. On November 28 I made a careful inspection of the pit in company with Messrs. J. S. Martin, A. H. Stokes and W. N. Atkinson, Her Majesty's Inspectors of Mines. The extreme interest attaching to this explosion lies in the facts that firedamp is absolutely 'unknown in this coal field, and that the immunity from serious explosions enjoyed by this district for the last 100 years has been one of the chief arguments against the coal-dust theory. The origin of the explosion was a gunpowder shot in the stone roof of a self-acting incline about 350 yards yards distant from the face, and 2,100 yards from the downcast shaft. The incline constituted the intake air-way to the face of the workings. Owing to a "joint" or " fault" three inches beyond the end of the shot hole, the charge did not ,do the work intended, and blew down barely a hundredweight of stone. Nearly the, whole of the incline was dry and dusty, and there was as far as I could judge, more dust in the immediate neighbourhood of the shot than in the oiher parts of the incline. The flame was propagated both up and FROM COAL DUST IN MINES: down the incline, but practically no damage was done for 80 yards in either direction. Forty-five yards from the shot one of the men's candles was found still standing upright in its holder uninjured, except that "the wick was drooping." Inwards the chief damage was the smashing of doors and the overturning of trams standing at the top of the incline. Outwards considerable damage was done, the effects of the violence being evident for 1,300 yards from the source of the explosion. The explosion was confined to the intake airway, dying out inwards near the damp face and outwards where the road was wet and free from dust. In examining the mine, my attention was chiefly directed to testing for traces of fire-damp in such places as appeared most likely to contain it, if any had issued from the strata. The instrument I used was Professor Clowes' hydrogen lamp, with which I had previously had considerable practice both in laboratory experiments, and in gassy mines. I have satisfied myself that the lamp will show the presence of j per cent. of fire-damp in the atmosphere. Careful tests were made at two places in the returns, at the working face, and at the spot where the shot was fired. Tests were also made in three cavities in the roof where falls had taken place, and also at the entrance to an old road which extended a few yards into the goaf near the shot. In no case was the slightest indication of gas observed in the lamp. Mr. A. H. Stokes, testing at different places with his alcohol lamp, also failed to find any traces of gas. At my request, the incline was completely sealed up by stoppings in the intake and returns, between November 29th and December 8th. Mr. Martin examined the air when the stoppings were removed, and could detect no trace of fire-damp in any place in the mine. The evidence being thus conclusive that no trace of fire-damp existed after the explosion, and the testimony of those working in the mine being unanimous that no trace had ever been met with previously, although many faults had been cut through, the only conclusion possible is that this was a dust explosion pure and simple. Samples of dust cdllected at different places, were analysed by me with the following results :ANALYSIS OF DUSTS FROM CAMERTON COLLIERY. The samples were dried at 2120 F. before analysis. The ash left in each case was brown in colour, due to ferric oxide: Sample. Volatile 1. 2. 3. 4. 5. combustible 304E4 28*2 17"2 2464 18*45 - 44"44 45"6 31'81 38'25 15,98 25*02 26'2 50'99 37'11 100"0 100-0 matter. Fixed carbon Ash after burning - 100"0 1000 67"10 100"0 No. 1. Dust from ground of roadway near explosion. No. 2.Deposited dust from rollers near explosion (not there previously). No. 3. Dust from sides half way in from " Pump Corner." No. 4. Ordinary dust from bottom near pump corner. No. 5. Fine dust deposited on sides, 50 to 100 yards inside of " Pump Corner." It is to be observed that samples 1 and 2 are closely similar; the dust raised from the floor by the explosion being only slightly burnt. The dust contains a high percentage of volatile inflammable matter. If the flame travelled outwards to within 100 yards of the "Horse Gug," and I agree with Mr. Atkinson that the dust collected at that point from the timbers, had been heated to the softening point, the explosion must have leapt over several damp places. At the bottom of the incline the road was wet, but a train of full tubs standing there, may have supplied the necessary dust; but between the pump corner and the furthest point reached by the flame were two lengths of roadwajr which were wet. One was about 20 yards long, and the other about 35 yards long. This extensive explosion of dust in a non-fiery mine, taking place under ordinary working conditions, is the experimentum crucis required by those who did not admit that the artificial conditions under which Mr. Hall produced his dust explosions, were such as would occur in the ordinary working of a mine. The explosion at Camerton has indeed exactly fulfilled the conditions as to circumstances and place, demanded by one of the witnesses who gave evidence against the "dust theory." No artificial experiment could have been so complete and convincing. H. B. D. 1 /1 I\1 PLA N. ---. ROYAL COMMISE ---- -- I -- IJ 'T'-~-fe= -L~L~F_ lbo dhahwi _ _ - _ -- I I - i'-,<' EEEwas d7'dhflg t/z FaVeTON hole - I. I - SD '_ %.-,., ------.---..---- t - - _ * ,1j~~n~iWA TIWLEDL L. L4 SIDE EEVATIO SECTION AT A. A. ~ - SECTION AT A A. . - - - I. If ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST IN MINES. Appendix 1XX. (a) lo il#lratlc eridane,on £ EplosioM mNew Pt, Camerton Collkery. oot o (futded in, by Mr. JS._Marin), Scale 3 Chai/s to anuInek. 'N or 9A "5- 'ES N, Nufra4f lkwncast 7fathem.,o bdzrirce1 fix7&- ni / '~S / ~/ 4, I / 4' v BRANDON PLAN ROYAL COMMISSION SI()NS FROM, O 1'IN E S. 1APPENDIX A SHORT ACCOUNT BLOWN-OUT of ON EXPLOI(O )UST IN hen? tre& m& COLLIERY A OF PIT. PLACE mir banmed 1/raijt, a BlatiT'oat0 S ,ot VI. an ACCIDENT caused SHOT at BIRAiNDON COLLIERY, by dber /06'8&. a on the 10th October, 1884, put in by Mr. Tiowis BELL; see Minutes of Evidence, Question 1539. On the night of the 10th October four stonemen were employed in making refuge-holes in a stone drift on an engine-plane in the "Dun Cow Way " of the Busty Seam (66 fathoms), at a distance of about 600 yards from the shaft. At the place where the shot which caused the accident was fired the drift was 9 feet wide by 6 ft. 6 in. high, giving an area of 58j- square feet. The area of the drift for 20 yards on either side of that point varied from 60 to 80 square feet. It was an intake air-way along which about 20,000 cubic feet of air per minute passed, so that the velocity of the current at the point where the shot was fired would be about 340 feet per minute. A shot hole 2 feet long was drilled in the side of the drift, commencing about 3 feet from the thill at an angle of about 60"'(sce sketch). The man who charged the hole said he put in two cartridges of compressed powder 4" by 1a-" each; this would be 10 ozs., and that he stemmed the shot with the borings and small stone. 'When the shot was lighted three of the men went into a refuge-hole, on the opposite side of the drift, and 20 yards ilbye of it, and the other man retired 20 yards outbye into a similar refuge-hole. The drift was dry, and there was a considerable amount of coal dust on the floor, and adhering to the sides. When the shot exploded it blew the stemming and caused a flame,which extended outward to the man on that side, and slightly singed him, and inward past the three men on that side burning them all (two rather severely). When the place was examined afterwards there was found a plentiful coating of caked or partially coked dust on the sides of the drift, and a little on the top in different places. This coked dust could be traced for 18 yards outward, and 35 yards inward from where the shot was fired, the trace becoming gradually fainter and fainter in each direction. The trace of fire on the inbye side stoppAd just before it came to a point where a branch road joined the'drift. The drift appeared to have been full of flame for more than 50 yards in length. The powder in the men's bottles was not fired. The concussion caused by the explosion was felt at the shaft, and also by two men who were in the workings 1,100 yards beyond where the shot was fired. They said it Sput both their lights out, and they came out to see what was the matter. No damage was done except that a canvas stopping ,30 yards from the shot was blown down, and the lime was shaken off the stoppings for 300 ya rds. See diagram. REFERENCE A Poit ---C of JE7plosion. Distace~ ihm S toB-330 ~ 65 ,, 'y A5 . 168o. & . PM-WtII~ (S) ShalttopoitA3iooazs. S ,, Ao53 IWncatits ofY irr Irom C fto-D Z,31. JWod andl ~iz~aFt~~l zaw SStopitg8 blow out atB5E- 32. -B Judd & C? Ld, Lith- 6 3,Ca rter LaneIDoctors' Commons.3 69. 4B2. INDEX, 93 IN DEEX. See ABERDARE AND RHONDDA VALLEYS: under SouTH WALEs. ABERDARE AND RHONDDA VALLEYS COLLIERY OFFICIALS' ASSOCIATION: Represented before the Commission by Mr. John James Thomas; 6192. This association represents an output of eight million tons annually and 45 collieries; Thomas, 6267, 6268. Does not think that any of the members would say that an open light, or even a torch, would ignite coal dust. Believes that they are all in accord that a blownout shot, without any gas to commence with, may cause an explosion if fired into dust under certain conditions; 6269-75. ALTOFTS EXPLOSION: A dust explosion entirely; Ashworth, 4622; originated by a shot; 4623. The friction and heat of the explosive blowing out across the ropes, chains, rails, signal wires, &c. set up an electrical condition which disturbed the dust all along the roads; 4635, 4636, 4674-76. There was a space of from seventy to eighty yards on each side of the shot in which practically no damage was done ; 4654. Believes the shot faced the air current; 4720-24. A mine which makes a lot of gas. Thinks there must be some mistake with regard to the assertion that there was no gas present; H. W. Martin, 5529-5534. AMMONITE : Has used it for two or three years with gratifying results; as strong as any of the high explosives; no complaints about its showing flame or emitting fumes; Wilkinson, 5561, 5604. Uses no water cartridge with it; 5583. Considers it perfectly flameless according to his experience with it and the experiments he has made with it; 5585. Has had several blown-out shots with it; does not use it in the actual coal getting, but only in the roof; 5586-90. It is used in several places in the North of England, in Staffordshire, and in a number of places in South Wales; 5612. Might get a flame if no tamping were used; 5613-13. There is not much difference between the cost of working with ammonite and gunpowder; 561622. Has tested it by means of experiments and finds it has very little flash ; the flame is not strong enough, or continuous enough, to ignite dust; Thomas, 623036. APEDALE EXPLOSION: The friction and heat of the explosive blowing out across the ropes, chains, rails, signal wires, &c. set up, in witness's opinion, an electrical condition which raised the dust all along the roads; Ashworth, 4635, 4636, 4766. Description of the shot; 4648. A cartridge used without water; 4685, 4701, 4702. Gelignite, or gelatine dynamite, used in the same sized hole as they bore for powder; 4697-99. Caused by a shot at the working face; position of the shot; 4760-66. Witness has not visited the pit and only knows the circumstances from reports ; 4775, 4776. Position of the rails and pipes; 477784. See Professor Dixon's Report, Appendix XXI. ARDEER POWDER: Has tested it by means of experiments and finds that it gives very little flash; the flame not strong enough, and continuous enough, to ignite coal dust ; Thomas, 6230-36. Its composition; 6252. ASHTON IMOSS COLLIERY EXPLOSION: Caused by a blown-out shot; Ashworth, 4617. The dust was not ignited; 4618. Dust off the floor used as stemming; 4750. E 8248). ASHWORTH, JAMES : Mining engineer at Morley in Derbyshire; 4597. Attention first called to coal dust by explosions beginning in the year 1875; 4600. Examined the mine after the explosion at Swaithe Main, at Barnsley, in 1875; 4601-08. Describes an explosion at the Sheriff Pit, Silverdale, in 1878 ; 4609-16. Investigated explosions at Ashton Moss Colliery and at Sladderhill, Staffordshire; and at Wood Pit at Haydock ; 4617-21, 4775-84. Thinks the part played by coal dust in explosions important enough to justify special attention; 4622. Hands in a table showing the effect upon the atmosphere of an explosion of gunpowder ; 4625. Appendix XIV. Advocates the use of powder of the best quality in place of the common powder; 4626, 4678-85, 4687, 4744, 4745. Difficult to get a blown-out shot with such a powder; 4627-29, 4746-48. Is of opinion that every explosive should be used in a hole of reduced diameter in proportion as it is stronger than gunpowder; 4630-33, 4645, 46954704. Important that explosives should not be used in any case where there are ropes, chains, rails, or signalwires in the line of fire; 4634-37, 4667-76. Describes experiments with various lamps; 463841, 4704-12, 4733-43, 4767-74. Necessary with every safety lamp, if the mine is dry and dusty and gives out firedamp, unless the gauze is specially protected, that that lamp should have two gauzes; 4642. Watering of no value whatever, as it is impossible to properly saturate the dust; but an explosion may be arrested by having wet patches on the roads; 4643, 4644, 4713-19. No shot should face a strong current of air. This applies principally to the main roadways and not to the working-faces; 4646, 4720-24, 4759, 476566. Shots should be fired by electricity not by an ordinary fuse; 4647, 4725. The question of leverage, that is, the length of the charge, most important; 4648, 4690-94, 47514756, 4784-86. In the present state of knowledge all the so-called flameless explosives should be protected; 4649, 4650, 4686. In any experiments it is necessary to have an atinospheric velocity of from 30 to 50 feet per second, with a water gauge of not less than 2- inches, and ropes and chains should be provided; 4651, 4652. Suggests a syphon-shaped tube made in wroughtiron box girder form about 30 inches square, and not less than 150 yards long in a straight line; 4654; 4655, 4656, 4663-65, 4728-32. Thinks experiments should be made with various kinds of powder and other explosives; 4657, 4658. The fireman, or deputy, should examine a hole before it is charged, and should superintend the charging; 4659-62, 4726, 4727, 4749, 4750, 4757, 4758. Explains that three explosions follow a blown-out shot, and that unconsumed particles of gunpowder are thrown out and explode when they get mixed up with sufficient air; 4654, 4678, 4787-4809. ATMOSPHERE: Changes in the atmosphere caused by a blown-out shot of gunpowder; Ashworth, 4625, 4792-4802. Appendix XIV. AUSTRIAN COMMISSION: Extract from Report relating to Coal Dust. dix XIII. AppenN ROYAL COMMISSION ON EXPLOSIONS BEDLINGTON, RIcHARD: President of the South Wales Institute of Engineers ; engaged for fifty years in mining in Monmouthshire and Glamorganshire; 5658-62. During the whole olf his experience does not know of a single explosion in South Wales that has not been caused by gas; 5663, 5664, 5682, 5711-15. Considers that dust has played a part in the extension of explosions ; 5665. Does not think that coal dust produces an explosion in itself, but believes that it aggravates an explosion of gas; not, however, by flame so much as by coked dust, which scorches. Will extend the effects of an explosion to a limited extent; 566671, 5683-94. Does not consider the regulations of the Mines Act with regard to dust really necessary. According to his experience there has not been any case brought home in which even a blown-out shot has caused an explosion of the diust. Such a case is just possible, but there is no practical danger; 5672-74, 5707-10. Thinks it desirable to clear away the dust as a sanitary matter, but not to prevent danger; 5675, 5676, 5695. Does not believe it necessary to take any precautions with explosives except so far as gas is concerned; 5677-83. In the mines under his charge the dust is removed. ,Does not water as it softens the strata; 5696-5704, 5749. Uses powder, compressed powder, gelatine and dynamite; 5705, 5706. Insists that any experiments should be made with dust from a seam of coal that has n'ever been known to give off gas; 5715-29. Describes a blown-out shot in coal-dust; 5730-37. Does not think the flame of an explosion will continue as far as dust extends; 5738-42. Has examined mines after an explosion, but has never seen indications that the flame had passed over a certain portion of the mine, and, after an intervening space, had resumed its course; 574245. The mines of which he has had experience are dry and dusty; 5746-48. BELLITE: No practical experience of it; Ashworth, 4686. Has seen tests with it, but noticed no flame ; 'Morgan, 4828. Nothing near as effective as powder in bringing down the rock and hard ground which they have in South Wales ; 4834, 4835, 