ILIBRARY OF CONGRESS J I <^/«^. Q.C...^i c Z19 UNITED STATES OP AMERICA. Digitized by the Internet Archive in 2011 with funding from The Library of Congress http://www.archive.org/details/bottomofseaOOsonr T H F. BOTTOM OF THE SEA Ruins of the Temple of Hercules at Gibraltar. T H K BOTTOM OF THE SEA. B Y L. S C) N R E L. TRANSLATED AND EDITED BY ELIHU RICH, fRANSLATOK OF CAZIN's POPULAR TREATISE ON "THE PHENOMENA ANL UAWS OK heat;" LATE EDITOR OF "THE PEOPLE'S MAGAZINE," ETC., ETC. NEW YORK: SORIBNER, Armstrong' & co., SUCCESSORS TO CHARLES SCRIBNER & CO., C54 BROADWAY. 1872. Illustrated Jibrary of Wonders. PUBLISHED BY JtHrasrs. (fferto ^tr'Amx Sc <^o., C54 BROADWAY, NEW YORK. Each one volume 12mo. Price per volume, $1.60 Titles of Books. Thunder and LianxNiNa, . Wonders of Oi'tics, Wonders of IIeat, Intelligence of Animals, Great Hunts, . Egypt 3,300 Years Ago, . Wonders op Pompeii, The Sun, by A. Guilxemin, Sublime in Nature, . Wonders of Glass-Making, Wonders OP Italian Art, . Wonders op the Human Bodt, Wonders op Architecture, Lighthouses and Lightships, Bottom op the Ocean, , Wonders op Bodily Strength and Wonderful Balloon Ascents, Acoustics, Wonders of the Heavens, The Moon, by A. Guillemin Wonders of Sculpture, Wonders op Engraving, Wonders op Vegetation, Wonders op the Invisible "World, Celebrated Escapes, Water, Hydraulics, Electricity, Subterranean World, \V0NDKB8 OF EuROPKAlf AkT, Bkill, No. of Illustrations. 39 70 &4 22 40 22 58 50 63 28 45 5U 60 68 TO 30 114 48 60 61 32 45 9T 26 T7 40 71 2T 11 * In Press for early Publication. The above works sent to any address, post paid, upon receipt of the price by tl piibliaheru. TEANSLATOR'S PREFACE. This little book supplies a general and instructive outline of a certain number of interesting facts con- nected with the sea. It bears the same relation to the strictly scientific treatment of the subject as a popular lecture on art to instruction in the studio, a ramble through a museum to a lecture on science ; or a short pleasure-sail on the coast, with here and there an opening glimpse of the scenery, and a pleasant chat on the wonders of the deep, to an ac- curate survey and a formal report on the same sub- jects. Occasionally, it may be hoped, the reader will find something more in the following chapters on " The Bottom of the Sea," than these remarks would lead him to suspect ; but its pretensions are not such as would justify the kind of criticism which a scien- tific treatise like that of Professor Tyndall's book on Heat, and many works of less scientific importance, are rightly supposed to challenge. Our knowledge of the sea is not, indeed, so exact as to justify the same high pretensions to accuracy, vi T U AN S LAWKS F RE FACE. even in a strictly scientific elucidation, of which many otlier investigations admit; and yet, as Franklin observed in his time, what persevering efforts have been made to master the secrets of the abyss, and what dangers have been encountered in the struggle of man with its gigantic forces! Michelet commences his well-known book on the subject by remarking that the first iraj>ression which man receives from the Ocean is one of dread ; but if tliis observation be just, that dread of the vast an 1 unknown lias in all ages been converted into a source of inspiration, until men of genius have rchieved their greatest triumphs where they feared the most. Some of these achievements are remarked upon in the following pages. But the complete record of similar conquc sts would fill a volume, for it is always on the shores of the sea, and by means of the sea, that men have established their communi- ties, and spread their civilisation over the earth. The sea, not dreaded but loved, and used as a mighty agency, is truly the " Vita Nuova of Nations." While touching slightly on this topic, and avoiding the dryness of scientific details, this book will be found to give a general idea of the configuration of the sea-bottom, (5f the action of the sea upon its shores, and of some of the more impressive wonders of the deep. The reader, hitherto uninitiated intc nUXiSLATORS F HE FACE. ix tliis branch of study, will iind, in coiu'lusioii, tluit he has learned somewhat of th(; gieat law of porpotiial motion and change in what he may have previously deemed the immoveable crust of the earth. He will have learned to regard the mystery of that movement with a measure of the same awe that is inspired by a study of the distant nebulaB ; and he will have felt how es>enticil it is, in studies of this nature, to disembar- rass his mind of ideas borrowed from limited views of the measurements of time and space : God woiketh slowly; ami u tliousaud ycnrs He hikes t) lift His hand off .... MuswELL Hill, January, !87 iii:iii!ii"!ii':iiiiiiiiiiiiiiiiiiiiif:[r CONTENTS. SUBMAh'INE OROGRAPHY. r.\i:!4 1. The plummet — Brooke's deep-sea sounding app,;riitu.s . 1 2. Construction of chaits and sections of the ocean-bottom — But little as yet known of this subject — Maury, the founder of submarine orographic science ... 8 S. Analogy between the configuration of continents, and that of the bottom of the sea — Equatorial section of the eaith 18 4. Northern Atlantic Ocean — Chart of Maury . . .27 5. The Mediterranean and the Black Seas — Chart of Bottger '61 6. The Baltic— The North Sea— The Straits of Dover— The English Channel — The Bay of Biscay . . . 1-57 VRE WATKR OF THE OCEAN. 1. Composition of sea-water — Biot's apparatus . . .42 2. Variations in the saltness of sea-water . . . .47 3. Variations observed in the gases contained in sea-water . 52 t. Solid bodies in the sea — Phosphorescence . . .55 5. Colour of sea-water — To what extent influenced by matters held in suspension, by the bottom of the sea, and by the agitation of ihe water . . . . . .(',.; G. IMeasure of temperature i.t the bottom of the sea . . (j8 7. Diminished temperature of the sea in proportion to the depth — Irregularities introduced in this law by the in- fluence of submarine currents — Temperature at the bottom of the ocean constant and uniform — Princi]ial causes of submarine currents , , . . .70 xii CONTENTS. PAGB 8. Cause of waves — Their height — Thickness of the mass of water in motion — Ground-swells — " Raz de MareV — "Waves of translation — Measure of a wave of translation, and of its speed, in the Pacific Ocean — Tides — Resume 74 DEPOSITS IN COURSE OF FORMATION AT THE BOTTOMS OF SEAS. 1. Universality of the process of sedimentation — General view of the mechanism of this phenomenon . . . .80 2. Action of waves upon the coasts — Destruction of rock- bound shores by the sea — Pierced rocks — Silting-up of shallow waters by marine alluvium . . . . ^9 3. Deposits in mid-ocean, and deposits on the coasts — Im- portance to geologists of coast-deposits as data for fixing the limits of ancient seas — Deposits of the French seas ......... 94 4. Transport and deposit of rocks by floating ice . . . 99 5. "Water-springs in the earth — ^Funnels or wells of the Jura — The Aveii of the South of France — Katavotron — Sink- holes — Geysers — Submarine springs — Origin of oolitic formations ....:. .102 SUBMARINE LIFE. 1. Exuberance of life in the depths of the ocean — Tableau' of the tropical seas — Life in the seas of the temperate and the frozen zones — Natural illumination of the oceanic abysses 1 09 2. Migration of marine animals — Nests at the bottom of the sea — Fisheries 124 3. Terrible conflicts of marine monsters — Massacre of the weak by the strong ... .... 142 4. Animated forests — Animal stones ..... 161 5. Sponges . . . . . . . . . 165 '6. Polypi — Their genernl structure — ^Reproduction of polypi — Vegetative life of polypi — The polypier — Two great classes of polypi distinguished by the form of the polypier — The Tubipora mu.sica 170 CONTI'JNTS. xiii TAOF. 7. Hydra, type of the hydrozoa or hydra polyps— Extraor- dinary properties of the hydra discovered by Trembley — Marine hydrozoa . . . . . . .17(5 8. ActiniaB — Sea-anemones — Sea-nettles . . . .184 9. Coral — Miraculous virtue attributed to coral by ancient tradition— Coral stone — Coral plant — Marsigli discovers the fl(jwers of the coral — Observations of M. Lacaze- Duthiers 186 10. Coral chiefly found in the Mediterranean Sea — Various species of coral — The coral fishery — Antipathes, com- monly called black coral ...... 189 11. Gorgons of the old writers-T-Tiieir animal nature discovered by Peyssonnel, Trembley, and Bernard de Jussieu — The fan-gorgon — Its cosmopolitan character . . . 191 12. The more active submarine constructors — Astroides — Caryo- phillia — Madrepora plantaginea — Dendrophyllia — Occu- lina, or white coral — Meandrina — Fungia — Porites — Milleporae 195 13. Galley-slaves of the sea — The giants and pigmies of crea- tion — The suckers — Legends of monsters — Singing fishes 207 14 . Algse — The untrodden forests and prairies of the ocean — Animal life more abundant than vegetable life — Sea- plants less widely distributed than marine animals — Influence of light — Collection of seaweed on the coasts — Assistance aflbrded by the tide .... 224 MAN AND HIS WORK AT THE BOTTOM OF THE SEA. 1. The empire of the seas denied to man — Numerous attempts at submarine exploration — Disturbance of present social conditions which would ensue from the possibility of travelling beneath the surface of the water — The sea the best tie between nations ...... 231 2. Exploration of the bottom of the sea — Diving apparatus — Invention of MM. Kouquayrol and Denayrouze — Sub- marine electric illumination — Salvage of objects sunk in the sea — A chest of gold recovered under peculiar cir- cumstances in the port of Marseilles .... 243 3. Gowan's salvage of Russian vessels in Sebastopol Harbour 255 XIV CONTENTS. PACK 4. Ships repairt.d without leaving the water, and even while under sail . . . . . . . .259 5. Sensations of the diver — Depth to which it is possible to descend . . . . . . . . .261 6. Extreme difficulty of working below water — Submaiine foundations— Ston*^ worked when in position . . 2Gt) 7. Diving-beJls — Stationary cjmprcssed-air apparatus . . 270 8. Payernes submarine hydioatat ..... 274 U. Villeroy's submarine bi at . , . , . . 278 10. Employment of torper'oes in clearing channels and the entrances to ports ....... 280 U. English mines beneath the ocean ..... 284 CHANGES IN PROGRESS AT THE BOTTOMS OK SEAS.— THEIR UNIVERSALITI^ Extent of the movements of the terrestrial crust — Nature incessantly at work — The gradual cooling of the earth a cause of its present form, owing to the crumpling and breaking of its crust ....... 286 Tlie shore — Its apparent fixity — Traces of the presence of the ocean almost univer&al ..... 29o Progressive enlargement of the Str;dts of Gibraltar during the historic period — Columns of the ancient TemjDle of Hercules submerged — Descriptions left by Avienus, Pliny, and Pomponius — Mellarla, Carteia, and Belon submerged — Otiier examples of cities and islands covered by the waters, and of mountains violently separated from continents ....... 298 The quantity of water which covei's the earth is sensibly •,onstant — An elevation in one point is balanced by a corresponding subsidence in another— Aristotle's opinion about the (Ireek traditions of the Deluge — The earth will become drver and colder . ..... 304 SIT[)[)EN ]\IOVEMENTS OK THE bUBMARINE SOIL. I. Earthquakes modify the bed of the ocean — Submarine volcanoes ........ 308 (x>yrM\Ts. XV TAOB 2, Greek Arcliipclngi) — Dclos and Rlio;les upheaved from th(! bottom of the sea — Siu-ct s^ive additions to the Archi- pelago of Santorin ....... 310 3 'J'lic Azores — Appearance and disnppearance of islan Is sub- sequent to earthquakes — The eplieineral island Sabrina . 815 4. Submarine volcano in the middle of ti.e Atlantic . . 318 5. Subm irine eruptions near Kamtscli itka— Iceland — Ig litcd sea; appearance of an island near Keikiane.ss — Kisn of a fiery island from the ocean, near the Aleutian Isl I s . 319 (). The bottom of the sea feels the counterblow of terrestrial volcanic jihenomena ....... 322 7 Products of submarine volcanoes — How they differ from the pro lucts of subaerial volcanoes .... 324 8. Bottom of the sea brought to light in consequence of the eruption of submarine volcanoes . . . 328 GRADUAL CHANGES OK THE BOTTOM OF THE KEA. 1. How the gradual change of the sea-bottom can be demon- strated — Modifications which the map of Europe would sutler by a gradual subsidence of thirty feet in a century — Paris submerged — Europe as it would be were the level of the sea raised 500 feet — Toulouse and Vienna as sea- ports ......... 331 2. Ancient limits of the Black Sea — Drying-up of the Russian steppes ......... 338 3. Movements of the earth in the northern hemisphere — Sub- sidence in the north of Euiope and of America — Elevation of the polar regions — Sinking of the coast of Sweden . 340 4. Elevation of Spitzbergen — Sinking of the western coast, and elevation of the eastern coast of Greenland — Gradual submersion of the forests of Labrador and of Nova Scotia — Eoman constiuctions engulfed in the Low Ccnintries — Origin of the Zuyder Zee — Failure of the Dutch sea- dams — The valley of the Somme and the coasts of Nor- mandy follow the movenK nt of subsidence of the Low Countries , ...... 344 5. Two extensive zones of subsidence iu the southern hemi- sphere — They are separated by a zone of elevation — The F ji Islands have been sinking diiri g 300.000 years . 347 xvi CONTENTS. ACTION OF RIVERS AND CURRENTS ON THE BOTTOM OF THE SEA. PAGE 1. Choking of ports with sand — Deltas, and the action of the tide upon them — The formation of deltas may be either favoured or retarded by marine currents according to ciicumstances — Deltas formed in shallow seas — Eapid growth of the delta of the Po due to the clearing of the south side of the Alps, and to tlie damming-in of tiie shores of the river ....... 851 2. Egypt, according to Herodotus, a present from the Nile . 357 3. DL^scription of the delta of the Mississippi — A village at anchor — Ships lost in the sand and mud of the river . 360 4. Eiipid f^rowth of the deltas of the Po and of the Mississippi — Delta of the Nile enlarged by seven miles during the historic period — The Ehone ..... 36? 5. Littoral accumulations — Coast-line — Marine lagoons and pools —Lagoons moved inland by the effects of the dunes in Gascony— Villages buried beneath the dunes near St. Pol-de-Le'on in Brittany, and also in Gascony— Bordeaux menaced 371 6. Floating icebergs — Polar winters 37<- INFLUENCE OF LIFE ON VARIATIONS IN THE BED OF THE OCEAN. 1. Formation of coral reefs ; limit to their growth — Condi- tions favourable to their development .... 380 2. Life and inanimate nature — Coral insects die in the calm of dtep waters — Explanation of the formation of the deep reefs of the Pacific Ocean — Coast reefs — Broken reefs — Barrier reefs of Australia — How the coral reef becomes an island 383 3. Slowness of the growth of coral reefs — Florida Keys — De- struction of coral islands during a tempest in January 1865— Kegions in which coral reefs are found . . 390 4. Algaj — Submarine forests and prairies — Floating seaweed of the Sargossa seas — Extension of the coasts by the Rhi- zophora Mangle . . . . . . . 393 INSIGNIFICANCE OF MAN COMPARED WITH THE OCEAN 396 LIST OF ILLUSTEAriONS. I'AOK Ruins of the Temple of Hercules at Gibraltar Fronihfiece 1. Man's conquests of Nature ...... vii 2. Brooke's deep-sea sounding apjjaratus .... 4 3. Striking the sea-bottom 5 4. Measuring the depth of the sea by means of a bomb . . 7 5. Vertical section of the Atlantic from Yucatan (coast of Mexico) to Senegal ....... 10 6. Section of the Atlantic Ocean from Paris to Newfoundland 23 7. Equatorial section of the earth 25 8. Chart of the depths of the Atlantic Ocean . . .29 9. Chart of the respective depths of the Mediterranean, the Adriatic, and the Black Seas , . . . .33 10. De{)th3 of the Adriatic ....... 36 11. Profile of the ocean-floor from the southernmost point of Norway, via the Straits of Dover, to the 10th degree of west longitude and the 47th degree of north latitude . 39 12. Vertical section of the Straits of Dover ... 40 13. Phosphorescent sea at Simon's Town, Cape of Good Hope 57 14. Incidence of tl:e rays of light on a calm sea . . .66 15. Incidence of the rays of light on the waves of tlie sea . 67 16. Rising of the sea at Acapulco . . . . .79 J 7. Waves breaking against a rock-bound coast . . 90 18. Rocks worn througli by the waves . . . . .93 19. Section of the sea and the sea-bottom in the track of ice- bergs between Greenland and Newfoundland . . 100 h LIST OF ILLUSTRAriONS. 20. Cause of subuiaiine springs 21. Dabs and soles 22. Poulpe, or cuttle-fish 23. The hippocampus . 2i. Herrings attacked by tunny-fish 25. Fight between a swordfish and a whale 26. Fight between a sailor and a shark 27. Turbots 28. Fishing for sponges on the coast of Syria 29. Coral with polypi more or less expanded . 30. Branch of coral with polypi indrawn 31. Organ-pipe coral .... 32. Sea-pen (Penuatula spinosa) . 33. Veretillum cynomoriura 34. Spicule of coral . ... 35. Portion of the fan-gorgon, magnified 36. Dendrophyllia ramea .... 37. Caryophillia cyathus .... 38. Astrea punctifera . . 39. Madrepora plantaginea .... 40. Dendrophyllia (half the natural size) 41. Meandrina cerebriformis 42. Millepora alcicornis (one-fourth of the natural size) 43. Fungia agariciformis 44. Gneit^s bored by the Pholades dactylus 45. Malayan divers fishing for holothuria 46. Divers dressed in the apparatus invented by MM quayrol and Denayrouze . 47. Divers finding a box of gold in the port of Marseilles 48. Salvage of Eussian ships sunk at Seba=topol 49. Caulking a ship while uuder sail . 50. Sinking blocks of artificial stone at Cherbourg 51. Vertical section of breakwater at Cherbourg 52. Diving-bell PAG 5 . 10? . Ill . 115 . 121 . 129 . 145 . 149 . 152 .167 . 172 . 173 . 175 . 183 . 183 . 185 . 192 . 196 . 197 . 198 . 199 . 200 . 203 . 204 . 206 . 209 . 237 Rou- . 271 LIST OF ILLUSTRATIONS. 53. Fixed apparatus, supi (lied with compr. sscd aii 54. Paycrnc's submaririo livdrostat 55. Villeroy's subiuaiiue boat 5(). Removing an obstruction by means of a torpctl 57. Section of a tin mine in Cornwall . 58. Vertical section of tlie Straits of Gibraltar 59. Irruption of the sea in Zealand 60. Eruption of a submarine volcano . 61. Submarine eruption at the Azores . 62. Rise of a n(nv island near Ouniraack 63. Eruption of 'J'omboro in 1821 64. Paris covered by the sea 65. A village buried under sand dunes 66. Floating glaciers 67. Telegraphic cable at the bottom of the oceaii PAQR . 27a . 276 . 279 282 . 285 . 300 .. 303 . 309 -. 316 . 320 . 323 . 335 . 374 . 377 , 399 THE BOTTOM OF THE SEA. SUBMARINE OROGRAPHY. 1. The riuinmet— Brooke's Deep-sea Sounding Apparatus. In these days of great achievement, when a voyage round the world has become a holiday trip, the youngest boy who is capable of construing Horace may wonder that a time ever existed when it was thought to be an act of impious daring to cross the Ocean. Nevertheless, it may be worth a moment's reflection to realise the actual position of a ship which has spread sail for some distant port, and left familiar coasts far behind. What shall wi* call a vessel under these circumstances? A house floating in mid-ocean, on a shoreless sea, with nothini'" visible around but the heavens, overarching every- where the monotonous waste of waters. The ship ii'iils on, with the dritting clouds above, and t)i»j B 2 THE BOTTOM OF THE SEA. currents of ocean below. By what miracle shall the sailor be able to keep on the track to his des- tined port ? By what means shall he ascertain the position he occupies on the vast extent of ocean? The science of astronomy comes to his help, fur- nishing him with the most simple and exact pro- cesses, by which he may discover at any moment the route he is following, and the distance which yet separates him from his haven. It is by her did that he is able to pass safely through dangers almost numberless, to avoid iron-bound shores and reefs, against which he would blindly hurl himself to destruction if the stars did not light his uncertain way. But it sometimes happens that the observance of the heavenly bodies fails the mariner at the very moment when he is most in need of their services. Let us recall, for example, the numerous dangers, even when the sea is quite calm, in which the ship is involved which involuntarily approaches a coast hidden from view by a thick curtain of fog. In this and analogous cases, the seaman resorts to other means for help than those furnished by astronomy. Among the means most universally employed is the plummet. It may be that the good ship is slowly drifting on to a bank of sand or gravel which would be its destruction. The lead is thrown, and the sea THE. PLUMMET. 3 sounded. In the approaches to some coasts or harbours where dangerous rocks abound, the plum- met is indispensable as a means of discovering the depth and character of the bottom. Is it mud, or sand, or gravel, or rock? Will it be advisable to cast anchor, or to find a more favourable situation ? The plummet will answer these questions. In its simplest form this little instrument con- sists of a cylinder of lead, suspended by a cord attached to one of its extremities, while the other is tallowed in order that some portion of the soil at the bottom of the sea may adhere to it. It is simply dropped into the water, and allowed to fall suddenly to the bottom. The imperfection and un- certainty of such an instrument are obvious. If the sea be calm and of slight depth, it may prove equal to its work, and report correctly. But how often is the lead pulled up without anything adhering to it ! The sea, in fact, is seldom or never at rest, and at all times there are currents below the surface, which may carry away in a bight hundreds of yards of the line, without indicating that the lead has reached the bottom. Various attempts have been made to improve the plummet. The object has been to make quite sure that it shall bring up to the surface a sample of the soil at the bottom of the sea, and to diminish the THE BOTTOM OF THE SEA. effect of curreuts, so that no error may be occasioned by the length of line carried away out of the per- pendicular. The most ingenious of these improved Fig. 2. — Brooke's Deep-sea Sounding Apparatus. contrWances is that invented by Passed Midshipman Jo M. Brooke, of the United States Navy, who was at the time associated with the celebrated Maury. DEKF-SEA SOUNDING. This clever contrivance, since well known as Brooke's *•' Deep-sea Sounding Apparatus," is represented in the annexed engravings (figs. 2 & 3). aa is a cannon- Fig. 3. — Stiikicg the Sea-bottom. ball, perforated, so that the rod or cylinder, bb, maybe passed through it. Fig. 2 shows the apparatus ready for beinir lowered into the sea. The caunon-ball is 6 THE BOTTOM OF THE SEA. supported a certain distance up the rod, on wliich i* slides freely, by means of the sling dd, the ends of which are looped on to the moveable ears at the top of the rod. To these also the line is attached by which the apparatus is lowered into the ocean. Th« weight of the shot, being sufficient to resist a curreni carries the line down perpendicularly ; and when th< protruding end of the rod strikes the bottom (fig. 3) the line slackens, the moveable ends drop, and th< loops of the sling are disengaged. The shot thej slides down the rod, and the latter, no longer en cumbered with the weight A, can be drawn up wit) ease. It will be seen that a sort of cup is formed a the lower end of the rod, and this is " armed " witl soap or tallow, so that a specimen of the submarin soil may adhere to it : or the barrel of a commoi quill is attached to the rod, which is said to answe better. By either contrivance specimens of the sea bottom have been brought up from a depth of nearh four miles. Every time this apparatus is used th( shot and sling are of course lost, the rod alone being recovered when the line is pulled in. Attempts to sound the sea before the invention of this method have produced results which are now regarded as being of little or no value. The honour of having made the first attempt belongs to Peter the Great, who constructed an apparatus DEEP-SEA SOUNDIXG. with liooks, especially for the Caspian. Others, guided by theory, liave devised petards which were to be exploded, or bells which were to be rung, a certain number of i'eet below the surface of the ocean; and it was hoped that an echo would be heaid %A€ Fig. 4. — Measuring the Depth of the Sea by means of a Bomb. from the bottom, the distance of which could of course be calculated. Experiments of this kind were made when the winds were hushed and all was still ; but echo was silent. M. de Tessan suggested the more likely method of letting a bomb fall into the 8 THJi: BOTTOM OF THE SEA. sea wliich would explode when it struck the bottom. The noise of the report would reach the surface, and the time that had elapsed from the moment the bomb was dropped into the water would aiford the means of calculating the vertical distance it had fallen. It is well known that water is a good trans- mitter of sound. Dr. Colladon caused a clock to strike under the water of the Lake of Geneva, and it was heard in the first experiment four leagues off, and in the second at more than twdce that distance. However, no apparatus has been contrived which solves the problem so thoroughly as the invention of Brooke. 2. Construction of Charts and Sections of the Ocean Bottom — But little as yet known of this subject — Maury, the Founder of Submarine Orographic Science. Let us imagine the commander of a vessel sailing across the ocean to be capable of taking sounrlings in- cessantly from the first to th e last moment of his voyage, his apparatus being so contrived that the line would shorten or lengthen with such exactness, according to the varying depth, that the lead always just touched the bottom. His observations, in such a case, woul I bear a close resemblance to those which would be made by a boatman crossing a river in the sann* way. The plunnnet would at first sink to a certain CONSTRUCTION OF CM A UTS. i* depth, then it would rise, then sink lower again ; ami so go on rising and falh'ng at various intervals, unt 1 the ship arrived at some island or continent, when the lead would, of course, be once more level with tlie surface. If we imagine, further, that the com- mander was careful to record his observations from moment to moment, and, finally, to trace on a sheet of paper the section formed by the constantly varying length of the plummet line, we should see at a glance the exact configuration of the sea-bottom throughout the ship's course irom one coast to the other. Fig. 5 is a vertical section of the Atlantic, in a line from Mexico, across Yucatan, Culm, San Do- mingo, and the Cape de Yerds, to Senegambia, on the African coast ; and it may be regarded as the result of such a voyage as we have imagined. The horizontal line represents the level of the sea. The irregular line which cuts it in many points follows the undulations of the sea-bottom. Where it rises above the horizontal line there is land — that is to say, the solid crust of the earth is higher than the waters. Where its curve falls below the horizontal line, the land is submarine, or under the water. Thus, supposing that we take our departure from the Mexican coast, the plummet descends at first nearly 2000 leet, and returns to the surface on the coast of Yucatan. After doubling this peninsula, 10 TEE BOTTOM OF THE SEA. there is again an abrupt descent of about 3300 feet ; and from tiience to Cuba the valley is only inter- rupted by a chain of submarine hills of little im- portance. Eoundiug Cuba, we find ourselves floating above a perpendicular ravine, from 7000 to 8000 feet deep, between that island and Hayti. Between 90° 80° * 70° 60° 50^ 40° 30^ 20° 10^ Senegal [ The scale on the left hind of the diagram is in metres depths are given in equivalents of feet. ~\ Fig 5. — Vertical Section of tlie Atlantic from Yucatan (coast of Mexico) to Senegal. Hayti and Porto Eico, and between the latter and the Windward Isles, the average depth is something less than 7000 feet. Beyond the Lesser Antilles there is nothing above the waves until we reach the Cape de Yerd Islands. When we first spread sail for that point, the plummet falls suddenly to a depth FORM OF THE SEA-BOTTOM. li of ] 6,500 feet or more, and rises as suddenly to little more than lo,000 feet. Again, it descends suddenly to 16,000 feet ; and then continues to mark a depth, varying by sudden changes, say from 16,000 to 10,000 feet, until near the Cape de Verd Islands, when the depth, even close inshore, is about 14,700 feet. These pinnacled isles rise to the height of 10,000 feet above the surface of the sea. Deep gulfs se- parate the one from the other; and a still deeper trench or canal, with almost perpendicular sides, brings the navigator to the African coast. We have mentioned the uncertainty of the results obtained by the plummet in ordinary circumstances ; and from the description we have given of this im- perfect instrument, it will be obvious that it affords no means for continuous or unbroken observation. It is necessary to make a fresh cast of the lead each time we want to sound the deep. We can only ob- tain, therefore, a series of points separated by inter- vals, whicli must be rendered as short as possible, in order that they may yield an approximately exact representation of the sea-bottom. In surveying any portion of land, with a view to its exact delineation, we can generally move freely over the surface itself that we are studying. The operations of geodesy give, with the utmost accuracy, the positions and the heights of as many 12 THE BOTTOM OF THE SEA. points as we desire. Suppose, however, that tlie conditions of our existence were such as to maintain Qs constantly at the height of 16,000 feet above the sea-level ? In that case, our survey of the land would be attended with the same degree of difficulty as our attempts to delineate the floor of the ocean. The highest mountains only would lift their summits into our atmosphere, and those alone we should be able to explore by the observation of actual contact. The plummet, or some analogous instrument, would have to be used for ascertaining the configuration of the less elevated regions. This is precisely our case in regard to the depths of the ocean. The regularity of its surface enables us to make use of it as a common point of departure from which to measure the relative heights of different parts of the terrestrial surface. If sufficient water existed to cover all the land, our globe would everywhere present the regular surface of a sphere, or nearly so. Although this is not the case, yet the great oceans, and all the seas communi- cating with them, have the same level. The pressure of the air is pretty constant on every point of the ocean-surface, and it is found to diminish in a certain ratio as we ascend in the atmosphere. It must be remembered that the bottom of the at- mospheric ocean rests on the surface of the watery ocean. If we suppose the whole mass of water to PRESSDHE OJi A Hi AND WATER. 13 coiisLst of a certain number of strata, it is obvious that the lowest of these must bear the weight of all above it, and is therefore uioi-e compressed than the next higher, and so on till we reach the surface. 