4846. Has tested it by means of experiments, and finds that it has very little flash; the flame is not strong enough, and continuous enough, to ignite the dust; Thomas, 6230-36. BLASTING: All the high explosives depend for their safety on the strength of the detonator ; Ashworth, 4629. Suggestions with regard to the size of the charge hole; every explosive should be used in a hole of reduced diameter in proportion as it is stronger than gunpowder; 4630-33. This is not the invariable practice ; 4695, 4696, 4700, 4703. Explosives should not be used in any case where there are ropes, chains, rails, or signal wires, anywhere in the line of fire, as the heat of the explosive blowing out across them sets up an electrical condition which disturbs the dust all along the. roads: Altofts, Elemore, and Apedale Explosions referred to as cases in point; 4634-36. The diameter of the bore hole should be properly regulated; 4645. In dry and dusty mines ordinary black powder should not be used, but only powder of the very best quality : every shot should be detonated; 4645. I o shot should fae: the current: this applies only where there is a Vtry strong current--in the main roadways principally, not at the working faces; 4646, 4720, 4759, 4765. All shots should be fired by an electric fuse ; 4647. The question of the leverage of the shot most.important; 4648. If regulations were made 'withregard to stemming, is of opinion that they The could be effectually enforced; 4659-61. fireman, or deputy, should examine the hole before it was charged, and should superintend the charging; 4662, 4726, 4727. Leverage the great test point; 4691-94.. Does not .say that fuse firing is altogether unsafe, but considers electric firing the safer of the two; 4725. Thinks the provisions of the Act FROM COAL DUST IN MINES: BLASTING--coninued. of 1887 which forbids the use of small coal for stemming is generally observed. In the explosion at Ashton Moss in 1891 the dust from the floor was used as stemming ; 4749, 4750. Desirable to leave a little of the coal that was holed on, rather than to run any risk by shutting it all off; 4751. Slines or partings in the coal; 4752-56. Marly floor dirt when damp a good stemming; 4757. In any amendment of the Mines Act it should be made compulsory for the fireman to examine the hole and to superintend the charge before firing ; 4758. Witness explains that by the term " leverage" he means the length of the charge; 4784-4786. The practice adopted in South Wales : Morgan, 48744876. The fireman does not examine the hole or the strength of the charge; 4877-4879. If there were such supervision it would reduce the number of accidents, but the number of men required would make the cost too great; 4880-4883. The better remedy would be to give the men some specific instruction in shot firing instead of leaving theim to gain their experience in a haphazard manner; 4884-89. If carried out, the law with regard to shot-firing is sufficient as it is; 4860, 4861. Seaham explosion caused by an ordinary shot in the stone-not a blown-out shot; Forman, 5056-58. Shot firing ought to be abolished in coal mines, no matter what kind of explosive is used-whether gunpowder, roburite, tonite, dynamite, or any of the other patent explosives-there will always be a danger of explosions in coal mines which give off a large quantity of gas; Woods, 5203. See also Mr. Woods' evidence under " Precautions." In 1887, the miners generally, with the exception of the South Wales district, were in favour of the prohibition of shot firing; Woods, 5204-15. Blasting at Dowlais Iron Company's collieries. See under ' DOWLAIs." A most serious thing if explosives were done away in the South Wales mines; Martin, 5445. Precautions taken in the Forest of Dean ; Brain,5813, 5814. Has invented an electrical fuse to supplant the time fuse. With it there is no tendency to miss fire; it dispenses with the use of a lamp to fire the fuse and avoids the danger of exploding any gas that may be present; 5819-25. Blasting at Camerton Colliery; Garthwaite, 63106317, 6417. Brown, 6522-25, 6561-66. Should be done by electricity instead of by a fuse ; J. S. Martin, 6607, 6656. See also under "BLowN-ouT " GUNPOWDER," SHOTS," "EXPLOSIVES," " PRECAUTIONS," " WATER CAR- TRIDGE," " ROBURITE," " SECURITE," " TONITE," " BELLITE," "ARDEEIL POWDER," and " AMMONITE." BLOWN-OUT SHOTS: Case of a blown-out shot at Sheriff Pit, Silverdale, in 1878; Ashworth, 4609. Thinks the dust that was in the air carried the flame to some extent, but the dust did not explode, and there was not much gas; 4610. The flame burnt and killed a miner about 60 yards distant from the shot, thinks the dust carried the flame; 4611. Did not notice any wet place; 4613. Generally speaking, in every big disaster which has occurred from a blown-out shot. the shot has faced the current; 4720. Refers to the explosion at Ashton Moss Colliery which was caused by a blown-out shot; 4617. The dust was not ignited; 4618. States that when there is a blown-out shot, particles of unconsumed powder are blown out from the shot-hole, and, when mixed with sufficient air, burst into a second explosion; 4654, 4787, 4788, 4803-4806. Not a common case for unconsumed powder to be blown out: the shot would have to be largely over-powdered; 48074809. From personal observation believes that in the majority of cases blown-out shots do not give off flame; Morgan, 4817, 4849-52, 4855, 4890-96. His experience is that there is generally a flame with blown-out shots; Isaac, 4956, 4966. Blown-out shots are caused by undercharging as a rule; also to insufficient tamping and to inexperience; 49594965, 5028-5034. Describes a case in which a blown-out shot exploded gas ; 4967-75. Refers to experiments at Dowlais by Mr. Galloway in which blown-out shots ignited the dust; Martin, 5479-82. Risca explosion caused by a blown-out shot in dust; Wilkinson, 5539. INDEX. BLOWN-OUT SHOTS-continued. Has seen a blown-out shot in a dry and dusty place; Bedlington, 5730-37. See the two cases of blown-out shots described by Mr. Brain and Mr. McMurtrie, under " RADSTOCK DIsTR CT." Has seen a blown-out powder shot, under ground; would say the flame extended 5 or 6 feet, in a place which is damp naturally: Hood, 6024-27. BRAIN, FRANK: 95 BRANCEPETH-THE EXPLOSION IN A HOPPER: Thinks that this explosion was due to gas given off by the coal dust; Thomas, 6206-209, 6253, 6254. If tested with a safety lamp under' the same circumstances thinks it would be found that gas was present; 6287, 6288. BROWN, JOHN: Examiner and Fireman, Camerton Colliery, near Radstock; 6492, 6547-54. Describes the condition of the New Pit as regards ventilation, gas and dust; 6497-504, 6522-32, 6561-68. The position of the shot, the amount of charge, and the quantity of dust in the neighbourhood; 6505-21, 6537-46, 6555-60. Member of the Institute of Civil Engineers; member of the South Wales Institute of Mining Engineers; on the executive council of the National Association of COlliery Managers; manager of the Trafalgar Colliery in the Forest of Dean; associated with the working of the Forest of Dean Collieries for the BRYNN HALL COLLIERY EXPLOSION: past twenty years; 5750-56. Particularly well ventilated: difficult to detect the Of the opinion that it is decidedly impossible for dust gas in the nine feet seam; Woods, 5257. to initiate an explosion; 5757-59. Explosive gas has never been found in the Forest of CAMERTON COLLIERY: Dean, and the Collieries of this district have been quite free from explosions; 5760, 5761, 5863. Explosion in New Pit, 13th November 1893; two Has made extensive inquiries, and believes that an lives lost ; Garthwaite, 6321, 6324-26. explosion caused by dust has never occurred in the Description of the seams worked; Garthwaite, 6298Forest of Dean; 5762. 6302. Some of the Dean Forest mines are dusty, and shot The colliery has been worked for upwards of a firing with gunpowder is largely practised; 5763, hundred years without any trace of gas, and 5764. witnesses are convinced that it played no part in Has never known a blown-out shot in these collieries the explosion; Garthwaite, 6303-306, 6349; J. S. to be followed by any kind of explosion; 5765, Martin, 6581-83, 6627, 6628. 5766. No precautions whatever have been taken against gas Refers to the explosion at Ludlow's Colliery, at or dust; Garthwaite, 6307-9, 6385-88, 6427-30; Radstock, which was caused by a blown out shot; Brown, 6497, 6498, 6502-504; J. S. Martin, 6661. 5767-71. Would hardly call it an explosion, but The mode of blasting, and the number of shots fired; looks upon it as a prolongation of the flame of the Garthwaite, 6310-17; Brown, 6522-25, 6561-66; blown out shot, and, taking that view of it, thinks J. S. Martin, 6629-33. it strongly confirmatory of his opinion that coal Does not consider the New Pit dusty; Garthwaite dust, as found there, would not cause an explosion ; 6318-19, 6421-24, 6458. 5772, 5773, 5800, 5835-83. Abundance of coal dust Description of the place at which the explosion was at the point where the explosion, or inflammation initiated, the position of the shot, and the amount ceased; and no dampness whatever ; 5778. Refers of charge; Garth~waite, 6321-22, 6336-93, 6419, to the quality of the dust; and fails to see, if the 6425, 6426, 6431-40, 6447-52, 6458, 6463-65; Brown, coal dust was sufficient to carry the flame thirty or 6499-501, 6505-21, 6537-46, 6555-60; J. S. Martin, forty yards, why it should not carry the flame 100 6617-22, 6671-83. or 150 yards; 5779-94. Two shots were fired; Garthwaite, 6323, 6328-33; Believes that it is not possible for coal dust to carry J. S. Martin, 6657-59. on an explosion to any great length; it may add The indications of the second shot; Garthwaite, 6327, fuel to the fire, but it dies out in a short distance; 6335. 5774. Dust was in the air when the second shot was fired ; Reads resolutions passed by the managers of the Garthwaite, 6334. Somersetshire, Bristol, and Dean Forest Collieries, The position of the bodies; Garthwaite,6338-40. which affirm that dust in the non-fiery seams of Charring of timbers, coked dust, &c.; Garthwaite, these districts will not per se cause an explosion, 6341, 6342; J. S. Martin, 6701. and has never been known to explode; and also The course of the explosion, the description of the contain suggestions with regard to experiments; roads as regards dust, &c.; Garthwaite, 6343, 6344, 5795-99, 5919-22. These resolutions do not hold 6401-404, 6468-79; J. S. Martin, 6587-94, 6641, good with regard to the fiery seams in the districts 6642, 6687-6700. named; 5904-909. There were little indications of violence for some Thinks the .general rules, of the present Act with distance on both sides of the shot; Garthwaite, regard to watering and shot-firing are sufficient; 6345, 6400, 6416, 6417; Brown, 6533-36. 5801-804. The explosion terminated at a damp spot; Garthwaite, So far as the Forest of Dean is concerned, does not 6346; J. S. Martin, 6592. think that these regulations are necessary; 5805The explosion was initiated by the firing of an over12. charged, or partly blown-out shot, and carried on Does not use flameless explosives, and would certainly by coal dust without the presence of firedimp; not prohibit gunpowder in the Forest of Dean; Garthwaite, 6348, 6371, 6372, 6391, 6392, 6415; 5813-18. J. S. Martin, 6580, 6581, 6595, 6596, 6599. Has made a study of blasting with a view to supplant Reasons for the non-occurrence of similar explosions the time fuse by an electric fuse, and the system in past years; Garthwaite, 6350-52, 6414, 6441, has been very largely adopted in many parts of the 6442. country; 5819-25. The explosion died away as it approached the working Refers to the Report of the Prussian Commission with faces where the dust is damp and mixed with regard to the distance to which the flame from shale; Garthwaite, 6368-370; Brown, 6526, 6527, coal-dust, or an explosion of coal-dust, might be 6567, 6568. continued; 5825-34. Gas has never been found in the faults, nor in the Does not give any opinion upon matters in general: goaves, nor has come off in the case of falls; confines himself to his own district; 5883-88. Garthwaite, 6373-84, 6405-13, 6430, 6445, 6446, Does not find it necessary to put into force the 6453-6457, 6480-85 ; J. S. Martin, 6627. provisions of the Mines Act with regard to dust; Reasons why the first shot did not cause an explosion 5889-91. while the second one did; Garthwaite 6395-99; Does not think it dangerous in the Forest of Dean J. S. Martin, 6612-16, 6623-27, 6684-86. Collieries to fire more than one shot at a time; Open-end trams used; Garthwaite, 6459-62. 5892-94. No trace of gas discovered after the explosion; Draws a distinction between the explosion, and the Garthwait, 6486-88; Brown, 6528-32, 6547-54; mere inflammation, of coal dust; 5895-5903. J. S. Martin, 6584-86, 6598, 6704-14; DiDon, In reference to experiments suggests that a chamber 6723-31, 6736-38. on the surface should be built four hundred or five Position of the stoppings put in after the explosion; hundred yards long and about six by seven feet Garthwaite, 6489-91; J. S. Martin, 6702, 6703. wide ; 5910-22. See Professor Dixon's report, Appendix XXI. N-2 96 ROYAL COMMISSION ON EKPLOSIONS CLIFTON HALL EXPLOSION: Gas brought down by fall of roof ; Woods, 5258. CLOWES' HYDROGEN LAMP: Detects one quarter per cent. of firedamp; Dixon, 6724-26, 6729. COAL DUST: The part played by coal dust in explosions important enough to justify special attention; Ashworth, 4622. A danger to be guarded against; Isaac, 4942, 4958. The dust in the travelling roads finer than that at the working faces, and more dangerous; 49985009. Plays an important part in explosions; Forman, 5037. Believes that it always gives off a little gas, but more when it is fresh; Thomas, 6276. COAL DUST AND NAKED LIGHTS: Does " not believe that the coal dust in Wales is so "'sharp' that it would ignite at once, by the light of a candle as it were"; Morgan, 4818. Does not agree with Mr. Galloway on this point, and thinks he is going to extremes; 4925, 4926. Thinks the miners in South Wales generally agree with witness's opinion in this respect; 4927. Has noticed the dust igniting in the gauze of his lamp; Isaac, 5021-23, Does not believe that a naked light has sufficient flame to ignite or explode coal dust; Hood, 5928. Coal dust will ignite at a torch but the dust must be so thick that it would be impossible to live in such an atmosphere; 6034. From his observation of dust about the tips, where there are fires and large comet lamps, believes that coal dust alone will not explode at a naked light ; Thomas, 6204, 6205, 6255, 6256, 6291. Believes that the explosion in the hopper at Brancepeth was caused by gas given off by the dust; 6206-9, 6253, 6254. Has seen dust in the roads so thick that it was almost suffocating; yet under such conditions believes there is no danger wiih a naked light so far as dust is concerned; 6210, 6211. Dust raised at the working faces by falls of roof fails to explode at a naked light; 6212-4; 6219, 6220. From practical experience is convinced that coal dust will not explode at a lamp; it burns and inflames, but does not explode; 6221-3. A large light, such as a, torch light, would not ignite the dust without the presence of gas; 6257-66. COAL DUST AS THE MEANS OF INITIATING AN EXPLOSION, WITH THE FLAME FROM A SHOT AS THE EXCITING CAUSE, AND IN THE ENTIRE ABSENCE OF GAS: Witness explains how unconsumed powder is ejected from a blown-out shot and bursts into a second explosion when it becomes mixed with the atmosphere; how the friction and the heat of the explosive blowing out across ropes, chains, pipes, and signal wires set up an electrical condition which disturbs the dust all along the roads and spreads the flame throughout the mine instantanecusly; Ashworth, 4635, 4654, 4667-71. Electrical conditions caused by the rubbing of the chains, &c.; witness does not know how it happens, " but a sort " of electrical wind takes place, and throws the " dust off the various points all along the roads "; 4672. In the Altofts explosion does not think the blown-out shot was able to raise sufficient dust to cause the explosion, which he attributes in part to the presence of chains and other iron work; 467476. Three explosions follow a blown-out shot; 4793-97. Does tlot believe that a blown-out shot will, in the absence of gas, ignite the dust and cause a terrific explosion; Morgan, 4817, 4855, 4856. Believes that coal dust will cause an explosion in itself when the air is very hot in fiery mines; Isaac, 4939, 4940. A blown-out shot might cause an explosion in a dusty mine; 4957. Cannot say that he has had a blown-out shot which has ignited the dust; 4967. When the air is allowed to travel over a large area it becomes very hot and polluted, and when coal dust is mixed with it, believes it will explode, even when there is no gas which could be detected with a safety-lamp; 4944. FROM COAL JDUST IN MINES: COAL DUST-continued. A blown-out shot, or an ordinary strong shot, if it is overcharged, will cause the dust to ignite; Forman, 5038-44, 5119-21, 5137. Explains that after ignition the temperature of the dust rises until it explodes; 5045-48. The quantity of dust in the air in the ordinary working of a pit is not sufficient to explode, but it must be raised by a shot, and there must be a large quantity of fine dust adhering to the sides, timbers, and floor ; 5049, 5050, 5121, 5149. Believes that coal dust cannot initiate an explosion; Woods, 5185. Has worked in the most dusty mines imaginable where gunpowder was used ad libitum, yet never saw the slightest trace or danger of an explosion arising from dust; 5186-88. Describes an accident with a shot at a working face; 5194. From the large flame that was given off on this occasion concludes that if a blown-out shot can ignite dust it would have done so in this iistance; 5263-92. Coal dust as we see it in the general working of collieries will not cause an explosion in the absence of gas ; H. W. Martin, 5350, 5476, 5501. Has never known a case in which dust has been ignited by a blown-out shot and without gas; 5482-84. Thinks it impossible; 5485-88. Risca explosion caused by a blown-out shot in dust; Wilkinson, 5539. See also under " RIsca ExPLoSION." Coal dust a very serious danger, and may be the cause of an explosion even without gas; 5549, 5550. Will not in itself cause an explosion; Bedlington, 5666. According to his experience there has never been a case brought home in which a blown-out shot has caused an explosion in dust; 5673, 5684, 5707-10. Of itself not a serious danger; 5693, 5694. Is decidedly of the opinion that coal dust will not initiate an explosion without the presence of gas; Brain, 5759. See Mr. Brain's evidence under ' RADSTOCK DISTRICT." Coal dust is inflammable without the presence of gas other than that contained in itself;. Hood, 5925. To set up the inflammation an explosion is not necessary, but it will explode or inflame by simple contact with the heat; 5926, 5927. Describes how coal dust ignites or explodes at a coke oven: the flames reach a distance from the oven of from six to eight feet; 5929, 5997-6001. There must be a considerable body of heat to ignite the dust: a blown-out shot of gunpowder would be sufficient without the presence of gas; 5930-33. See also under " PEN-Y-GRAIG" and the "NATIONAL COL- LIERY EXPLO.sIONs." Believes that ordinary shot firing will not cause either a lengthened flame or an explosion in a coal mine: speaks more particularly with regard to his own experience and the class of dust in the mines that he has to deal with; would rather not express an opinion upon such dust as is found in the Rhondda Valley; McMurtrie; 6146-6150. "Where the flame " froma blown-out shot is in immediate contact " with the dust it will no doubt cause combustion, " and that may extend to other coal dust, and so it " may be extended along the face; but the effect ,"rapidly decreases, and at the end of 30 yards " practically dies out '";6177. See Mr. McMurtrie's evidence under " RADSTOCK DISTRICT." Dust which would not be dangerous with an ordinary naked light might be very dangerous in the presence of a blown-out shot from gunpowder or a low explosive, or in the presence of an explosion from firedamp; Thomas, 6216-18, 6237, 6290. Since the explosion in the New Pit, Camerton Colliery, is of the opinion that coal lust per se may cause an explosion; Garthwaite, 6348-71, 6372. Has been convinced by the explosions in Ludlow's Pit, Radstock, and in the New Pit, Camerton, that coal dust per se may cause an explosion; J. S. Martin, 6572-82, 6600. COAL DUST AS THE MEANS OF RENDERING FIRE-DAMP MORE DANGEROUS, AND OF INTENSIFYING AN EXPLOSION OF FIREDAMP : Describes an explosion at Swaithe .Main, at Barnsley, caused by a mixture of gas and suspended coal dust passing through the gauze of a Stephenson's safety lamp ; Ashworih, 4601-608. Experiments INDEX. 9P COAL DUST-continued. An explosion once set up may be continued as long with lamps show that a lamp in an atmosphere as dust exists; Hood, 5934, 5935. containing 4 per cent. of gas will fail in 20 seconds if anything should disturb the dust; 4640. Coal dust will extend the flame of an explosion, but only for a very limited distance; McMurtrie, 6128, Does not believe that coal dust causes explosions, but, 6129, 6130. The presence of coal dust a danger, when a gas explosion takes place, the dust is raised but a very slight one; 6131. Where the flame and kindled by the flames; Morgan, 4816. If an from a blown-out shot is in immediate contact explosion of gas takes place it most decidedly could with the dust, it will, no doubt, cause combustion, be carried on to greater distances, with the aid which may extend to other coal dust, and so it may of coal dust, than it would otherwise go; 4819. be extended along the face, but the effect decreases, Therefore, the presence of coal dust is a source of and at the end of 30 yards practically dies out danger; 4820. Where coal dust is present the exaltogether; 6177. See Mr. McMurtrie's evidence plosion is likely to be more fatal than it would under " RADSTOCK DISTRICT" upon the two cases of .otherwise be, especially when the place is extremely blown-out shots there. hot. The smaller the dust the more effective it is ; 4821. A blown-out shot would be attended with Believes that coal dust is a danger in a mine in carrying on explosions initiated by some other cause, considerable danger where there is dust, and a small and is of opinion that it can carry on an explosion quantity of gas, but the place must be hot; 4853. for a considerable distance; Thomas, 6198-6202. When the air is allowed to travel over a large area it If there were an explosion of gas in a place where becomes very hot and polluted, and when coal dust is mixed with it, witness believes that it will there was a considerable quantity of dust the explosion might be continued, and extended, and explode even when there is no gas which could be increased; 6217, 6218, 6238. detected with a safety lamp; Isaac, 4939, 4940, 4944. Where there is a small quantity of gas the presence COAL DUST-QUANTITY IN SUSPENSION IN THE AIR: of coal dust very much stimulates and increases the power and danger of an explosion; Forman, 5137. The experiments that have been made do not repreCoal dust may increase ana intensify an explosion sent the ordinary conditions of a mine in this of fire-damp ; Woods, 5184. respect ; Ashworth, 4637. Coal dust aggravates explosions initiated by fireThe quantity of dust in the air in the ordinary workdamp; Martin, 5347. It will increase the danger ing of a pit is not sufficient to explode; it must of such an explosion and extend it; 5348. It be raised from the ground, and the sides, and renders gas more liable to explode; 5349. Refers brought down from the timbers by the concussion to the explosion at the Pochin Pit, Tredegar, and from a shot; Formnan, 5049, 5050; great concusbelieves it was initiated by gas alone and aggrasion required to raise the dust-some shots do not vated and extended by dust; 5362-65. raise enough dust; 5121, 5149. According to the gas there will be an amount of flame, and the flame licks up the dust in the COAL DUST-ITS INFLAMMABILITY VARIES immediate vicinity and cokes it; the scorching at IN DIFFERENT KINDS: great distances is caused by the heated air and by Has no doubt that some kinds are more explosive the coked dust; Bedlington, 5665. Coal dust than others; Morgan, 4818. aggravates an explosion of gas; 5666. Does not The coal dust in the travelling roads finer than that think it adds much to the flame or to the explosion ; at the working faces and more dahgerous; Isaac, 5667-71. 4998-5009. The coal dust about the tips, on the roads, at the The dust in the working faces comparatively safe; faces, and in confined places, may add to the force Forman, 5081. of an explosion initiated by some other cause; The shale and stone dust produced by the roof Thomas, 6201-203. Renders fire-damp more liable ripping and bottom cutting in South Wales make the to explode; 6225. dust less liable to burn or inflame; I. W. Martin, 5353. Refers to Mr. Galloway's experiments with COAL DUST AS THE MEANS OF PROLONGdifferent kinds of dust in South Wales in which ING OR EXTENDING AN EXPLOSION it was found that only the dust from the Rhondda HOWEVER INITIATED: Valley was explosive; the dust obtained from the neighbouring collieries failed to explode; 5355-60. For a short distance an explosion may be extended The quality of the dust varies; Hood, 6012. by means of coal dust; Woods, 5194. But only in exceptional cases; 5293-5295. COAL DUST EXPLOSIONS: Is certainly of opinion that it will carry on an exThese explosions go in some cases with the air plosion; Isaac, 4941. current, and in others against it; the direction As long as there is dust in the air to feed the flames depends upon the place of ignition and the track the explosion continues; Forman, 5048of the dust; Forman, 5052. If the flame reach the fine dust in the upper part of No force is exhibited for about 60 or 90 yards on each any of the galleries it would be ignited, and would side of the shot; in a gas explosion force would serve to extend and carry the explosion further; be exhibited at once; Formcan, 5074-6. but only to a limited extent; Bedlington, 56835692. Does not think the explosion would con- COAL DUST-CAKED: tinue along the galleries so far as the dust extended Has never seen caked or coked coal dust after any because the flame due to the explosion of the gases explosion; is suspicious of the statements as to its would become weaker and weaker; 5738-5745. existence; Woods, 5195-200, 5247-51. Considers it proved by Sir Frederick Abel's experiments at Wigan and at Chatham. and also by the DIXON, P orassox H. B.: Prussian experiments, that coal dust alone could Of University College, Manchester, and a member of not cause an explosion, but that where flame is the Commission. HIas made many experiments given off by the firing of a shot of gunpowder, the with various safety lamps, and finds that Professor flame would, under certain conditions, ignite the surrounding coal dust, and would be considerably Clowe's hydrogen lamp detects one quarter per cent. of fire-damp; 6723-6, 6737. He tested the elongated by the addition of the flame of the coal air with Clowe's hydrogen lamp in several places dust; Brain, 5773. It is not possible for the coal at Camerton Colliery after the explosion and could dust to carry on the explosion to any great length; detect no trace of gas ; 6727-31, 6738. it may add additional luel to the fire given off from Has visited the scenes of various colliery explosions; another cause for a few yards, but the ignition, or 6732-5, Appendix XXI. inflammation, dies out at a short distance com. paratively speaking; 5774. The coal dust itself, in the entire absence of gas, (which are the con- DOWLAIS IRON COMPANY'S COLLIERIES: ditions existing in the Forest of Dean Collieries) Output last year ; I. W. Martin, 5332. Produce steam is not a sufficiently explosive element to carry coal and bituminous coal; 5335, 5512. Not what the flame to any appreciable extent; 5794. are called dusty mines; 5336, 5345. The Evan 'Differentiates between an inflammation and an Thomas bonneted clanny is in use in some of the explosion of coal-dust; 5895-5903. See Mr. Brain's collieries: naked lights in others; 5337, 5420. evidence under " RADSTOCK DISTRICT," upon the case Shot firing at the rate of 383 to 400 shots per day; of a blown-out shot at Ludlow's Pit. 5339. The steam coal collieries are subject to fireN3 COAL DUST-continued. 98 ROYAL COMMISSION ON EXPLOSIONS DOWLAIS IRON COMPANY-continued. :lamp: the bituminous collieries entirely free from fire-damp; 5340. Naked lights used in the steam coal collieries; 5341, 5342. Several slight explosions have occurred in the steam-coal collieries: none whatever in the bituminous; 5344, 551316. For the spray system of watering at these collieries, see Mr. Martin's evidence under " WATERING." Working all the known seams in the Merthyr and Aberdare Valleys; 5417. 'Thinks the most dusty seam is the nine feet; 5418. As to which seam is the most fiery, it depends on the kind of roof and the position of other seams above and below; 5419; Are working with naked lights where there are precautions against dust, but not where the dust is considered dangerous, or where there is gas; 5421-30. Watering adopted as a preventive against danger; 5431-5437. Explosives very largely in use; 5438-5442. No complaints with regard to fumes from gelignite or roburite; 5496-5499. The workmen examine the mines under the 30th general rule if they choose to do so, but they do not care about giving up the time; 5477, 5478. Remove the dust in trams; not necessary to brush it away, if watering is carried on; 5509-5511. All the pits except the bituminous worked by longwall; 5517, 5518. The precautions taken when shot-firing; 5519-5522. Does not know that they have had a single explosion caused by firing into gas; 5523, 5524. ES: DURHAM COLLIERI Would prohibit gunpowder altogether in the county of Durham; Forman, 5086-5091. Would not think it necessary to prohibit the high explosives as they are much safer; 5092-5102. Gunpowder is largely used in the west but not in the eastern portion of the county; 5103-5108. The wedge referred to: not extensively used in Durham; very severe work and the men prefer to use roburite; 5122-5129. The provision of the Mines Act which enables the men to examine the mine is put in force, but rather with regard to the ventilation and the roof than to dust; 5130-5136. There are means of watering, but it is not done, witness believes, at the working faces; 5141. Cannot conceive of gas being present in the rock in Durham; 5154-5156. Only the more intelligent of the men think there is any danger in coal dust; 5164-5166. DUST-TIGHT WAGGONS: recommended; waite, 6415, 6416. Garth. DYNAMITE: Described as being highly inflammable and having a large flame; Isaac, 4992, 4993. Use it in strong rock, especially after a blown-out shot of gunpowder, 4995. The fumes from it are worse than those from gunpowder; 4996. Used for rock roofs; Bedlington, 5705. ELECTRIC FUSE: Has invented a system of electric firing, which he describes; Brain, 5819-25. ELECTRICAL CONDITIONS: Produced by a shot blowing out across ropes, chains, rails, signal wires, &o.; the explosions at Altofts, Elemore, and Sladderhill, referred to as cases in point; Ashworth, 4634-37, 4668-76, 4766, 4775-84. ELEMORE EXPLOSION: Entirely a dust explosion; Ashworth, 4622. Originated by a shot; 4623. The friction and heat of the shot blowing out across the chains, rails, signal wires, &c., would in witness's opinion set up an electrical condition which disturbed the dust all along the roads; 4635, 4636, 4670, 4671, 4676. The shot faced the air current.; 4720. A dust explosion; Forman, 5069-73. COMBY TH E MADE EXPERIMENTS, IF MISSION: They should represent the conditions of a mine, that is, they should be made in a velocity of air passing at from 30 to 50 feet a second and with a water gauge of not less than 2' inches. Rails, ropes, and chains, should be provided to prove whether these in conjunction with a blown-out shot set up electrical conditigns which disturb the dust from FROM COAL DUST IN MINES: EXPERIMENTS- continued. the tops of the timbers and the sides of the roads; Ashworth, 4652. Suggests a tube made in wroughtiron box girder form about 30 inches square; 4654, 4655, 4728. The chamber should not be less than 150 yards long in a straight line, and should be syphon shaped to represent the upcast and downcast pits; thinks that the telephone might be used to record the vibrations caused by a blown-out shot; 4656. Thinks experiments should be made with the various kinds of gunpowder and other explosives; 4657, 4658. Is of opinion that it is not necessary to have a gallery the same size as the gallery of a mine; 30 inches square would be big enough; 4663, 4664. Believes that experiments in such a chamber would be accepted as conclusive; 4665. Suggestions as to the shape of the chamber; 4729-32. Thinks that the Commission should make experiments to settle the question;' Forman, 5158. The gallery should not be less than a quarter of a mile long as the force of the explosion gradually increases, and in the first stage is merely an ignition; 5159. The gallery should be the same size as the gallery of a mine; 5160, 5161. In order to be clear of gas it should be on the surface; 5162. Experiments in a disused mine would not be accepted as conclusive; 5163, 5174, 5175. Perfectly satisfied without further experiments that dust is dangerous, but believes there are still people who desire further proof; II. W. Martin, 5502-04. Further experiments are certainly necessary as there are still a great number of people who do not believe in the danger of coal dust; Wilkinson, 5644, 5645. A chamber two or three hundred yards long would hardly meet the case; it should be about eight feet by seven feet-the width of an ordinary heading: should be on the surface; 564655. The experiments most required are those which relate to the comparison of different kinds of explosives; 5656. Would be.an advantage to convince the workmen of the danger of coal dust; 5656, 5657. To prove that coal dust will cause an explosion in the absence of gas thinks that the experiments should be made with dust from a vein of coal which is known to be free from fire-damp; Bedlington, 5715-29. Suggests a chamber built