80 \^ith the atmosphere. Its entire weight presses on tlie lowest stratum which touches the sea, and that weight of pressure in the torrid and temperate zones is marked by the barometer at 30 inches. If wo take the bai'ometer 87 feet above the level of the f.ea, it will mark the diminished pressure by 29-9, showing that it is one-tenth less. To show a diminu- tion of another tenth it would be necessary to go through a second space of more than 87 f( et, because the pressure of tht^ whole atmosphere is less by the height already attained. Thus, we shall find it necessary to rise higher and higher for every succes- sive tenth, until w^e reach a point when the pressure altogether ceases and is marked by 0. This would be at the top of the atmosphere. The reader will now understand how it is that a barometer serves to indicate the height of any part of the eaith's surface; indeed, it is the only possible means at our command in many cases for ascertaining height. A process analogous to this would be em- ployed with advantage to measure the depths of the sea. Suppose an instrument to be sunk in the water. The depth of water through which it had fallen 14 THE BOTTOM OF THE SEA. adding its pressure to that of the superincumbent air, and water being estimated at 1300 times the weight of air, it is plain that calculations which have been made relative to the atmosphere would, a fortiori, seem to be possible also relative to the ocean. An instrument so constructed as to indicate the pressure to which it had been subjected in the water would serve to complete or correct the results given by the sounding apparatus. Discordant indications would possibly afibrd evidence as to the direction and force of submarine currents. If we a VI to the imperfection of the processes themselves the difficulties of an accidental character which attend their application, we shall find but little reason for wonder that submarine orography is so little advanced. To make deep-sea soundings, a ship must be provided with a considerable amount of materiel of no use for any other purpose. A single operation during a voyage must employ several per- sons, and it could only be made in fair s^eather. In general, therefore, merchant-ships cannot be provi led with instruments and with hands to make deep-sea soundings; they would require cables or lines some four miles in length, and their crews would seldom be strong enough to deal with such heavy tackle. I'hen, the time spent in such op:^rations would occasion incal- culable loss to merchants and owners; and if the RESULTS OF EXTERIMENTS. J5 ?able parted, that ox[)onse would be added to the rest, and thus the lost apparatus could seldom be replaced. Evidently, experiments of this kind can only be made by Governments, or by commercial companies in- terested in their results. For example, the layin^^ of submarine telegraph cables has made it necessary in recent times to sound the ocean in various tracks. A-lmost every day sees some addition made to our knowledge in this way, and there can be no doubt that the multiplication of submarine telegraph lines will tend very greatly to hasten the time wlien we shall have an accurate idea of the form of the earth, and of the lesser accidents which affect its surface. Before the general form of the earth was ascer- tained, the depths of the ocean were the subject of the most extravagant suppositions. The writings of geographers abound in such expressions as that of " a bottomless and shoreless sea," to designate the Atlantic Ocean. The abandonment of such absurdi- ties is a necessary consequence of the facts known in the present day concerning the form and physical constitution of our planet. But other speculations, not less calculated to fill the imagination with an idea of grandeur, have taken their place. If the mass of water which covers about three-fourths of the solid crust of the globe is, after all, limited in quantity, what is the depth of the basins which contain it "^ 16 THE BOTTOM OF TEE SEA. The terrestiial shell is known to be irregularly broken, and its fragments, so to speak, piled on one another in gigantic masses of picturesque confusion — here heaved up into the air, there sunk from depth to deptli, with the waters of ocean gathered in their deepest gulfs. Plainly, if we add to the measurement of these depths beneath tlie sea that of the heights above, we shall obtain some useful data, and be enabled to form an approximate estimate of the stupendous forces in the interior of the globe which have produced such irregularities on its surface. # Before Maury made his appeal to the marine of all nations, something was known of the sea-bottom in the vicinity of coasts, and in the most frequented tracts ; but very little was apprehended of what lay under blue water. He called upon his brother sailors to commence a systematic observation of the winds and of meteoric phenomena, to note the marine cur- rents, and to sound the sea as they traversed it, if possible, every hundre 1 leagues. His call was heard, and heartily responded to. In a few years the North Atlantic, ploughed by the ships of all nations, had Ijeen sounded in so many points, that Maury was able, by combining the results obtained, to trace tlie con- figuration of the bottom of that ocean, and construct a chart analogous to a geographical tracing designed DEPTH OF BLUE WAIEU. 17 to indicate the surface of a cuuiitry in rcli(>,f. The curves are so drawn and .stipj)led as to show distinctly when the water is less than 6U00 feet deep, wlien it is less than 12,000 feet deep, when it is less than 1^,000 feet, and when its depth lies between that and 24,000 feet. The conclusion is that the average depth of blue water is not more than three or four miles, and that no reliable soundings have been made in water over five miles deep. This map (a reduced copy of which is given opposite p. 28) gives an idea, though an imperfect one, of tlie configura- tion of the floor of the North Atlantic Ocean. The Mediterranean, the Black Sea, the Baltic, and the seaboards of France and the British Isles, are much better known. These seas are shallow com- pared with the ocean, and the European marine has too great an interest in their study to neglect them. On the other hand, in the immense spaces left in the southern hemisphere by the continents and islands of Oceania the lead has rarely been thrown. The deep- sea basins which separate Asia and Africa from Australia and America have been but slightly ex- plored, chiefly because the navigator there sails fear- lessly before the wind, and dreads no rock or shoal which would make him desirous of knowing the depth of water on which he floats. Some observa c 18 THE BOTTOM OF THE SEA. tions have been made by the scientific voyages of observation sent out at the expense of States ; but except these we know of none that are available. The southern part of the Atlantic Ocean is equally a blank; and to make a sum of the whole matter, the greater part of the W( rid beneatli the sea is in- differently known. If we add to this fact, that the greater part of continents is desert or savage, traversed occasionally by a few hardy adventurers, we shall begin to see how vast are the lacunae still remaining in our study of the globe, and what an ample harvest of discovery may yet be reaped by the conscientious observers of nature. 3. Analogy between the Configuration of Continents, and that of tlie Bottom of the Sea — Equatorial Section of the Earth. Although the scientific results which we have al ready mentioned are incomplete, they are sufficient to prove that the greatest depth of the sea does not ex- ceed about five miles ; thus, that it is about equal to the height of the loftiest mountains. This depth has been plummed in all the great oceans^ and occa- sionally deeper soundings have been reported. The results, however, in the latter case have been obtained under circumstances w^hich do not command oui confidence. Such are the cases in which it would be eminently satisfactory to employ an instrument to SVDMAHINl': SCEXERY. VJ indicate tlie depth hy pressure, ms su^jijested in the foregoing section. The snbmarine soil in its configurations bears a close resemblance to tlie subaerial surface. The geo grapliical accidents, so to speak, are tlie same. There are plains, valleys, ravines, hills, escarpments, deserts of sand, immense deposits of mud, rolled stones, pic- turesque rocks, and even water-springs and vol- canoes. But while the bones of the earth beneath the waters, or the framework of the pictui-e, so closely resembles that of the soil above, the picture itself presents a very different aspect to the observer. In the first place, there is but scant light a little distance below the surface ; then, the vegetation is of a totally different character : the various algae float their long and brilliantly-coloured ribbons in the most graceful curves and modulations, or display their elegant tracery in fine and clearly-cut relief, like our mountain-trees. Animals, strange to our eyes, move slowly in an element which may be called gross when compared with our atmosphere. Springs of fresh water, instead of running upon the soil, are dispersed in vapour ; volcanic eruptions assume a peculiar chai-acter. Yet, with all these differences, the basin of the sea, in tlie eyes of the geometer, is in all essential respects similar to its shores. 20 THE BOTTOM OF THE SEA. Let us suppose the sea to be suddenly withdrawr from its basin, in order that we may the more clearly apprehend the conformation of the terrestrial crust as a whole, and thus see at a glance the unequal heights and depths which appear to us so considerable, but which, in reality, are very small when compared with the vast bulk of the planet. Let us, in short, sup- pose the earth to be reduced to the same physical condition as the moon, without an atmosphere and without water :* the eye would be arrested by vast ramparts formed of the earth's upheaved strata, and piled to a total height of some ten or eleven miles — the most gigantic of these picturesque eminences corresponding to the Old World, and having its culminating-point in the Himalayas. All around that vast rocky barrier Mould be seen a deep furrow separating it from the double gibbosity formed by the two Americas ; and taking our stand on the southern extremity of the latter continent, we should descry in the distance the summits of Australia and the neighbouring isles, and the ramparts of the great Austral continent, almost entirely buried under snow and ice. As the continents have their highest summits, so the oceans have their deepest gulfs, and these are often * Speaking from present appearances ; for, in fact, tliis point is not yet placed absolutelj^ beyond doubt. — Te. SUBMA HINE SCKNER Y 2 1 near neigbbour.s to each otlier. The Himalayan peaks are not far from the deepest part of theli.Jian Ocean ; the Kocky Mountains have for their near neighbour tlie deep gulf of tlie Northern Pacific; the Alleghanies are contiguous to the lowest depths of the North Atlantic ; and the towering bulk of Mont Blanc may be said to rise out of the deepest part of the wester/ Mediterranean basin. This remark is of general application, and we may add, that if on any ^oast the highest point of the upheaved surface almost equals the depth of the depression, that of the op- posite coast will be as far removed from it; as if the doublings and upliftings to which the actual configuration of the earth's crust is due were unsymmetrical, and had produced on the one coast a gentle declivity, on the other a steep hill. On the subaerial [)art of tiie earth there are vast plateaux or table-lands, and elevations of considerable altitude. Submarine pLiteaux are in like manner of frequent occurrence ; they separate two basins, the rocky edges of which are not sufficiently high to appear above the waters. In the Northern Atlantic Ocean, for example, a vast plateau stretches from Iceland to the Azores, and thence, southward and westward, to the Antilles or West Indies. The Azores correspond to volcanic peaks, rising from that chain of submarine mountains. Another plateau extends 2'i THE BOTTOM OF THE SEA. to the north, the east, and a little to the south of Newfoundland, terminating abruptly about the lati- tude of New York in a steep shore, along the escarp- ^nent of which flows the celebrated Gulf Stream. Near it, the orographic chart shows the centre of a basin where the sea is about five miles deep, compared with less than a third of that depth on the plateau. Tlie now familiar Telegraphic Plateau i'^ ' - latest dis- covery of this kind. It is a remcUxv. .o steppe, ex- tending from Cape Clear in Ireland to Cape Eace in Newfoundland, and upon it the mystic chain which unites the intelligence of the Old and the New World reposes in perfect security. Sometimes from the submarine plateau there spring numerous mountain-peaks, which lift their heads above the ocean, and rise to a considerable height in the atmosphere. Thus, an archipelago or cluster of islands consists of the culminating-points of mountain- chains, the bases of which are planted on submerged plains. If the Americas were covered with water to the depth of a mile, more or less, we should find in their places groups of islands corresponding to the Eocky Mountains, the Andes, the Brazilian Mountains, and to some })eaks of the Alleghanies and Antilles. The plummet would indicate the existence beneath tlie waters of great valleys separated by hills, by plateaux, or by mountains, for tiie most part with easy declivities; BOUNVXEi^S OF THE SKA-BOTTOM. 23 l)nt more abrn[)t near the prcsi'iit sliores of tlic coii- tiiieiit, especially on the western side, which overlooks the i^reat ocean. The bed of the sea cannot, with strict accuracy, be compared to the bed of a river. A section of the Mississippi, at Plaquemines for example, resembles a gutter. Neither does a lake of small extent present the means of a satisfactory comparison, however deep it may be. If we join the two opposite shores of a lake by a straight line, that line will be above the bottom of the lake, and will thus appear as a portion of the surface. This is not true of a sea, if it be of any con- sJit'i-able size. The earth is rounded in form, the free surface of the ocean is almost perfectly spherical ; and it is from that surface, as a starting-point, that the depth of the sea must be estimated. Drive a rectilinear tunnel through the earth from Paris to Newfoundland, as sketched in the annexed diagram, ?v^^ C-onrGaTiear I ^.*i»^ ""s?.«»p :>^^C^i^ Fig. 6. — Section of the Atlantic Ocean from Paris to Newfoundland. and it will be found that this tunnel nowhere encoun- ters the ocean. It will, in fact, pass far beneath it. 24 TBE BOTTOM OF THE SEA. Its entrance in Paris will neither be vertical nor li(irizontal. It will at on -e pass at a considerable depth under the English Channel and the ocenn, notwith- standing the comparatively great de^dli of thi' latter, and will reach the surface at Newfoundland obliquely as it had quitted Paris The same observation appliefj to all the great seas. The form of the earth being spherical, the bottom of the ocean, so far from being a cavity, is in its general outline convex. In order to give the reader an exact idea of the relative thickness of the solid crust of the earth, of its liquid covering, and of its gaseous atmosphere, we cannot do better than draw a section of the equator (fig. 7). In the centre, marked by the diagonal shading, is incandescent lire, of the chai-ac- ter of which we can only form a conception from the productions of volcauic eruptions. A solid crust of comparatively slight thickness envelopes the fluid kernel, and rests upon it like a rait upon the waves. When that internal sea of fire is agitated, its pal- pitations are revealed to us by startling results — in a word, by the breaking-up of that fragile crust upon which repose all our hopes. This solid covering is enveloped by a double at- mosphere. The lower (or aqueous) portion is not adapted to our mode of existence ; we can but float upon its surface. It is divided or broken up by the EQ UA TORI A L SECTION, 25 elevation of the earth info the hii^lier or gaseous poj-tion, which is alone appropriate to our nature. [The scale of depths is fifty times greater than that itf lentjths.} ¥.g. 7. — Equatoiial Section of the Eaith. In all prolability the thickn ss of the earth's 2fi THE BOTTOM OF THE SEA. crust is very far from being uniform. Its maximum cannot exceed, even if it reaches, sixty miles, or less than the sixtieth part of the earth's radius. In some places it is certainly very much less. In the neigh- bourhood of volcanoes, for example, it is so thin that combustible matters are ejected through the fissures in whicli these mountains abound. The greatest depth of the liquid envelope is probably less than six miles, and the gaseous at- mosphere, so far as it is respirable, can hardly be said to reach five miles in height. It is in this limited zone, of ten or twelve miles' thickness, that all the phenomena of life take place. How small is this space compared with the great mass of the globe; and, to follow out the contrast, what an atom is man compared with the immensity of the universe ! In the section (fig. 7) the bed of the great Equi- noctial Ocean, and that of the Indian Ocean, is marked by a dotted line, the data being insufficient to determine their depths with precision. This sec- tion cuts the northern part of South America, and touches the Pichincha volcano. It asses by the Galapagos Islands, which are separated from the continent by a deep arm of the sea. Traversing the middle of the Pacific Ocean, it cuts the archi pel ago of the Scarborough Isles ; and, farther on, the Moluccas, the island of Borneo; Sumatra, with one MAURY'S CHART. 91 of its volcai'oes ; Mount Opliir, directly opposite Picbincha — then the Indian Ocean, the immense plateau of Africa, tlie is!e of St. Thomas, and the Atlantic. In making this circuit, we are chiefly im- pressed by the fact that the external surface of the earth's crust is almost exactly represented by a circle. It is not without difficulty that we represent only a slightly undulating line, the inequalities being exaggerated in order that they may be at all perceptible. 4. Nortliern Atlantic Ocean — Chart of Maury. The Atlantic Ocean takes the form of a great canal, stretching directly from north to south, and trending to the east in its northern part. With Maury's Chart before us we shall find it comparatively easy to form an idea of the configuration of this ocean-bed. Tlie curves which indicate its varying level are drawn at such a distance from each other as to mark a thousand fathoms' difference in the relative depths. Thus all the points situated between the shores and the first curve vary in depth from to 1000 fatlioms, or 6000 feet; all the points between the first curve and the second augment in depth from 1000 to 2000 fathoms ; those between the second and third from 2000 to 3000 lathoms ; and those between the third 28 THE BOTTOM OF THE SEA, and fourth from 3000 to 4000 fathoms. Any greater depth is indicated by the blanks. On referring to the chart (iig. 8), it will be seen that a depth ex- ceeding 4000 fathoms is thus marked between New- foundland and the Bermuda Islands, in the track of the Gulf Stream. The plummet there descends to a depth of about 5000 fathoms, or nearly 30,000 feet. Westward of the Canary Islands is another deep point, the indication of the plummet being about 24,300 feet. A marked region of this ocean-bed, having a depth which varies from about 3000 to 4000 fathoms, ex- tends from the south of Newfoundland, rounds the Bermudas, and follows very nearly the direction of the American coast to the extreme latitude of Florida. It then winds south-east, keeping a certain distance from the Antilles, and terminating near the north- eastern extremjty of that archipelago. A second remarkable trough, separated from the last-mentioned by a submarine chain of mountains, extends like a long gutter from the north-west to the south-east, even beyond the equator. It is nearer to the Brazilian than to the African coast. Throughout these regions, which are the deepest in the Atlantic Ocean, the bottom exhibits great irregu- larity. The gulf deepens rapidly from the coast of America and the Antilles, but slopes gently from Europe and Africa. We observe, in fact, that the BOTTOM OF THE ATLAM'IC. 29 curves of the cliart approach very near to each other on the west, and are faiihest from each other on the east of the depression. Another noticeable feature is the immense plateau ranging almost parallel with the European and African coast, and dividing what may- be called the shelving side of the ocean-gnlf into two parts, for which reason it has been named by Maurj^ the "Middle Ground." It commences at Iceland, passes the Azores, and extends southward to the lati- tude of the Canary Islands ; then trends towards the Bermudas, and bulges southward to a point east of the Antilles. The depth of the sea at the southern termination of this plateau is marked in the chart by a curve, which indicates less than 2000 fathoms, or from 11,000 to 12,000 feet. This locality is identical with a part of the Grassy Sea. Between this middle ground and the coast of Europe a long valley extends north and south, and, at the Cape de Verd Islands, joins the depression w^hich is bounded by Africa, America, and the plateau or middle-ground just described. The depth of this valley is almost everywhere a little under 3000 fathoms, the exception being another spot, previously alluded to, west of the Canary Islands. In the northern end, westward from the British Isles, and even across the Middle Ground to Newfoundland, the depth is so uniform, that when soundings were 30 THE BOTTOM OF THE SEA. made for the purpose of laying a telegraphic cable between the Old World and the New, all this part of the ocean-bottom seemed as if it were purposely de- signed to form the bed of that wonderful conductor of thought. Hence the name of " Telegraphic Plateau " was given to it. For a considerable distance around the Azores the depth is less than 1000 fathoms. About halfway between the Azores and Newfoundland, there is also !i circumscribed region of comparatively slight depth — being marked in Maury's Chart as less than 2000 fathoms. In the whole of this route — that is to say, from Spain to the Azores, and from the Azores to Newfoundland — the depth nowhere exceeds 3000 fathoms. It has therefore appeared to present a suitable course for a telegraphic cable. The French line is laid midway between this plateau and the Enghsh cable of 1866. Along the coasts of Brazil and Guiana the sea be- comes rapidly shallower ; and as the great equatorial current which carries the waters from east to west is of vast breadth, we need not feel surprised to observe that it increases in swiftness as it approaches the coasts which confine its bed. There is then a descent or lower depth of the sea-bottom extending eastward from the Isthmus of Panama to St. Domingo, as if the rnsli of the carrent had washed out a o'ulf. This BOTrGER'S CHART. 31 is succeeded by the coinparatively shallow space of the Gulf of Mexico, and the sea in the neighbourhood of the Greater Antilles and the United States. A great extent of shallow sea is also to be observed extending from Nova Scotia to the east of the Great Bank of Newfoundland, and to the coast of Labrador. It is by this route, as all know, that the polar ice and icebergs descend towards the Gulf Stream, the warm current of which causes them to melt, and do- posit in the bed of the sea the debris of the land from which they had drifted away. 5. The Mediterranean and the Black Seas — Chart of Bottger. The Mediterranean and the Black Seas are of no great depth. The plummet seldom reaches 12,000 feet, and not more than half that depth in the greater part of their extent. The waters of the Mediter- ran;ean, however, cover many great valleys. The deepest is surrounded by the shores of Tripoli, Greece, and Italy. It is separated by a narrow chain of mountains from another great valley, which occupies the space bounded by the Grecian Archipelago, Asia Minor and the coasts of Syria and Egypt. Beginning at the Straits of Gibraltar, we find the submarine soil highest near the coasts of Spain and Morocco. At the western end of the strait, the depth 32 THE BOTTOM OF THE SEA. does not exceed 1000 or 1200 feet. As we advance eastward the depth augments rapidly, till it reaches nearly 12,000 feet south-east of Malaga. Soon, how- ever, the soil rises again. North of Melilla (a port on the coast of Morocco) it is about 1200 feet from the level of the sea, and forms a submarine mountain- chain, which bounds on the east a sort of little basin confined between the Sierra Nevada and the Marocco mountains, which are reunited under the sea in the Straits of Gibraltar. Continuing eastward, the explorer would descend into another valley almost as deep as that mentioned above, and communicating with that great depression by a neck of the chain which stretches under the waters from Oran to the Cape of Gades. Having surmounted this obstacle, we bend our steps north- east, and find ourselves in a great depression, which is narrow at first, but gradually spreading out becomes a great plain stretching to the Balearic Isles and the coasts of Sardinia and Algeria. We leave this great depression or basin by climbing a very steep ascent to the north-west. We then find ourselves upon an ex- tended plateau, from which rise numerous mountain- peaks. The principal of these form the Balearic Isles. The plateau is scarcely interrupted by Cartha- gena and Valencia, by the Balearic Isles, and by Corsica. It narrows, however, between these islands, THE MEDlTEliUANEAN liASINlS. 35 and we discover to the north anotlier irregular cavity occupying the space comprised between Majorca and the coast of Spain, and the Gulfs of Lyons and Genoa. The depth of the sea there does not exceed 6000 feet; and from this bottom there rises an isolated peak at the entrance of the Gujf of Lyons. To ascend from the Algerian depression eastward, it would be necessary to avoid the escarpments around Sardinia, and draw towards Tunis, in order to find an easier declivity. All around Sardinia and Corsica tlie depth of the sea is slight ; the basin formed by the Tyrrhenian Sea has nothing to boast of but two straight and elongated ravines- — the one extending from west to east, rounding the Lipari Islands : the other from north-west to south-east, running parallel to the Neapolitan coasts. The Bank Aventure and the Rocks of Skerki, near Tunis and Sicily, form an undulating plateau, over which we pass to the eastern basin of the Mediterra- nean. A steep descent leads from Malta, one of the culminating-points of the plateau, to the bottom of the depression which has for its boundaries Italy and Greece, Asiatic Turkey and Africa. The greatest depth is near Malta, where the plummet descends more than 14,000 feet, or about 2^ miles. No other spot in the Mediterranean is so deep as this. The mountains of Greece and Candia are prolonged 36 TEE BOTTOM OF TEE SEA. beneath the waters, and they divide into two nearly equal parts the great cavity we are now considering. The western part presents some steep slopes, but generally the bottom rises very gradually, till we come to the shallow waters of the coast of Africa on the one hand, and to those of the Adriatic on the other. M 'Z _o c _^ _^ H _^ ^.s^ « .-S (V ^ a> 1. 4i o '-2J o 0) ^1 o 1 1 1 1 § ^ o o 5 o is o o o O 2 o o o o t- o l> 00 O ;rS CO o iO o 'IZ 0-4 » 0-1 » 1-2 »> 0-8 ?> 0-1 51 2-9 1000-0 Sea-^^•ater, being thus composed, is considerat)ly 44 THE BOTTOM OF THE SEA. heavier than fresh- water of equal volume. Thus, a litre of fresh-water (nearly 1| pint) weighs less than a kilogramme (exactly 0^^998) at the temperature of 68° Fahrenheit ; the same volume of fresh-water under the same conditions would weigh V^'021. But the weight of sea-water, like its composition, is far from being constant ; it varies according to times and places, and even according to the depth from which it is taken. Southern sea-water is heavier than that of the northern hemisphere in the proportion of 1*0272 to 1 "02(32 of specific gravity, owing to the greater quantity of salt it contains. Off Cape Horn its specific gravity is 1*028, the heaviest known. The upper current of the Gulf Stream is lighter than the current below, because it is less saturated with salt ; but these facts will be further elucidated by-and-by. As the air, at whatever height we take a sample, is found to be of the same composition, an interesting question arises whether or not the sea partakes of this property ? Are the gases which enter into its com- position always in the same proportions? These questions are not easy to solve, because the enor- mous pressure exercised by a column of water many thousands of yards in depth causes extraordinary difficulties in the construction of the necessary ap- paratus. It must be remembered that it is essential to obtain the water at the required depth, and bring SEA-WATEB AT VARIOUS DEPTHS. 45 it to the surface with all that it contains in hermeti- cally-sealed vessels. It is not possible to emplo\ empty vessels, such as aie used for investigations into the (character of the atmosphere, contrived to open at the required depths. The water would either br, ak the vessels or filter through then). On their approaching the surface, any gases that had been subject to the enormous powers of compression of the superincumbent water, would dilate to an ex- tent which no vessel hermetically sealed could be expected to resist. Biot has, to some extent, over- come these difficulties in the following manner. He takes for his vessel a hollow cylinder of glass, closed at one end by a solid plate of metal, so as to resemble a pail. Like a pail also it has a handle, with a cord attached, by which it is let clown into the sea. This pail being open to the surrounding water, descends to any required depth without injury from the pressure of the water ; and whenever the operator pleases he pulls a second cord, attached to the bottom of the pail by means of an inverted handle, and this causes the vessel to tip over. By the same cord he draws it to the surface. It must now be observed that the metal bottom of the pail is double ; one of its parts being fixed, the other move- able like a piston, and capable of descending in the cylinder by its o\A'n weight when the vessel is i(; THE BOTTOM OF THE SEA. reversed. In the fixed bottom there is a small hole, furnished with a valve, which opens from the exterior to the interior, so that the water passes through and fills the space between the descending piston and the fixed bottom. This being done, the valve is closed by the action of a spring, and the water contained in the pail is isolated. If this water contained any quantity of compressed air, nothing would be able to resist its expansive power when it was drawn to the surface, and the pressure of the exterior water ceased to act. It would then burst the apparatus and escape. As a safeguard against this violence, a free issue is prepared, sufficient to serve for any possible expan- sion of the air in the water. In the fixed bottom there is a passage communicating with a bladder, which is empty and folded up when the apparatus is let down into the sea, but which receives whatever gas or air the water in the pail may disengage as it ascends, and thus returns to the surface more or less inflated. The operator then closes the stopcocks with which the passage of communication between the pail and the bladder is fitted ; and having sepa- rated the latter, he proceeds to measure and analyse the air contained in it. Having done this, he can study at his leisure the water enclosed in the pail, and whatever matter it holds in solution. SALTXESii OF TUE ISEA. 4 7 4 2. Varintions in llie Saltness of Sea-water. Water is so iiiueh the more heavy as it is more salt. It is not surprising, therefore, that the saltn* ss of the sea should increase with its depth. That increase is not indefinite, because water at a certain temperature can only hold in solution a given quantity of mineral matters. We must at once confess to our ignorani-e of tlie quantity of salts held in solution in the profound depths of the Ocean. With the apparatus of Biot we can, it is tru(", obtain Avater from great depths. Still, it is not possible to operate at distances of 20,000 or t-^0,000 icet from the surface ; or, if possible, the business is at once too costly and too diflicult to be often attempted. Eain and evaporation cause the saltness of the superficial waters of the sea to vary considerably. Evaporation increases, rain diminishes it. The effects due to these causes are, generally speaking, not very apparent ; but they are very observable when one of them predominates. If it rains frequently in certain regions, the saltness of the surface of the sea is slight in comparison with that of places u hen^ the clearness of the atmosphere favours evaporation. It is less at the equator than near the tropics. It is greatest at the 21st parallel of north latitude, and 48 THE BOTTOM OF THE SEA. the Kith of south latitude, in tlie Atkntie Ocean. Above these latitudes tlje saltness diminishes con- tinmally to the polar regions. On the other hand, we must not foriret that there exists near the equator a zone (tlie Equntorial Calm Belt), where the precipitation of the vajiour of water, in the form of rain, is almost incessant. To the north and south the trade-winds sweep the surface of the sea, and the atmosphere is clear, or only shadowed by clouds floating towards the region of rains. We also find, on approaching the poles, two zones of variable winds, where frequent tempests disturb the air, and cause abundant condensations. The relation of evaporation and rain to the saltness of the sea is thus made evident. In the polar regions the saltness of the sea is mo- dified by another cause not less active than the above — namely, the melting of the ice, accumulated like two vast cowls over the extremities of the earth. Every year, during the summer of eaf^h hemisphere, torrents of fresh-water are poured out towards the temperate regions. These torrents gradually mingle with the salt-water of the ocean, upon which they first flow along as a river on its bed ; and as a con- sequence of this, and the other active causes to wliich we have alluded, the saltness of the sea grows less at the surface in proportion as we approach the poles. EVAPOBATIOS OF THE SEA. 49 The water which the ocean loses by evaporation IS returned to it in full measure by rains and riviL'rs. It is not so, however, in the case of certain interior seas, completely isolated from the ocean, or only communicating with it by means of a narrow channel. The winds which blo.v upon such a sea may be de- spoiled of tlieir humidity by their passage across great continents, and the rivers themselves may not bring a sufficient tribute to supply tlie loss caused by a powerful evaporation ; or it may happen that the quantity of water returned by rains and rivers is exactly equal to that which is lost by evaporation ; or, finally, the supply may exceed the loss. In either case, the result, as regards the saltness of the sea, is obvious. In the first case its water will be saltei- than that of the ocean; in the second, it will be about the same ; in the third, less. If the interior sea communicates with the ocean, there will generally be a current in the channel which unites them. This current will float ships into the interior sea if that sea loses moie water than it receives; but it \\ill bear them to-vards the ocean if it receives more water than it lus ,;. The Mediterranean and the Red Sea both receive the waters of the ocean. The Black Sea and the IJaltic are, so to speak, too rich; they contribute their excess of water to the neighbouring seas. E 50 THE BOTTOM OF THE SEA. When the interior sea is the bottom of a basin without issue, either the supply of water hy means of rains and rivers iimst equal in volume that which is lost by evaporation, or the sea must gradually dry up. Tlie Caspian and the Dead 8eas are both examples in point. The first is surrounded by ealt steppes, where it is easy to discover traces of the recent exist- ence of the waters. Its level is above 100 feet below that of the Black Sea, and it is constantly decreasing in extent, and is very salt. The Dead Sea is at pre- sent about 1400 feet below the level of the Eed Sea ; yet travellers have recognised between the two seas the dried-up bed of a river, which, through causes not yet ascertained, has ceased to unite them. Since that epoch, the Dead Sea has not received sufficient water from the Jordan to supply the loss ocasioued by eva- poration ; its level has consequently sunk and its salt- ness has proportionately increased, until an equilibrium has been established between the supply and loss. There are many salt lakes, both in the Old World and the New, which owe their saltness entirely to the rivers which flow into them. The delivery of water is increased, and the lakes overflow ; it is diminished, the lake retires, and its saltness increases. When the supply of water is quite insufficient to compensate for evaporation, the lake dries up, and in its place is seen a valley covered with a bed of salt. MATERIALS WASHED IS BY RIVERS. 