on the surface corresponding in size to the roadway of a coal face of the Radstock mines; 400 or 500 yards would be a satisfactory length, and about 6 ft. x 7 ft.; Brain, 5910-22. Perfectly satisfied as to the dangers of coal dust without further experiments, but would like to see experiments with coal dust, and the various kinds of explosives to ascertain to what extent the high explosives are flameless or will ignite coal dust; Hood, 6029-33. There could be no better test than to have some disused coal mine, or district of a coal mine, in which the actual conditions of a mine would be present; must be a mine free from gas ; McMurtrie, 6139-47. Is quite satisfied without further experiments; Thomas, 6289. Thinks it would be useful to have experiments with the different explosives by way of comparison; 6292-95. EXPERIMENTS WITH LAMPS AND DUST BY THE MINING AND MECHANICAL INSTITUTE OF NORTH STAFFORDSHIRE : Ashworth, 4638-42, 4704-12, 4733-43. EXPERIMENTS OF THE ACCIDENTS IN MINES COMMISSION WITH LAMPS: Ashworth, 4767-74. EXPERIMENTS OF SIR FREDERICK ABEL WITH COAL DUST: Ashworth, 4637. Witness is of opinion that Sir Frederick Abel's experiments at Wigan and Chatham prove that coal dust alone will not cause an explosion, but; where flame is given off by the firing of a shot of gunpowder, the flame would under certain conditions ignite the surrounding coal dust and would be considerably elongated as a consequence by the addition of the flame in the coal dust; Brain, 5773, 5786. TNDEX. EXPERIMENTS OF THE CHESTERFIELD AND DERBYSHIRE INSTITUTE: The velocity not sufficient; Ashworth, 4652. Thinks the apparatus was far too small to set up an explosion of dust; Forman, 5152; 5156-58. EXPERIMENTS WITH EXPLOSIVES BY THE NORTH OF ENGLAND INSTITUTE OF MINING ENGINEERS: The shape of the chamber; Ashworth, 4732. The chamber far too small for coal dust explosions; Forman, 5167-73. EXPERIMENTS BY Ms. HALL: No analogy between these experiments. and a coal mine ; Woods, 5187-88. Not a fair example of the conditions which prevail in a coal mine; McMurtrie, 6137-38. EXPERIMENTS BY MR. GALLOWAY: In the experiments at Dowlais he only obtained explosions with dust from the Rhondda Valley. Failed to obtain explosions with dust from the neighbouring collieries; H. W. Martin, 5355-60. Ignited dust with the flame from a blown-out shot; 5479-82. EXPERIMENTS-GERMAN: Witness thinks that these experiments have proved that coal dust alone will not cause an explosion, but where flame is given off by the firing of a shot of gunpowder, the flame would under certain conditions ignite the surrounding coal dust, and would be considerably elongated as a consequence by the addition of the flame in the coal dust; Brain., 5773. Thinks they proved that the utmost limit coal dust alone would carry a flame is 70 feet, and that coal dust alone was not to be considered dangerous and as causing explosions in mines; 5786-90. Accepts a correction as to the statement that coal dust would not carry an explosion further than 70 feet; 5825-36. Believes that the only experiment which gave an explosion of coal dust was that from the Pluto seam; McMurthie, 6136-38. EXPLOSIVES: Has had no practical experience with bellite, but believes it to be safe even with an insufficient quantity of stemming. There have been accidents with securite and roburite, but supposes they are absolutely safe if all the conditions are fulfilled; Ashworth, 4686. Proved that if the heat of the explosive is reduced, by the time it gets outside the hole, to less than 2,732 degrees Fahrenheit, the gas cannot be ignited ; 4627. The foregoing statement is taken from the report of the French Commission ; 4688, 4689. In the present state of knowledge all explosives should be protected; 4649, 4650. As liable to have an explosion with a high explosive, if it is not properly detonated, as with the best gunpowder ; 4629. Knows of no explosive which can be relied upon to give no flame. Has seen experiments with bellite and did not see any flame upon that occasion; Morgan, 4826, 4828, 4845. The flameless explosives not so effective as gunpowder; 4831. But safer, 4832. Not suitable for rock; 4834, 4835. Has not had much experience personally with these explosives, but the experience of the men points in this direction. The workmen consider roburite altogether ineffectual and object to the fumes it gives off; 4846-48, 4916-4924. A flameless explosive is an advantage if of the same strength as the ordinary powder; 4854. The flameless explosives are not much used in South Wales; 4915. Has seen large flame from dynamite; Isaac, 4992-94. Used it in rock; 4995. Fumes from dynamite worse than from gunpowder; 4996. Considers the high explosives to be much safer than gunpowder and as effective; Forman, 5086-90, 5100. Speaking for Durham thinks they are as handy as powder; 5091. Has seen experiments with roburite : states that there is sometimes a scintillation, but scarcely a flame; 5092-95. A Committee of inquiry arrived at the conclusion that though the flames of roburite were unpleasant they were not injurious; 5095. 5096. Could not say that roburite is absolutely safe; 5097, 5098. Roburite used at Hetton, and tonite at South Hetton, 5099. Some mines could not be worked without explosives, and even if it were thought advisable to prohibit the 99 EXPLOSIVES-continued. use of gunpowder, the prohibition should not extend to the high explosives; 5101, 5102. Gunpowder used in West Durham where there is very little gas; 5103-105. Very little gunpowder is used in East Durham; 5106-108. Thinks that some of the patent explosives might be used with perfect safety if under proper supervision; Woods, 5217. They are all liable to explode gas; 5302, 5320. Case in Lancashire in which a man is said to have been poisoned by the fumes from roburite; 5321-5323. Experiments by the Manchester Geological Society showed that there was a glare with roburite; 5324. The patent explosives safer than gunpowder but less effective; 5325. With regard to the prohibition of explosives, see Mr.Wood's evidence under " PRECAUTIONS." Does not think that any of the so-called flameless explosives are really flameless; H. W. Martin, 5443, 5447. Roburite shows less flame than the others; 5444. A most serious thing to the South Wales mines if explosives were entirely prohibited; 5445, 5446. Is using roburite and gelignite and as yet has had no complaints with regard to the fumes given off; 5496-99. Has been using ammonite for the last two or three years with gratifying results; has had no complaints from the shot firers of their having seen flame, and no complaints whatever about the fumes; ammonite is as strong as any of the high explosives-gelignite, dynamite, or any of themand witness prefers it to all others; Wilkinson, 5561-64. Has tried the compressed cartridge as used in Staffordshire with very gratifying results, but found it very expensive; 5565. Considers ammonite perfectly flameless according to his experience and the experiments he has made with it; 5583. The exclusion of explosives would increase the cost of working the mines with which witness is connected to the extent of a shilling per ton, or even more; 5623, 5624. None of the high explosives are used in the Forest of Dean; Brain, 5816. Certainly not necessary to prohibit gunpowder; 5815. Has tried all the so-called flameless explosives and prefers gelignite, if tamped with wet peat it is practically flameless; Hood, 5995, 6018-23. Would like to see experiments with explosives and coal dust in order to ascertain to what extent the high explosives are flameless, and whether they will ignite coal dust; 6030-33. Has experimented with all the patent flameless explosives and finds that they will not ignite dust; has tried in this way ammonite, bellite, and Ardeer powder; each show a little flash, but not continuous enough or strong enough to ignite the dust; the danger from blown-out shots would be materially reduced by the use of these explosives; Thomas, 6230-36. Knows of no explosive that is absolutely flameless; 6278. Does not think these patent explosives would fire the dust, but would not use them in the Welsh steam coal measures without watering; 6279-86, 6293. The high explosives may be objected to because they require special care in handling; Garthwaite, 6357, 6358. Perhaps to substitute them for gunpowder would entail an increase in cost-say one-third; 6359-67. Although not actually flameless, are much safer than gunpowder and should take its place; J. S. Martin, 6601, 6602. The extra expense would be trifling; 6603, 6632-40, 6651-55. See also under " BLASTIN," "BLOWN-OUT SHOTPS," " GUNrOWDER," " PRECAUTIONS," "WATER CARTRIDGE," "A AMMONITE," " BELLITE," " DYWNAMITE, " ARDEER POWDER," ROtRITE," and " TONITE." FIREDAMP: Believes all explosions are due to firedamp; Woods, 5201, 5305, 5311-5314. States that all the explosions of which he has any knowledge have been caused by gas; H. W. Martin, 5361. Refers to the explosion at the Pochin Pit, Tredegar: thinks it was initiated by gas, and aggravated and extended by dust; 5362, 5363. During an experience of fifty years in South Wales, does not know of a single colliery explosion that was not caused by gas; Bedlington, 6663, 5664. Gas is evolved from very fine coal dust; 5713. Is given off by coal dust, but more when it is fresh ; Thomas, 6276. 100 ROYAL COMMISSION ON EXPLOSIONS FROM COAL DUST FOREST OF DEAN COLLIERIES: Tratalgar Colliery, one of the largest mines in the Forest of Dean, employing about 750 men; Brain, 5755. This particular colliery is somewhat damp, and scarcely dry and dusty; 5841-47. Explosive gas has never been found in the Forest of Dean; Brain, 5760, 5863. Quite free from explosions either of gas or of dust; 5761, 5762, 5785, 5901. Some of the mines are dusty, and shot firing with gunpowder is largely practised; 5763, 5764. Occasionally there are blown-out shots, but witness has never known one to be followed by an explosion; 5765, 5766. Resolution passed by the Managers of the Somersetshire, Bristol, and Dean Forest Collieries, maintaining that the coal dust of the non-fiery seams of these districts will not per se cause an explosion, and has never been known to explode, and containing suggestions with regard to future experiments; 5799. Witness states that coal dust itself in the entire absence of gas-as is the case in these collieries-is not a sufficient explosive eleme nt to carry the flame to any appreciable extent ; 5794, 5854. Does not think it necessary to water the dust in the Forest; 5805, 5890. Would take no extra precautions against coal dust in this district; 5808, 5886. Does not think that any precautions are necessary with reference to shot firing, beyond those which are at present observed with regard to the proper placing of the shot; 5813, 5814. Certainly not necessary to prohibit gunpowder; 5815. Uses no flameless explosives; 5816. Powder cheaper than the other explosives, and under certain circumstances it may do its work better; 5817, 5818. Shot firing; 5848, 5849. The length of the flame from blown-out shots; 5857-59. Candles and lamps used; 5860. Does not find it necessary to put into force the provisions of the Mines Act with regard to dust; 5889. Unnecessary to clear away the dust before shot firing; 5891. Would not consider it a danger to set off more than one shot at a time; Brain, 5892-94. Refers to Mr. W. N. Atkinson's Report on the state of these collieries (see First Report, Appendix XI.), and inquires why, since some of these mines are reported as dry and dusty, and thoisands of gunpowder shots are fired annually, they have never had the slightest experience of an explosion; 5901-3, 5922. FRENCH COMMISSION: Recommendations with reference to stemming; Ashworth, 4632. Stated that if the heat of the explosive is reduced to 2.732 degrees Fahrenheit the gas will not be ignited by the flame; 4627, 4683. Witness understands that it.was proved that it was dangerous to fire a shot directly facing waste or gobbing; 4759. FORMAN, JoHN: President of the Durham Miners' Association; 5035. Gives his evidence as his own and not after consultation with his council; 5114, 5115. Has studied the question of explosions in mines and is of opinion that coal dust plays an important part in some of them ; 5036, 5037. To create or extend an explosion coal dust must be present in the immediate neighbourhood of a shot; 5038. The dust must be dry and fine; 5039. Knows from experience that there is flame from an Ordinary shot. An ordinary strong stone shot is equally as dangerous, if it is overcharged, as a blown-out shot; 5040, 5119-21. There must be a certain amount of concussion to throw the dust in the air; 5041. The dust may be ignited either by the flame from a blown-out shot, or by the flame from an overcharged shot. If a shot is overcharged it is almost certain to have flame; 5042-44. A large amount of dust required to produce an explosion; 5121, 5149. Having been ignited by a flame from a shot, the particles of dust, if finely divided and surrounded with air, ignite each other and generally extend, and the temperature rises to such a height that the dust explodes; 5045-47. The explosion may be carried on as long as there is dust to feed the flames; 5048. The quantity of coal dust in the air in the ordinary working of a pit is not sufficient to explode. It IN MINES: FORMAN, JOHN-continued. must be raised by a shot, and there must be a large quantity of fine dust adhering to the sides, timbers, and floor. There must be a quantity of dust floating in the air before it will ignite; 5050, 5051. The explosion may go with the air or against it. It depends upon where the ignition is and the track of the coal dust; 5052. Was for twelve months engaged in exploring Seaham Colliery after the great explosion in 1880. The disaster was due not to a blown-out, but an ordinary, shot; 5053-58. Impossible for gas to have been given off from the strata; 5154-55. The ventilation was too good to allow gas to be present; 5059, 5060. A coal dust explosion entirely; 5061. Describes an explosion at Seaham in 1871, and attributes it to dust; 5062, 5063. Examined the scene of the explosions at Trimdon Grange, Tudhoe, and Usworth. In all these cases, believes that dust was the prime agent, because the ventilation was so good that there could not possibly have been any gas. It is to be noted that the explosions followed the dust and avoided the damp; 5064-73. In all the explosions which are considered to be dust explosions no force is exhibited for about sixty to eighty yards on each side of the shot. The explosion gathers force as it goes. If in these cases gas had been the agent instead of dust, witness contends that the force would have been exhibited at once, or at any rate much quicker; 5074-76. Believes the 12th General Rule to be a good rule, but thinks that the 4th General Rule ought to be amended a little. In addition to reporting when gas is seen, it would be well if the Rule could be altered to require a report to be put on record where there is an accumulation of coal dust; 5077, 5078, 510913, 5138-40. Where there is any great quantity of dust it should be removed; 5079. Recommends watering, especially in the intake roads, or in places where there is an accumulation of dust 5080-82. It is not practicable to water the working-faces, but in general these are comparatively safe ; 5081, 5141. Thinks the General Rules are very good if properly carried out, with the addition named above to General Rule 4; 5083-85. Speaking as regards his own county of Durham, would prohibit gunpowder altogether. Considers it very dangerous and thinks the high explosives are safer. There may be a scintillation from roburite, but scarcely a flame. Thinks it gets the coal just as well as powder; 5086-94. A committee formed in Durham to examine into the question of the fumes given off by roburite decided that they were not injurious; 5095-96. Cannot say that roburite is absolutely safe where there is gas, but if gunpowder were prohibited he would not extend the prohibition to the high explosives; 5097-5102. Thinks some mines could not be worked without . some kind of explosives; 5102. Gunpowder is largely used in the western part of Durham, but very little is used in the eastern portion ; 5103-108. A damp place a few yards wide would arrest an explosion; 5116-18. The wedge is not much used in Durham. It answered very well, but it is very hard work, and the men prefer roburite ; 5122-29. The provision of the Mines Act, 1872, which enables the workmen to examine the collieries, is put into operation in Durham, but the examination extends only to the ventilation and the roof and not to the dust. The men would laugh if they were asked to examine for coal dust; 5130-36. Coal dust by itself is able to form an explosion without gas; and where there is a small quantity of gas the presence of coal dust very much stimulates and increases the power and danger of an explosion; 5137. Speaking for Durham, does not think that the rule with regard to the firing of shots in dry and dusty l)laces is carried out in the faces; .5142-49. Thinks the apparatus in the Chesterfield experiments was too small to obtain an explosion with dust in the absence of gas ; 5150-53, 5156-58. 