5j The composition ol sen-water varies most in the neif^hbourhoocl of tlie coasts. It is only at a con- siderable distance Iroiii its embouchure that the water of a river mixes with that of the ocean, and the one is often distinguished from the other by a well-defined line. This phenomenon is most striking at the embouchure of the Mississippi. The " Father of AVaters " rolls into the sea laden with yellow mud, which forms a shifting promontory in the midst of the dark waters of the Mexican Gulf. "Suddenly," says a recent traveller,* "it seemed to me tliat the colour of the water had changed : the deep blue had become yellow, and the distinc- tion between them was marl^ed by a line as straight as if drawn with a cord, extending from east to west. Northward, a darkish coast-line, half con- cealed by mist, indicated the direction of the land : we were floating on the waters of the Mississippi. Soon the speed of the ship was slackened, she was scarcely able to make way ; all at once she stopped, her keel was fast in the mu;l." Another cause sometimes tends to diminish tlie saltness of tlie superficial waters near the coasts. Rain which falls upon the steep or sloping shores at once finds its way into the sea. In this case the waves and currents combine to mingle the fresh * M. Elisee Reclus : Fragment d'un Voyage a la NouveUe-Orlean» 62 THJi: BOTTOM Oi THE SEA. and ihe salt water togethei", and the accidental anomaly is soon lost to observation. Fresh-water is contributed even by the bottom of the sea itself. It is true the phenomenon of sub- marine springs is of rare occurrence, yet some re- markable instances are known, and many others may have escaped notice. In some places, generally near tlie shore, the sea may be seen to bubble, and yet no gas is disengaged. The movement is occa- sionally so pronounced that the surface of the sea swells as with a wave ; and if, in such a case, we test the water, it will be found to b(3 less salt than usual. If the sample be taken from near the bottom, it will prove to be nearly fresh ; indeed, if the source be abundant, it will be found to be quite fresh. The effect of these springs, however, is not traceable to any considerable distance, and as they are always near the shore, we can only regard them, in con- nection with our subject, as objects of curiosity. 3. Variations observed in the Gases contained in Sea-water. Sea-water not only contains salts, but gases. Air penetrates into the sea, as water penetrates into the atmosphere, in the state of vapour. Thus a kind of exchange or reciprocity of action is established, and in both cases a sort of refinement or purification is efiected GAiSES ly THE SEA, n'A Water converted into vapour is disburdened of its salts ; air contained in water becomes ri(;her in oxygen. This gas plays a most important part in oceanic phenomena. Without it no living thing could exist in thi' sea. Except for it, even those beautiful algae, whose long and brilliantly-coloured ribbons are floated in undulating curves by the marine currents, uould no longer charm the eye. The whole race of polypi would cease to construct their stony habi- tations, which are so much admired by the lovers of nature. The deeper we penetrate into the ocean the more abundant are the gases. The increase of carbonic acid gas with the increasing depth is especially re- markable; and lience the gaseous mixture found in the dreper parts of the sea is less suitable for re- spiration than that which is nearer the surface. It is further to be observed that the renewal of gases in deep water is effected with much less facility ; and this may be regarded as one of the causes which tend to prevent the existence of organised beings at a great depth. As aerial plants and animals are confined to the lower strata of the atmosphere, so marine plants and animals are ^'on- demned to remain near tlie surface of the waters, com- paratively speaking. Thus, the living beings which flourish on our globe are confined to a very limited 54 THE BOTTOM OF THE SEA. Stratum of air and water, and they reach their maxi- mum development where the two atmospheres meet* When a volcanic eruption takes place in the sea, the composition of the gases contained in the water is necessarily changed in the neighbourhood of the volcano by the subterranean emanations. Some seas, like the Caspian, are literally poisoned by volcanic products, and this to such a degree that it is hardly possible to live near them. A bird can- not hover above their waters without the risk oi* perishing from their deadly influence.! In the great oceans the gases produced by volcanic eruptions are reduced to insignificant proportions by the action of the marine currents. * Notwitli standing the general truth there is in this statement, organised creatures have recently been discovered in much gnattr depths than had been anticipated. — Tr. t This was for a long time the popular notion concerning the Dead Sea, The fact is now known to be otherwise. Mr. Tristram, in that chapter of hs interesting journal where he describes "the Dead Sea shore," ment'ons having seen a fine brown-necked raven, which flew quite across the lake, and a kingfisher actually sitting on a dead bough in the water. Many gulls were also fishing in their customary manner ; small flocks of pocLard ducks skimmed the surface, and close along th(j shore were dunlins, redshanks, and wagtails, and one specime;i of the desert whtatcur. At tlie same time, lie says, " it is quite cert, in that no form of either vertebrate or molluscous life can exist for more than a very short time in the sea itself, and that all t! at enti r it are almost immediately poisoned and edited down," — Tr. ANIMAL DEBRIS IN THE HE A. 55 4. Solid Bodied in the Sea — Phosphorescence. The sea holds in suspension a great variety of solid matters. In the first rank are fish, which float in the liquid element as birds in the air, whilst the other living creatures of the ocean are under the necessity of finding a point of support on the submarine soil. The number of creatures float- ing in the water is enormous. Many species of them congregate in shoals, which have sometimes been known to cover hundreds of square leagues of surface, and extend several hundreds of feet in thickness or depth. It is not, however, to the natural history of animals that our attention is now called. Our subject is the sea-bottom, and it is only so far as any creature lives on the submarine soil, or leaves its spoils there, that we owe it any special regard. One passing observation may be made. It seems certain that such immense shoals of living beings must vitiate the aqueous atmosphere in which they float, just as any other similar congregation of men or animals would affect the surface of the earth and the air they breathe. Their dehris must un- doubtedly be reckoned among the agents by which the basin of the sea is more or less modified. The spawn of fish existing in such numbers forms enormous banks, and it is to this cause that thf^ 50 THE BOTTOM OF THE SEA. phosphorescence of the sea is sometimes due. M. de Tessan has observed a phenomenon of this kind at Simon's Town, Cape of Good Hope : — "On the 10th of April, in the evening, the sea, in the roadstead of Simon's Town, presented an ex- traordinary phosphorescence of the most vivid cliaracter. At whatever points tlie phosphorescence was greatest, the water was coloured on the surface as red as blood, and it contained such an immense quantity of little globules that it had the consistency of a syrup. A bucket of water taken up at one of tliese points, and filtered through a piece of linen, left on the filter a mass of globules greater in volume than the water that had passed throngh : in other words, the globules constituted more than half of the whole quantity of sea-water taken up in the buck'et. Yiew^ed through a magnifying-glass, these globules presented the appearance of little transparent and inflated bladder.-^, having on their surface a black point, surrounded with equally black radiating striae. They had a very perceptible odour of the sea, and most probably they were the spawn of fish. Thus isolated fi-om the water, they were highly phos- phorescent; the least agitation, the least contact made them throw out a vivid greenish light, whilst the water that had been filtered away from them had completely lost the property of becoming phos- Fig. 13. — Phosphorescent Sea at Simon's Town, Cape of Good Hope. fHOSFUORESCESClJ OF SVA WN. 5EA. i'S which it protects will, therefore, soon indicate an equilibrium of temperature between itself and the surrounding water. The temperature of the deeper waters is not the same as that of the superficial mass. It is therefore 'lecessary to employ instruments, so constructed as to keep a record of the extreme temperatures through which they are passed. To effect this, P^ron en- closed the instrument in a tube made of a substance that \Aas a bad conductor of heat. This apparatus, being immersed for a sufficiently long time, at lengtli acquired the temperature of the water that surrounde I it, and being quickly withdrawn, there was no time for the heat to escape before the indication was read off. Bunten has attained the same en«1, by inventing what he calls the '* Thermometer Plunger." The instru- ment is put into a tube closed by a valve, which opens from the exterior to the interior ; thus allowing the water of the sea to enter, but preventing it from re- turning when the apparatus is withdrawn. The ther- mometer, therefore, is brought to the surface sur- rounded with sea-water; but it is easy to see that we cannot be sure of the depth from which the water is taken, as in the case of Peron's instrument. Finally, the thermometer is not protected from the pressure of the v\ater. Bunten's Plunger, therefore, is not available for deep thermometric soundings. 70 THE BOTTOM OF THE SEA. Perhaps the best metho 1 discovered up to the pre- sent time consists in enclosing one of Walferdin's metastatic thermometers in a strong box of wrought- iron or copper, noting on the return of the instrument the lowest temperature that it has marked. Some- times, however, the box will be found crushed. 7. DimiuisheJ Temperatuie of the Sea in proportion to the Deptii — Irregularities introduced in this law by the influence of Sub- m.iriiie Currents -Temperature at the Bottom of the Ocean constant and uniform— Principal causes of Subm trine Currents. The temperature of the atmosphere diminishes m the degree that we ascend above the level of the sea ; that of the sea generally diminishes in the degree that we descend below its surface. It varies but little from day to night, and even from season to season. At no great depth it ceases to vary at all. The surface is hottest at the equator; it is frozen at the poles. Between these extreme latitudes there is a succession of diminishing temperatures, but they are far from decreasing in regular gradation from the ecjuator to the poles. The water is influenced by marine currents, which have the effect of masking the otherwise regular law of decrease. The law which varies the temperature according to the depth is also complicated by accidental causes. Often marine currents flow one above another — the TKMPIJtATUliE OF THE SEA. 7 J one being cold, the otlier hot ; their directions also cross each other in a thousand ways. There may thus be many successive beds or strata of currents, their density in each case being the greater in proportion to the depth from the surface at which they are situ- ated. As a proof that such different currents really exist, it may suffice to mention the suddenness with which the thermometer varies after passing thiough a certain depth of water, and tlien continues constant while the plummet descends through a lower bed. Thermometric soundings have marked a tempera- ture of 41^ Fahr. in the latitude of 43° and 37° under the equator, at the same depth, of somewhat less than 6,000 feet. This agrees with the direction of the sub- marine currents, coming resjjectively from the poles and from tlie equator. In the torrid zone between 33° and 34° Fahr. have been indicated at a depth ot 12,000 feet, whilst the temperature at the surface was about 80° Fahr. This result will be thought less sur- prising if we bear in mind that while fresh-water attains its maximum density at 39° 5' j: j... ., average sea-water does not arrive at its degree of maximum density until it passes its freezing-point (27° IJ') and reaches the temperature of 25° 6. As sea- water is not easily penetrated by the rays of the sun, it keeps pretty nearly at the temperature of the locality where it has been detained for any 72 THE BOTTOM OF THE SEA. length of time. Thii^ the play of the polar waters makes itself known to the mariner by a fall in the temperature of the sea, and the eqnatorial currents carry with them into the arctic zones a warm and grateful reminiscence of the sunny climes from which they have descended. In general, the density of a current is in inverse proportion to its degree of heat, and accordingly, overlying currents show a decreasing temperature according to their depth. But in the polar seas this is not so. The temperature there increases with the depth, within certain limits, and thus assists in fusing the lower part of the ice. To account for this anomaly, snow and ice are bad conductors of heat. Farmers and gardeners are well acquainted with the fact that a covering of snow keeps the earth warm in winter. The effect of ice in the arctic regions is similar. It has been proved by thermo metric observations that, at a surface temperature of 52° below zero (Fahr.), the water under a bed of ice thiity-two feet thick re- mained relatively hot, its temperature not liaving descended below 28° 4' Fahr. Thus sea-water is hottest near the surface in the neiglibourhood of the equator, while in the arctic regions it is hottest at a certain depth, and coldest in its upper stratum. The temperature of the sea-bottom is, however, uniform over all the world, and differs TEMrERATi'RE OF TILE MEUITEUIIANEAN. 73 little from 32^ Fahr., or five degress above its freezing- [)oiiit. In the case of landlocked seas there is not this great difference between the temperature of the surface and of the lower strata. The Mediterranean, for example, receives the surface- w^aters of the ocean through the Straits of Gibraltar, whilst its deeper waters flow out- wards.* Consequently, it is the heated water of the ocean wdiich penetrates into this interior sea; and the action of the sun being upon a closed basin, so to speak, and by far more constant than upon tlie ocean, which is traversed by the polar w aters rushing in a mighty torrent to sun themselves in the toi'rid zone, the bottom of the "Mediterranean cannot possibly be so cold as the bottom of the ocean itself. The Red Sea presents the same phenomena, in this respect, as the Mediterranean. The currents of Babelmandeb are analagous to those of Gibraltar. The Eed Sea is one of the hottest expanses of water on the globe. Life pulsates in every corner and recess of it, and * A very curious incident first suggested the existence of a sub- marine current in the Straits of Gibraltar. A corsair brig sunk in sight of Ceuta, and disappeared. At thio point the current runs very strong, and, of eouise, from we.^t to ea.'J called a geogenic hasiii, to distinguish it from a geograi^ldc basin. Thus, the basins of th<^ Rhone, the Ebro, tiie Arno, tlie Tiber, and several other rivers, all com- bine to form one vast geogenic basin. The Tyrrhe- nian Sea is one of the divisions of this great basin, the Gulf of Lyons is another, that of Genoa a third. 2. Action of Waves upon the Coasts — Destruction of Ruck-bound Shores by the Sea — Pierced Rocks — Silting-up of Shallow Waters by Marine Alluvium. In the case of a steep shore the erosive action of the sea is considerable. It beats against the rocky barrier with all its force. The base of the cliff, in- cessantly attacked by the waves, is of course eaten away with a rapidity proportioned to the ease with which the matter of the rock can be disintegrated. The upper part of the cliffy though not subjected to the direct action of the waves, falls forward, and occasionally forms deep rocky caverns such as we see at Bonifacio. At length the superincumbent and tottering mass falls into the sea. If the depth be great, or the current strong, the accumulated debris is swept away, and the action of the waves against the broken cliff is continued with undiminished in- tensity. In this manner entire promontories have been destroyed; even within th;^ historic pv-riod, the 90 THE BOTTOM OF THE SEA. Straits of Gibraltar have been enlarged by this pro- cess. If, on the other hand, the depth be slight at the base of the cliff, the force of the waves is broken by the opposing rampart of lallen stones, the shore is preserved from destruction, and it is only at some Fig. 17 — Waves breaking against a Kock-bound Coast. distance from the self-formed talus that the rolled stones are, in the course of ages, carried away by the currents of the ocean. The foot of the cliff marks the level of the sea. If this level be chang;ed from anv cause, the cliff will FOh'.MATloy OF CAVERNS. !)1 be tormcci anew in accordance with it. In seas of little extent, sndi as the Mediterranean or Caspian, and at those points of the ocean where the ti(hil elevation is bat small, the cliff will consist of but one simple escarpment. When, liowever, the differ- enae between the level of high and low water is considerable, as in the English Channel and other narrow passages, there will be found a second cliff corresponding with the level of low-water. Many marine caverns have been formed by the erosive action of the sea upon massive beds of basalt. Tliis rock is the product of ancient volcanic eruptions, the volcanic matter having separated itself into prismatic columns in the process of cool- ing. The t-ea, by its reiterated assaults through a long lapse of time, causes the lower beds of basalt, which are the most exposed to the lury of the waves, to yield first. Thus are formed caves, or sometimes extended galleries and halls, of which the Cave of Fingal is a beautiful example. The erosive action of waves is slower when the rock is in horizontal beds. In such cases the water rolls over the inclined surface until its course is arrested, and in its return it breaks the force of the next approaching wave. A striking effect of the erosive action of the sea is buown in the phenomenon, so frequently met witli, ai 92 THE BOTTOM OF THE SEA. pierced rocks. Sometimes they are found isolated in mid-ocean ; sometimes they are united to the land, or only separated by narrow, and perhaps tortuous, channels. Let us hear what M. de Tessan has to say, in the work already quoted, of the manner in which waves act upon such rocks : — "Lat. 25° 0-9' N".; long. 120° 76' W.— We have passed very near the Alijos Kocks, which are "still marked as doubtful in some charts. The highest of them rises about 150 I'eet above the sea. It is pierced through in the direction from south-east to north-west. This phenomenon of pierced rocks oc- curs most often when the rocks are composed of superimposed beds, of no great thickness, and not well compacted one with another, it is to be ex- plained by the action of the billows ; in fact, their most destructive effect is produced upon the perpen- dicular face of the rock, about the middle of its elevation, and in the direction in which the waves strike against it. The rock of course has a tendency to crumble away at that point more than elsewhere, and if its composition be such that it cannot resist the incessant shock of the waves, an excavation necessarily results. The hollow, once formed, be- comes itself the cause of an increased destructive effect on the action of the waves. Gliding along the sides of the excavation, thev strike with re- PIERCED ROCKS. On doubled speed upon its bottom, where the former debris of the rock, dashed about with immense force, helps also to break up the rock and make fresh debris. In this way the depth of the excavation increases, its sides are enlarged, and at last dayliglit Fig. 18. — Rocks worn through by tlie Waves, is let in from the other side. To produce this result, however, the rock must not be too thick, because there is obviously a limit in the depth of the exca- vation at which the wave loses its force." 94 THE BOTTOM OF THE SEA. If the sea struggles victoriously against the land when the latter opposes to it some formidable ob- stacle, its efforts fail, its force, so to speak, expires when there is no such resistance. It batters down the rock-bound shore with resistless force ; it flows harmlessly over low and sandy flats. Further, the debris of the stubborn rock serves to strengthen the shifting sands, and to renew the dunes which the winds scatter in light clouds of dust. The tidal wave spreads out over the level shore, until it has lost all its speed, and when it retires it leaves behind it on the sands all the materials which it had pushed before it as it came in fiom the sea. 3. Deposits in Mid-ocean, and Deposits on the Coasts— Importance to Geologists of Coafrt Deposits as data for fixing the limits of Ancient Seas — Deposits of the French Seas. It is only from a large number of skilful soundings that we have been able to ascertain the character ot submarine deposits. Soundings at great depths generally indicate the presence of the debris of rocks in a state of minute subdivision. To take a single example : at a point seventy leagues south of the Aleutian Isles, and at a depth of 9000 feet, we detect the presence of fine sand and mud. The deeper parts of the ocean occur at too great a distance from the coasts for the larger and heavier DEVOSnS IN DEfJP WATKR. 0:. biibstances to be carried clown into those profound gulfs by the marine currents. If the remains of animals and plants fall directly from the surface into such depths, they preserve their forms, however delicate, because the calm which reigns in these still, mysterious regions allows them to rest undisturbed for an indefinite period in the spot they first touch. Thus the accumulation of materials is a slow and gentle process. They repose quietly in horizontal and homogeneous beds, and, as a consequence, produce compact and finely-graine 1 rocks. On the coasts, and in those parts of the sea which ai'e of slight depth, we generally find stones and bodies too large to be carried away by the currents. The materials thus accumulated are subjected to the continual action of the water. They lose their angles, and become rounded or oval in form. They are in- cessantly worn away and incessantly renewed. The result is that coast deposits have neither the same regularity nor the same consistency as those of the deeper seas. They do not exhibit, like the latter, a compact structure, nor do the substances which com- pose them display sharp angles and well-preserved forms. The action of the waves extends to an inconsider- able depth from the surface, especially in all ordinary times when there is no extreme agitation. The y6 THE BOTTOM OF THE SEA. littoral deposits are, therefore, of comparatively slight amount when regarded as to their quantity merely, but theoretically they are of the greatest importance. An exact knowledge of their character often enables the physicist to determine the oscilla- tions of the sea, how it has retired from the land or encroached upon it, and consequently to what extent the terrestrial crust has been affected. The follow- ing details are borrowed from a work presented to the French Institute, some two years ago, by M. Delesse, and which may be described as a complete study of the deposits which are being formed in our time upon the coasts of France, and of the re- lations they bear to currents and marine animals, but more particularly to the nature of the rocks which form the shore. This littoral deposit presents a. mineralogic com- position of considerable variety is a level corres- ponding to that of high-tide, because it includes the debris of the neighbouring cliffs. At the level of low tide, on the shores of the Ocean, it is much more uniform, and even exhibits a constant character to a great extent. Where we find this to be the case, we may be sure that, whatever be the character of the rocks which concur to form the deposit, the sea is not slow to destroy them. The minerals we dis- cover are those which offer considerable resistance to IJ VTOHAL DEPOSITS. 9'i the action of the sea, owing to tlieir luirdiiess or tin unalterable nature of their composition. The most common of all minerals in tlie littonil deposit of France, at the level of low-tide, is trans- parent qnartz. It is distribnted in such profusion that the deposit is sometimes almost entirely com- posed of it. This is to be acfonnted for by its extreme hardness and its abundance in th« cliffs. The clays are found in the deposit at the botto.m of gulfs and retired creeks ; tiiey are carried away in the form of mud, and settle down when the sea is calm and deep. In some cases wliere beds of clay or schist abound on a coast (as at Honfleur), the pro- portion of clay contained in the littoral deposit is very great. Carbonate of lime or chalk is found in very variable proportions, and is derived from calcareous rocks and the remains of molluscs. In the Mediter- ranean il is most abundant when the cliffs are com- posed of calcareous rock, as at Nice and Marseilles. Its fragments are always well-rounded. On the shores of the Ocean, the littoral deposit of lime is small, because the movement caused by the tides dissolves and disposes of it very rapidly even when it is strong or compact. An instance of this may be obsersed between Havre and Dunkirk, or, better still, at the foot of the Lower Pyrenees. It may even happen 9.S THE BOTTOM OF THE ^EA that the deposit formed on a chalky shore does not rontain a trace of calcareous debris. On the Atlantic coasts of France the carbonate of lime found in the littoral deposit comes almost entirely from the shells of molluscs of the existing period. It is composed of angular or slightly-rounded fragments, and it resists destruction much better than the most com- pact limestone. On the other hand, we may see a coast without limestone, like that of Brittany, present nevertheless a rich littoral c-eposit of carbonate of lime, exclusively derived from the debris of shells. As we proceed to a distance from the shore, the depth of the water increases, and the marine deposit changes its physical and chemical properties. Thus, the proportion of carbonate of lime grows larger, and its particles at the same time diminish in size. On the whole, these researches demonstrate that the littoral deposit varies in its character with the hydrographic basin to which it appertains, and with the coasts, above and below the water, upon which it is formed ; in the Ocean, on the contrary, it remains pretty con- stantly the same over a vast extent of surace.^ * Delesse : Becherches sur le depot littoral de la France (Compteji Rendus de I'lnstitnt de France, Number for January 28, 18G7, pp. 165 et seq.) Di:nRTS OF G LAC I KRIS. L»9 4. Transport and Deposit of I^ocks by Floiitiug Ice. When fragments of rock are transported by the water, it carries the smaller and lighter sand to a greater distance than the heavier, this again to a greater distance tlian stones or pebbles, and these latter, of course, much forther than great blocks of stone. These materials of the earth's crust find also a powerful and majestic means of transport in floating ice ; but it carries its load without discrimination, and deposits fragments of all sizes aiid of every de- scription that may chance to be imbedded in its mass. During winter we see our rivers covered with a sheet of ice : the spring returns, the frozen surface is melted, and masses of ice float seaward in dis- ordered heaps. This phenomenon constitutes an annual break-up. Where the water touches the sliore stojies and earth become imbedded in its solidified mass. If the river be completely frozen in its whole depth (which happens sometimes in northern coun- tries), its bed as well as its shores will load the ice with debris, which is thus transported to a distance. This phenomenon, which we witness once a year, is produced on a grand scale in the polar seas. On those inhospitable shores the rivers of ice, called glaciei's, glide down from, mountain heights into the sea, and carrv on their surface, as well a* m tlieii 100 THE BOTTOM OF THE SEA. interior, massive fragments of rock, gravel, and dirt. Sometimes a mass is detached from the glacier, and, floating away into the open sea, is impelled by the marine currents and the winds towards the equator. On the passage, the shock of one such mass striking against another, the action of the waves, and the melting of the surface of the ice, destroy the mass, Fig. 19. — Section of the Sea and the Sea-bottom in the Track of Icebergs between Greenland and Newfoundland. and the debris which it carries drops from time to time to the bottom of the water. In this manner, icebergs perform their part in the work of sedi- mentation. The deposits formed by icebergs attain in course of time to a great thickness The Bank of New- foundland appears to have been formed in this way. I'OLAJi WE-FIh'LDti. 101 Every year the cold currents flowing from Baffin's Hay (which in strictness sliouhl bo called a sea) visit Xiiwfoundland with their imposing freiglit of ice- H Ids and frozen mountains. On approaching that island they encounter the Gulf Stream, and the frozen masses gradually disappear, being eaten away by the waters, the heat of which undermines them. The earth and fragments of rock which thi^y carry fall to the bottom of the sea. Every year the warmer cui-rent of the Gulf Stream arrests these masses of ice at the same point of their track, and causes them to break up and disappear. A simple current of water opposes to them an im- passable barrier. The debris accumulates year after year in the neighbourln)od of Newfoundland without ever enterino^ into the Mexican current. VVliat a^jes must it have required for this submarine deposit to have filled up an abyss to a height of from 20,000 to 30,000 feet ! Thus the influence of the polar ice-fields is so- great as to modify, in course of time, the form of the earth's surface. This too occurs over a large ex- tent of tlie globe, seeing that the ice in the northern hemisphere actually attains to the lOth degree of latitude, and in the southern hemisphere to the liJth degree. 102 THE BOTTOM OF THE SEA i). Water-springs in the Earth — Funnels or Wells of the Jura-^ The A veil of the South of France— Katavotron — Sinkholes- Geysers — Submarine Springs — Origin of Oolitic Formations. Water spread on the earth penetrates to a certain distance below the surface. It sinks through sandy places, cultivated lands of all kinds, and even through the hardest rocks. Fissures are produced in the latter by the influence of temperature, and by these little channels the water descends into the interior of the earth's crust. Limestones favour a cavernous structure, and conceal gulfs or pits wbicli are known by diiferent names in different countrit^s. These are the Funnels or Wells of the Jura, the Sinkholes of Amen ( a, the Katavotron of Greece, and tlie Aveii of the South of France. Such gulfs may sometimes be found in the course of rivers. In a word, by whatever means of absorption, the water finds its way into the ter- restrial crust, and that to a very considerable extent. After an interval, more or less prolonged, it returns to the surface. Springs, fountains, artesian- wells, geysers, are thus originated. G-eysers are intermittent springs of boiling water, observed for the first time in Iceland, where the phenomenon is attended by remarkable circumstances.* 'I'he return of the water to the surface takes place * See "Iceland: its Scenes and Sagas," by S. Baring-Gould. SrBMA RIXE SJ'Itl.WS. 103 under tne sea no less than on continents, as proved by numerous observations of submarine springs of fresh-water. Many such have been remarked on tlie Mediterranean littoral. According to M. de Ville- neuve-Flayosc, those ^ wliicii we find between Perpig- nan and Spezzia, at a distance more or 1( ss gieat fi'om Fig. 20. — Can.«e of Submarine Sprincrs {aa') ?ea Water; (bb) Kre-h Water; (^cc') ImpeiTaeable Strata, (t/c?) a Permeable Stratum in which the Fresh Water tlows the shore, deliver some 50 cubic metres every second, which is about one-third of the quantity of water delivered by the Seine in the same time. In the Gulf of Spezzia, at tlie distance of 60 or 70 yards from the shore, we see a kind of swelling in the sea* it extends over a space about 80 foot 104 TEE BOTTOM OF THE SEA. m diameter, and is something less than six inches in height. When the sea is calm it is easy to see ver- tical jets of water springing from tbe bottom. This water is found to be fresh, and it comes from a sub- marine spring. Its superior lightness causes it to reach the surface of the sea before the salt-water lias time to affect it. At some distance from the embouchure of the Ga- laso, in the Gulf of Tarentum, there springs from the bottom of the sea a jet of fresh-water so powerful that it can be procured without mixture with the salt- water. A similar jet exists in the famous salt-pool of Thau, near Cette (on the Mediterranean coast of France) ; here the fresh-water rises so rapidly that it produces waves. What may be called a true subterranean river de- bouches under the sea near Ragusa. There are sweet- water springs in the ports of Gattaro and Aulona, near the embouchure of the Acheron, in the midst of the sea ; over a space of 40 feet in diameter fresh- water is thrown up abundantly with great force. This is probably the same spring of which Paiisauias speaks. A stream of fresh-water springs from the bottom of the sea near Tortosa, on the coast of Syria. Its force is so great that the sw^eet water can be taken without mixture with the salt. Pliny speaks of a >imilar phenomenon near Arcadus. SUBMAlilSE SrRlNGS. 105 The Gulf of Argos suppli<^s an example of a ve)\- abundant source of fresli-water named Anavolco, and situate 1 between Kiveri and Astros. Ancient writers affirm, though this may be a little uncertain, that it has been in activity some 1700 years. Colonel Leake, a traveller remarkable for his minute observa- tion, informs ns tliat the column of fresh-water appears to be not less than 50 feet in diameter. Wiien the atmosphere was calm he observed tlmt the water rose with such force from the bottom of the sea as to swell the surface, and agitate it in concentric circles to a distance of some hundreds of feet. He attributed this to the embouchure of a subterranean river at the bottom of the sea. This phenomenon may, in a certain measure, be compared with that of artesian- wells, now so familiar to us. The water fif.ds its way into the eartli by fil- tration through certain permeable strata. These are so enclosed by beds of clay, or other matters not per- meable, that they form conduits which accidentally terminate beneath the sea. The fresh- water running in these natural conduits is lighter than salt-water. If it exists in sufficient quantity to prevent its being mixed completely with the latter, it rises t'j the sur- face on the same principle that oil tloats on the surface of ordinary water. It is not surprising, therefore, that we should find ion THE BOTTOM OF THE SEA, in all seas submarine springs of fresh-water. Hum- boldt observed one, two or three leagues southward from Cuba, rising with such force that the smaller craft could not approach without risk. Ships supply themselves witli this water, and find it sweeter than water taken from other places of greater depth. Water that has been in the earth hold's in solution a certain amount of salts, proportioned to the time it has been detained underground, and to the de|)th and consequently increased temperature it may have attained. On returning to the surface, whether it be on the land or beneath the sea, it makes some slight deposit of the salt it holds in solution. Of course the quantity is not greater than is usually to be tound in what is called fresh-water, yet the deposit, accumu- lated through a long period of time, assists in the work of sedimentation, and thus modifies the bottom of the sea. To express by one word the character in common of all the deposits thus formed, they may be called "Geyserian." This appellation has been given to them by M. Alexandre Vezian, from the phenomenon which may be considered typical. Springs charged with stony matter, that is to say, petrifying springs, are the cause of deposits after their kind, but differing considerably according as the water in which they rise is calm or troubled. In the first case, the deposit is m.ade tranquilly, and the OOLITIC ROCKS. 107 result is a compact and homogeneous rock. When, however, the water thus charged rises from a slight deptli, or at a point where it is subjected to tlie in- fluence of marine currents, the matters already de- posited are so tossed about that they present all their surfaces to the petrifying action. The in- crustation thus caused deposits itself all around them in concentric layers ; and their final combination, or massing together, causes them to resemble a heap of little eggs. The aggregation of all these oolitic par- ticles by the incrusting matter does not completely deprive the deposit so formed of its primitive cha- racter, and it is accordingly named oolite (or stone formed of eggs). The structure of this kind of rock has been called by geologists. Oolitic. The submarine deposits resulting from Geyserian action are of much less importance than those which are due to mechanical sedimentation. The physical forces play only a special part in their production. The life of the globe is the cause of numerous mo- difications in the aspect of the submarine soil, and in the nature of the deposits which accumulate at the bottom of the Ocean. Independently of the re- mains of terrestrial animals and plants which are borne into the sea, and swept through its deptlis by marine currents, or rolled by the waves, innumerable creatures live in the sea itself, and enrich it witli 108 THE BOTTOM OF THE SEA. their S])oils. A rapid stu ly of these beings is indis- pensable to whomsoever \AOiild form an accurate idea of the submerged portion of the earth's crust, and of the phenomena which are produced on that wonderfiil stage of animate and inanimate existence. 109 SUBMARINE LIFE. 1. Exuberance of Life in the Depths of the Ocean — Tableau of the Tropical Seas — Life in the Seas of the Temperate and the Frozen Zones — Natural Illumination of the Oceanic Abysses. Shall we say the play of life is pleasing to the Deity ? Everywhere we see, or we sensate, that great and incomprehensible manifestation of His omnipo- tence. Myriads of animals and plants people the earth and the air with forms of grace and beauty ; but in no part does the creative power reveal itself with more of grandeur and magnificence than in the abysses of Ocean. There, in fact, may be discovered the principles of all life. In the inspired account of the creation we are told that " in the beginning " the Spirit of God '' moved upon the face of the waters." The surface of the sea is less varied than that of the dry land ; but look deep into its bosom, and no region of the earth could give so vivid an idea of the exu- berance of life. Forms the most unexpected, a fecundity the most marvellous, challenge our admi- ration at every step we take through these wonderful regions. Here, to all appearance, is a plant, a minia- ture tree growing upon a rock ; its branches are 110 THE BOTTOM OF THE SEA. verdiireless, but, <^.traiige to say, flowers of the most brilliant colours spiing from their extremities. The petals have the po^ver of motion, and by this motion they cause a miniature current to flow unceasingly towards tliem. T^nhappy are the animalculae who may be drawn into this perpetually renewed stream, for it flows into the mouths of the zoantharia, or animal-flower to which they serve for food ! See ! — there are two eyes sparkling in the sandy bottom. A living form, w^hich escaped our observa- tion before, detaches itself, as if a leaf rose, undu- lating in the water, after having stirred up around it a cloud of sand or other earthy particles. That living form is a turbot or a sole. At the least hint of danger it will retreat to the bottom, and, disposing itself flat upon the sand or mud, become almost in- visible. This rase is the only meane of defence pos- sessed by these creatures, and almost any other fish is bold enough to make them its prey. It is worth noting that one side of tlie body is white, the other (on which the eyes are phiced) is greenish-brown, resembling the bottom of tlie sea. And that bundle of serpents in violent agitation at the entrance of an ocean-cavern ! How they twine and writhe as tliey seize upon the living prey which an evil destiny draws into their neighbourhood ! Suddenly they launch themselves precipitately out CV'PTLE-FJSll. lis of their darksome retreat; a body ot some kind, armed with a sharp beak, has clutched hold of the creature ; two enormous eyes light the march of a more hideous monster than imagination ever de- picted. But a gigantic form advances rapidly against it. A terrible struggle seems imminent. No ! the monster with the long arms vomits a black poison ; the water to a great distance around it is filled with a dense fog ; the enemy retires, and the poulpe con- tinues to hunt his prey in a domain which few ani- mals dare approach. The ungainly bulk of the various kinds of whales ; the elegant forms of the argonauta ; the crab in his coat-of-mail ; the sea-urchin, which one would with difficulty recognise for an animal if it were not for the singular movement of his spines and his locomo- tive suckers; the innumerable swarms of fish which everywhere furrow the ocean, thicker than birds and insects wing the air ; the immense shoals of medusae transported by the marine currents like clouds of locusts on the wings of the wind — all these hosts of the sea, after all, occupy but a limited region in its immense extent. As soon as we descend a little below the surface, what interesting species and elegant forms conceal themselves, so to speak, in organisms of the simplest character, because adapted to the uniform existence 114 THE BOTTOM OF THE SEA. which they all lead! What richness may be found ill that relative poverty! — what profusion of Life in those abysses to which we have not even access ! The inhabitants of the greatest depths, Jke those of the greatest heights, are the most uniformly dis- tributed. Many of them are genuine citizens of the world ; others, inhabiting the low bottoms, are sepa- rated from the rest of the world by the deep waters as by an impassable barrier. It is near the common surface, in regions swept by the winds, and subject to every variety of temperature, that animals exhibit those diversities of character which fit them either for the torrid zone, or the frozen regions which surround the poles. A current of warm water is as effective in keeping the distinct faunae apart as a rampart of flames. The Gulf Stream nourishes beings to which the neighbouring waters would prove fatal ; while, on the other hand, its own genial boundaries are impas- sable to species accustomed to the cold northern seas. That roving giant, the whale, hunts in cold waters, and we never encounter him except he is in pursuit of a shoal of herrings or other small fish, of which he devours whole nations at once. Throwing his vast bulk upon the serried ranks of his feeble enemy, he fills his maw with legions of victims, and keeps them crowded together in that antechamber of death, to devour them leisurely one by one- — his contracted CLIMATES OF THE SEA. Wt swallow setting a limit to his enormous appetite. The cachalot (spermaeeti whale) finds himself at home in warm regions, and there disputes the empire of the sea with the terrible shark. The phoca or sea-cow, the porpoise, and the narwlial leave free CO the dolphin the equatorial belt of waters, and fix their cantonments in colder regions. Often they fur- nish unhoped-for resources to the adventurous wan- derer in latitudes covered with frost and snow. There is an immense difference in the aspects respectively of warm and cold seas. The actors are not the same. The landscape itself presents totall}' different characters. Numerous plants contribute their graceful presence to adorn the hills and valleys, but (as we observe on land), they are not the sam^^ which grace the lieights with their long flexible rib- bons, swept by the currents, and which constitute the sea-green meadows in the calm deeps of the ocean. The richest vegetation is found in the temperate zones. There flourish immense forests, even more mysterious than the sacred woods of olden time. Fish, molluscs, crabs, are the happy denizens of these shady retreats. But who can flatter himself that he is familiar with these haunts ? Do they not rather seem for ever closed against the intrusion of man ? Who can presume to fathom the mystery of these immense tracts, denser with foliage than the virgin 118 THE BGPTOM OF THE SEA. forests of the New World ? And what of the joys and griefs, the struggles and massacres, of which, if the faint conceptions of our imagination can be trusted, these vast wildernesses may be the scene ? If you desire an illustration, see there, among the rank herbage and flags at the embouchure of that great river, an animal which measures anything under eighteen feet from the head to the extremity of the tail. His form recalls that of a pentagonal column or a log of w^ood. He is squatting there, silent, im- moveable. His tremendous jaws have an almost benignant expression, and all around float barbi lions, looking like little worms. What a prey for any little fish that may be swimming in the neighbourhood ! But these worms are under the guard of a great monster. The little fisli advances in haste to seize them. The benign jaws separate, and in a moment he is swallowed. Perchance he makes a silent vow that he will never again hunt this kind of prey ; but if he has been this time the sport of an illusion, has he not often given chase to worms as supple and as frisky ? The worm floats in the water, or hollows out for itself some abode in the tine sand, far from all agita- tion. It nourishes itself with the infinitely little, but sometimes it attaches itself to great animals, at whose expense it lives, as we see in the case of ter- restrial creatures. Certain species attain a consider- FKCUyiJlTY OF FlISH, liy able leni>th. Everywhere they encounter voracious enemies. Pursued into the pools, tracked in th( sands, these creatures escape annihiUition only by their extreme fecundity. It would seem as if Nature — in the greater number of beings that people the ocean — had sought to compensate them by an incredible fe- cundity for the causes of destruction by which they are surrounded. Some fish of large size have only two or three young, like the majority of terrestrial animals ; but what shall we say of the fertility of the herring, the mackerel, the cod, the sturgeon, and other inhabitants of the seas? It has been calcu- lated that if a herring could multiply during twenty years without losing any of its spawn or fry, its offspring would form a mass ten times greater than the globe. Obviously, the smaller creatures which are destined to serve as food to these enormous hosts must be more prolific still ! As we advance towards the equator, vegetation becomes less abundant and less varied. The waters are too much heated to be agreeable to the great^^. number of the algae, and if in any part of tx' equatorial seas the submarine vegetation attains the scale of grandeur, it is still wanting in the delicacy and elegance which characterise the vegetation of the temperate zones. 120 THE BOTTOM OF THE 6EA. Nor are the frozen regions of the earth more agreeable to the algae than those which are too highly heated. They disappear long before wo cease to find traces of animal life. Flowers pre- serve their brilliance under the snovv, which pro- tects them from the too intense cold ; but the polar ice does not seem to perform a similar kind office for marine plants. Life is extinguished at the poles by sheer numbness, and these plants are among the first of living things to resent that effect. Eocks^ sand, and mud are here only accidents of the submarine landscape. Here we no longer find the charming rural retreats (if the expression be allowable) of the hippocampi, those quaint hybrids of the creation : here are none of those republics of stone built up through age succeeding age by armies of insect workmen. Nature seems to have reached the end of her resources. The beings con- demned to these gloomy solitudes are not the creatures of a single element, but pass their lives alternately in the air and in the water. They are like a link between the aerial and the submarine worlds. The sea, covered with thick masses of ice, supplies them with but little nourishment in winter. During this season, therefore, they hunt such land animals as chance may throw in their w'ay.; they even prey upon one anothei-, and we know how INHABITED REGIONS OF THE OCEAN. 121 dangerous their neigbbonrhood is to the sailoi- wlio is compelled to winter in these inhosj)ittible regions. Thus, heat on tlie one hand, and cold on tlie other, arrest the extension of life beneath the ocean. It is not necessary to descend far below the sur- Fig. 23. — The Hippocampus. face of the sea to find the limits of that vital zone which seems to us at first so immensely extended. At slight depths every undulation of the surface acts as a disturbing cause, and obscures vision by rapid alternations of light and shade. Soon the 122 THE BOTTOM OF THE SEA. silence and the darkness are not more than momcii- tarily troubled by the sinking of a cable, or the I roken remains of a wrecked vessel. Before arriving at these profound depths there are regions to which the light of day but rarely and with difficulty pene- trates, and which yet are inhabited by legions of living beings. From what star unknown to us do they borrow their light ? Or does their special nature permit them to substitute for sight a sense more delicate still ? No ! these animals see clearly, and one of their functions is to find light for them- selves — they are phosphorescent. Fr-^dol observes : '* We are now aware that the infusorisB are not the only animals which cause the phosphorescence of the sea. This beautiful pheno- menon is determined also by the medusae, the asterias, the molluscs, the nereids, and by some crustaceans and fishes. These animals engender light as the gymnotus engenders electricity. They even multiply and develope the eifects of the pheno- menon. The light which they produce rapidly changes from a greenish to a reddish tinge. At certain moments, the darkness is lighted as by ladiant points running into starry feathers or fringes v)f light. So vast is the number of these phos- phorescent animals, that they appear at a distance like metallic masses heated to whiteness, or like SUBMAltlME ILLUMINATION. 12:? bouquets of fire formed of myriads of gliltciing points; or, again, tli(^y may be compared to festoons of coloured lamps such as are used in public illumi- naiioDS — or, yet again, to burning meteors, elongated or globular. Mingling and grouping, approaching and separating, ascending and descending, these wondeiful wreaths of light describe a thousand capricious curves ; and if they fade away or seem to be extin- guishe i, it is only to be rekindled the next moment, and to pursue again the same fantastic course. " It is in the waters of the warmer latitudes that the starfishes display all their brilliance. The finest illumination on the occasion of a public fe^e can scarcely give an idea of this submarine spectacle. Has the reader seen on a fine summer evening the flashing splendour of the myriads of fireflies which sport away their brief existence in the valleys of Italy or of Corsica, and which for their immense numbers may be justly compared to the sparks issuing from a conflagration ? Has he remarked in the blossoming herbage hu^v the pretty little glowworm spreads around it a brilliant red or green light ? Imagine, then, glowworms and fireflies mingled together in all forms and colours, and in such immense numbers as to extend over many hundre Is of square leagues ; add to this that every nook of the vast region wliich they ilkinimate has its own proper light — that what 124 THE BOTTOM OF THE SEA. seems to us brown, lustreless, and uniformly dull when we observe it by tbe light of day, acquires in the abysses of the Ocean those rich tints and phospho- rescent gleams with which the Arab story-tellers liave glorified their dreams of fairyland — and you will have a faint idea of the wonderful spectacle presented by the Ocean to the diver who dares to brave the innumerable dangers of a submarine ex- cursion ! 2. Migration of Marine Animals — Nests at the Bottom of the Sea^- Fisheries. In all ages man has derived instruction from the observation of nature. The sea above all has sharp- ened his intelligence, and therefore we are not sur- prised to be told that the nautilus or argonaut, one of the oldest-known of marine animals, has the credit of having taught him navigation. The species which inhabits the Mediterranean {Argonauta Argo) must in former days have been more widely diffused than at present. It is now found only in the better sheltered latitudes — the Archipelago, the Adriatic, and the Straits of Messina. On a beautifully fine day, when the air is serene and the sea tranquil, the elegant shell of the argonaut may be seen floating on the water, which it navigates by means of a locomotive tube, and by spreading to the wind tw^o Tnl:: ARGON AUTA. 120 of its limbs furnished with fine silver-coloured membranes — the other limbs being extended, like oars, on either side of the shell. Gazing on this elegant and living vessel, its delicate shining mem- branes looking like little wings, it is easy to under- stand how Aristotle and Pliny saw in the nautilus one of the marvels of the sea, and pictured it as a representative in miniature of the art of navigation. The argonaut is found in many seas, but is not, properly speaking, a traveller. The least billow, the approach of the slio-htest peril, causes the timid creature to draw in his arms, upon which, in con- sequence of refilling his shell with water, he sinks into the calm and safe depths of the sea. His re_ treat is so cleverly managed that it is extremely difficult to take him captive. The officers of the Vaillant, desiring to obtain some of these beautiful objects, sent a boat's crew, during a voyage to the Cape of Good Hope, to capture one or more speci- m'^ns ; but scarcely had the men moved their hands towards them, than the too clairvoyant animals sud- denly filled their shells, and, sinking to the bottom, left the sailors gazing at each other in disappointed admiration. Attention has always been attracted by the forms of fishes, and from them, in fact, we appear to have borrowed the idea for the forms of ships. The 126 THE BOTTOM OF THE SEA. incredible agility of the dolphin, which travels in a company so numeroas, and gambols so joyously in the track of the sailor, together with the sudden appearance and disappearance of immense shoals of fish at certain seasons, and the analogous migra- tion of birds, naturally suggested that fish make long journeys, and that certain species accomplish these journeys periodically. The curious circumstances of these periodic expeditions did not, however, become known until the surface of the Ocean had been sub- dued by the nations of the West ; until the fisheries of Newfoundland, of the coasts of Norway, of England, and of Brittany had called the attention of the learned to the facts, a few instances of which were alone known to the ancients. The tunny is among the number of fish that were known to be travellers before the modern epoch. It is found in the Mediterranean moving in a triangular phalanx; one point forming the advance, as if to cleave the waves more easily, while the base is often of gxeat extent. It is also abundant in the G-erman Ocean, on the coast of Guinea, in the region of the Antilles, in the waters of Brazil, and in those of Chili and China. The warmer w,aters are resorted to by the tunny for 1 reeding. Immense numbers pass the winter in the eastern part of the Mediter- ranean, where they deposit their eggs at depths o ' THE TUNNY AND HERRING. 127 about a hundred feet more or less, avoiding with great care the shoal-water. Troops of tliem leave the east in the month of May, and are then to be found in abundance on tlie coasts of Sicily and of Southern Italy. In tlie autumn they return to the Tyrrhenian Sea. Pliny relates that the fleet of Alexander encoun- tered such immense numbers of tunny-fish that they could not make their way through the living mass, nor could any noise or commotion they could raise avail to disperse them. They were compelled at last to range themselves in order of battle, as if to break through an enemy's line. The dolphin, the salmon, and the sturgeon also travel in companies of their own species, but not in great numbers. They even mount the larger rivers, and forget, for a time, the salt-waters in which they had so many enemies to encounter. But of all fish-travellers, for the distance traversed and other points of interest, commend us to the inliabit- ants of the colder parts of the temperate zone. The herring occupies the first rank in those classes of animals of which man has sufficient knowledge to convert them to his profit. It abounds in the northern seas, and it has even been thought that immense shoals of herrings live during a great part of the year under the polar ice, where they are safe from the 128 THE BOTTOM OF THE SEA. attacks of their numerous enemies.* However that may be, some naturalists think — and, as it appears to us, with good reason — that during the spawning season the herring simply quits the level bottom of the Ocean to deposit its eggs in the waters which afford the protection of rocks or of abrupt eminences against the force of the marine currents. Herrings do not obey simply the rule of caprice in making their migrations. They appear to select the coasts towards wijich they are travelling. As all the paths of the sea may not be convenient for the passage of a great host, though small detach- ments may make their way without difficulty, the armies of herrings do not follow indifferently any route. They traverse the regions where the staple of their nourishment most abounds. Having visited a coast they will return there freely the following year. But suddenly, without any apparent reason, they may disappear for a time, or perhaps for ever. The arrival of the mackerel is sometimes the cause of their departure. Being of larger size than the herring, as well as better armed, the latter flies as at sight of an enemy too formidable to be encountered. * The best authorities no longer countenance this theory. The following paragraphs, in which the fact of the migration of herrings is implied, are also open to dispute. The reader is referred to the gpecial works of Bertram and Mitchell. — Tr. Fig. 24. — Herrings attacked by Tunny-fish. MIGRATION OF II hli RINGS 131 Nearly all lishes are to be more or les- dreaded by herrings. They lly like troops incessantly harassed by guerilla bands excited to the pursuit. The cod, the tunny, and the shark emulate each other in the dc'StiiK-tion of these swarming multitudes, whose propagation would be too rapid if they did not serve as nutriment to the other inhabitants of the seas. During many ages the coasts of Norway were the favourite resort of herrings. Thousands of vessels were devoted to the fishery. About the year 1600 they migrated towards the German coast, and their fishery enriched the Hanseatic cities. It is about a hundred years since immense shoals of them visited St. George's Channel. We are equally ignorant of the cause of their arrival and that of their depar- ture. At the present time, mackerel are very abundant on the coast of Norway. May this fact account for the abrupt departure of the herrings? Or is it that the herrings have not found, as in St. George's Channel, a sufficiency of nourishment? However this may be, the celebrated Franklin put to a profitable application the memory of the herring, rind its love for its native place. Of two neighbour- ing rivers, the one Avas visited by a great number of these fish, whilst none appeared in the other. Frank- lin caused the nets covered with spawn to be taken iVom the one and placed in the other. The herrings 132 THE BOTTOM OF THE SEA. did not fail, in the following year, to make their pil- grimage to the river which had given them birth, and afterwards both rivers were equally well fre- quented. The following facts will give an idea of the im- mense armies of herrings which invade our seas. The single city of Glasgow^, in Scotland, exports annually more than twenty thousand pounds' worth in value. In 1773 the fishery in a single firth upon the Scottish coast employed every night one thousand six hundred and fifty boats, and the weight of the fish they cap- tured was twenty thousand tons. On one occasion, upon the western coast of the Isle of Skye, their number was so great that it was impossible to dispose of them in the usual way. Alter all the smacks had been filled, and the v\hole neighbourhood was suffi- ciently provided, the farmers used the remainder for manure. For a long time the shoal continued to visit the same coast, and appeared in the Sound of Sleat in such immense numbers, that they quite filled Loch Hourn from one extremity to the other, though it is more than half a league in depth. The tide left so many behind it, that the shore was covered to a depth which varied from three or four inches to eighteen inches, and at low-water they were visible as far as the eye could reach. Herring-shoals are not only very thick, but the fish COD-BANKS OF NEWFOUNDLAND. 