101 INDEX. FORMAN, JoHN-continued. If experiments are carried out by this Commission, they should be made in a chamber not less than a quarter of a mile long. It should be about the size of a gallery in a mine, and should be on the surface ; 5159-62; 5167-73. Experiments in a disused mine would not be conclusive; 5163, 5174, 5175. GARFORTH, MR. W. E. : Microscopical examination of coal dust; Ashworth, 4637. GARSWOOD PARK COLLIERIES EXPLOSION: Nd trace of caked or burnt coal dust; quite unconsumed; Woods, 5195. GARTHWAITE, THoMAs YOUNG: General manager of the Camerton Colliery, near Radstock; 6296-98. Names the seams worked at this colliery; 6299304. Describes the state of the mine as regards ventilation, gas, and dust, the mode of working, and faults in the strata; 6305-19, 6350-53, 6373-90, 6404-13, 6421-29, 6441-46, 6453, 6462, 6486-88. The circumstances attending the explosion at the colliery on 13th November, 1893; 6320-49, 6391403, 6414, 6419, 6420, 6430-40, 6447-52, 6463-85, 6489-91. Recommends watering and the removal of the dust, and the substitution of a high explosive for gunpowder in the roadways; 6354-56, 6417, 6418, 6443. The objections to the use of high explosives; 6357-70. He is convinced of the truth of the coal dust theory ; 6371, 6372. Suggests the use of dust-tight waggons; 6415, 6416. GELIGNITE OR GELATINE DYNAMITE: Used at Apedale; in the habit of using a water cartridge with it, but omitted to use it with the shot which caused the explosion; Ashworth, 4697702. Used at the Dowlais Company's Collieries; 5442. No complaints about the fumes; has only recently adopted it; H. W. Martin, 5496-99. When tamped with wet peat it is practically flameless; Hood, 5995. Has seen a small flame from it with dry stone dust as tamping; 6018-23. GLAMORGAN COAL COMPANY'S COLLIERIES: Describes the precautions taken against dust; watering arrangements, shot firing, use of gelatine dynamite ; Hood, 5948-6039. GUNPOWDER: See Appendix XIV., handed in by Mr. Ashworth showing the effect of a blown-out shot of gunpowder upon the atmosphere; Ashworth, 4625, 4792-4802. These calculations are made to show that an atmosphere, which is not explosive in the ordinary way, becomes explosive by the addition of the ingredients arising from the blown-out shot; 4793. And also to prove that a powder of good quality, and of a certain density, may be fired by a detonator with almost perfect safety: 4626. Very difficult to get a blown-out shot with such a powder, but if a blown-out shot occurs "would not say that you " would not get somewhat of a disaster, because " you get a flame "; 4627. Stemming very important; 4629. Common black powder should not be used in dry and dusty mines, but only powder of the best quality; 4645. Density of powder an important consideration; 4677, 4678. "E.S.M." powder less likely to produce a blown-out shot than an ordinary black powder; 4679-83. In the present state of our knowledge would not use the "E.S.M." powder in a fiery mine unless it were further protected; 4684. Thinks it safe because the protective qualities are inseparable from the explosive itself; 4685. Witness uses it, but does not know where else it is employed; 4687, 4744. Always uses it in any place where there is any gas or risk whatever; 4745. No case of a blown-out shot with it; 4746. This is due principally to the composition of the powder; 4747. Composition of the " E.S.M." powder; 4789-91. E 82480* GUNPOWDER--continued. To forbid the use of gunpowder in South Wales mines would be a blow to the industry; Morgan, 4829, 4830, 4862-65. And would stop something like one-fourth of the collieries; 4833. Where watering is effectually done by sprays and the moisture carried in by the intake, gunpowder can be used with little or no risk in the South Wales pits; 4841-44. Gunpowder should be prohibited in places where there is dust and a danger of gas, providing an effectual and flameless explosive can be got; 4857-59. More powder is used in South Wales than is necessary; 4866-68, 4872, 4873. Would prohibit gunpowder in the county of Durham; thinks it very dangerous; believes the other explosives to be quite as effective as gunpowder and much safer; Forman, 5086-92. There will always be a danger of explosions so long as gunpowder, or any other kind of explosive is used in mines which give off a large quantity of gas; Woods, 5203. Has excluded gunpowder from the pits under his charge; Wilkinson, 5622. Largely used in the Forest of Dean, and would certainly not prohibit its use in this district; Brain, 5815. Cheaper than the high explosives, and under certain circumstances does the work better ; 5817, 5818. Does not use it in dusty mines; Hood, 5991. Experiments which he has made show that gunpowder and low explosives will ignite coal dust; Thomas, 6226-29. Should not be used in dusty places; Garthwaite, 6353-56, 6418, 6443. Should be entirely prohibited; J. S. Martin, 6601603, 6632-40, 6652. See also under " BLASTING," " BLOWN-OUT SHOTS," "EXELOSIVES," and " PRECAUTIONS." HAYDOCK EXPLOSION: In the Wood Pit; Ashworth, 4620. The gas present in the air, mixed with the coal dust, exploded at a Davy lamp; 4621, 4640. HIGH BROOK COLLIERIES EXPLOSION: The coal dust quite unburnt and unconsumed; Woods, 5196. HOOD, WILLIAM WALKER: General manager of the Glamorgan Coal Company; 5923. Believes that coal dust is inflammable without the presence of gas, other than that contained in itself; 5925. Explodes, or inflames, by simple contact with the heat; 5926, 5927. A candle has not sufficient flame to inflame or explode it; 5928. Coal dust will explode at the coke ovens; 5929, 5930. A blown-out shot would explode it, and the explosion once set up would be continued indefinitely as long as the dust exists; 5931-35. Believes that the explosion at Pen-y-Graig was initiated by gas and continued entirely by dust; 5936-40, 6002-10, 6035, 6036. Believes that the explosion at the National Colliery, in 1887, was a dust explosion, and that it was arrested by water on the roadways; 5941, 5942. Does not think it necessary to take any precautions beyond those in the General Rules; 5943-49, 6028. Thinks that if a space of twenty yards is watered round about where the shot is to be fired, it is not necessary to water all the roads except for the comfort of the men; 5950-52. Looks upon the compressed air system of damping as the best; 5953-60. Witness claims that he gets nearly the same result by the pressure of the water, without introducing the air; 5961-64. Explains his own system of watering with a spray, and describes its effect upon the atmosphere. Thinks that if such a system were adopted, no other precautions, beyond those already taken, would be necessary; 5965-90, 6011-17, 6037-39. Speaking of the mines under his charge, does not use gunpowder in dusty mines. Uses gelatine, and has seen flame from it; 5991-95, 6018-23. Has had the dust in the roads analysed to show the moisture in the coal, and the moisture in the dust after watering; 5996. O 102 ROYAL COMMISSION ON EXPLOSIONS FROM COAL .DUST IN MINES: IOOD, WILLIAM WALKER-continued. Describes the effect of dust put into coke ovens ; 59976002. Has seen a flame from a blown-out shot extend five or six feet; 6024-27. Would like to se'e experiments with coal dust, and the different kinds of explosives; 6029-33. Believes that coal dust will ignite at a torch, but the dust must be so thick that it would be impossible to live in such an atmosphere; 6034. HYDE EXPLOSION, January 18, 1889: Gas brought down by a fall of roof; Woods, 5258-62. ISAAC, THOMAs DARONWY : President of the Rhondda Valley Labour Association. Worked in the South Wales mines as a collier for nearly 30 years; 4934-38. Believes that" coal dust " will explode in itself when the air is very hot in " fiery mines," and will carry on an explosion; and therefore is a danger to be guarded against; 493942, 4958, 5021. With regard to precautions, believes that it is impracticable to water the dust at the working faces, and suggests that mines should be worked in smaller sections with a fresh current of air for each section ; 4943-46, 4951-55, 4977-91, 4997-5200. .Recommends removal of the dust, and the watering of the main roads by a patent watering tank; 4947-51. States that there is generally flame from a blown-out shot; 4956, 4957, 4966-75. Blown-out shots are generally due to undercharging; also to insufficient tamping and inexperience;. 4959-65, 5028-34. The system of watering adopted at Mardy is not sufficient to lay the dust in the faces; 4976-79. Has used dynamite in very strong rock. Has seen much flame from it. Its fumes are worse than those from gunpowder; 4992-96. Has seen the dust igniting in the gauze of his lamp: 5021-3. It is not his impression that any recent explosions in South Wales, say within the last 10 years, have been caused by coal dust alone; 5024, 5025. LAMPS: The explosion at Swaithe Main, Barnsley, was caused by a Stephenson lamp passing a mixture of firedamp and coal dust through the gauze; Ashworth, 4601-604. The explosion carried on by coal dust over the whole mine ; 4605-608. Refers to the explosion at the Wood Pit, Haydock, caused by a mixture of coal dust and gas exploding at a Davy lamp; 4620, 4621, 4640. Describes experiments at Harecastle with the Davy, Clanny, Williamson, Stephenson, and Gray, in an atmosphere charged with firedamp and coal dust; "4638, 4641, 4704-709. A Davy lamp in an atmosphere of coal dust and a small percentage of gas is unsafe; 4639, 4640. Thinks it necessary with every safety lamp, if the mine be dry and dusty, and giving out firedamp, unless the gauze is specially protected, that such lamp should have two gauzes. Mentions instances at Morfa Colliery, and Mossfields Colliery, where lamps have failed; 4642. In the former case it was a Marsaut with the gauze taken out, which reduced it to a Clanny; 4710-12. Various lamps described; 4733-43. Refers to the experiments of the Accidents in Mines Commission with lamps; 4767-74. For the lamps and lights at Dowlais Iron Company's Collieries, see under" DowLAIs." The prohibition of naked lights would increase the danger from falls of roof; H. W. Martin, 5411-13. Has tried an electric lamp; 5471-75. From practical experience is convinced that coal dust will not ignite at a lamp; it burns and inflames, but will not explode; Thomas, 6221-23. It makes very little difference if the dust is mixed with firedamp; 6224. LANCASHIRE COLLIERIES: The fiercest explosions have occurred in mines in which the ventilation has been the most perfect; Woods, 5190. Seams as hard as any in the country are being worked without any kind of explosive; 5206. Attributes the explosions that have taken place in Lancashire to gas, and states that the gas of the 9-feet seam is not easily perceived with the lamp, and so has escaped observation; 5191, 5192, LANCASHIRE COLLIERIES-continued. 5252, 5262. Describes the method of dealing with rock roofs and floors; 5231-37. The coal can be won without explosives; 5238. Precautions with regard to shot firing; 5219, 5220, 5241. A great many of the Lancashire explosions have occurred in the coal face either through blown-out shots or the reckless use of gunpowder; 5288-90. As a rule coal dust has been present in these cases; 5291. 'To stop shot firing altogether in the Lancashire district would fall very heavily on collieries working the hard seams (the 9-feet, for example), but does not think there would be any serious loss; 5309, 5310. The wedge is not used in Lancashire; 5315. Roburite largely employed, and witness refers to the case of a collier who is said to have been poisoned by it; 5321-24. LEYCETT EXPLOSION: Due to an atmosphere charged with coal dust and a small per-centage of firedamp exploding by means of a safety lamp; Ashworth, 4640. LIME CARTRIDGE: Not effective in hard ground; Morgan, 4831, 4834. Lime tried in Wales 40 years ago, but without the mixture of chemicals with it; 4908-10. Where the coal is friable it did more harm than good, but where the coal was hard it worked very well; Wilkinson, 5565. LLANERCH EXPLOSION: Due to a small explosion of gas carried on by dust; mainly a dust explosion; Ashworth, 4623. LUDLOW'S PIT, EXPLOSION AT: See the case of the blown-out shot under " RADSTOCK COLLIERIES." MALAGO EXPLOSION: An explosion of fire-damp in which dust played a very large part: JT. Martin, 6718-22. S. See .Professor Dixon's notes, Appendix XXI. MARDY COLLIERY EXPLOSION: Believes that coal dust intensified the explosion; Isaac, 5025. MARTIN, HENRY WILLIAM : Mining engineer, Vice-President of the South Wales Institute of Engineers; a member of the Monmouthshire and South Wales Coal Owners' Association ; and general manager for the Dowlais Iron Company's Collieries of South Wales, 5329-31. Had an experience extending over 30 years in the management of collieries and iron-stone mines in the Aberdare district, the Merthyr district, the Durham district, and in Japan, 5333, 5334. The Dowlais Collieries work steam coals and bitumi. nous Qoals, and are not what are called dusty mines ; 5335, 5336, 5345, 5417-19, 5512. The Evan Thomas' Bonnetted Clanny is used in some of the collieries, and naked lights in others; 5337, 5420. Shot firing is very largely employed; 5338, 5339. All the mines are subject to fire-damp except the bituminous collieries. Gas has never been seen in these; 5340. Naked lights are used in the steam collieries in which there is fire-damp, and in which precautions are taken against dust by watering, but not where the dust is considered dangerous, 5341, 5342, 54205437, 5519-24. There have been several slight explosions in the steam coal collieries, but none whatever in the bituminous; 5343, 5344, 5513-16. Thinks that coal dust aggravates explosions initiated by fire-damp; 5347-48. The presence of coal dust increases the liability of fire-damp to explode; 5349. Does not think that coal dust alone, in the absence of fire-damp, would cause an explosion under the ordinary conditions of a mine; 5350, 5476, 5501. The thin seams of coal in South Wales are worked by longwall, but there is a great deal of roof ripping and bottom cutting, which produces shale and stone dust, and renders the coal dust less liable to burn or inflame; 5351-53, 5517, 5518. Considers the damping of the dust to be the chief means of preventing the extension of explosions; 5354. INDEX. MARTIN, HENRY WILLIAM-continued. Believes that the quality of the dust varies in different mines, and that some might be more inflammable than others. Refers to Mr. Galloway's experiments with different dusts; 5355-60, 5479-82. Considers that the explosions of which he has any knowledge have been caused by fire-damp alone; 5361-63. Would not trust dust at all under any conditions, even when mixed with shale and stone dust, without damping it. Thinks dust a danger to be guarded against ; 5364-70. The dust should, as far as possible, be removed from the main roads, and damping should be carried on in the main roads, where dust is the most dangerous; 5371-74, 5495. Explains the system of damping which has been used in three of the Dowlais collieries since 1886, and which consists of compressed air and water; 5375-85, 5390-410, 5448-70, 5505-511. By this system he claims that the dust is absolutely damped, but the removal of the dust is not thereby rendered unnecessary, 5386-89. Believes that an explosion from coal dust is impossible with this system; 5403, 5404. Thinks the danger from explosions, due to the use of naked lights in a colliery such as they have in South Wales, is not so great as would be the danger from falls of roof due to the want of a better light if naked lights were forbidden; 5411-13. Thinks the spray system of watering could be adopted without the risk of dam, ging floor or roof ; 5414-16. Explosives are used in the Dowlais collieries on a very large scale. Dynamite, powder, roburite, and gelignite. Believes that roburite shows less flame than the others, but is of the opinion that none of the high explosives are flameless; 5438-44, 5417, 5496-99. It would be a very serious thing to have explbsives entirely done away with in the mines under his superintendence, 5445. Has tried a new electric lamp; 5471-75. Speaking with regard to his own collieries, the workmen do not largely avail themselves of the 39th General Rule of the Mines' Inspection Act to examine the mines ; 5477, 5478. bas never known a blown-out shot to ignite dust in the absence of gas, and thinks it impossible; 5483-88. Would prohibit the firing of more than one shot underground at the same place, and at the same time, to prevent the risk of an inflammation of the dust, but does not think that such an inflammation could cause an explosion in the absence of gas; 5489-94. Has come to this conclusion owing to the explosion at Altefts, which was consequent on the firing of three shots; 5533. Thinks the practice of damping, as provided by the Mines Act, is pretty generally observed in South Wales ; 5525. Believes Altofts explosion was caused by gas; 5526-34. MARTIN, JOSEPH SAMUEL: Her Majesty's Inspector of Mines for the SouthWestern District, 6569-71. Believes that coal dust alone may cause an explosion; 6572-75, 6600. Is of the opinion that the explosions in Ludlow's Pit, Radstock, November 1891, and the New Pit, Camerton Colliery, were entirely due to dust; 6576-80. Has had experience of a colliery explosion in Westphalia, 6597. Gives evidence with regard to the Camerton explosion; 6581-99, 6612-31, 6657-59, 6671-717. Recommends the entire prohibition of gunpowder and the substitution of a high explosive; 6600-604, 663240, 6648-55. Thinks watering is desirable and necessary, but not totally.effective ; 6605, 6606, 6641-47. Is of the opinion that shot-firing should be done by electricity and when the number of men in the mine is reduced to a minimum; 6607-11, 6656, 6662-67. Watering in the South-Western District; 6660, 6661, 6668-70. Believes that the Malago explosion was a fire-damp explosion extended by dust; 6718-22. E 824 80. 