183 are closely packed in them, and in their advance they sometimes drive all other fish before tliem. The shoal of which we have just spoken had thus driven before it flounders, skates, and other large fish, which perished on the shore among the first ranks of the herrings. The mere pressure of the mass forces those in tlie front ranks to advance, whatever obstacle presents itself. This fact is utilised in tlie fishery. Very long nets, to one side of which are fixed plummets of lead, and to the other buoys, are let down vertically into the sea. The meshes are large enough to admit the head of the fish, but not to let the entire body pass through. If the herring were to try to withdraw, the openings of his gills would catch in the net and make escape impossible. The net is generally let down at night, because the her- rings are then more abundant. The cod, that other nomad of the sea, is found in armies at the meeting of the cold and warm waters upon the Bank of Newfoundland. An immense quantity of small worms are found in that locality, of which the cod makes his favourite food. Year by year these barbarian hordes renew their invasion — every year they are arrested in their course by the Gulf Stream ; and after being decimated by the fishers, their great enemies, the broken remainder of the band retire into the polar seas to recruit their 134 THE BOTTOM OF THE SEA. strength. The fecundity of the cod is incredibly great. The celebrated microscopist, Leuwenhoeck, counted in a single individual as many as nine millions of eggs. Their multiplication being so rapid, it is easy to repair in a single season the losses of an army. Sharks and other great fishes destroy the cod b ^' thousands ; man — a more terrible enemy still, per- liaps — makes a shambles of his feeding-ground. What a blessing it was to these creatures when our race was confined to the limits of the ancient world! What a happy tranquillity did they not enjoy, before the illustrious Cabots dared to face the fogs and frozen waters of Newfoundland and Canada! The cod-fishery is by far more dangerous and more tedious than that of the herring. The net cannot be employed with the same facility, although it is still used upon the coasts of Norway. A line is generally substituted for it. To the line is fixed a hook, with a bait which the cod is not slow to seize hold of His weight renders the operation of pulling in most laborious. To form an idea of the amount of work done by a fisherman in a single day, it is enough to state that a strong man may capture as many as four hundred of these fish, weighing, on the average, from fifteen to twenty pounds each ; some individuals, how- ever, measuring nearly five feet in circumference, and THI': MACKEREL \Zb from six to seven feet in length, and weighing as much as eighty pounds. Each vessel employed in the fisherv sends, on an average, thirty thousand cod to Europe, cind we know how hirge is the number ol' vessels en- gaged in the trade. Many other fish furrow the vast extent of ocean on every hand, swim in innumerable legions along the coast, or hide themselves in the deeps, where the calm promises them greater security. The mackerel is of all the most cosmopolitan. This popular favourite visits every year the coasts of Norway ; it abounds in the markets of Germany and of England during the summer (the season at which it swarms in the North Sea and the Baltic) ; it is found in equal plenty on the coasts of Iceland, of Ireland, and of Spain in the Mediterranean. It is fished by the inhabitants of the Canary Isles, in the neighbourhood of nearly all the American islands, and even at Japan and Suri- nam. It disappears every year at a certain time, retiring far from the surface to return again in the spring. The mackerel, we may observe, in conclu- sion, is a great feeder ; it is so voracious that it will not hesitate to attack animals larger than itself; the shoals of small fish which keep in general near the coast are, however, its great resource. Small fish which travel in shoals or immense herds are next to defenceless. If the centre of the mass is 136 THE BOTTOM OF THE SEA. comparatively safe from the greater number of their enemies, the sides are exposed ; and the accumu- lation of such immense masses of living beings must of course attract the attention of rays, sharks, and other tigers of the sea. Some species of small size, such as the anchovy and sardine, are great travellers. They dwell in the Atlantic Ocean and the Mediter- ranean Sea. The anchovy also is found in the seas of Asia and America. It passes from the Atlantic into the Mediterranean during the months of May, June, and July, and directs its course towards the Archipelago and the Syrian coast. The most consider- able fishery is in the Tuscan waters, where large numbers are captured from April to the end of July. The ancliovy is taken during the night, when there is no moon, by means of a boat called by the fishermen a fastier, upon the deck of which a fire is made. Another boat carries a net called a rissole, which is more than two hundred feet long by about thirty feet in breadth. When the fastier is sur- rounded by a sufficient number of anchovies, the sailor in charge gives a signal to his companions, who throw the net into the sea, and extend it in such a manner as to surround the fish that have been attracted by the light. Suddenly the fire on the fastier is extinguished, the terrified anchovies fly in all directions, and are of course captured in the meshes HAUNTS OF FISH. 137 of the net. This method of fishing is practised at a distance of one or two leagues from tlie coast. At tlie l-eriod of spawning a different plan is adopted. The fish then approach the shore to deposit their eggs upon the shallow sands, and are caught in great seines or dravvnets in the ordinary way. The sardine fishery is managed like that of the anchovies, only the meshes of the net are a little more open. The sardine is found in its highest per- fection on the coasts of Brittany. Herrings, mackerel, and col prefer to deposit their spawn in rocky localities ; anchovies love better the shallow sandy bottoms. Thus the character of the sea-bottom influences the inhabitants of the deep in their peregrinations. Some examples of this fact are generally known. The following is one of the most remarkable. The Spaniards for a long time enjoyed the mo- nopoly of the tunny trade : seven immense es- tablishments of this fishery existed on the shores neighbouring the Straits of Gibraltar ; and there passed annually through the Pillars of Hercules more than four hundred thousand of this fish. This source of wealth was lost in a single day, owing to the earthquake which overthrew Lisbon. The Span- ish coasts were rocky, and furnished an agreeable resort to the oceanic travellers. On the day of the 138 THE BOTTOM OF THE SEA. earthquake great quantities of sand and pebbles were torn from tne coasts of Africa, and thrown upon those of Europe. The latter were thus converted into shallows and sandbanks. The tunny-fish, having to extend their journeys to the coasts of Tetuan and Sale, acquired more liberty. It required nets extravagantly long to capture them, and, in fine, the fishery was transferred to the Sardinian and Italian coasts. It would be very difficult to account for the pre- ference shown by the tunny for a rocky coast. It is possible, however, that the facilities it affords For shelter is the chief reason. Great and imposing as the tunny looks, he is so timid that he makes scarcely an effort to escape from the net after a first attempt has failed, and thus gives very little trouble to the fishermen. The nets used for the tunny fishery in the Medi- terranean are like enormous sacks, which in Italy are called tonndrk It is at the commencement of April that the fishermen begin to construct the fortress into which they expect the tunny to enter ; immense nets are fixed to the bottom, by means of anchors, and weights so heavy that the most violent tempest will not dislodge them. The tunny loves, as we have said, the rocky coasts, or passages between the isles. It is in such places that the fishers establish their THE TUNNY FISHERY. 139 tonnare\ the passage throughout is carefully closed by nets, between which only a small opening is left, which we may call the exterior gate of the submarine fortalice. That gate which leads into the first apartment, called the Tialle, is made on the side of the channel by which the tunny arrives every year. When a troop of these animals has entered into the halle, the fishers close the exterior gate of the ton- ndra ; they then terrify the tunnies by throwing gravel at them, or by scarecrows made of sheep- skin — or they even pursue them until they are induced to pass through a second gate, into the "ante- chamber ;" this second gate being then closed, the first is opened again to admit a fresh party into the halle. When a sufficiently large number of these animals are assembled in the antechamber, similar tricks are resorted to to drive them into the chamber of death, where the fishermen kill them with lances. Sometimes despair renders them furious ; they fling themselves out of tlie water, and break their necks or bruise their heads against the rocks and boats. We have reason to be astonished at the facility with which tlie tunny is fished, when we recall to mind its great size. It is generally from two to three or more feet long, but occasionally is consider- ably bigger. It is often found of the size of a man, and has been taken from six-feet-six to eight feet 1^'^ THE BOTTOM OF THE SEA. long, upon the coast of Brazil. Some naturalists relate instances in which tunnies still longer have been captured, and which were otherwise remarkable for their unusual dimensions. In many other cases, and sometimes to capture a prey less precious, man is himself forced to descend to the bottom of the sea. It is thus that he fishes the sponge, the pearl, the trepang, and the coral. We will devote a special chapter to these, adventurous and barbarous expeditions. At present we continue our observations from the shores, or, at least, we will just now explore such parts only of the bottom as we can sound by means of a boat. Here is a quantity of spawn floating on the sur- face. This spawn is composed of a number of eggs, united by a transparent jelly. It serves as pasture to fish of every kind ; but that which is not devoured will become little fish, and be called to higher desti- nies, if the sticklebacks, greediest of all the small fry, do not destroy it, or if the swell of the sea does not throw it upon the coast, where it will corrupt and spread around a phosphorescent glow. At the bottom, the cod, the herring, the mackerel, the tunny, and other fish have deposited their spawn in the crannies of the rocks, under the stones, in all places well defended against the agitation of the waters. Notwithstanding these precautions, how NESTS OF P^ISII. 141 many generations of thera are not devom-ed b^lore they are hatched, by hungry rovers, and often by the fish themselves, who had secreted their offspring with such care ! Life is preserved in the sea by the in- credible fecundity of marine animals, a fecundity of which we have now seen a lew examples. Some inhabitants of the seas, however, appear to take the most jealous precautions to protect their de- scendants from the attacks of a too implacable enemy. Some, like the marine worm, the solen, hide them- selves entirely in the sand ; others content themselves with secreting their eggs ; others, again, actually con- struct nests in the algae, the leaves of which they interlace for the purpose. The stickleback, in particular, so much to be dreaded for the fry of other fish, takes the greatest care of its own eggs. Living usually in the sub- marine forests, it is of the most savage character. In the spawning season, it weaves its nest most ar- tistically, and there deposits its eggs. Unhappy is the fish which approaches that sanctuary : whatever be its size, it will have to defend itself from the furious attack of the stickleback — it will have to bear stroke redoubled upon stroke ol" its prickles. Its bites will sometimes rend the skin. M. Arderon relates that he once preserved a stickleback in a great jar of water, where it devoured in five hours 142 THE BOTTOM OF TEE iSEA. fourteen small fry about an inch long, and it seemed to be very comfortable after its sumptuous repast. It would not suffer any other fish in the same vessel, and attacked any that might be put in, even though they were ten times its own size. One day M. Arderon put a small fish in ; the stickleback imme- diately gave it chase, bit a morsel out of its tail, and if it had not been taken from the vessel, it would most certainly have killed it. 3. Terrible Conflicts of Marine Monsters — Massacre of the Weak by the Strong. Life is sustained by death ; we are constant wit- nesses to the truth of this adage. It would seem as if a given quantity of life had been conferred on the globe, and that it neither augments nor diminishes, but that it is incessantly transformed and renewed — in a word, that all death reproduces an equivalent quantity of life.* Although it is true that man has sustained the most deadly struggles against monsters since the earliest ages, the memory of which is perpetuated in legends and fables, he has in later times extended * Quantity cannot be piedicated of life. M. Soniel occasionally philosophises in this vein, and we have generally allowed liira to have his own way. If the reader cares for another opinion, ours id that this is not the language a pliilosopher ought to use, — Tb. UTTLTSATION OF FISH, 143 very considerably the circle of liis adventurous ex- peditions. As the marvellous has given place to more exact ideas concerning the theatre ot his ex- ploits and the nature of his enemies he has felt his audacity increase day by day. He has driven his keels til rough every inch of the sea's surface, and he has sought to bring the powers of the Ocean under the same subjection as those of the earth. He has offered deadly combat to the whale, and pursued him even into the solitudes of the frozen regions, where some species have taken refuge to escape his blows. He derives from nearly all its species a great profit by melting down their grease and their liver to extract an oil. The thick skin of the greater num- ber of whales is converted to numerous uses ; the fins of the balsena, the spermaceti lodged in the head of the cachalot, the amber^^ris which forms in the in- testines of that animal when he is ill, are among the articles of commerce furnished by the whale species. It is to the pursuit of these treasures that we are indebted, in a great degree, for our exact knowledge of the habits of these marine monsters. Between some of them there prevails a sufficiently good un- derstanding, but others appear to live in continual warfare ; each being ready, at an instant's notice, to precipitate itself upon the other when they meet. Such appears to be th^ caso with the balapua, O'' 1*4 TUIiJ BOTTOM OF THE SEA. whalebone whale, and the swordfish, though some say the latter is always the aggressor. Sailors report that the balaena, whose vast mass imposes on nearly all the inhabitants of the seas, and who, under his thick cuirass of blubber, may brave with impunity their attacks, seems to be troubled in an extra- ordinary manner when he perceives the swordfish at a distance. According to the same statements, the swordfish makes a rush at the whale, which dives to the bottom to avoid him. His enemy, keeping close in pursuit, compels him to remount to the surface. The whale has no other means of defence but his tail ; with a single blow he might annihilate his enemy, if he could only get at him, but the swords- man is quite as alert as his antagonist is strong, and easily eludes his efforts ; he springs into the air and comes down upon the whale, not to pierce him with liis sword, but to give him still more dangerous wounds with the serrated edge of that terrible arm. M. de Tessan witnessed an interesting combat of this kind jn mid-ocean : the entry in his diary is as follows : — " Lat. 23° W N., Long. 108° 49' W. ; 16th Dec, 1837. — I have had a good view, although at a considerable distance, of a fight between a whale and a swordfish. The latter leaped into the air, to the height of ten or twelve feet, made a half-turn, and ^ctme down in the water upon the head of ttie whale. WUALES. 147 His blows were repeated again and again ; and the whale, at each fresh attack, struck the water violently with his tail, and often appeared above the surface to blow. The combat lasted a long time, and was always confined to the same spot — which proves that the whale dill not attempt to fly from his enemy. Snrl- denly, after a moment of repose, tlie whale itself sprang from the water, to a height of about three yards, and, coming down with a crash, caused the water to spring up with great force. After this tremendous effort the struggle ap[3eared to cease, at least I saw nothing more of it." The balaena, or whalebone whale, is the least voracious of the cetacea. He is much less so than the cachalot or spermaceti, which, although of less bulk, may nevertheless be reckoned among the giants of creation. The spermaceti has a large throat, and is able to swallow at a mouthful a lar^e quantity of fish. Soiue curious statements are made, to this effect, to which it is difficult to yield implicit faith, although they are vouched for by naturalists. '• A spermaceti whale, having beeen wounded,' says Grantz, "vomited a shark sixteen feet long; and there were found in his stomach the bones of a fish more than six feet long. Probably," adds the same author, "the fish that swallowed Jonah was of this sjDecies." 143 THE BOTTOM OF THE iStA. What a monster this must have been, which could relieve the ocean, at a single mouthful, of one of its most dreaded inhabitants ! The voracity and power of the shark itself are terrible almost beyond credence. It is formidable even to the great cetacea; it will follow, ^^ithout intermission, vessels sailing in the torrid zone, and devour whatever they let fall into the sea. Should any portion of the equipment or baggage fall over- board, it instantly becomes the prey of this monster. Its jaws, furnished with a hundred and thirty strong and pointed teeth, are powerful enough to chop a man in two at one bloAv. The only check imposed on its voracity by nature is due to the position of its mouth. Instead of being at the extremity of its body, it is placed on the lower surface, at some distance from the snout, so that to seize its prey the shark is obliged to incline itself on one side. While it is making this movement its intended victim often escapes. When it has once tasted human flesh, the shark is certain to continue its visits to the places where he expects to find it. For this reason the pearl-fisherie); are the theatre of dreadful struggles, in which the coolness and intelligence of man happily triumph sometimes over this tiger of the seas. Every diver, when he descends, is armed with a sharp knife. SHAEKS. 149 When a shark attempts to charge upon liiin, the object of the diver is to stab him with liis knife in the belly. The negroes of America do not fear to measure their strength and skill against him. The instant they perceive their enemy they dive to a great Fig. 26. — Fight between a Sailor and a Shark. depth; then, rising as suddenly, they stab the shirk in the belly before he has time to take up his offensive position. But it is not necessary to seek in the annals of negroes or Asiatics for acts of courage and of hand-to- 160 THE BOTTOM OF THE SEA. baud struggles (if one may use the expression) be- tween heroic men and their terrible adversary. An English merchant-vessel having arrived at Bar- badoes, many of the sailors threw themselves into the sea to take a bath. An enormous shark advanced towards them ; every one endeavoured to reach the ship's boat sent to their aid. At the instant when he was about to escape from the water, one of these poor fellows was bitten in two by the monster. The friend of this unfortunate man was lashed into fury, and, seeing that the shark was looking about in the bloody water for the remains of his victim, the brave young fellow sprang into the sea, resolved to perish as his friend had done, or make the monster pay for his audacity with his life. In a moment the shark made a dash at the intrepid sailor, and now he was close upon him. Already he had turned himself over on his side, and opened his immense jaws. With his left hand the sailor gripped hold of the shark under his pectoral fin, and with his right hand, in which he held a sharp poniard, he struck him blow redoubled upon blow. It was in vain the shark endeavoured to disembarrass himself of his enemy ; the sea was dyed with his blood, and yet the sailor's arm never seemed to tire of repeating the blows. The men in the boats belonging to the various ships moored in the load awaited with anguish the end of VOltAClTY OF FJSTJ. 153 the terrible conflict. At length tliey could breatlie ireely. Human heroism and skill had triumphed; the man was seen pushing the carcase of the monster towards the shore, where he tore out his entrails, and took from them the mangled remains of his friend. Nearly all tlie other inhabitants of the sea are voracious ; but their small dimensions, and tlieir feebleness relative to their means of attack, render them less terrible to man, and mask their massacres and depredations of all kinds. It needs the eye of the naturalist and the sailor to observe those lesser details of oceanic life which do not affect us directly, nor strike our imaginations like the more frightful ravages of the great marine monsters. The turbot and the sole, those deformed outcasts of society, as some might think, are nevertheless your true cosmopolites. They are equally at home in sandy and rocky places, but their flesh acquires a preferable taste in tlie latter. They are fished upon the coasts of Europe, at the Cape of Good Hope, in the Indian Ocean, and even in the Chinese seas. Everywhere they are the prey of numerous enemies, yet let us not be too prodigal of our pity for them. What they need is strength alone, not voracity. The bait used in their fishery are morsels of herrings, little lampreys, worms, limpets, and mussels. They will only eat, however, either livino: or fresh Iv-ki lied 154 THE BOTTOM OF THE SEA. flesh ; tliey will not bite at a morsel of herring that has been more than twelve hours dead. Look at this specimen of the delicate inoffensive gourmet ! How, with a body so thin and supple, with a mouth devoid of teeth, or any hard substance which might supply their place, conld he dream of becoming an assailant ? Nevertheless, that animated leaf swallows the shells along with their inhabitants ! At every step iii the sea we have to note the de- struction of the I'eeble by the strong, the little by the great. Let us not forget that life alone is capable of sustaining life ; it is in general the stronger that is charged with the duty of avenging the fate of the feebler. The tunny ruthlessly destroys the herring, but the pleasures of the chase are embittered by his inevitable encounter with the shark ; and often when he is in the very midst of a delicious meal of herring, lie is himself victimised by the tyrant of the seas. The entire life of marine animals seems to be passed in a study or a struggle how one shall eat the other. The problem has to be settled by continual ruses, attacks and precipitous flights, battles and deaths, without a spectator to compassionate the sorrows of the vanquished. There is no outcry, no useless talk over these tragedies. One meets another, attacks him, devours him — that is all ! This ferocious cruelty, this coldblooded and PUGNACITY OF CRAJIS. 155 implacable ferocity, we do not find in the crab. It seems that this gallant chevalier, covered with a thick cuirass, has his fits of anger^ his joys after a triumph, and is very sensible to the dishonour of defeat. The most deadly combats will take place between crabs With their great claws they seize on the hind-legs of their adversaries, and the latter find it no easy matter to withdraw their limbs safe and sound. Where is the brigand that would take pleasure in tearing his adversary limb from limb ? Instances of such cruelty have occurred, but they are happily rare. Procrustes does not often find imitators. That which disgusts us is the nonchalance with which crabs indulge themselves in this luxury, often carrying ofi* with them, as a trophy, a foot or a leg of their enemy. They are so irascible, that, if we were to put one of his own legs between a crab' s claws, he would attack it without perceiving that he was him- self the aggressor, and would continue to pinch and tear himself for a long time after he discovered the fact. It is not always against his own species that the crab directs his attacks. With his great pincers and his armour-like shell, which render him almost in vulnerable, he is the doughty enemy of all the small marine animals. But, as with the knights of old, that very armour is "ometimes the cause of danger to him. The growth 15G THE BOTTOM OF THE SEA. of the shell by no means keeps pace with the growth of the crab. There are times when you will see him painfully squeezed up in an unyielding garment too small for his body. Day after day the bondage grows more intolerable ; the creature's limbs are para- lysed, his whole life is an agony ; at length the crisis arrives, and, with an extraordinary effort, he suddenly breaks out of his prison and gains his liberty. Many die in making this painful effort ; old crabs have had the benefit of the experience two or three times re- peated. In the case of the domestic crab, which inha- bits the craggy coasts of Europe and the West Indies, the change takes place between Christmas and Easter. Until the new shell acquires its destined hardness, the sole covering of the liberated crab is a skin-like soddened parchment ; in this unprotected condition it retires into the clefts of the rocks, or buries itself under the sand, where it remains in a state of absolute immobility. But all these ruses are of little avail ; its enemies pursue it with an avidity all the greater that the crab is known to be less capable of resistance, and it is with difficulty that it escapes their vengeance. The lobster changes its shell like the crab. Some days before the period of renewal the animal seems stupefied ; he settles down in a state of torpidity, and the first sign of returniug activity is when he throws CllAHACTER OF THE LOBS'lKli. 137 himself upon his back, and battles with his pincers one against the other. Then a shudder runs through his hmbs and his whole body ; tliey throb and dilate, the joints of the armour open along the belly, those of the claws come apart — tlie moment of the creature's deliverance is at hand. But when thus freed from his sliell. the lobster is so feeble that he remains altogether without motion, and in this state becomes the easy prey of cod and other ravenous fishes. His own species, however, are in general his most dan- gerous neighbours. They have the meanness to devour the smallest and feeblest of their kind, even preferring them to the little worms hidden in the sand, or to the spawii of fish. The greater part of a lobster's life is passed in a retreat which he selects between two rocks. This lurking-place is scarcely larger than the animal himself, and from thence he springs with agility upon his prey. The instant any danger menaces him he flies rapidly towards his den, springing from the ground tail-foremost, and sometimes clearing more than thirty feet at a single bound. This armour-plated brigand, so ready to pounce on his defenceless prey, is so far from being a hero, that certain species, wdiose coat-of-mail is partly de- fective, are glad to take refuge in the deserted shell of a brother crustacean. This is the case with the 158 THE BOTTOM OF THE SEA. hermit or soldier-erab. His armour, defensive and offensive, consists of two great claws, as large as a man's thumb, and so powerful that they are capable of making very deep wounds. This ugly fellow may often be seen on the rolled pebbles of a beach, drag- ging his old house behind him. Presently he stops before an empty crabshell, he examines it under all its aspects, and, after withdrawing his tail from his old abode, he tries to enter backwards, as his wont, into the new house. Probably he does not find it to his taste, in which case he tucks himself into his former habitation, and marches off again in search of a more convenient apartment. He looks at one shell after another, until he finds an abode to his liking ; he then huddles himself into it, though it may be sufficiently capacious to contain not only his body but his great claws. It occasionally happens that two of these animals select the same shell for their lodging. When this happens, they fight with their claws till the weaker is obliged to give way. The victor then takes possession of his conquest, and for some time marches boastfully up and down before his discom- fited rival. Among the smallest of these crustaceans, there is one (the Bernhardus, or hermit-crab) which has a penchant for the shells of the small molluscs. It is only partly armed, having a helmet and a breast- THE TORPEDO AND GYMNOTlhS. 159 plato, while tlie rest of its body is covered witli a solt skin. The hermit does not trouble itself to look ibi- an empty shell, or to drive the owner of a shell out of his home; he wisely eats him. The CoquiJIauni- valva — helix-shaped, liked our garden snail — is easy to transport. Having devoured the inhabitant, and comfortably ensconced himself in one of tliese shells, some imprudent neighbour of the supposed molla>c approaches to make a meal of him, — tlie crab's liead pops out, and the would-be eater is eaten. Let us return to the high seas. There we find the ray, a flat fish, witli two different coloured sur- faces. The skin of some species is so rough that it is employed, like that of the sea-cow, to polish ivory and various woods. A powerful jaw, in some in- stances a tail set with s])ines, are for the ray for- midable weapons. In fact, all these monsters are apparently furnished with means of defence, and breathe defiance to their victims even from a dis- tance. Sometimes their striking colours, or the phosphorescent aureole which surrounds them, awakes the attention of the feeble, and gives them time to prepare for the attack. In the torpedo and the gymnotus there is nothing outward to suggest how terribly they are armed. The one formed like the raiadsB, the other like an eel or snake, they carry weapons more to be dreaded than 160 THE BOTTOM OF THE SEA. those of any animals of their species. Any fish that approaches them is killed, as with a stroke of light- ning, and devoured without a struggle. Touch them, and a shock is given like that of an electric charge ; yet certain authors assure us that the negroes handle the torpedo without danger. The electrical power of the gymnotus was unknown in Europe until 1671, wlien the astronomer Bicher, who was sent on a mission to Cayenne by the French Academy of Sciences, observed and made known the remarkable power of this fish. " I was much as- tonished," says Richer, " to see a fish resembling an eel, some three or four feet in length, deprive of all motion for a quarter of an hour the arm and shoulder of one who touched it with his finger or with a stick. I was not only an eyewitness of this effect, but 1 have myselt' felt it on touching one of these fishes, still living, though wounded by the hook with which the Indians had drawn it from the water." The savans of Paris were at that time a sceptical people. Eicher's account made so little impression on them, that for seventy years no naturalist troubled himself to inquire into it. This indifference lasted to the time of Condamine, who spoke, in his " Voyages en Ameriqtie," of a fish which produced the effects described by Richer. The phenomenon now excited attention. Dr. Ingram published some views about ANIMATED FORESTS. 101 it in 1750, and attributed the effects to electricity. The Dutch physician and philosopher, Gravesend(.\ recognised the galvanic nature of tlie shocks given by this animal. " The effect produced by this fish," he wrote in 1755, " is the same as that caused by the Leyden jar, only with this difference, that no spark is observed, however strong the shock raay be; for if the fish is a large one, those who touch it are struck down, and feel the shock through their whole body." The gymnotus does not seem to make any use of his weapon except in self-defence. He feeds ou small fishes and worms, of which great numbers aie found in the waters of South America and the Indian seas. The torpedo is more cosmopolitan ; it is no- toriously frequent in the seas of Europe. These two monsters, depositories of thunder, appear to share between them the universe of waters. Like the ray, the turbot, and the sole, the torpedo prefers for his portion the sandy flats and shallows ; the gymnotus hides among the rocks, in clear waters, and in the neighbourhood of rivers, which he often ascends. 4. Animated Forests — Animal Stones. The bottom of the sea is an enchanted country ; the animals, its inhabitants, are self-luminous; they 162 THE BOTTOM OF TEE SEA. thunder upon their enemies from a distance; tliey harden themselves into stone. We read that Daphne was transformed into a laurel. The narrators of this fable have not depicted for us the sufferings of that unfortunate maiden, her languor, the growing numbness of her limbs, her feet dried up and spreading into long roots, her arms shaping into branches covered with a polished bark. But this dream is realised in the Ocean every moment. There is no region with a favourable climate and an agreeable site, where animals are not found living in colonies, and working, by their petri- faction, at the construction of rocks and reefs of an immense extent. Heat favours their development. No part of the world presents them in the same marvellous variety as the Great Ocean and the Indian seas : " If we direct our gaze into the liquid crystal of the Indian Ocean, we shall there see realised the most wonderful dreams and fairy-tales of our childhood. Fantastic bushes bearing living flowers, the massive structure of the meandrina and astrea contrasting with the branchy tufts of the explanaria, which blossom in the form of cups, with the madriporidse, of elegant structure and ever-varying ramifications. Everywhere throughout this region the eye is charmed with the brilliancy of colour : delicate shades of sea-green alternating with COLOUR OF MARINE VEGETATIOX. 163 browns and yellows, rich purple tints passing from the most vivid red to the deepest blue ; nuUipores, yellow or pink, delicately touched as the peach, covering decaying plants with a fresh development of life, and themselves enveloped with a black tissue of retipores resembling the most delicate carvings in ivory. Near by wave the yellow and lilac fans of the gorgona, worked liked jewelry in filigree. Strewn over the sandy bottom are thousands of sea-stars and sea-urchins of the most curious forms and varied colours. The flustra, the eschara attached to branches of coral-like mosses and lichens, and the patellidse striped with yellow and purple, look like great cochineal insects on the ground. Then the sea-anemones, looking like immense cactus-flowers, brilliant with the most glaring colours, adorn the clefts of the rocks with their waving crowns, or spread out their blooms, till the sea-bottom resembles a border of many-coloured ranunculuses. Around the coral-bushes play the hummingbirds of the ocean — brilliant little fishes, now sparkling with metallic red or blue, now with a golden green, or \\ ith the soft hue of silver. All this marvellous nuinifestation of life is displayed in the midst of the most rapid alter- nations of light and shade, changing with every breath, with every undulation that ripples the sur- face of the sea. When daylight declines, the shadows 164 THE BOTTOM OF THE SEA, of night spread in the deep waters, the exquisite garden which they cover is lighted up with new splendours. The medusae and the microscopic crustaceans shine in the darkness like fairy-stars. The pennatula, which during the day is of a reddish cinnabar colour, floats in a phosphorescent light ; every corner of the sea- bottom sends out its ray of colour ; objects that look brown and dull in the universal radiation of daylight, now shine with the most charming green, yellow, and red light ; and to complete the marvels of this en- chanted night-scene, the large silver disc of the moon of the sea {Ortliagoriscus mola, commonly called the moon-fish), moves softly through the whirling vortices of little stars. The most luxuriant vegetation of the tropics fails to develope so much wealth of form, and lags far behind the magnificent gardens of the ocean, composed almost entirely of animals, for variety and brilliance of colour. That marine fauna is not less remarkable for its extraordinary development than the abundant vegetation of the bed of the sea in the temperate zones. All that is beautiful, marvellous, or extraordinary in the great classes offish, of echino- dermata, of medusae, of polypi, and of shell-covered molluscs bred in the warm and limpid waters of the tropical ocean, repose there on the white sands, at- tach themselves to the rough rocks, or (should the place they covet be already occupied) fasten like SrOAGES. 105 parasites on other existences as wonderful as them- selves, or float on the surface and in the depths in the midst of a vegetation relatively rare."* 5. Sponges. For a long time the zoophytes were taken for in- durated marine plants. Their animal nature, and their likeness to animals under forms and aspects so grotesquely various, were not thoroughly recognised until our own times ; the name they still retain re- calls their apparent analogy to vegetables. The characters of animality which they present endure but for an insignificant period of their exist- ence. At first they move freely in the water, some solid body arrests them in their course, the young animal whose body is sometimes — in the sponges, for example — surrounded with vibratile cilise, attaches itself to the obstruction, where it soon loses all power of movement, and commences a series of strange meta- morphoses. The body, at first gelatinous, breaks into holes, which change by extension into winding canals, traversing the mass in all directions. In these winding channels the water circulates, and brings to the animal whatever substance may be * Schleiden, La Phnte et sa Vie. 166 THE BOTTOM OF THE SEA. necessary to its development. The creature lias lost its mobility, and become to all appearance an inert mass. It resembles a most irregular and ill-formed vegetable ; the holes begin to bristle with liorny fila- ments entangled one in the other, and constituting a kind of solid carpentry. By-aud-by other siliceous or calcareous hlaments mingle with the first, and fill up the cavities which had been left among them. The forms of these are most varied according to the species to which they belong, and often spicula? very different in their aspect are combined in the same individual. They are generally so small that their nature is only discovered by means of the microscope. With its aid some are seen to be shaped like har- poons, some like stakes with pointed ends, some like stars or crystal knots of the most curious forms. The various species of sponge are distinguished by their tissue being more or less close, more or less crooked . Sometimes their mass is surrounded in nearly every part with a siliceous or calcareous envelope. The coasts of Europe furnish some sponges of this kind, but the most remarkable come from the sea of the Antilles and from that of Japan. Sometimes the siliceous spiculse fill the tissues so completely that the sponge serves as a polishing material. The use, how- ever, to which the sponge is generally destined is suggested by the facility with which it takes up I lit,) 1,1.; f STRUCTURE OF SPONGES. 1G9 watei". Most of the s])('cies are unfit for tliat |)ur ])Ose ; they are very minKU'ous, and appear to inhabit indifferently every sea, being more abundant, liovv- ever, near the equator. The Ked Sea, the coasts of Syria, the seas of America, the Middle Atlantic, and the Southern Seas, are rich in sponges capable of seiving for domestic purposes. Sponges are torn from the rocks to which they are attached by divers, who pursue their trade more par- ticularly in the seas of Asia. Should we not feel astonished by the low price at which tliey can be sold, when we reflect that every sponge collected in the submarine forest has been gathered at the risk ot death to one of these unfortunate men, to whom life is nothing but one long agony ? At certain periods of the year certain ovoid or spherical corpuscles are developed in the spongy mass, and thence j)ass into the channels with which the sponge is pierced. Carried out into the sea by the currents of water which circulate in these chan- nels, they propagate the sponge in the manner de- scribed above. When the spongy mass, for any reason whatever, decays or breaks up, the spiculse are scattered upon the bottom. In some seas, such as the Indian Ocean, the sea of coral, tlio specimens of the bottom, taken 170 THE BOTTOM OF THE SEA. from tlie depth ol' about four miles, are principally formed of these spicnlae; tbey accumulate in thick and far-extended beds, the importance of which in course of time, relative to the surface-form of the globe, must be very considerable. 6. Polypi— Their general structure — Eeproduction of Polypi^ Vegetative life of Polypi — The Polypier — Two great classes of Polypi distinguished by the form of the Polypier — The Tubipora musica. Most of the polypi live in colonies, and find a point of support on the rocks. We say live, but more strictly speaking they vegetate, their movements being extremely limited. Their bodies become en- crusted with calcareous matter, and life gradually withdraws from the petrifying animal. Eggs aban- doned to the sea at various periods of the year, or buds developed on the polypus, are two methods equally common by which they are propagated. Tlie body of the polypus is soft ; its form is that of a hollow cylinder; at one of its extremities an opening serves for the introduction of aliment into the body of the animal, and for the expulsion of matters which have not served for its nutrition. This single opening of the body is surrounded with iieshy appendices or tentacles, more or less numerous ; the digestive apparatus, however, is not always marked STRUCTURE OF POLYPI. 171 by tin's simplicity of structure. It is often formed of a double pocket, the one completely enveloping the other. The animal in this case might be well enough described as a sack, closed at one of its ex- tremities, and with its superior or opened part folded back upon the bottom. The tentaculae are always hollow, and all the cavities communicate one with another. Leaf-like formations, or foldings of the envelope of the body close the internal cavity ; the walls of that cavity reunite at the base of the animal. They contract or they dilate at its pleasure, in order to give free pas- sage to the aliment prepared for nourishment in that first chamber. Matters unfit for nutrition are at the same time ejected, by the only door which has given them entrance. Between the wall of this stomach, and the exterior envelope of the animal's body, a sort of double bottom, imperfectly partitioned off, collects the aliments that have been suitably prepared, and it is there that the eggs of the animal are lodged. The spaces left between the foldings of the skin in that second pouch are prolonged into the tentaculae, which the animal can withdraw into itself at will, or spread out like the blossom of a flower. Fig. 29 fihows the polypus in its various degrees of expansion. The entire polypus is enveloped in a great number of 172 THE BOTTOM OF THE SEA. species, with a tough sheath from which it projects itself at will. Fig. 30 represents a number of sucii polypi indrawn — that is to say, with the body of the polypus retracted and hidden under the protecting envelope which surrounds its base. Fig. 29. — Coral with Polypi more or less expanded. The polypi, whose digestive apparatus is formed of a single pouch, are called hydras or sertularias ; those whose digestive apparatus is formed of a double pouch, are corallines, or polypi proper. The inferior extremity of the polypus is the pro- longation of that envelope, but mo e hardened, in TIIK rOlAJ'IER. 173 which, as we have seen, the animal lias power to sliut itself up. It is the point of adherence to the foreign body, to which the polypus fixes itsel^. Polypi reproduce themselves in two different ways — by eggs and by buds. The eggs, or larvae, are lodged on the walls of the only cavity which encloses the body of the animal. At certain periods of the year, they leave the body and float in the water, as we have seen is the case with the sponges also, until they meet with a place upon which they can root themselves. We have already observed that the sponge, during a greater part of its existence, lives a vegetative life. So, when a polypus is once fixed upon a solid body, its base extends. If other animals of tlie same species join it to form a colony, or if it produce buds, the mass gradually increases. Each polypus secretes a matter which, on hardening, becomes horny or stony, and constitutes the polypier, or polypus tree. The nature and form which the polypier gives to the colony serves to characterise the different kinds of animals of this class. An inspection of the polypier constructed by Fig. 30. — Branch of Coial with Polypi indrawn. 174 THE BOTTOM OF THE SEA. polypi, suggests their division into two great classes, a division which has been already indicated by the essential difference we have pointed out in the digestive apparatus of the different species. The hydras grow from the exterior — that is to say, they surround themselves with a horny or stony envelope, whilst they have no interior calcareous basis or polypier. The corallines present a character alto- gether the opposite. They have an internal polypier — that is to say, the hardest parts of the polypus tree are in the interior, and the living bed in the midst of which are the polypi is superficial. One particular kind of polypus, originally from the Indian Ocean, produces a very remarkable polypier. It is formed of tubes in regular juxtaposition with each other, and joined by transverse partitions run- ing from one to the other (fig. 31). It is for this reason called the Tuhijpora musica, or organ-pipe coral. The tubes are placed next to each other, like those of a mouth-organ. In the engraving it is re- presented half the natural size. The organ-pipe coral is of a beautiful red colour. The first naturalist who observed it in the Indian Ocean took it for a colony of great marine worms, and it is only in recent times that its true nature has been luily understood. This polypus is not an ordinary hydra, notwith- ORGAN-PIPE COIiAL. 175 (Standing the tubular form assumed by the hardened envelopes. The i)olypi in tlie tubipora are, in fact, coQipletely independent of one another. When iresh inhabitants are added to the colony, they grow- by placing themselves parallel to tlieir predecessors, to whom thev are attached by transverse partitions. Fig. 31. — Organ-pipe Coral. Each polypus lives and grows in its own tube, and holds no relations with the others, except that of good neighbourhood, when it leaves its abode to spread its snares for the little marine animals. It is not so with the true hydras. In them the hardened enve- lope resembles a continuous canal, uniting all the polypi one with another. At whatever point of the common trunk a bud is produced, the calcareous matter envelopes it, and establishes its immediate relationship with the rest of the colony. 176 THE BOTTOM OF THE SEA. 7. Hydra, type of the Hydrozoa or Hydra Polyps— Extraordinary properties of the Hydra discovered by Trembley — Mariue Hydrozoa. The hydrozoa owe their name to a special type, the hydra, which inhabits fresh waters. The cele- brated naturalist Trembley, tutor to the sons of Count Bentinck in Holland, was the first to re- cognise their nature, in 1740. The remarkable pro- perties which he discovered among these little beings struck the learned of the eighteenth century with astonishment. The flesh-eating habits and the spon- taneous movements which he had remarked among the hydrae led him to believe they were animals, while their appearance resembled that of aquatic plants. Trembley made the following decisive experi- ment. Plants have the property of reproducing themselves by cuttings — that is to say, a branch of the plant being cut off, and planted under suitable conditions, roots develope themselves at the cut ex- tremity, and the branch becomes a plant similar to its parent. As no known animals possessed thLa singular faculty, it was to be presumed that the hydra would not reproduce itself by cuttings. What then was the astonishment of Trembley when he observed, some days after the mutilation of a polyp, each morsel transformed into a complete body. THE UIDROZOA. • 177 Iiaving the same characters as the creature of wliich it had hitely formed a part ! Evidently science had become enriched by the discovery of a new fact. Her chissification had proved defective, inasmuch as an attribute con- sidered as peculiar to plants had been proved by this experiment to belong to creatures of which the animal nature was incontestable. HeuLe, not- withstanding the difficulty of communication among the learned in those days compared with the present time, this new experience was speedily rumoured throughout Europe. Every naturalist repeated the experiment for himself: at first, upon polypi which Trembley sent in his letters, after having had them properly dried ; afterwards upon specimens which they found for themselves in stagnant waters. Keaumur was one of the first. " I declare," said he, " when I saw for t'le first time two polyps gradually form themselves from one that I had cut into two pieces, I could hardly believe my eyes ; and the truth is, I am not yet accustomed to the belief, although I have repeated the experiment a hundred timea over." Soon afterwards, Reaumur began to observe the same phenomenon in various species of worms, and that which had seemed incredible was soon recognised as being but another of the common phe- nomena of nature. N 178 THE BOTTOM OF THE SEA. This is but one example of the fate common to great discoveries. At first, people are astonished by them, and receive them incredulously ; afterwards, as facts accumulate, it seems as if each experimenter had either made the discovery for himself, or very nearly approached it. If the reader has followed, even in a general sort of way, the scientific movement, he will be able to recall in illustration of this fact the new ideas introduced into meteorology by the learned physician, M. Marie Davy ; how doubtfully his first communications upon the general cause of storms was received, how people hesitated in the very pre- sence of the facts by which the exactness of his obser- vations was verified, and how the merit due to the first observer has finally been acknowledged. Let us return to Trembley's hydra. Its body is soft, and consists of one long pouch with a single opening. The pouch is surrounded with tentacles, which in the species we are describing are six in number. On the walls of the membranous sac whicli constitutes the animal, the buds or eggs develope themselves. The latter, having arrived at a certain size, leave their first home and float freely in the w^ater. The buds can either separate themselves from the mother hydra, or remain fixed to her ; in the latter case the same foot or stalk bears two hydras, the one of which is, so to speak, grafted upon the other. TREMB LEY'S H YD II A. 179 Hydras are Ibiiiid in grassy waters, lakes, pools, and canals. The best mean cf procuring them is to take haphazard, from the water supposed to contain them, any aquatic plants, leaves of trees that have fallen into the water, or bits of \AOod which have accumulated there, and to these the hydras will be found attached. They transport themselves from one point to another by swimming or crawling. Trembley has made a special study of three species of hydra. He has named them the long-armed ^^cly- pus, green polypus, and hrotvn or grey polypus (Hydi-a Grisea). Their bodies, which are very contractile, are variously formed. The tentaculae are often immoveable. The ordinary species, including their arms, may reach five-eighths of an inch in length, but other species attain larger dimensions. Ancient writers mention, under the name of hydra, a mythologic animal with seven heads, each of which was reproduced as fast as it was cut off. Trembley 's hydi-a, more accomplished than tbis fabulous animal, formed two perfect creatures when divided. Nor is this all. What does the reader, when made acquainted with the fact for the first time, think of an animal able to turn itself inside-out like a glove without ceasing to live ? Trembley tells us that his hydra undergoes this operation without being in the J 80 TEE BOTTOM OF THE SEA. least degree incommoded. "I have seen," he says, in his fourth memoir, " a polypus turned inside-out, which has eaten a little worm two days after the operation. Others have not recovered their appetite so quickly ; they have been four or five days, more or less, without wanting to eat. After that time they ate as well as other polyps which had retained their proper insides. I have kept a polyp that had been turned inside-out more than two years. His progeny had become very numerous. Once, w^hen I had suc- cessfully turned a few polyps, I was impressed to repeat the experiment in the presence of good ob- servers, that I might be able to cite other evidence than my own in proof of this strange fact. I succeeded so well that others attempted to follow my example. Monsieur Allamand, whom I begged to try, suc- ceeded as well as myself. He has turned many polyps, and some that he experimented upon have remained inside-out and continued to live. He has even done more than this : he has turned polypi again which had been turned some time before, and this although they had eaten after the first experiment. He even found that they ate as well after the second operation. Finally, he turned some a third time, but they died after a few days, without having recovered their appetites. Whether their decease was owing to the operation or not cannot very well be decided." SEA-WltJ':ATHS. 181 The hydra feeds on the larva? of insects. Though less formidable than its mythologic namesake, its natural properties are, to say the least, quite as re- markable. What can be more insignificant to all appearance than a creature so small that its thread- like body cannot very well be studied without the aid of a magnify in g-glass or a microscope ! But what more curious in reality ! And how greatly has the discoverer been rewarded for his devotion to science by the ever-increasing importance of the facts he has made known! It is thus that Nature rewards the labourers who devote their lives to the contemplation of her marvellous works. Hydras proper inhabit the fresh waters ; sea-wreaths or sertnlarise, which have an analogous structure, are well known to those observers of nature who pursue their studies on the shores of the ocean. The buds, which in the case of the hydras proper generally detach themselves from the mother-stalk, remain fixed to it in the case of the sertularian polypi. The result is that a horny polypier is formed exteriorly, not interiorly, the polypi being enclosed in the orifices of the horny envelope. The latter also assumes the most varied forms. It often fixes itself at the bottom of the sea, but also often rests there without rooting itself. The polypier of the hydra proper adheres to the soil by its base. In its 182 THE BOTTOM OF THE SEA. perfection it may be compare 1 to a tree. Marine plants are generally attached to it, and at its ex- tremities are stalks analogous to those of flowers. One entire family of polyps is remarkable for its attachment to a common stalk, which is capable of supporting the colony without fixing itself to the bottom of the sea. The foot buries itself in the mud or sand, or, better still, the polypier floats in the water. This is the family of pennatulae, of which we will mention only three examples — the pennatula, the virgularia, and the veretillwn. The virgularia has a rough resemblance to a pen. The polypier is in the form of a cylinder split length- wise. The principal s^em does not itself bear any polypi, but they are attached, like blossoms, to the short lateral branches which proceed from the stem at equal distances from the top of the polypier almost to its other extremity. The Pennatula spinosa (fig. 32) is destitute ot polyps over the greater part of its surface. They are arranged to the right and left of a large stem, upon fan-like branches. The foot, which serves to fix the polypier in the sand, is shaped like the hilt of a sword. In the VeretiUum ci/nomorium (fig. 33) the polypi are arranged with great regularity over the greater part of the polypier. They are inserted directly in rLWNATUL.E. 18,J the fleshy matter which fills the interior oltlie common stalk. A cylindrical prolongation of the stalk serves, as in the Fennatula spinosa, for the instantaneous Fig. 32. — Sea-pen iPennatulaspinosa). Fig. 33. — ^Veretillum Cynomorium, mplantation of the entire colony in the place chosen for its residence. 184 TJJE BOTTOM OF THE SEA. The pennatulse rank with animals which are gene- rally phosphorescent — that is to say, which emit light in the night. They abound most near the shores of European seas. Cuvier gave them the name of *' swimming polypi " {Polypes nageurs). 8. Actiniae— Sea-Anemones— Sea-Nettles. The actinse, or sea-anemones, though independcint creatures, attach themselves firmly (and for a con- siderable length of time without changing their locality) to the rocks. Adhesion is effected by means of a large and fleshy base, which secretes a glutinous matter, and it depends entirely on the will of the animal. It moves from one situation to another when it pleases, using its tentaculse as feet, or gliding along at tlie bottom of the sea by a move- ment which can scarcely be perceived. The actiniae appear under the most varied aspects, owing to the innumerable modifications of which the tentaculse are susceptible, and to the diversfied cha- racters of the foot itself. We may compare one of these creatures to a flower plunged in water, with petals so soft and flexible that they yield to its slightest movements. At one moment they may be seen gathered together to agitate the water, as a means of renewing its freshness before the mouth ACTINIA.— SEA-NETTLES. 185 which they protect ; at another they contract and disappear before some threatened danger, or they stretch themselves out to seize their ahnost invisible prey. The exterior surface of the actinaria is tliickly set with oblong lance-shaped prominences, terminating in a stylet, rigid and sometimes barbed, to which is probably due the burning sensation produced by their contact. It is from that sensation that this species of polyps has derived the name of sea-nettles. They have been called anemones, from their resemblance to that beautiful flower, and actinia (starlike) from the rays or tentacles which surround the mouth. The coralline polyps are all, like the actinaria, armed with spiculae, of which the forms are most varied, according to the species. Fig. 34 shows the general character of these spiculae. The body of the actinia, almost cylindrical when extended, is contrac- tile. It becomes globular, or almost spherical, when the animal is folded back upon itself. Its tentacles are Fig. 34. then contracted, and almost completely ^Co^ai ^ covered by the tough envelope of the body. When extended they serve to arrest by simple contact the little marine animals which touch them. The actiniae do not reside in great depths. They 186 TEE BOTTOM OF THE SEA. are generally found attached to rocks in the neigh- bourhood of coasts. They are almost all useless, but one species is eaten in Provence and at Nice. It is very soft and of a greenish colour, with brown stains on the body. The extremities of its ten taeniae, often very long, are frequently of a pinkish hue. These animals, unlike coralline polyps, are nearly always found separate from other individuals of their species. While other polypi are for the most part bound to their native place, the actinaria are free to choose their abode, and change it at pleasure. 9. Coral — Miraculous virtue attributed to Coral by ancient tradi- tion — Coral Stone— Coral Plant — Marsigli discovers the Flowers of the Coral — Observations of M. Lacaze-Duthiers. One of the most interesting of the fixed polypi is, without doubt, the coral. Naturalists of ancient times regarded it as a stone, or as the solid axis of a marine plant. Dioscorides thought it to be a marine shrub which hardened on being taken out of the sea and exposed to the air. He even thought it petrified if touched while it was alive in the water. In 1585, the Chevalier J. B. de Nicolai, previous to fishing- coral on the coasts of Tunis, persuaded a fisherman to dive for the purpose of ascertaining whether the coral, in situ, was hard or soft. Contrary to the NA TUBE OF CORAL. 187 opinion of ancient times, this man reported that it was hard. Nicolai, resolved to be sure of the fact, dived himself, and ascertained the truth of tlie man's statement. In 1(371, an Italian naturalist decided that as coral had neither flowers nor leaves, nor seeds nor fruits, it ought to be classed with stones. This idea seemed all the more strange, considering that after the time of Nicolai, a Lyonnese gentleman, named Poitier, had observed, in 1613, the presence of a milky juice in fresh coral, and had demonstrated that it was only necessary to remove a kind of crust to give it the polish and the red colour. Marsigli, in 1706, announced to the Academy of Sciences that he had discovered small white bodies, like flowers, on the surface of the coral. So long as he left the branch of coral in sea-water, the flowers remained expanded ; but they instantly closed when the coral was taken from the water, reappearing as instantly when it was replaced. Without investigat- ing whether these might be animals or not, Marsigli concluded that the coral was a plant. The merit of having discovered the true nature of coral belongs exclusively to a Frenchman, Jean Andre de Peyssonnel, a physician and botanist, whose observations were made on the coasts of Provence and Barbary, at the instance of the Academy of Sciences. 188 THE BOTTOM OF THE SEA. The Museum of Natural History at Paris possesses the unprinted manuscripts which contain the results of his studies of the nature of coral, and of many zoophytes. He demonstrates tliat the coral branch is an aggregation of animalcules, and he compares them to the sea-nettles, whose name was already known. "I have had," he says, "the pleasure of seeing removed the claws or feet of that nettle, and having put the vessel of water, in which the coral was placed, over a fire, all the animalcules expanded. I stirred the fire and caused the water to boil, when the creatures came out of the coral precisely as when one cooks any kind of shellfish."* This discovery was opposed to so many prejudices that it was badly received for some time. Keaumur, whose name was then all-powerful in science, ex- pressed ironically his dissent, without having in the least attempted to test the researches of Peyssonnel, and this probably prevented the publication of a manuscript which would be well worthy of being rescued from oblivion. Numerous other labours in this field of research, among which those of M. Lacaze-Duthiers may be mentioned as not the least remarkable, have made us pretty well acquainted with the nature of coral. It results from the interior hardening of a polypier, * l^aite'du Corail VARIETIES OF CORAL. 183 or colony of })olyps. Thr. supposed crust is simply the newest part, and as it has not acfpiired the consistency of the interior mass, it is not capable of being utilised commercially. The polypi are lodged in the little cavities or hollows of that crust, which they secrete, and which serves them ibr support. 10. Coral chiefly found in the Mediterranean Sea — Various species of Coral — The Coral Fishery — Antipathes, commonly called Black Coral. The coral of which we are here to speak is that beautiful production of the seas with which ladies are familiar among their elegant articles of bijouterie, not the masses which form coral reefs in the Pacific Ocean. It is found in the Me literranean chiefl3^ but also in the lie I Sea. Its chief habitats are in the neighbourhood of Marseilles, on the coasts of Corsica^ Sardinia, Sicily, the Balearic Isles, and near Tunis and La Calle. Tlie last-mentioned locality has for a long time supplied the greater part of the coral of commerce. It is fixed to the rocks by an enlarge- ment of its base. The fishers state that its dimen- sions grow less in proportion as the depth at which it is found increases. It is generally fished in com- paratively shallow waters, ranging from ten to fifty 190 THE BOTTOM OF THE SEA. yards, and is never taken at greater depths than frorc 200 to 350 yards. The colour of coral is generally a beautiful red, but it is found of every intermediate tint between red and white. That fished on the coasts of France owes its celebrity to the richness of its colours. The different kinds are known to commerce under the various names of " blood coral," first, second, and third, &c., according to the shade. White coral is but little esteemed, if we except that kind known as *' Cornell an- white." The coral fishery is chiefiy in the hands of the Maltese, but it is also pursued by the Italians and the French. An idea of the manner in which it is practised on the coasts of Sicily will not be unin- teresting to the leader. The little fleet engaged in the fisheiy consists of small barks, attended by boats which are manned by three or four men, who take up various positions over the coral bank. I'he tackle used is a kind of drag with arms, worked by means of a capstan. Each branch or arm of the drag has a kind of netted sack at the end of it, into which the coral falls as it is broken off. Beneath the centre of the cross formed by the arms, a heavy stone is swung; and the whole apparatus is dragged along the rocky bottom by the forward motion of the vessel and the lifting motion of the capstan operated THE GORQONIDjE. 191 at the same time. When the drag is pulled on deck, the available coral is selected from the mass and cleansed for sale. The occupation is a very laborious one, more especially as it is pursued under the burn- ing sun of the Mediterranean. Black coral, so called, is tlie stalk of a poly- pier of another species, called the antipathes. The polyps are very small, and have six tentaculse ; in the middle of them is the only opening of the creature's body, the internal texture of which is analogous to that which we have already described as common to polypi in general. It derives a certain commercial value from the fact that, in drying, the centre and hardened part of the stalk completely sheds the cortical envelope and the polypi attached to it. II. Gorgons of the old writers — Their animal nature discovered by Peyssonnel, Trembley, and Bernard de Jussieu— The Fan Gorgon — Its cosmopolitan character. The gorgons, so named by Pliny, were originally taken, like other polypiers, for marine plants. Even yet, we are not thoroughly acquainted with their manner of life. By means of the microscope, the naturalists of the last two centuries have been able to demonstrate the existence of these polyps, which uaa beeu legaftleu as iiyj\s'e£^. Peyssunnel, i'rembley. 192 THE BOTTOM OF THE SEA. and, above all, Bernard de Jussieu and Guettard, liave demonstrated their animal nature. The polypier is flexible, in consequence of not :^y:.i^^\^ , Fig. 35. — Portion of the Vnu Gorgon, magnified, being entirely stony. It has, therefore, not been utilised in the arts. It has, however, been GORGOMA VEUTICELLATA. 108 employed in the coDstructioii of small objects requii- ing a substance at once hard and elastic. Gorgons live, like other marine polyps, at th(3 bottom of the sea, or upon marine bodies to which they attach themselves. As is the case with the coral and the antipathidse, a great number of indi- viduals live upon the same polypier. The body is retractile. Generally, it is small ; and, for many species, a magnifying-glass is necessary to distinguisli clearly the animal from the living fleshy crust which surrounds the polypier. The portion of the fan-gorgon represented in fig. 35, shows the polypi in the form of small round tubercles with a hollow in their centre. The polypi are still more apparent in the whorled gorgon [Gor- gonia verticellata). This species has been so named because the polyps are grouped at different points of the stalk, and form at each of those points a whorl of animals all round the branch.* The gorgunidse display the most beautiful colours in the sea, but their hues fade soon after they have been taken from the water, and retain only the pah^ shadows of white, black, red, green, violet or yellow, such as we see in the collections. * The word vertlcellated is employed by botanists to designate the grouping of leaves which grow at the same heiglit upon n brancli arou'id which thry f rni a ,^ort of crown.