103, McMURTRIE, J. : A mining engineer; past President of the South Wales Institute of Civil Engineers; has been managing the Radstock collieries, the property of the late (Countess Waldegrave and her trustees, for learly thirty years; 6040-44. Describes the Radstock collieries. Entirely free from fire-damp; worked by longwall; produce a hard coal; two distinct groups of seams-the upper group called the Radstock, and the second group, or Farrington series; the dust for the most part pure coal dust, but with a certain amount of shale dust mixed with it; 6045-53. Refers to Mr. W. N. Atkinson's report on the Rad. stock Collieries which appears in Appendix XI. of the First Report; 6053-55. During the whole time that he has known these pits there has never been any explosion whatever, and blasting has been going on continually. About 20,000 shots are fired annually in the four pits under his charge; 6056, 6057, 6064-66. When blasting, no precautions whatever are takenno removal of dust and no watering; 6058-61. Would describe the seams of the upper, or Radstock, series, as being not generally dry and dusty, but there are occasional engine planes and horseroads which are dry and dusty; 6062, 6063. In this series has never heard of a case-either in his own pits, or in any of the pits in the district-of flame from a blown-out shot being extended by the dust, still less of an explosion; 6067-69. Would call the seams of the Farrington series moderately dry and dusty. These seams are described by Mr. W. N. Atkinson as the driest workings in the Bristol and Somerset coalfields, the dust of which appears to be pure enough to be capable of causing an explosion if raised and ignited; 6055, 6070-73. Witness considers the Farrington seams to be more dry and dusty than the seams in the Forest of Dean, but on the whole not so dry and dusty as the South Wales seams, or the steam coal seams in the Rhondda Valley, 6074, 6075. Since opening these seams of the Farrington series 15,000 shots have been fired-chiefly in the roads and not in the coal; 6076-80. Describes a blown-shot in the middle pit in the lower, or Farrington, series. &n extremely heavy shot in the stone; the charge consisted of' 30 ounces of compressed powder; the seam at the point of firing was not dry or dusty; the place generally damp; the dust rather wet; the effects of the shot were felt at a distance of 300 yards away; blew out lights in that part of the pit; opened doors; reversed the ventilation for a few minutes; the effect was not confined to that part of the pit, but was felt at a point 154 fathoms higher up in the upper group of seams; 6081-6104, 6187-89. Describes the case of a blown-out shot at the Ludlow pit, also in the Farrington, or lower group of seams. The charge consisted of eight ounces of powder; the props were charred at a distance of eight yards from the shot; the mine dry and dusty; the dust was not confined to the mere point where the explosion occurred, but extended under precisely the same conditions to the further end of the pit; would call it an inflammation, not an explosion; a man was burned at a place 80 feet from the shot; the effects felt by a man 124 feet away; 6105-30; 6151-78; 6182-86; 6190. In the above two cases, witness is of opinion that the coal dust had the effect of extending the flame, but only for a limited distance; 6128-29, 6177; and thinks coal dust contributed to the force; 6130. Believes that coal dust alone will not produce an explosion, and that although it may increase the effects of an explosion it will not do so to any dangerous. extent; 6131-32. Considers that the present Mines Act provides sufficient precautions. It has not been considered necessary to put into force in the collieries under his charge the coal dust provisions contained in the Act; 6133, 6134, 6179-81. Alludes to the German experiments, and to Mr. Hall's experiments. Does not regard the latter as representing the state of things in a coal mine; 6135-38. Recommends that future experiments should be made in a disused coal-pit; 6139-45. Believes it to be conclusively proved that ordinary shot-firing in coal dust will not either cause a P 104 ROYAL COMMISSION ON EXPLOSIONS McMURTRIE, J.-continued. lengthened flame or an explosion in a coal mine. Speaks more particularly with regard to his own experience, and the class of dust in the mines that he has had to deal with. Would rather not express an opinion upon dust such as that which is found in the Rhondda Valley; 6146-50. MICROSCOPICAL DUST: Ashworth, 4688. EXAMINATION OF COAL MORFA COLLIERY EXPLOSION: Failure of a lamp; Ashworth, 4642. The explosion probably caused by gas from a goaf; 4712. The explosion arrested by a damp space of 70 yards; 4713. MORGAN, DAVID: Agent for the Aberdare and Merthyr Miners' Association, representing 8,500 men; 4810, 4811. Gives evidence entirely on his own account and not after consultation with his association; 4869-71. For 35 years worked in mines in South Wales which are fiery and dusty; 4812-15. Believes that coal dust cannot be ignited by a naked light, or by the flame from a blown-out shot; but, if there should be an explosion of gas, is of opinion that the dust is kindled and plays great havoc, and that the explosion is carried to greater distances by the aid of dust; 4816-19, 4855, 4856, 4925-27. The presence of coal dust is therefore a source of increased danger; 4820 4821. By way of precaution recommends watering by sprays as practised in South Wales, but, even when this is done, it is still necessary to remove the dust till it is no more than a thin covering; 4822-25, 483944, 4857, 4897-4904. Very desirable to get explosives which give no flame, but knows none which can be relied on in this respect; 4826-28, 4857-59, 4906. Powder is much used in South Wales. To prohibit powder entirely would close one-fourth of the collieries in this district; 4829-30, 4862-65. The so-called flameless explosives, such as bellite, are not so powerful as powder, and are objected to by the men because they give off fumes, and are not effectual in rock; 4831-35, 4845-48, 4915-24. Water cartridges are used in Wales, but witness has no experience of them; 4836, 4837. :In the majority of cases believes that blown-out shots give off no flame; 4817, 4849-52, 4890-96. Inhot, dusty places, where there is any danger of gas, shot-firing should be prohibited unless a flameless explosive can be found; 4853, 4854. Believes the law sufficient as it stands if carried out; 4860, 4861, 4905. Thinks that powder may be used rather too extensively in South Wales; 4866-68, 4872, 4873. Before shot-firing neither the hole which has been bored, nor the quantity of the charge, is examined by the man whose duty it is to fire the shot; 4874- 80. 'I'o adopt this course would reduce the number of accidents, but it would involve the employment of too many men, and the cost would be too serious; 4881-83. Thinks the better plan would be to provide some specific training for the men, instead of leaving them to pick up their skill in a haphazard way; 4884-89. The workmen in South Wales do not, as a rule, avail themselves of the provision of the Mines Act, which allows them to examine the mine themselves ; but, when this inspection does take place, observation is directed rather to the ventilation than to coal dust; 4928-33. MOSSFIELDS : The failure of a lamp; Ashworth, 4642. NAKED LIGHTS: See under " CoAL DUST AND NAKED LAMPrs. " LIGHTS," and NATIONAL COLLIERY EXPLOSION: Dust undoubtedly played a part, but gas may have been present; an Abel's envelope used without the water; Wilkinson, 5568, 5569. The effect of damp places on the explosion; 5579, 5580. FROM COAL DUST IN MINES: NATIONAL COLLIERY EXPLOSION-continued. A dust explosion: the spread of the explosion stopped by water on the roadways at the bottom of the downcast, and also at the bottom of the upcast shafts; Hood, 5941. Caused by the careless use of a water cartridge; J. S. Martin, 6655. PARK SLIP COLLIERY, TONDU: See Professor Dixon's Report, Appendix XXI. PEN-Y-GRAIG, oa NAVAL COLLIERY EXPLOSION: A very dry and dusty mine: the explosion caused by a gunpowder shot igniting gas which fired the dust and carried the flame into the other portion of the colliery; the explosion fiercer on the main travelling roads where the areas were greater and the dust finer; the continuance of the explosion not to be accounted for by gas on account of the perfect ventilation; if a blower of gas had been the cause he would have expected to see some trace of it afterwards; Hood, 5937, 5940, 6002-10, 6035, 6036. PRECAUTIONS: Recommends the removal of the (lust and the maintenance of thoroughly wet patches at intervals on the roads; Ashworth, 4643, 4644, 4713, 4715, 4717. Wet patches would only reduce the extent of an explosion; 4718. Every explosive should be used in a hole of reduced diameter in proportion as it is stronger than gunpowder; 4630-33, 4645. This is not an invariable practice; 4695, 4696, 4700, 4703. Explosives should not be used in any case where there are ropes, chains, rails, or signal wires anywhere in the line of fire, as the heat of the explosive blowing out across these ropes, chains, &c., sets up an electrical condition which disturbs the dust all along the roads; 4634-36. In every dry and dusty mine giving out fire-damp, every lamp, unless its gauze is specially protected, should have two gauzes; 4642. No shot should face a strong current of air; 4646, 4720. This applies specially to the main roadways, not to the working faces; 4759, 4765. Shots should always be fired electrically; 4647, 4725. The question of leverage-that is the length of the charge--is most important; 4648, 4691-94, 4784-86. It should be compulsQry for the fireman to see the shot hole before it is charged, and to superintend the charging; 4662, 4726, 4727, 4758. Recommends the removal of the dust as far as practicable, and also watering; Morgan, 4822-25, 4839-44, 4857. Shot firing--except with an explosive which will not give a flame-should be prohibited in hot places where there is dust and a danger of gas; 4853, 4857. Would dispense with gunpowder in such places if a flameless and effectual explosive can be obtained; 4858, 4859. The law with regard to shot firing is sufficient as it stands; 4860-62. Scarcely possible to remove the dust so clean that it would not be' necessary to water; 4897. Attaches the most importance to the watering; 4898-4900. Thinks no further precautions are necessary as far as dust is concerned, but believes that explosives may be improved; 4905, 4906. Watering a practicable precaution; Isaac, 4943. Not possible to water at the working face, and suggests that a mine should be worked in smaller sections with a separate current of air for each section; 4943-45, 4949-55, 4997, 5010-20. It would add to the expense to make such an alteration in an old, well developed colliery, but when a mine is opened upon this system the expense would not be material; 4946. In further evidence modifies the two preceding statements ; 4980-91. Recommends the removal of the dust and the watering of the main travelling roads with a patent watering tank; 4947-51, 5027. Has seen the system of watering at Mardy Colliery where the water is under pressure and distributed in the form of sprays in the in-take; does not consider that the atmosphere in the intake isdsufficiently saturated with moisture to lay the dust in the faces; 4976-79. The Twelfth General Rule is a good rule, but the Fourth General Rule should be amended so as to require a report to be put on record when there is an accumulation of coal dust, as is at present the case with regard to gas; Forman, 5077, 5078, 5083-85, 5109-11, 5138-40. The dust should be 105 INDEX. PRECAUTION S-continued. removed; watering should be done especially in the intakes, and in any place where there is an accunmulation of dust; 5079-82. The working face is comparatively safe and it is not practicable to water there; 5081. In special places the dust at the working face might be dangerous; 5142-43. Would prohibit gunpowder in the county of Durham; 5086-93. Believes that the Twelfth General Rule-speaking with reference to Durham -is not strictly carried out in the working face; 5144-48. Shot firing--no matter what kind of explosive is used, whether it be gunpowder, roburite, tonite, dynamite, or any of the other patent explosives-should be prohibited in mines which give off a large quantity of gas; Woods, 5903. Limits this to collieries where there is a liability to an irruption of gas ; 5230, 5303-305. Knows of nothing to take the place of explosives except the wedge, and thinks it could be employed in all coal mines; 5204-6. To prohibit the use of explosives would of course increase the cost of working, but not very much, and witness does not think it would cause any mine to be closed; 5207-11, 5225-29, 5306-308. It would come very heavy on the hard seams; 5309-10. An exception might be made in the case of rock, and in pits where it was impossible to work without explosives: some of the patent explosives if under proper supervision, and at the proper time, might be used with perfect safety; 5216-19, 5239, 5240. There might be greater freedom in open light collieries, but witness's opinion is that no mine is safe from an irruption of gas; 5220-24. Nothing to suggest with regard to what is the common practice of not firing shots when there are not many men in the pit; 5241. If shot firing continues to be allowed in fiery seams, urges that the Mines Act should be literally carried out; 5242, 5243. If it is properly carried out, he has nothing further to suggest; 5244-46, 5300-302. Would not trusi coal dust at all under any conditions, even when impure and mixed with shale or stone dust, without damping it; H. W. Martin, 5366-70. States that the dust should as far as possible be removed from the main roads, and that damping should be carried on in the main roads ; 5371-73. Not absolutely necessary to damp at the faces; 5374. For the system of watering with a spray obtained by means of compressed air see Mr. H. W. Martin's evidence under " WATERING." PRECAUTIONS-continued. every part of a heading where it lodges in the crevices and timber; 5695. Thinks that what danger there is is amply met by the present law; Brain, 5801-18. Speaking for the Forest of Dean, does not consider watering is necessary, and thinks extra precautions in this district superfluous: certainly there is no need to prohibit gunpowder; 5883-94. Does not consider it necessary to take any additional precautions beyond those which are indicated in the General Rules; Hood, 5943-49. Thinks that if a space of 20 yards is watered round about where a shot is to be fired, it is not necessary to water all the roads: he does, however, water the roads for the comfort of the men in the mine; 5950-52. Impracticable to remove the dust: 5951. : o precautions, when shot firing, are necessary beyond those which are already taken; 5990. If the present Mines Act is carried out thoroughly, thinks nothing else is required; 6028. No further precautions are needed in the Radstock district beyond those contained in the present Act; McMurtrie, 6133, 6134. Recommends the use of flameless explosives: the tamping of the high explosives should be with a damp and non-combustible material. Advocates the prohibition of explosives of the gunpowder class and recommends watering ; Thomas, 6239-51. Since the explosion in the New Pit, Camerton Colliery, the witness will carry out all the rules as to dry and dusty mines, and should consider it necessary to use a high explosive instead of gunpowder in the roadways; but considers that gunpowder may be safely used in the working faces; Garthwaite, 6353-56, 6418, 6443. The use of dust-tight waggons recommended; 6415, 6416. Recommends the entire prohibition of gunpowder throughout every mine, and the substitution of a high explosive; J. S. Martin, 6601-604, 6632-40. Watering is a necessary precaution, but is not totally effective; 6605, 6606, 6643-47. During shot-firing the number of persons in a mine should be reduced to a minimum, and the firing should be done by electricity instead of by a fuse; 6607-11, 6653, 6656, 6662-67. See also under, " BLASTING," " EXPLOSIVES," " WATERING," " REMOVAL OP THE DusT," " LAMPS,' "ROBURITE," " SECURITE," " TONITE," " BELLITE," " DEER POWDER," and " AMMONITE." AR- Watering does not dispense with the necessity of removing the dust; 5388, 5495, 5509-11. No additional precautions are required with regard to the use of lights; 5412. The danger of an explosion arising from the use of a naked