— Tr. 194 THE BOTTOM OF THE SE J. The poly pier of the gorgonicise is very variousl}' formed in the different species. Sometimes the branches are almost straight, as in the whorled gorgon ; sometimes they cross and interlace in a thousand ways, and give to the polypier the aspect of network, more or less close. The fan-gorgon is a remarkable example of this. The enlarged extremity of its principal stem, denuded of its living crust, is attached to the rock. From this stem spring many hard and naked branches, which, intersecting one \\ ith another, pass into a net- work in which the polypi live. In size the gorgon ida? range between two very distant limits. The smallest that has been studied may be less than an inch in height ; others reach many feet. Some fragments have been seen by the writer, which show that the entire individual was of still more considerable dimensions. These animals live at a great depth, and inhabit every sea. The fan-gorgon is more generally dis- tributed than any other. They most abound in the warmej' waters, as is the case with other species oi polyps. CALCAHEOVS I'OLYVll.US 195 12. The more iictive submarine constructors Astroides — Caryo- phillia - IMailroporaPlantaginea — Dendrophyllia — Occulina, oi Wliite Coral — Meandrina — Fungia — Porites — Milleporje. The purely calcareous polypiers have their prin- cipal seat in tropical regions. These are the species which exercise the most marked iufiuenccj upon the varied surface of the sea-bottom, and which have distinguished themselves as the constructors of reefs and islands. The principal types of this class of polypiers are the caryopliillia, the meandrina, the fungia, and the pentacrini. For a long time these species were confounded together under the general name of madrepores, and it is only during late years that their polypi have been recognised. These polypi bear a very close resemblance to those of actiniae and corals; but tlie foldings whicli we have remarked in tlie digestive cavity are not connected, as is the case in the latter. They generally occur at the base, so as to constitute a central axis surrounded with raliating cells, whicli are only quite separated from each other at the lower part of the animal. Their similarity to the actiniae, already described, is apparent at first sight. In proportion as the polypier grows, its lower part becomes cal- careous, and reproduces in stone the soft structure that had been formed bv the living animal. The 196 THE BOTTOM OF THE SEA, divisioDS of the fissures or cells harden graciiiall}^ owing to the deposit of calcareous matter in the interior of their tissue. It forms little transverse plates, which close the bottom of the cells, bounded by the radiating divisions. When the polyp dies, we discover at the bottom of the place which it oc- cupied a stony polypier, divided by plates which converge towards an axis, and terminate at the upper extremity by forming a little starry cup (fig. 36). Fig. 36. — Dendrophyllia Rnmea, 1. Natural size, with polyps. 2. Magnified, with the polyps dead. The difference between the various polypi of tin's group consists especially in their mole of repro- A^TliEA I'UyCTJFJ'JiA. 197 duction, and in the consequent .'oini of the lolvpicr which they produce. When ti.e individiuds are isolated, or not closely grouped (fig. 37), the poly- pier attains no great dimensions. The caryophillia presents this character, and examples of them are to be found even in European seas. In other varieties the buds do not separate them- Fig. 37. — Caryophillia Cyatims. selves from tlie original stem, but remain an inteiirul part of it as they grow in number and size (fig. TS). They develope side by side, and are joined one to another by a comjiact tissue, which is thus formed into thick masses. The polypier is especially charac- 198 THE BOTTOM OF THE SEA. terised by tlie continuity of each column down to the base. The species of astrea are numerous, more particularly in the neighbourhood of the equator. When the bads in the process of development do not remain parallel with the mother-branch, the Fig. 38. — Astrea Punctifera. polypier takes the form of a tree, more or less dis- tinctly. In this case, the name it bears recalls the vegetable form to which it approximates. The Madrepora ^lantaginea (fig. 39) is formed by the aggregation of small polypi joined together by masses more or less conical in form. To every polypus there is a corresponding little depression, surrounded with a slight eminence. In general appearance the poly^ pier with its polyps resembles a spike of plantain. AUBoAlSCJJXT I'OL Yl'lEUS 199 A deeper separatiun still of tlie polypi, as well as a greater amount of divergence one from another, brings us back to the arborescent forms assume 1 by the coral. Fig. 39. — Madrepora Plantaginea. The dendropliyllia, represented half the natural size (fig. 40), has a massive trunk, bv which it 200 THE LOTTOM OF TlTL: SEA. seems to grow out of tbe lock as a tree out of tbe grouud, and from which the branches proceed in all possible directioiis. At the extremities of the Fig. 40. — Dendrophyllia (half the natural size). branches are the cuplike hollows in which the polypi live. OCCULINA VIRGISEA. 201 A kindred species, tlie occuUna, is remarkable for the excessive subdivision of its branches, as well as foi- their arrangenicnt. The polypi are found both on the surface of the stems, and at their extremities, and every one of them gives birth to a new branch — the whole constituting a very ele- gant treelike formation. The type of the species is the Occulwa virginea, sometimes called white coral. It is common in the Mediterranean, and is also found in the neighbourhood of the equator. No such symmetry as we liave observed in the coralline polypiers is to be found in the meandrina, or brain coral, of which there are some fine speci- mens in the British Museum. The polyps of this species have no tentacles around their mouths, but short lateral ones. They are huddled together in the shallow sinuosities which furrow the surface of the polypier ; bat sometimes they disappear alto- gether, as in a species found in the Red Sea. All that can be discovered in the furrows is a row of mouths. The sinuosities vary according to the species. Their numerous folds wind among one another like a maze, reminding one of the famous Cretan labyrinth ; hence the name given to this species {meandrina, meandering). They are generally globular, or nearly so, in form, and are found of various sizes on i&olated rocks. They are abundant 202 THE BOTTOM OF THE SEA. in the Red Sea,* but are still more frequent in the equatorial seas, where their size and their general aspect have suggested the name by which they are sometimes called by sailors — Nejptunes Brain. A specimen in the British Museum is four feet in circum- ference. Their great size is accounted for by the manner of their formation. " As one ileshy mass ex- pires," observes Dr. Mantell, " another appears and gradually expands, pouring out its calcareous secre- tion on the parer t mass of coral : thus successive gene- ratioris go on accumulating vast beds of stony matter, and lay the foundation for coral reefs and islands." As remarke 1 in Lyell's " Principles of Geology," " We may compare the operations of the zoophytes in the ocean to the effects produced on a smaller scale on land by the plants which generate peat ;Jn which the upper part of the sjphagnum vegetates, while the lower is entering into a mineral mass, in which the traces of organisation remain when life has entirely ceased. In corals, in like manner, the more durable materials of the generation that has passed away serve as the foundation on which their progeny are continuing * " The whole bed of this extensive basin of water is absolutely a forest of submarine plants and corals. Here are sponges, madre- pores, corals, fungise, and other polyparia, with fuci, algse, and all the variety of marine vegetation, covering every part of the bottom and presenting the appearance of a submarne garden of the most exquisite verdure." — Mantell. THE MEANDRINjE. 203 to spread successive accuimilatinns of calcanoiis matter." 'Vhe porites, or po7'itidie, belong to the same group, and are amoTijy the number of polypiers which often attain very large dimensions. Their substance is calcareous. Their surface is riddled with pores, or rather little shallow cups, in which the living polyps 204 THE BOTTOM OF THE SEA. are found. Most frequently the polypier is set with polyps from its foot to its summit, although those at fij. 42. — Millepora Alcicoinis (one-fouith of the natural size). the base may no longer be living. Each of these little animals is marked by the characteristics which .we have notice 1 more than once. The number of THE FUNGIA. 205 tentacles differs in the various species, and is often very considerable. When the polyps are removed from tlie stem, tlie little hollows with their imperfect divisions become visible all over the polypier. The latter assumes tlie most varied forms, according to the manner in which the polyps are reproduced. Sometimes they are most complex and elegant, as in the case of the Millejoora alcicornis (fig. 42). These animals differ from the astroides proper in the arrangement of their polypi, and from the coral- lines in the absence of the fleshy incrustation around the polypier. The polypier is wholly calcareous. Its development is owing to the hardening of the trans- verse divisions of the polypi and of their external covering. Their growth is irregular, and it leaves no trace of the animals themselves except the irregular pores. They are found in the seas of the North and of America. The variety of entirely calcareous polypiers is very numerous. One in particular we must not overlook — the fungia, so called from its resemblance to the ve- getable fungi. The animal of this species is gelatinous or membranous, somewhat oval in form, and much flat- tened. The engraving (fig. 43) represents a mouth in the centre of a large disc, the interior of which is made solid by a calcareous deposit, while the solid core is 20G THE BOTTOM OF THE 8:.A. covered with plates or lamellae, radiating from the centre towards the circumference. Protruding from the disc are a great number of tentacuhe, which the animal Fig. 43. — Fungia Agariciformis. contracts or extends at will from between tbe sharp, thin plates of the polvpier. At the end of each ten- tacle a sucker is represented ; it is used by the animal to capture its prey. DESTRUCTION AND RENOVATION. 207 13. (jrHiley-slaves of the Sea— The Giants and Pigmies of Creation — The Suckers — Legends of Monsters— Singing Fishes. The greatest activity prevails beneiith the surface of the sea. Were it possible to lift the veil, scenes the most varied and unexpected would meet our gaze. Creatures which inhabit the deep would be seen in- cessantly labouring to renew or adorn the earth. Some are engaged in the work of destruction, some in building up. The one class supplies the other with the materials which it fasliions into forms of beauty. Among those we have called destroy erS; the pholas, though it plays an obscure ^part, is very remarkable. It does not browse on the animal flowers of the polypier. It does not play the part of a tiger in the sea, and devour armies of fish. It sim[)ly eats its way into the hardest stones, as the xylophagi burrow in wood. Even the hardness of gneiss is not proof against its patient determination. At first sight we should be disposed to say that no weapon, no tool, aids this indefatigable labourer. The shell has two valves of the ordinary character, turning on a cartilaginous hinge. The body has two openings. Its substance is capable of being elongated so as to form a tube traversed by two channels — one of which serves for the absorption of water, the other to eject it as from a syringe. The soft rounded bo ly 208 THE BOTTOM OF THE SEA. of the animal seems to be furnished with no organ by which even the softest substance could be pierced. It has two teeth, but they are so deeply seated that it is impossible they could ever operate upon the walls of the retreat which the creature bores out for itself. Our attention is directed to the anterior part of the shell, which appears to be set with hard points, so arranged on the surfaces extending from the hinge, forward, as to form a kind of file. At this end, a short foot or tongue is protiuded, by which the ani- mal holds on to the rock, while at the same time it partly turns itself, and thus by the friction of the serrated shell rasps away the chalk or rock. The work commences from the beoinning; of the creature's life. It first makes a slight hollow in the stone, in which it ensconces itself. In that position the water of the sea brings it sufficient food. Little by little, as the animal grows, it enlarges the shell in which it lives, and at the same time buries itself more deeply in the stone. Their advance is made almost horizon- tally at first ; but having reached a certain depth, they suddenly change their direction, and bore out their retreat perpendicularly. It is at once theit dwelling and their tomb, and in form resembles a common tobacco-pipe — the stalk debouching in the sea, and the bowl containing the animal. In the regions frequented by pholades, the rocks THE rHOLADEiS. 200 are thus pierced in every direction. We even see enormous stones bored quite tlirougli, from side to side, by those destroyervS. it was for a long time be- Fig. 44. — Gneiss bored by the Pholades Dactylus. lieved that they effected their lodgment while the rock was in a soft state, and that it afterwards grew hard around them, and enclosed them as in a living tomb, owing to the petrifying virtue of the water. 2J0 THE BOTTOM OF TEE SEA. This opinion was abandoned when it was observed that the columns of the ancient temple of Serapis, at Pozzuolis, VA liich had been submerged for many years in consequence of an earthquake, and again restored to the light of day, had been pierced all over by pholades. Shut up in a prison from which they can never make their esca},)e, these galley-slaves of the sea con- tinue their work of destruction to the end of their lives, and they have only themselves to blame for their perpetual seclusion from society. Without the least care for the morrow, they go on boring their way through the rock, enlarging themselves and their stony habitation as they advance farther from the sea. The open end of this singular gallery is the gate by which the sea washes in all that these animals need for their nourishment, and for which the pholas re- pays the ocean in a perpetual tribute of dust. Every wave carries something into the mine, and brings something away — another and very striking example of the universal work of sedimentation. Rocks too hard to be breached by the waves them- selves, are thus eaten away and scattered on the floor of the ocean by the pholades. For others are the transparent waters, the romantic ocean ravines, or the extended plains of sand and mud. The oyster the solen, and the razor-fish linger in agreeable situa- t'HOSFUUliESCEyCE OF THE EllOLAJ^. 211 tiuns, and enjoy {ibundance of water privilege. The pholades, like other niolluscs, exist in numerous colo- nies, but all the members of tliis great family obey the word of com maud. Their mission is to go for ever forward, extending or enlarging their mine, and leaving oft' work only when they die. Thus employed, their whole lives would be passed in darkness, if nature liad not provided every one of these little miners with a lamp. The pholades are phospho- rescent. This fact was remarked by Pliny, but the cause of the phenomenon remained long unknown. Keaumur observed that if he washed his hands after touching a pholas, the water became phosjjhorescent ; and at the end of a certain time the phosphorescent matter fell to the bottom of the vessel. We now know that the phosphorescence is diie to a liquid continually secreted by the body of the animal. In contrast with these pioneers of the ocean, of these slaves who precede and assist him in the destruction of continents, there is a creature whose fate it is to float incessantly in the water, at the mercy of the most capricious winds and currents. We have already seen (in the chapter on the Colour of the Ocean) that the water holds in suspension a mass of microscopic beings. It is to tlie existence of these creatures that is due the yellowish milky, red. or olive-greeu tint 212 THE BOTTOM OF THE SKA. SO frequently observed. Freyssinet and Turrel ob- served, near the shores of Luzon, an extent of some sixty millions of square yards coloured a bright scarlet. This tint was owing to the presence of an organisation so small that forty millions of indivi !uals occupied the space of a square millimetre.* As the discoloration extended to a considerable depth, it would be impossible to form even an approximate idea of the number of living beings which caused it. Some of these microscopic creatures never develope to anything beyond a little cell surrounded with vi- bratory cilise, unequally distributed over the surface, and serving the creature either as rowers or as an organ for continually renewing the water which sur- rounds it by creating a current. Their mode of reproduction is extremely simple, and, at the same time, admits of their propagation with almost frightful rapidity. About the middle of the creature the body contracts like the division between the two parts of an insect, and the contraction increases until it separates into two. Each part goes through the same process as its parent, continually dividing into new creatures, until in about twenty generations a single infusoria may have engendered more than a million. One generation succeeds another very quickly. If, then, a variety of causes did not conspire * A millimetre is -OSOSTths of an incli. GIANTS A\D PIGMIES. 213 to check their increase, the infusorise would long since hav*) filled the world. When the body of the animal is soft without any calcareous addition, we find no traces at the bottom of the sea of their short existence. But many species are furnished with a sort of shell, the debris of which constitutes tlie greater part of the sand formed on the ocean-bottom. The foraminiferse contribute largely in conjunction with the infusorise to the levelling-up of the sub- marine valleys. Their microscopic remains — not very long known to be so, indeed — occur in such enormous masses that no part of the earth's crust is of greater interest to the geologist. If we compare with the whale, the shark, and other giants of the creation, the modest infusoria?, the fora- miniferse, and the Noctiluca miliaris, of which we find as many as 25,000 individuals in thirty cubic centi metres of water, we shall be disposed to attach very little, if any, importance to the infinitely little. The giant attracts our eyes by his mass and his force, while we often strive in vain to see the pigmies of creation, as we should look in vain for an atom of dust blown by the wind. The giant, however, will pass away, leaving but few traces of his existence. Here and there a bone or a tooth, perhaps a foot- print, informs us of the fact that a monster once 214 THF BOTTOM OF THE SEA. existed whose remains have long been the sport of the waves. The pigmies, feeble when taken singly, are powerful in their multitude. There are great animals in the ocean, but the armies of the infinitely little count by millions. The giants of the deep make their presence felt while they live ; the pigmies of creation are the true world-makers. The first specimens of infusorise were taken from the bottom of the sea by the apparatus of Brooke, when the submarine plateau upon which reposes the telegraphic cable between Newfoundland and Ireland was under investigation. The appearance presented to the eye was argillaceous, but the celebrated Pro- fessor Bailey, of AA'est Point, having studied the speci- mens with the aid of microscopes, recognised numerous calcareous shells in a state of perfect preservation. The average depth of th(; telegraphic plateau is something under 10,000 feet. That depth, though considerable, anr] exceeding the supposed thickness of the submar ine vital zone, is far from marking the limits of the empire of the foraminiferse. Where they cannot live, their spoil, so light, is carried by the ocean-currents, and deposited in obedience to the ordinary pliysical laws. Specimens obtained by soundings made between North America and Asia have demonstrated the presence of their calcai-eoug shells at depths exceeding 6000 yards. DEBRIS OF THE I.SFUSOHIJi!. 215 If we reHect tluit the sand of tlie seas is often almost entirely composed of these little shells, so variously and elegantly formed ; if we rememl)er that they have been accumulated by the action ot marine currents in regions where their force is re- laxed, that their debris meets with conditions favour- able to their preservation in the calm deeps of ocean, who will not marvel at the enormous influence they exercise upon the distribution of the waters upon the surface of the globe ? Yet we may state, on the authority of M. Alcide d'Orbigny, that many of these creatures do not exceed one-half or one-sixth of a millimetre in dimensions. The same authority states that he has found 30,000 individuals in half an ounce of fine sand brought from the Antilles, or thirty millions in a kilogramme. Another learned naturalist, Plancus, has counted about 200,000 in a pound of sand I'rom the Adriatic. The creative power is more wonderfully manifested in these small beings than in the great. The com- plicated organs and the harmonious richness of the most powerful mechanical appliances impress us in the giants of creation. Our astonishment is greater still, perhaps, in face of the pigmies. The sea, in fact, is full of surprises. We imagine all that is mysterious beneath its waters. The furious tempests which disturb its surface and lash the air seem to 216 THE BOTTOM OF THE SEA. assign a limit to the habitable world. " Tlie sea and all that therein is" appears surrounded with a poetic and miraculous aureole, wliich is the birth at once of fear and of superstition. Before our ancestors had dared to launch out upon the boundless ocean, the Mediterranean and its shores were the abode of the marvellous. As man extended the bounds of his empire, the region of wonder and superstition also gradually- enlarged itself. Old records show that the Spirit of the Storms demanded its victims of the first navigators who doubled the dreaded Cape of Good Hope; monsters the most hideous or grotesque were supposed to haunt the coasts of Norway ; and the bottomless Maelstrom had its genii like the rocks of Scylla and Cha- ry bdis. Popular tradition pointed to the existence of islands situated far away to the westward. The report went that, after the conquest of Spain by the Arabs, a certain number of Christians put to sea, and found refuge in the legendary islands, where they built seven cities. At the time of Columbus this sup- posed country bore the reputed name of Sette Citade, and was called by geographers Antilia, which name appears on the maps down to the end of the fifteenth century — together with that of another great island, situate in the latitude of Newfoundlanl, and called LEaJ'JXDAh'Y MARINE MONSTERS. 217 the Isle of Satan. According to Arab traditions, a great hand rose every night from the sea, near the latter island, and, seizing the inhabitants, phinged them into a dark abyss. Myths of the highest anti- quity refer to the Athmtic Ocean as the abode of the blest and the kingdom of the dead, and traces of these legends are preserved even to the present day in Scotland and Ireland. On a certain occasion a tishing-boat, in the northern seas, was engaged in the fishing of bishop -fish and monk-fish. The kraken, a monster of many square leagues in size, rose from the bottom of the sea ; the vessel, receiving a shock as if it had struck on a rock, was sunk with all its crew and equipage. Another form of monster, dreaded by the fearful and superstitious, had immense suckers and arms; a huge mouth in the mi<]st ol' his tentaculse swallowed all that he could seize ; his arms were supposed to be hundreds of feet in length, and so powerful that they could enfold and crush ships of considerable size. The gigantic poulpe, or devil-fish, and the sea- serpent, have been the subjects of the most marvel- lous stories, which in our day have been reduced to their just value. These terrible monsters generally resolve into immense cordons, or vast fields of algae, interlaced one with another, and waving hither and thither at the men-y of every breath of wind which 218 THE BOTTOM OF THE bEA. stirs the waves, or with the feeblest motion of the ocean-currents. The giant poulpe has yet to be discovered. We find, indeed, on rocky coasts, in the rugged fis- sures and caverns of the ocean, the well-known devil- fish, liideous enough truly, resembling a sack with serpent-like arms surrounding a horrible mouth. With these arms the poulpe seizes his prey in a far from agreeable embrace, and sucks him, as a spider does a fly, before swallowing him, so as to enjoy at his ease the juicy flesh of his struggling victim. These horrible creatures will sometimes attack man, though, generally speaking, they avoid him. In all the recordel instances, however, the danger and the horror have been exaggerated. An adventurer bold enough to thrust his arm. into one of these glutinous sacks may turn it inside-out like a glove, and, con- trary to what we have observed in the fresh-water hydra, the marine monster will not survive the opera- tion. In one other respect it is very inferior to the hydra of mythology, for its arms are very far from possessing the power of recoil after a wound ; if they are separated from the trunk, the collapse is instan- taneous. The calmars appear to reach much larger dimen- sions than the poulpes : they are sufliciently formid- able to be dreaded by the savages who traverse, in THE CALMAU.^TIIK RAY. 219 their light cniioes, the waters which they frequent. These animals will seize with their arms a light boat and overthrow it if tlie tentaculae are not cut away with a hatchet. The French corvette Alecion encountered a gigantic calmar in the waters of Teneriffe. The animal was secured by means of a harpoon and a rope, but the head with its tentacles dropped into the sea while it wixs being drawn on board, owing to the rope cutting through the soft flesh of the creature. Marvels have been recorded even of the teeth, the skin, and the spines of certain species of fish. The hooked spines of the ray have almost invariably inspired terror. According to ^lian and Pliny, the wounds made by the sting of the ray are incurable. The former relates that a thief who was making off with one of these fish was wounded by its spines, and died immediately. In our day fishermen have no fear of it at all. The Japanese consider that the best possible remedy for the bite of serpents is to rub the place with the spine of this species of ray. Many of the Japanese carry it about with them for the purpose, but, strictly speaking, to possess this virtue it must have been cut from the living fish and applied fresh to the wound. The negroes believe that the sting a( the ray is venomous, but thev have no more reason for this 220 THE BOTTOM OF THE SEA. idea than the Japanese have for their notion that it serves as an antidote to the bite of serpents. Side by side witli the legends, often of terrible import, to which the sea and its inhabitants have given birth, we meet with others of a ludicrous character. Such is the belief, which prevails in the North of Europe, that the Anatifera concha engenders the barnacle-goose. The barnacle, as all the world knows, attaches itself to rocks, the shells of oysters, and other testacea — to any solid body floating in the water, especially to the hulls of ships, and to submarine telegraphic cables. The protecting envelope of this animal is com- posed of five distinct parts. Through two opposite openings the antepi.ap or tentacles pass out; they are very supple, and covered with filaments; from another part protrudes the foot, which is analogous, in its external aspect, to the branch of a polypier. By this the creature fixes itself to solid bodies. In the midst of the tentacles is a kind of trunk, in which is a thin tongue, rolled into a spiral form, and of a deep colour. The trunk or trumpet-like process is transparent, and formed of a series of rings, diminishing in diameter from the base to the other extremity. The tentacles serve as a kind ol net for seizing prey. When the barnacle Is taken from the water, it TUE EARNACLE-GOOSE. 221 quick] y dries up, and to such a degree that, after some days, it is very difficult to fiud among the shells the remains of the shrivelled animal. This has probably given rise to the belief in the marine origin of the wild duck. The canard rising from the water has broken its shell, and left nothing but its debris on the shore. Experience and reasoning are powei'less in face of this prejudice. If the rustics of the North cannot say they have seen the canard leave the shell, the only reason is, they would answer, that it is hatched during the night. Fabulous legends of this kind have hidden the true facts in a surrounding of incredible circum- stances, owing to the strong inclination for the marvellous which has characterised young nations and oriental races. The sea was, in olden times, peopled by sirens who played a great part in naviga- tion. Unlucky was it for the voyager who had too great a liking for art and beauty ! Charmed by the perfidious but sweet songs of the siren, he became the sport of fantastic illusions ; he saw imaginary coasts, and was wrecked on invisible rocks. The siren is a fabulous being. But harmonious sounds float over the ocean, though perhaps they are only those made by the sobbing of the waves, by the suash of the water against the ship's sides, or against the bulk of some great fish. 222 THE BOTTOM OF THE SEA. Without reflection, it might appear that no other sounds than such as these contribute to the oceanic concert. Fish do not seem to possess any vocal organ, and if their throats were better adapted for the emission of sound, it is doubtful if we could hear their songs. Let us remember that sound results from the vibration of some elastic, gaseous, liquid, or solid body — that sound travels more rapidly in water than in air. Considering that the celebrated physicist Cagniard-Latour has constructed a little apparatus, by the aid of which sounds are pro- duced at will, in the air or in the water, and which for that reason he calls the siren, we need not be astonished to learn that many fish emit sounds, and that in some instances these sounds assume the character of true singing. Without sneaking particularly of the coineoin, whose grunting ^cis oeen compared to the cry of a wild goose ; of the vieille, which utters a plaintive cry when it is seized ; or of the tunny, which wails like an infant when taken from the water — let lis listen for a moment to an account of a discovery not many years ago in America. The narrator, Mons. 0. de Thoron, was walking one day on the shore of a bay situated to the north of the province of Es- meraldas, in South America. All at once, when the gun was setting, he heard with astonishment an SOUNDS HEARD AT SEA. 2,i3 indefinable soun.l, very sonorous and long sustained. In that country, where the insect race is often very troublesome, he thought at first that the sound proceeded from insects of unusual dimensions. Failing to discover anything of the kind in the air, or on the sea, he questioned a man who was rowing by, and was informed that the sound proceeded from a fish, called by some the siren- by others the musician. M. de Thoron, desirous that no other sound sliould interrupt his enjoyment of this phenomenon, re- quested the boatman to rest on his oars. All around a multitude of sounds rose from the sea, forming the most singular concert it is possible to imagine ; the undertone of a church organ heard at a considerable distance might be said to resemble it. The concert commenced at sunset, and continued all through the night. The presence of auditors, ]M. de Thoron ob- serves, did not ceem in the least to intimidate this new species of choristers. They build, they feast, they make love, they steal ; they live in captivity, in freedom, or are enslaved in the ocean. As Fredol says, " There is joy in its waves, there is happiness on its shores, there is a pervading bliss throughout all !" Animal life displayed in the most opposed forms, the most grotesque organisa- tions, appears in greater beauty than on the withered earth. Tribes of living creatures rejoice incessantly 224 THE BOTTOM OF THE SEA. in the most marvellous variations of light and shade, in the most fairylike illuminations, changing and reversing at every instant. They almost talk, they murmur their complaints, they sing, they get up concerts of which we can form but a feeble idea. What then is wanting to the completeness of life in the Ocean ? — Only Man. 14. Algse — The untrodden Forests and Prairies of tlie Ocean — Animal Life more abundant than Vegetable Life — Sea Plants less widely distributed than Marine Animals — Influence of Light — Collection of Seaweed on the Coasts — Assistance afforded by the Tide. Marine vegetable life is very far from equalling in richness the animal life of the Ocean. The marine llora is limited almost entirely to one class of plants — namely, the algae tribe. These plants assume the most strange and grotesque forms imaginable. The number of species seems almost unlimited. The learned Linnaeus counted only fifty, but at the present time at least 2000 are known. As we have remarked in an earlier chapter, the marine flora is developed to the greatest extent in the temperate zones. Its extent and variety may be appreciated from the fact, that in English waters, 105 genera and 370 species of algae may be counted. The richness and variety of this class of plants diminish gradually as we recede from the temperate EXTENSION OF LIFE IN THE OCEAN. 