light is not so great as the danger, where safety lamps are employed, of falls of roof; 5412, 5413. A most serious thing if explosives were done away with in the South Wales mines; 5445. Suggests that a clause should be added to the General Rules to prohibit the firing of more than one shot in the same place and at thb same time, because one shot may raise the dust and the other inflame it, although he does not believe that this could possibly cause an explosion; 5489-94, 5533. Necessary to thoroughly water the ways and to saturate the atmosphere : WilkiLnson, 5551. Also to use an explosive as nearly flameless as possible; 5559, 5560. Practically no danger from coal dust if a flameless explosive like ammonite were used and the air of the mine kept saturated; 5567. Necessary to remove the dust to a thin surface; 5567. The duty of reporting on accumulations of dust when they exist could not be left, in witness's opinion, to a fireman, or indeed to any individual; 5592-94. To prohibit the use of explosives in the mines under his charge would increase the cost of working by ls. per ton, or even more; 5623, 5624. With ammonite, r :n explosive that was absolutely flameless, would sill think it necessary to take precautions with regard to dust as a matter of additional safety, and for sanitary reasons; 5625-28. Does not think the precautions of the Mines Act against dust are really necessary, because in a very long experience he has never seen any ill-effects from coal dust; Bedlington, 5672-74. Does not consider the removal of the dust necessary except from a sanitary point of view ; 5675, 5676. Thinks it advisable to use flameless explosives as a precaution against gas, but not as a precaution against dust ; 5677-82, 5695. Difficult tc remove dust in RADSTOCK DISTRICT: Refers to an explosion with a blown-out shot at the Ludlow Colliery, No. 4 pit: believes it to be a dusty pit: the mine not fiery where the accident occurred; Brain, 5767-71, 5837-40. Would hardly call it an explosion, but rather a prolongation of the flame from a blown-out shot, and, taking that view of it, it is strongly confirmatory of his opinion, that coal dust, such as is found there, would not cause an explosion; 5772, 5800. The place where the shot was fired was dry and dusty : the flame from it appears to have ignited the dust immediately surrounding the place, and the flame was carried some few yards along the face of the coal: but only a few yards, although there was abundance of coal dust for hundreds of yards further on: if the coal dust had been sufficiently dangerous to give off an explosion, witness is at a loss to know why the flame was not carried on more than a few yards; 5774. Generally speaking the flame from a blownout shot carries from 4 to 6 feet: in the present instance a man was burnt at a distance of 30 yards; 5775-77. No dampness whatever where the flame stopped, but an abundance of dry dust; 5778. The accident occurred not in a roadway, but in a new coal face being moved forward, and, therefore, the dust would be quite fresh, and would not be as fine as it is in the roadways; the dust exactly similar in character from the point of ignition to the point where the explosion ceased: fails to see why, if the coal dust was sufficiently fine to carry the flame 30 or 40 yards it should not carry it 100 or 150 yards, provided the coal dust theory is correct; 5779-94, 5854, 5855. Use partly lamps, and partly open lights; Brain, 5861. Gas in some of the measures; 5862, 5906. Further particulars with regard to the explosion at Ludlow's Colliery-the position of the shot, direction of current, &c.; Brain. 5864-82. P2 106 ROYAL COMMISSION ON EXPLOSIONS FROM RADSTOCK DISTRICT-continued. The Radstock Collieries consist of four working pits, and employ nearly 900 men: two distinct groups of seams--the upper group called the Radstock, which consists of six workable seams ranging from one foot to 2 feet 4 inches in workable thickness: the second group, or Farrington series consists of about six seams of about the same thickness, or perhaps slightly thicker; McMurtrie, 6043-45. The upper, or Radstock group, has been worked for a hundred years and there are no indications of fire-damp whatever: during the whole of this period so far as there is any record-and certainly within the 30 years that witness has known the district-there is not a single instance of gas having been found in the seams: longwail system of working: the coal very hard and compact: would not call them dry and dusty mines: but there are districts here and there where the strata are very dry and where there is a small amount of dust: the dust for the most part is pure, but there is a certain amount of shale dust mixed with it; 6046-55. Has never known an explosion in these mines; 6056. Blasting has been going on contirually without any precautions such as removing the dust and watering; 6057-63. Fire 20,000 shots annually; 6064-66. Has never known a case in the pits working the Radstock series (15 mines in all) where there has been a lengthened flame-far less an explosion-as the result of a blown-out shot; 6067-69. The Farrington, or lower group of seams, have been at work for about 50 years; the coal is more friable than the coal of the upper series, and may be called moderately dry and dusty; Mr. W. N. Atkinson, in his report on these collieries (see Appendix XI., First Report), says that the dust in this series appears pure enough to be capable of causing an explosion if raised and ignited. Witness thinks these seams decidedly more dry and dusty than the Forest of Dean seams, but not so dry and dusty as the scams in South Wales, or the steam coal seams of the Rhondda Valley; lMcifurltrie, 6070-75. They contain no trace o f gas; 6168-70. Have fired about 15,000 shots in these seams since beginning to work them about six years ago; witness's attention has been called to two blown-out shots; the blasting has been chiefly in the roads; 6076-80. Describes the case of a blown-out shot in the Middle Pit in the Farrington series; an exceptionally heavy charge of 30 ounces of compressed powder; a very great concussion; the explosion wholly due to the powder; the seam at the point of firing not dry or dusty; the dust rather wet; the effects of the explosion felt at a distance of 300 yards away; it also blew out lights, opened doors, and reversed the ventilation for a few minutes; the explosion not confined to the one part of the pit, but took effect at a point 154 fathoms higher up in the upper group of seams where the concussion was distinctly felt, and some doors were partially opened; McMurtrie, 6081-88, 6187-89. Believes that these effects were produced by the gunpowder alone, 60896104. D)escribes the case of a blown-out shot in Ludlow Pit, and in the same series of seams, i.e., Farrington; a charge of 8 ounces; an unskilful shot; the seam dry and dusty; the flame, as shown by the charring of the props, extended for a distance of 8 yards from the shot; opened doors at various places; a sman slightly burned at a distance of 80 feet; its effects felt by a man 124 feet away; believes coal dust had the effect of extending the flame but only for a limited distance; thinks that the coal dust contributed to the force of the explosion: it no doubt lengthened the flame and added to the force ; McMurtrie, 6105-32, 6151-78, 6190. Takes exception to the word " explosion "; cannot regard it as anything beyond a lengthened flame ; 6168. No trace of gas 6169, 6170, 6182-85. The workmen did not regard it as an explosion; 6171, 6172. His experience in connexion with the working of these seams shows, in his opinion, that coal dust will not produce an explosion, and that although it may increase the effects of anu explosion it will not do so to any dangerous extent; 6132. Witness's evidence applies exclusively to these and to similar mines; considers that the nresent Mines Act provides sufficiently for all dangers; he, as manager of the mine, and the Government In- COAL DUST IN MINES : RADSTOCK DISTRICT-continued. spector, have not considered it necessary to put into force the coal dust provisions of the Act ; 6133, 6134, 6179-81, 6186. The explosion in Ludlow's Pit was one of the explosions which led Mr. J. S. Martin to alter his views and to believe that coal dust per se is capable of causing an explosion.. Regards it as an extension of flame due to dust; J. S. Martin, 6574-77. See Appendix XXI. for Professor Dixon's Report on the Explosion in Ludlow's Pit. REMOVAL OF THE DUST: Great care is taken in Durham to remove the dust; Forman, 5112, 5113. See also under " PRECAUTION." RISCA EXPLOSION, JANUARY 15, 1882: Caused by a blown-out shot in the main intake, killinoe four men and 60 horses; Wilkinson. 553739. Dust raised in the air by two shots and fired by a third shot which had hung fire; no gas whatever ; the roadway in a stone drift, and the point where the explosion was initiated was only two or three hundred yards from the bottom of the shaft; 5540-48, 5571-78, 5595-601. The effect of damp places; 5581, 5582. Does not see how there could have been much dust to explode; Bedlington, 5711. ROBURITE : Said to be absolutely safe, but there have been accidents with it; Ashworth, 4686. Objected to in South Wales because it is not so effective as powder, and gives off fumes; Morgan, 4846-48, 4916-24. There is a scintillation from roburite, but scarcely a flame; a committee formed in Durham examined into the question of the fumes, and found that although unpleasant they were not injurious; F'orman, 5093-97. Cannot say that it is absolutely safe in gas; 5098 Used at Hetton; 5099. A workman in LancasLire is said to have been poisoned by it; Woods, 5320-24. Shows less flame thair the other high explosives; H. W. Martin, 5444. SEAHAM EXPLOSION, 1880: Witness engaged for 12 months in the mine as an explorer; Forman, 5053-55. A dust explosion entirely ; caused by an ordinary shot-not a blownout shot -in the stone; 5056-58, 5061, 5069, 5070. The ventilation would prevent any accumulation of gas; 5059, 5060. Precautions are now taken against dust; 5084, 5085. Cannot conceive where gas could have come from; 5153. Never known gas in the rock in Durham, and cannot believe that gas was in the roof; 5153-55. Describes an explosion at Seaham in 1871, which, he believes, was a dust explosion; Forman, 5062, 5063. SECURITE: Said to be absolutely safe, but there have been acci- dents with it; Ashworth, 4686. SHERIFF PIT, SILVERDALE: The case of a blown-out shot in 1878; Ashworth, 4609. Believes that it was due to the absence of ropes, chains, &c. that electrical conditions were not set up to disturb the dust and so prolong the explosion, 4676. SLADDERHILL EXPLOSION: See under " APEDALE,." SOMERSET, BRISTOL, AND DEAN FOREST COLLIERIES: A resolution from a meeting of colliery managers in this district, with respect to Mr. W. N. Atkinson's report on these mines (see Appendix XI., First Report). The resolution affirms that the dust in the non-fiery seams of this district will not, per se, cause an explosion, and has never been known to cause an explosion. It also contains recommendations with regard to experiments; Brain, 5795-800, 5910-22. It is to be noted that this resolution refers only to the non-fiery seams; 5904-909. SOUTH WALES DISTRICT: These mines are fiery and the majority dusty; Morgan, 4814, 4815. To restrict gunpowder in these collieries to the hard ground, and to forbid its use 107 INDEX. SOUTH WALES DISTRICT-cotinued. in the actual coal getting, would be a blow to the industry; 4829, 4830. And would stop about one fourth of the collieries; 4833, 4863. To forbid the use of gunpowder for the a- 4 ,ual coal getting would increase the cost of produc ion by something like 6d. per ton; 4865, 4866. More powder used than is necessary; 4867-73. The provision of the Mines Act, which enables the workmen to examine the mine from time to time, is taken advantage of in South Wales, but not as a rule. When such examination is made, observation is directed rather to the general ventilation of the mine, &c., than to coal dust; 4928-33. Knows of no explosion in South Wales within the last 10 years caused by coal dust alone; Isaac, 5024. The thin seams in South Wales are worked by longwall, but there is a great deal of roof ripping and and bottom cutting, which produces shale and stone dust; mixed with this shale and stone dust; the coal dust is less liable to burn or inflame; this partly accounts for the non-liability to explosions of coal dust in Welsh mines; H. W. Martin, 5351 -54. The quality of the coal dust differs in various mines, and some might be expected to be more inflammable than others; 5355, 5356. Refers to Mr. Galloway's experiments, in which the only dust which would cause an explosion was from the Rhondda Valley; 5355-60, 5479. For the system of watering adopted by the Dowlais Iron Company's Collieries, see Mr. Martin's evidence under " WATERING." The Plymouth Iron Company's Collieries in the Nferthyr Valley adopt the spray system of watering ; it is also employed in the collieries of the Powell Deefryn in the Aberdare Valleys; H. W. Martin., 5405, 5406. The practice of damping as provided by the Mines Act is pretty generally ob-erved, 5525. A most serious thing if explosives were done away with in South Wales; 5445. Risca Colliery, Abercarn Colliery, the National Colliery, and North Dunraven Colliery, described as very dry and gaseous; Wilkinson, 5535, 5536. Ammonite used with gratifying results; has used many special apparatus in blasting; 5561-65 Several very heavy outbursts of gas in South Wales; 5570. Explosives not used in the actual coal getting, but only in the roof; 5583-90. Impossible to carry on the collieries of South Wales at a profit without using explosives; 5591. Since the explosion at Risca has never fired a shot in that seam, but would not consider it at all dangerous to use ammonite there; 5602-605. To prohibit the use of explosives in the mines under his charge would increase the cost of working by a shilling per ton, or even more; 5623. Describes the use of the long feather wedge; it answers very well, but is not much used on account of the slowness and expense of the process; 5630-43. Nearly all the deep mines are dry and dusty; Bedlington, 5696-98. Does not water the dust; prefers to remove it; water softens the strata in the roads; 5699-5704. Uses a variety of explosives; 5705, 5706. The mines of which he has had experience are deep, dry, dusty, and fiery; 5746-48. Removes the dust in the roads, and wherever safety lamps are used has regard to the watering in the vicinity of the shot and the place where the shot is to be fired; 5749. The precautions taken with regard to coal dust; shot firing; the use of gelignite; the system of watering and hygrometrical observations in the collioeries of the Glamorgan Coal Company; Hood, 5948-6039. The Aberdare and Rhondda Valleys include the largest and driest mines of South Wales; they are fiery mines; Thomas, 6193-97. At the Standard Colliery the spray system of watering is employed; 6242-51. Additional precaui;ions are not necessary in the working of the collieries in the Aberdare and Rhondda Valleys as regards dust; 6285. Watering in South Wales; J. S. Martin, 6668-70. See also under "ABERDARE AND RHONDDA VALLEYS COLLIERY OFFICIALs ASSOCIATION." SWAITHE MAIN PIT EXPLOSION: Caused by a safety lamp passing the flame through the gauze in a current of air containing firedamp and suspended coal dust; Ashworth, 4604. The explosion carried on by dust ; 4605-607. A Stephenson's lamp; 4608. THOMAS, JOHn JAMES: Manager of the Standard Colliery in the Rhondda Valley: 6191. Gives evidence on behalf of the Colliery Officials' Association of the Aberdare and Rhondda Valleys; 6192. This association represents an annual output of eight million tons and 45 collieries; 6267-70. The Aberdare and Rhondda Valleys include the largest and driest mines in South Wales; they are also fiery; 6193, 6194. Has had 28 years' experience ; 6195-97. Believes coal dust to be a danger in carrying on explosions, and that it can carry on an explosion for a comniderable distance; 6198-6202. Is of opinion that coal dust will not explode at a naked light. Refers to coal dust at the tips where there are big fires and torches; 6203-205, 6255-66, 6291. Believes that the explosion in the hopper at Brancepeth was not due to dust but to gas given off from the dust; 6206-209, 6253-55, 6287-89. Believes that coal dust, even when so thick in the air that it would almost be impossible to breath (as he has seen it in the roads) will not explode at a naked light; 6210-14. Under such circumstances the dust might be very dangerous in the presence of a blown-out shot of gunpowder or a low explosive; 6215-17, 6237, 6290. Coal dust will increase an explosion of fire-damp; 6217, 6218, 6238. Coal dust raised by falls of roof will not ignite at a naked light; 6219, 6220. There is a distinct difference betweea fire-damp and coal dust in a safety lamp ; the one explodes, the other only flickers and sparkles. Concludes from this that coal dust will not explode at a naked light; 6221-23. If the coal dust is mixed with fire-damp, it makes very little difference inside the lamp; 6224. Believes that coal dust mixed with fire-damp is more explosive than coal dust alone; 6225. Has made experiments which show that gunpowder, or low explosives; will ignite the dust, and that the flameless explosives will not do so in any case; 6226-32. In these experiments has tested ammonite, bellite, and ardeer powder. Each showed a little flame, not, however, of sufficient duration to ignite the dust; 6233-36. Has never known a high explosive without flame, but they are much safer than gunpowder; 6278-84. As precautions against the dangers of dust, suggests the use of flameless explosives; 6239. Recommends tamping of the high explosives with a damp and non-combustible material; 6240. With regard to gas, thinks the provisions of the Mines Regulation Act quite sufficient. Believes that the dangers of coal dust might be removed by the prohibition of the use of explosives of the gunpowder class, and by modifying the condition of the dust by water as required by General Rule 12; 6241, 6285. Uses the spray system of watering, the water being under pressure. By this means perfect saturation of the air is obtained; 6242-51. Of all the high explosives, thinks ardeer powder gives the least flash; 6252. SStates that he does not believe that any of the members of the Colliery Officials' Association of the Aberdare and Rhondda Valleys are of the opinion that coal dust would ignite from an open light or even from a torch. He believes that they are all in accord that coal dust will explode by means of a blown-out shot, and in the absence of gas; 6269-75. Thinks that coal dust always gives off a little gas, but more when it is fresh; 6476. Regards it as desirable to make experiments with the various explosives; 6292-6295. TONITE: Used at Hetton Colliery: Forman, 5099. TRIMDON GRANGE EXPLOSION: Initiated by gas and carried on by dust; Forman, 5064-70. TUDHOE EXPLOSION: A dust explosion; Forman, 5068-70. USWORTH EXPLOSION: The course of the explosion described; a dust ex- plosion; Forman, 5071-3. P3 108 ROYAL COMMISSION ON EXPLOSIONS WATER, CARTRIDGE: They are used in South Wales, but witness has had no personal experience with them; Morgan, 4836, 4837, 4911-14. Has tried the water cartridge; Wilkinson, 5565. The explosion at the National Colliery was caused by an Abel's envelope used without the water; 5568, 5569; J. S. Martin, 6655. FROM COAL DUST IN MINES: WATERING-continued. In the South Wales mines most of the main roads are watered-in some cases by means of tanks, in others by means of jets; Hood, 5953, 5954. Witness prefers the jet system: thinks the system with compressed air the best, but witness gets very nearly the same result by pressure upon the water without introducing the air; 5955-64. Describes the system of watering adopted by the Glamorgan Colliery Company, and produces hygrometrical tables showing the effect upon the atmosphere under various conditions; 5965-87, 6014-17, 603739. The only really effective way of damping is by steam, but in practice it cannot be done as it brings down the top and lifts the bottom; 5984, 5985. Watering by the spray removes the danger of coal dust: in witness's opinion an explosion cannot spread along roads that are damp; 5988, 5989. Has had the dust analysed for moisture: the natural moisture in the coal is '80 per cent.: the moisture in the dust after watering is 1"84 per cent.: does not think dust with this amount of moisture would explode or ignite; 5996. Witness would only apply these watering arrangements to collieries where the natural heat is high in order to lower the temperature to make it more comfortable to work in; 6011. The quality of the dust has something to do with it: does not think such watering arrangements are necessary in the Scottish mines; 6012, 6013. Uses the spray system with a pressure on the water, without compressed air, and obtains perfect saturation; Thomas, 6243-51. A highly desirable and necessary precaution, but not totally effective; J. S. Martin, 6605, 6606. This statement applies to the spray system in use in South Wales; 6643-50. The extent to which watering is practised in the South-western district; 6660, 6668-70. WATERING AS A PRECAUTION: Watering no value whatever; impossible to prevent an explosion by watering the place before shot firing as the dust does not become saturated; thoroughly wet places in various parts of the mine will arrest an explosion: Ashworth, 4643. 4718. A damp space of 70 yards quite long enough for this purpose; probably a good deal less will do; 4644. Morfa Explosion referred to as an illustration; 4713. Believes watering is not of any value ; 4715. Where watering has been done, it is as dry as tinder underneath; 4716. Recommends watering as a sanitary measure; it makes the roads pleasanter to travel on; 4717-4719. Suggests that watering may become a source of danger; should an explosion occur, it is possible that the aqueous vapour may serve to increase the effcots of it; 4717. Watering, as practised in South Wales, is effective, and keeps the dust damp; Morgan, 4822-25. Water provided in sprays and carried in by the intake air is excellent, and improves the health of men and horses; 4839, 4840. Where done effectually, the use of gunpowder could be continued with little or no risk in South Wales mines; 4841. Watering does not dispense with the necessity for removing the dust to a thin covering; 4842-44, 4897. Attaches more importance to the watering of the dust than to its removal; 4898-900. In South Wales the dust is removed and thoroughly watered ; 4901-904. Watering is a practicable precaution as far as the travelling roads are concerned: impracticable to WEDGE, THE: Not used extensively in Durham: it answers well but water the dust in the working faces; Isaac, 4942, is very hard work and the men prefer roburite as 4943, 4947. The intake is not sufficiently saturated with moisture to lay the dust in the faces; 4976-79. being easier; Forman, 5122-29. Recommended as a substitute for explosives; Woods, Watering should be done, especially in the intakes or 5203-12. any places where there is an accumulation of dust: npt possible to water the working faces; Forman, Explains that he means any patent wedge; 5315-20. Grafton Jones' Hydraulic Wedge, Chubb s Wedging 5079-82. A damp district untouched by the exMachine, Bidder's Wedge, tried in South Wales; plosion at Trimdon Grange and at Usworth; 5066, Wilkinson; 5565. The wedge not generally appli5067, 5071. A few yards of dampness sufficient to cable: cumbersome, expensive, and liable to get arrest an explosion; 5116-18. out of order; 5566. Is using the long feather A safeguard against explosions where it can be done, wedges and finds it answer very well: only uses it and makes the mine pleasanter to work in; Woods, in the stone: in an ordinary shale roof, a few 5296-99. minutes are sufficient to break the stone down: if Considers that the damping of the dust is the chief hard, it may take two hours : much safer than any means of preventing the extension of explosions; flameless explosive, but not much used on account H. W. Martin, 5354. Explains the spray system of of the expense and slowfless of the process ; 5630watering which has been employed at three of the 43. Dowlais Iron Company's Collieries since 1886: compressed air about 45 lbs. per square inch : damps the WEST STANLEY EXPLOSION: dust in the intakes anud returns: the sprays are placed A dust explosion; Forman, 5071. from 50 to 80 yards apart: probably one in every 200 yards would sufficiently damp the dust: in order to carry the saturation a considerable distance WILKINSON, GEORGE WV1LLAM: it is desirable that the water, even when it is at General manager of the Risca Colliery and the Aberhigh pressure itself, should be accompanied by air carn Colliery in Monmouthshire, and the National at high pressure also: by this system the dust is Colliery and North Dunraven Colliery in the absolutely damped : the spray incidentally improves Rhondda Valley, Glamorganshire; 5535. the ventilation and temperature of the mine: at the These mines are very dry, and dusty, and gaseous; South Tunnel pit about 3,000 yards of piping laid 5536. down: with this system believes an explosion of Gives the details of an explosion at Risca on coal dust to be impossible: inexpensive to apply January 15, 1882, by which four men and 60 horses especially where compressed air is already workwere killed. Considers that dust was raised in the ing; H. W. Martin,5375-5410. Witness knows of no air by two shots, and fired by a third which had objection to the use of the spray: all that is neceshung fire and blew out. A fiery mine, but the sary for the purpose of damping the dust could be accident occurred in the main intake two or three carried out without doing damage to floor or roof; hundred yards from the bottom of the pit where it 5414-16, 5448-70. Watering makes the mines was impossible for gas to have been present. pleasanter to work in, 5425. Only carries the Impossible for gas to have been drawn out of the damping to the working faces in one instance: old workings by the firing of the shots; 5537-48, generally confines it to the most dusty parts of the 5571-78, 5595-603. main roads, 5505-11. Believes coal dust to be a very serious danger, and Approves of the spray system; Wilkinson, 5552, 5553. that it may cause an explosion even in the absence Regards watering as so imnortant, ranl so necessary of gas; 5549, 5550. to the safety of the miiie that he considers it should To guard against the danger he thinks it necessary be automatically maintained; 5554-56, 5609-11. to thoroughly water the ways; in fact, to saturate Would prefer to use compressed air if possible; the atmosphere,; 5551, 5607. 5557, 5558. Approves of the system of watering with a spray 'Has an objection to watering as it softens the strata under a pressure of compressed air; 5552, 5553. in the roads: prefers to remove the dust instead; Thinks the saturation of the atmosphere is so absoBedlington, 5699-5704. lutely necessary to the safety of the mine, that he TNDEX. WILKINSON, GEORGE WILLIAM-continued. recommends that it might be automatically maintained; 5554-5556, 5609-11. Prefers the compressed air system of damping ; 5557, t9558. Advises the use of explosives as nearly flameless as possible; 5559, 5560. Has been using ammonite for the last two or three years, and has never had any complaints from any of the shot-firers of their having seen any sparks or flames, and has had no complaints of the fumes ; 5561, 5562, 5585, 5604, 5612-22. Does not think powder is necessary in any mine. Ammonite does its work well; 5563, 5564. Has. tried the Grafton Jones' hydraulic wedge; Chubb's wedging machine; the compressed cartridge used in Staffordshire, the lime cartridge, and Sir Frederick Abel's water cartridge; 5565. The wedges are not applicable for several reasons; 5566. Safer than the most flameless explosive, but expensive and slow; 5629-43. If a flameless explosive, like ammonite, were used in shot firing, and the air of the mine kept saturated, thinks there would be practically no danger from coal dust; 5567, 5625-28. Refers to an explosion at the National Colliery in which dust, he considers, played a part, and which was caused by the careless use of an Abel envelope ; 5568-70, 5583, 5584. The explosions both at Risca and the National Colliery did not pass damp places; 5579-82. Has had several blown-out shots with ammonite; 5586-89. Uses no explosives in the actual coal getting; 5590, 5634-36. Impossible to carry on the collieries of South Wales without explosives; 5591. To abolish explosives in the mines under his superintendence would increase the cost of working by about a shilling a ton; 5623, 5624. Does not think that the duty of reporting accumulations of coal dust could be put in the hands of any fireman or any individual; 5592-94. Believes further experiments are very necessary; 5644-53. They should be made in a long gallery on the surface, and it should be the width of an ordinary heading in a mine; 5644-53. Small experiments would not be convincing; 56541-57. WOODS, SAMUEL : President of the Lancashire Miners' Federation, which has a membership of 42,000; 5176, 5177. Vice-President of the Miners' Federation of Great Britain, with a membership of about 178,000; 5178, 5179. Worked for about 22 years in the Lancashire mines ; 5180-83. Believes that " coal dust may act as an auxiliary or an intensifier upon an originated explosion"; 5184. Coal dust cannot initiate an explosion; 5185, 5292. Has been in the most dusty mines imaginable, where gunpowder was used a4d libitum, and yet never saw the slightest traoe of danger of an explosion arising from dust; 5186. No analogy between the experiments of Mr. Hall, and others, and the conditions of a coal mine; 5187, 5188. In Lancashire the fiercest explosions have been in the mines which were the best ventilated; 5190. In these cases, he attributes the explosions entirely to gas, and believes that the gas in the Lancashire 9-feet seams is entirely different from that in most mines-that it travels with the ventilation and is not so easily perceived; 5191, 5192, 5252-62. When an explosion is caused, coal dust may extend it for a short distance; 5193, 5293-95. Describes an accident in Laffak Garswood mine. The place was completely enveloped with dust, but yet there was not the slightest trace of the dust being ignited by the flame which was produced; 5194, 5263-84. 109 WOODS, SAMuEL-continued. Has never seen the slightest trace of caked or )burned (Iust after an explosion, and is rather suspicious about statements of its existence; 5195-5200, 524751. Believes that all explosions are due to gas, and that dust only plays any part in very exceptional circumstances; 5201, 5202. Believes that shot-firing--w heher by gunpowder, roburite, tonite, dynamite, or any of the patent explo sives-ought to be abolished; 5203. Does not know of anything else that could be employed in the place of shot-firing, except the wedge; 5204, 5205, 5315, 5316. The wedge could be used universally in coal mines. Thinks coal, as hard as any seams in the country, is being got in Lancashire without any kind of explosives; 5206. To abolish shot-firing would, of course, increase the cost of mining, but the increase, he thinks, would be very little; 5207-211. At a miner's conference in 1887, believes that the whole of the representatives, with the exception of those from South Wales, were agreed to advise the Government to abolish shot-firing altogether; 5212-14. Speaks from experience in his own district, and only speaks with reference to South Wales from imported knowledge; 5215. Qualifies his suggestion on the prohibition of shotfiring. In rock, or for driving through hard measures between seam and seam, &c., there might be exceptional treatment. Thinks that some of the patent explosives, if under proper supervision, and at proper time, might be used with perfect safety: 5216-20, 5240. There might be greater freedom with regard to powder in open light collieries, but is convinced that no mine is safe from an irruption of gas ; 5225-30. Would limit the prohibition of gunpowder to collieries where there was a liability to irruption of gas: 5225-30. In the Lancashire mines the coal can be got without explosives. They simply have the coal to deal Q with, and do not interfere with the rock floor and roof; 5231-38. Has noLhing to suggest with regard to what is the common practice in all coal fields now with respect to setting off shots when there are not many men in the pit; 5241. So long as there is shot-firing in dangerous seams there is always a liability to explosions, and suggests that, if shot-firing is allowed, the Mines Act should be literally carried out; that there should be an adequate amount of ventilation, and that the managers should see that the safety clauses are carried out with a view of preventing accidents; 5243. Believes there are exceptional cases where the Mines Act is not carried out; 5244, 5300. Thinks the Act is fairly carried out, but is of opinion that there is not sufficient inspection; 5245, 5246. Watering is a safeguard a,gainst explosions and makes the mine pleasanter to work in; 5296-99. If the First General Rule with regard to ventilation is rigidly carried out, and sufficient precautions are taken with regard to the shot-firing clauses and watering, he does not see what other remedy could be suggested; 5302-305. Falls of roof and naked lights; 5306-308. To prohibit shot-firing would come very heavy on the collieries working hard seams; 5309, 5310. Believes Seaham explosion was due to gas: 5311-14. Refers to the case of a Lancashire collier who is said to have been poisoned by the fumes from roburite; 5320-324. The high explosives are safer than gunpowder but not so effective; 5325. Believes that 90 per cent. of the workmeir belonging to the association of which he is vice-president hold the opinion that dust cannot originate an explosion; 5326-28 This book is a preservation facsimile produced for the University of Illinois, Urbana-Champaign. It is made in compliance with copyright law and produced on acid-free archival 60# book weight paper which meets the requirements of ANSI/NISO Z39.48-1992 (permanence of paper). Preservation facsimile printing and binding by Northern Micrographics Brookhaven Bindery La Crosse, Wisconsin 2013