225 zones towards the equator or the poles. '' It is, more- over, remarkable tliat the hxw under which the animal kingdom, which more readily adapts itself to surrounding circumstances, becomes more extensively developed than the vegetable kingdom, applies to the ocean as well as to the land. Thus the polar seas abound in whales, seals, fish, and aquatic birds, and are populated by an infinite multitude of inferior animals, when all vegetation has disappeared from this region of ice and cold. This law is also found to apply as we descend deeper into the ocean, for in so doing we discover that vegetable life disappears much sooner than animal life: indeed, in abysses where hardly a ray of light can penetrate, soundings still demonstrate the presence of living infusoriae." We know what life does, although we know not what she is. There is no region of natural phe- nomena to which this remark applies more forcibly than to the ocean. We there see animals blooming, 80 to speak, in the most brilliant and varied colours, like flovy'ers, and flowers almost without colour. On the other hand, the animals lose their power of motion, and become more allied to the algae them- selves. Modern investigations show that, during the first part of their existence, vegetable cells have the motions characteristic of animal life, so that the algae might almost be considered as varieties of Q 226 THE- BOTTOM OF THE SEA. polypier, linking together the two kingdoms ol nature. But the algae do not petrify like the poljrp, to whose labours we owe the existence of the coral reefs of the Pacific ; they remain soft and flexible, at the same time establishing immense colonies of their kind. What striking objects, what prodigies, do we iind in each step of our submarine investigations ! Is it matter of astonishment that in the presence of these marvels man's mind should have invented that fairy mythology, the memory of which has been partly perpetuated by the legends of the middle ages? Marine plants are sometimes microscopical. Their floating millions sometimes colour the sea; among others, the Red Sea owes its name to such circum- sta ces. At certain seasons of the year, this sea swarms with filamentous confervas of a beautiful purple colour. The beautiful tint which has from a remote period given thissea the name of Eryth rasan, is due to the infinite numbers of the marine con- fervse. In other cases marine plants attain gigantic dimensions. The Wellingtonia gigantea is no dwarf in size, but what comparison can there be between it and the Vareo 'porte-]poire of Terra del Fuego, which grows to a height of 1 000 feet ! IMarine plants have no need of earth. They grow TliEEiS WITHOUT HOOTS. 227 anywhere., as their nourishment is not obtained from tJie soil, but from the sea itself. For the same reason they have no root ; indeed, the species which float have not even the semblance of roots, while those which remain stationary are attached by a species of sucker more or less lobed or divided. The earth goes for nothing in their development, because their origin is always exterior. Their whole growth is in the water, which supplies all they need, and to which all ultimately return. Land vegetation would not find sufficient subsistence in the atmosphere ; it requires a soil, and trunk, and branches. The alga is supporteil by the water on which it feeds ; it is held down by the rock or earth to which it is attached ; if it becomes detached, instead of falling like a tree, it rises and floats on the surface of the water. As terrestrial plants yield a resting-place for the eggs of birds and insects, so do seaweeds for marine animals; but, instead of supporting them, it prevents them from rising to the surface, and also shelters them from the voracity of the monsters of the deep. As the insect tribes establish their republics in the trees of our forests, so the sponges attach themselves to tiie light algae, and the polypi take them for their iVagile base. Even the sea-worm, like the terrestrial serpent, winds its encircling length around the stems, the better to seize its prey. 228 THE BOTTOM OF THE SEA. How strange a tree would look which, torn up by the tempest, should rise through the atmosphere and float above the clouds ! Such phenomena occur continually in the ocean. The marine currents detach plants of all kinds from the bottom of the ocean. They collect in parts of the ocean where the currents are weaker. There they form immense floating islands, which sometimes hinder tlie progress of ships. Light is as necessary for marine plants as for terrestrial ones, and this prevents them from living at a great depth ; still they grow niany hundred feet below the surface, where light penetrates but feebly. Shells are distinctly visible in certain parts of the Arctic Ocean at a depth of 460 feet ; at a depth of 940 feet the light is still of sufiicient intensity to permit the obj; cts to be seen dimly. The bottom of tlie sea is equally visible at the same depth in the Antilles, but the objects are not distinct. Abso- lute darkness prevails at a depth of 1000 feet. The rays of the moon penetrate only to a depth of about 40 feet. It is, therefore, within a limit of 1000 feet in deptli, or about one-tenth of the average depth of the seas, that marine plants vegetate, forming a belt around our continents and islands, or crowning the summits of submerged mountains. Has light any influence on the colour of vegetation DISTRIBUTION OF THE ALGJE. 229 in the sea ? jModern botanists have proved, experi- mentally, that plants are very sensible to the action of light, and it has been fonnd that marine plants are of different colours, according to the depth at which they grow. They have been divided, according to their pre- vailing tint, into three main sections : the brown or black (melanospermea), the green (chlorospermea), and the red (rhodosj)ermea). The green live only near the surface ; they often float, and are found in large quantities in the grassy seas. The red are found at small depths on rocks near the coasts. The brown, which are much more numerous, grow at greater depths. They constitute the greater part of the submarine forests. Although the algae occupy, relatively, but a small portion of the earth's surface, being distributed in what may be called oceanic belts, their number is immense. Wherever the physical conditions are favourable to their development, they fill the sea with their impenetrable masses. This abundant vegetation is utilised by man, whom the sea itself aids in collecting them. Wind-storms sometimes produce terrible effects, but oceanic storms far exceed them in destructive force. If the first over- throw enormous trees or immense edifices, the latter easily tear whole forests of marine plants fiom their 2 BO THE BOTTOM OF THE SEA. feeble hold of the soil or rocKs. This madness of the ocean is man's gain. On tlie various coasts, and especially in the bays of the ocean, he collects the seaweed which is thrown ashore by each tempest, and even by every tide, in quantities which may be called incalculable, and yet the supply seems never to diminish. There are bays in which 30,000 people are sometimes occupied in gathering this spoil. Seaweed makes very bad fuel, but it is occasionally used for firing. Its most important use is as manure, or as the raw material of soda, which is extracted from its ashes. A still more curious application of it is made by the Dutch, who use seaweed in con- structing the dams which preserve their lands from the inroads of the sea: tlius the ocean itself fur- nishes the materials which are to be opposed to it as an obstacle. Alas! we know too well that the courageous efforts of the inhabitants of the country must at last fail, and that the sea will again assert its dominion over the earth and the ephemeral works of man ! MAN AND HIS WORK AT THE BOTTOM OF THE SE.S. I. The Empire of the Seas denied to Man — Numerous attempts at Submarine Exploration — Disturbance of present social conditions which would ensue from the possibility of travelling beneath the Surface of the Water — The Sea the best tie between Nations. Air is necessary to the life of man ; his organisa- tion forbids a too protracted stay beneath the surlace of the water. If he dives he is soon compelled to return to the surface. He is, therefore, unable to acquire any extensive acquaintance with the sub- merged part of the earth, for no sooner does the depth exceed a few feet than some special apparatus becomes requisite. The explorations which have been made, however, besides their theoretical im- portance, have resulted in great commercial gain. What enormous wealth has been engulfed in the sea since man first dared its dangers, and entrusted his treasures to its fatal grasp 1 Each year a further tribute is levied by the moving torrent of waters, which yields up, here andthere,an insignificant portion of its spoil, but jealously guards the more precious 232 THE BOTTOM OF THE SEA. treasures in its secret bosom. How could the faintest hope exist that the mighty ships laden with rich merchandise, which have sunk beneath the surface, could ever again be recovered ? What man so daring as to attempt their extraction, piece by piece, from the ocean which hides them with such jealous care ? Every such enterprise wa3 for long considered merely chimerical. Even now, any attempt of the kind is, in most cases, impracticable ; and in those rare instances where some hope of success may fairly be indulged, it is only by great sacrifices, and by the exercise of much ingeni* Ity, that our expectations are adequately realised. In presence of the vastness of the sea, man is in- voluntarily impressed with mingled respect and terror. He may sail about on its surface boldly enough, but he penetrates its depths with hesitation. In his pursuit of a marine monster, he liarasses it so long as it imprudently remains near the surface of its vast empire. No sooner, however, does the monster feel the power of his enemy, and the danger of remaining within his reach, than he sinks, though only a few yards, down into the abyss of waters, and man's power of pursuit immediately ceases. If nature had gone so far as to endow man with a large reservoir, where, like the whale and other sea- monsters, lie could store up a sufficient volume of AUDACITY OF EXPLORERS. 2:53 air, and carry it with him to the farthermost depths of the ocean, what service could he extract from so marvellous a provision, if his eyes, constructed so as to give him the power of vision in a limpid and dazzlingly luminous atmosphere, made him conscious only of darkness, and left him a defenceless prey to the voracity of the monsters of the deep ? But man is ambitious to assert his sovereign right over the whole globe ; universal nature is his inheri- tance, and he studies her every phase and all her changing humours with patience. In his thirst for knowledge he fearlessly grapples with, and seldom fails to overcome, wliatever obstacle may be thrown in liis path. With a sublime audacity he would penetrate and master, in every direction, an empire the limits of which appear to him to be too narrow. He is not satisfied to run with lightning-speed over the surface of the earth ; he would also cleave the air like a bird, and dispute their darkest and dreariest retreats with the inhabitants of the seas. As if conscious of her irresistible attractions, the Ocean allows him occasional glimpses of her treasured charms, and, at the same time, one might almost say that she defies him to deprive her of any portion of them. Corals, sponges, and pearls have to be snatched from her depths. The magnificent purple of the ancients — sepia, mother-of-pearl, ambergris — 234 THE BOTTOM OF THE SEA. are but a few of the valuable substances which are well known to be of oceanic origin. Ambition and the love of gold are an almost uni- versal motive power. Poverty and fear often supply their place. The first attempts at circumnavigation were made by daring sailors imbued with a desire to make a rapid fortune. Sponges and pearls were long procured exclusively by the labour of slaves. In many parts of the world the old fashion is still fol- lowed, insofar that diving is the only means employed to obtain those treasures of the deep. The process is of the most primitive kind. On reaching the scene of his labours, the adventurous diver detaches the sponge from the rocks to which it is fastened ; nets are suspended from boats and sunk within reach of the workmen, who fill them with their spoil, and, on a signal being given, the well-laden nets are drawn up by a cord. Edible oysters inhabit the European and Indian seas ; they are very abundant on the French and English coasts. Oyster-fishing is carried on by means of a net furnished with a scraper, which is dragged over the rocks to which the oysters are fixed. The oysters detached from the bottom are accumulate 1 in the net. together with any other animals which ac- company them. A.S Goldsmith relates, the unfortunates condemned DIVERS AND THEIR PERILS. 235 to the painful and laborious occupation to which we have referred on the coasts of Persia, are either the negroes or the poorest of the inhabitants. Divers not only rim the risk of drowning, and of being de- voured by sharks, but they are also in danger of being suffocated in consequence of having to hold their breath for a protracted time ; and if no worse effects ensue, this condition often results in blood- spitting, llie most robust and healthy young men are chosen for this trafle, but they can seldom con- tinue in it for more than five or six years. Their fibres stiffen, the pupils of their eyes become red, and they often die of consumption. . . . They deposit the pearls, or rather the oysters which contain them, in boats 28 feet long, of which there are often 300 or 400 at sea at one time. Each of these boats has seven or eight stones, which serve it as anchors, and on board are from five to eight men, who dive by turns. They are all naked, but have a net sus- pended from their necks, into which they throw the oysters; their hands are gloved, to preserve them from the wounds which they might otherwise get in detaching the shells from the rocks. They descend with the help of a cord, to which is attached a weight of about 50 pounds. They place their feet in a kind of stirrup ; with the left hand they hold the cord, and with the right they close the nostrils, to prevent 236 TUK BOTTOM OF THE SEA. the exit of the air, of which they have taken a deep breath previous to their descent. Having reached the bottom, they commence operations by giving the signal to those who remain in the boat that they may raise the stone, after which they set to work collecting the shells, with which they fill their nets as speedily as possible ; they then make another signal, upon which the net is raised, and immediately afterwards they themselves rise to breathe. All the shells are carried to the shore, where they are piled in heaps until the fisliing-season, which lasts during November and December, is at an end. The holothuria, or trejpang, much sought after in Asia, is gathered by divers, or harpooned on the bodies to which it attaches itself. The harpoon is fixed to the extremity of a series of long bamboos fitting one within another. Leaning over the bow of his boat, the fisher gazes into the depths of the sea ; the most perfect calm is indispensable, and it is as- serted that in such case he can see, at a depth of 100 feet, the animal attached to the rocks or coral banks ; the harpoon descends as gentlj" as possible until it reaches the animal, when it strikes it sud- denly, and rarely in vain. In the greatest number of instances the diver de- scends as far as his sight will permit him, but this y to a slight depth only Modern apparatus facilitates iiii lllllillillilllll|lllllll|IIIIIIIIIIIIIM|l|l lllliM^ SUBMARINE VESSELS. 239 Ids expeditions, but it has not much extended tneir radius. In fact, the pressure supported by toe in- trepid explorer augments by one atmosphere when he has reached a depth of 32 feet ; it soon becomes so great as to involve conditions in which it would be impossible to live. Asphyxia, ravenous monsters, and darkness, are not therefore the 'only obstacles which man has to encounter in his submarine explorations. He cannot descend into the immense oceanic valleys as he faces the cold and rarefaction of tlie air on the high mountains of the terrestrial surface. Beyond the region of the monsters he must enter the realms of darkness, and, should he go further still, encounter sure destruction. Who can form an idea of the immense changes which would result if men were able to travel freely under the surface of the waters? Where would be the natural frontiers which politicians so much desiderate ? Man darting through the air like a bird ; locomotives competing with the eagle in point of speed, and losing themselves in the midst of the clouds; powerful machines plunging beneath the oceanic tempests, and scattering in terriHed hosts the multitudinous inhabitants of the sea! Who would dare to entertain for one moment dreams or aspirations of so chimerical a nature ? (J-reat mindb have nevertheless devoted their labours and thoughts 240 THE BOTTOM OF TEE SEA. to .«inch obiects, and we shall presently see bow tbey tiave partially resolved the question in respect to the Ocean. Sailors of a new order may now be shipped ior submarine expeditions ; the adventurer can already carry with him a provision of air, light, and food ; lie can sink or rise at will, or maintain himself at any particular depth, like a spirit of the deep ; he can suddenly make his presence felt in the midst of a fleet, or on a hostile coast, before the astounded enemy has time to prepare for defence ; he can discharge his powerful batteries and engulf himself in his adopted element, like a true marine monster, while they seek in vain for the cause of the disaster with which they are suddenly smitten. If a few steps have been made towards the realisa- tion of such marvels, how many more still remain to be accomplished ! It will perhaps never be man's lot to tread the hitherto unfathomable abysses of the sea ; the hum of civilisation will never disturb the profound peace which the monsters of the deep are themselves bound to respect. At any rate, there must be patient waiting through a long series of ages for this result, and we must leave to our descendants the care of adding another chapter to the history of the 6df th. They may perhaps see cultivated lands, forests, and mountains, where the present level of the sea per- mits only a wild waste of waters ; or perhaps they may, THF ;SEA AXD ITS SPOILS. 241 in digging their roads, canals, and tnnnels, study the deposits now in conrse of actual forniation, whilst coral reefs, sponges, and oyst<'r-bauks will cover the edifices of which we are now so proud. Without descending to any great depth, we may see even near the surface and the coast, in the midst of reefs which seem to permit man to penetrate the oceanic waste but to forbid his return, submarine life conspire with the waters to bury out of sight the evidences of the destruction they have wrought The nations would be rich if the sea did not levy a heavy tribute upon them. But the sea only corrodes and wastes the spoil it seizes ; the abundance of oceanic life engulfs it a second time. Molluscs, bar- nacles, and seaweed very readily attach themselves to bodies plunged into the sea. Ships which make long voyages sometimes become loaded with so enor- mous a cargo of shells and barnacles, that they re- semble floating aquarii, and lose much of their speed. The work of the sea is incessant. Every hour, every minute, adds to the thickness of the covering with which she conceals her thefts ; and so long as the methods of search remain as imperfect as they are at present, we must be content if we recover oocasion- ally such fragments only as this fascinating monster is willing to render up. ■ We are prevented by a variety of causes *roni 1 242 THE BOTTOM OF TEE SEA. exploring by far tlie larger portion of the earth's crust- Nature has been jealously careful to remove it from our sight, to preserve it from our unappeasable curi- osity. Should we not congratulate ourselves on this fact ? And does not this water, which hides so many marvels, serve now, and has it not always served, to human need, as one of our most powerful auxiliaries ? It is water which most facilitates the relations that are established between the inhabitants of different countries, which invites to exchanges and transactions of all kinds, and is in fact the soul of commerce, of which civilisation is the offspring. Though flourishing on the coasts, civilisation pe- netrates but slowly into the interior of continents. By the sea it is speedily transmitted from shore to shore of neighbouring islands, and so on to the re- motest. On the continent it spreads slowly, step by step, and its progress is almost invariably paral- lel with the cdurse of rivers and streams. Ee- move the water, and civilisation would disappear; the desert would again reign supreme ; one waste of sand would cover everything with a moveable shroud, like the waves of the sea, but even more terrible. Hrv many have paid with their lives for the avJacity which impelled them to penetrate the secrets of the desert ! To all who have the courage to confide in her. the DIVING APPARATUS. 243 sea provides a means of transport at once agreeable and convenient. The sea supports tlie load, tli(^ wind propels it, and man directs it on its journey. From this easy means of transport results a great commercial movement, a circulation of ideas ap well as products, which enlarges the field of inrlusiriai genius, encourages useful inventions, promotes that affability and those humane feelings which spring from much intercourse, and, in a word, developes relations between one people and another which could not otherwise be established. Further, the discoveries of sailors, the voyages to distant countries, to very different climates with varied productions, the rapidity of exchange, and the wellbeing which results, are the first step towards that universal union which is the end and aim of all civilisation properly imderstood. 2. Exploration of the Bottom of the Sea — Diving Apparatus — In- vention of MM. Eouquayrol and Denayrouze — Submarine Electric Illumination — Salvage of objects sunk in the Sea — A Chest of Gold recovered under peculiar circumstances in thr Fort of Marseilles. The exploration of the bottom of the sea made but little progress in ancient times, or in the middle ages. During many centuries the few attempts of which we hear are ratber of a legendary thnn 244 THE BOTTOM OF THE SEJ. authentic character. We can scarcely be astonished at this when we picture to ourselves the profound ignorance which prevailed relative to the properties of gases. Aristotle, for example, wishing to demon- strate the weight of atmospheric air, weighed an empty bladder, and the same bladder again when filled with air, and found no difference between the two results. Hardly three centuries ago, the fact of water rising in the tube of a pump was explained by the supposition that Nature abhors a vacuum. It is hardly a century since the celebrated astro- nomer Halley, commencing the experiments in sub- marine exploration which have been continued to our time, descended to a deptli of 50 feet in a diving-bell which he had constructed. English engineers utilised this invention until the year 1830, in building the immense submarine structures with which they have covered the English coasts. At this time another apparatus, more convenient and at the same time less costly, gradually replaced the diving-bell. The object of the diving apparatus, to which we are now referring, is to give to each individual work- man the utmost possible liberty of movement. An impervious habit, made of cloth and metal, allows him a certain liberty of motion, which he cannot possibly have when enclosed in a bell. A pipe com- RECENT INVENTIONS. 245 niuiiicating with the interior of his clothing supplies him with the air necessary to respiration. This air is supplied by a lift and force-pump, placed on the bank or in a boat. This apparatus is of French origin. Attempts of a different kind were made, at the end Fig. 46. — Divers dressed in the Apparatus inveuted by MM. Rouquayrol and Denayrouze. of the last century, by an inhabitant of Breslau. A. diver descended into the water carrying his supply of air in a reservoir, into which large quantities of 246 THE BOTTOM OF THE SEA. this gas had been compressed. The man cg,rried this reservoir on his back, and it communicated with his mouth by a tube. Mhurr also made attempts to improve the appa- ratus in France, but without superseding the original invention. In England some form of the apparatus was constantly used, and, in 1830, the discovery of caoutchouc gave a great impulse to this industry, and improvements became more feasible, at the same time that they were more necessary than ever. This was the state of affairs when two Frenchmen — M. Eouquayrol, a mining engineer, and M. Denayrouze, a naval lieutenant — solved this difficult problem. Their apparatus suffices for all the exigencies of sub- aqueous work. Whether the man be naked, or covered with impervious clothing, his respiration depends entirely on the exercise of his own will, aiiu on the power of his lungs. This result is obtained by means of an artificial lung or supply-regulator, which consists of a reservoir made of steel or iron, capable of resisting very great pressure, and surmounted by a chamber so constructed as to regulate the afflux of air. The diver carries this apparatus on his back. A respiratory tube issues from this chamber, and is terminated by a mouth- piece composed of a piece of sheet-caoutchouc, which is held between the lips anf'i the teeth of the diver. AN ARTIFICIAL LUNG. 247 This pipe is furnished with a valve, whicli permits the expulsion of air, but opposes the entrance of water. The steel reservoir is separated from the air-chamber by a conical valve opening from the air-chamber towards the reservoir in such a manner, as to open only by the influence of an exterior pressure — the pressure of the air in the reservoir tendins: to close it. It is obvious that the use of this apparatus renders the regular working of the air-pump unnecessary. The air which it transmits to the diver is stored up in the steel reservoir. From this store the diver can supply his needs without fatigue in the following manner. The air-chamber is closed by a moveable lid, to which is attached the tail of the conical valve. The diameter of the lid is somewhat less than the interior diameter of the chamber, and it is covered with caout- chouc to render it airtight. It yields to both interior and exterior pressure — the former causing it to rise, the latter to fall. When exterior pressure is exerted on this lid, the valve is immediately affected through the in- termediary tail or rod ; communication between the reservoir and the air-chamber is opened, and a portion of the compressed air flows into the chamber. Should the latter contain an excess of 248 THE BOTTOM OF Till': SklA. air, the pressure of it against the moveable lid keeps the valve closed. The entire apparatus, when under water, works as follows. By drawing in his breath, the workman re- moves a certain part of the air from the chamber ; exterior pressure is then immediately exerted on the moveable lid, vvhich falls, and through the intermediate rod causes the valve to open. Air issues from the reservoir, and re-establishes the equilibrium between the interior of the air-chamber and the surrounding medium ; the lid rises, and the conical valve, returning to its former position, again intercepts the communi- cation between the reservoir and the air-chamber, until another aspiration brings about a repetition of these phenomena. When the workman respires, the valve, which we have already mentioned as existing in the respiratory tube, permits the air expelled from the lungs to escape into the water. This apparatus works automatically ; whatever be the irregularity in the working of the air-pump, its action is as regular as that of the steam-engine. The workman receives exactly the quantity of air necessary for respiration ; this air reaches him at a pressure equi- valent to that to which the rest of his body is submitted, and he is able to breathe without attention or effort, MM. Eouquayrol and Denayrouze, not content with having enabled the workman to breathe independently SUPPLY OF AIR 249 of the action of the pump, have considerably improved the latter apparatus by constructing pumps in such a manner that the leakage decreases, until, as the pres- sure increases, it can scarcely be appreciated. It is well known that air becomes hot simply by being strongly compressed. The supply of air in the heated state is injurious to the divers. The pumps of which we speak, and in which the air traverses two layers of- water before entering the steel reservoir, remedy this inconvenience. Moreover, the air, in passing from the steel reservoir into the air-chamber, from whence the workman is supplied, expands again and becomes still cooler. Another important advan- tage connected with this apparatus is that the expired air rises in bubbles to the surface. So long as the diver breathes regularly, the intervals which separate the appearance of the bubbles are sensibly equal. If they come more rapidly or more slowly than usual, it IS a sign that something abnormal is going on. If they cease altogether, the diver must have ceased breathing, and should be hauled up immediately. In the old diving-dress the air filled the space be- twixt the body of the diver and his impervious clothing, the expired air escaping by a little valve fitted into the helmet. But the excess of air trans- mitted by the pump also escaped by this valve. Ir- regularity in working the pump would therefore 250 THE BOTTOM OF THE SEA. cause irregularity in the escape of the bubbles, and if the pumpers continued their work they might, quite unconsciously, for a long time continue to send air to a corpse. With the new apparatus, however, the escaping air affords constant evidence of the health of the diver. The moment he requires help, his at- tendants are on the qui vive, while in the former case they could know nothing of his condition. This ad- vantage in the new apparatus can hardly fail to en- courage the most timirl. Further, he who wears the old apparatus exposes his life much more than he who uses the apparatus of Rouqiiayrol and. Denayrouze. His life, or at least the security and duration of his labours, depend en- tirely on the strength and. substance of his clothing. In the new system the caoutchouc dress serves only to protect the diver from the cold. It requires, therefore, much less solidity than the other, and thus leaves the diver greater freedom of motion. MM. Eouquayrol and Denayrouze have done everything to bring their incontestably useful ap- paratus within the reach of all. Experienced and intelligent divers are no longer requisite — neither is it necessary to employ workmen accustomed by long practice to work the pump in a uniform manner. We have already seen how the diver is enabled to obtain a regular supply of air in spite of any irregularities PRECAUTIONS NECEHSARY. 251 in working the pump. The substitution of a simple mask, in place of the helmet hitherto in use, allows the dress to be closed hermetically with much greater facility, a single bolt effecting this completely. There are, nevertheless, several precautions neces- sary. If these are not observed, the miners run risks which are, to say the least, disagreeable. The pres- sure to be supported increases by one atmosphere for every 32 feet of the depth. The workman's body is therefore under a pressure of about four atmospheres when at a depth of 100 feet, whilst at the surface he would be under the pressure of one only. A rapid transference from one pressure to another so different cannot be effected with impunity. But the body will gradually become accustomed to these new physio- logical ronditions, if the man begin by descending a few feet, and increasing the depth day by day. Even with this preliminary training, each descent should be made very slowly. The return should be even more slow ; and to avoid all inconvenience, it would be well to allow about one minute for every six or seven feet of rise. If these simple recommendations are not followed, much suffering may be caused — such as singing in the ears, and headache. The workman must be trained gradually, as is the case in all bodily exercises. The liofht is verv feeble beneath the water, and 252 THE BOTTOM OF THE SEA darkness increases with the depth, soon becoming such that the workman has to grope his way about- more especially where the bottom is muddy, and in parts where it is impossible to see beyond a depth of t\\ elye or fifteen feet. To remedy this serious incon- venience, attempts have been made to use an oil or spirit-lamp, and even a simple lantern lighted with a candle. A pipe, communicating with a pump, is needed to convey the air necessary for combustion ; another, rising to the surface, permits the escape of the pro 1 nets of combustion. Witliout referring to the inconvenience which was generally felt in working these lamps and their two pipes, the light was always found insufficient. The dense air transmitted by the pumps gave rise to the singular phenomena to be observed in compressed air-tubes ; the wicks car- bonised, the light was pale, and lasted hardly a quarter of an hour. These difficulties have been overcome by employing the electric light. A per- fectly watertight lamp of iron or brass encloses the regulator of an electric light on Serrin's systein. The wires which conduct the current enter the lamp by traversing a non-conducting plug of tow. The current is derived from a pile of fifty elements, and a dazzling lioht, equivalent to two thousand of Carcel's jets, is obtained. The sides of the lamp resist the pressure exerted bv the water, and the gases, becoming dilated SUBMARINE LIGHT. 2r>\i by tlie heat, escape by means of a little valve analo- gous to that used in the artificial lung-. The regularity of the light thus obtained depends only on the regulator itself, and not at all on the depth ; it will maintain its energy for about three hours, and then it is only necessary (o change the carbon-points. Fig. 47. — Divers finding a Box of Gold in the Poi t of I\Ini>eilles. Divers are very geneially employed to recover tilings which have fallen into the sea. How many valuable objects have been rescued from the oceau 254 THE BOTTOM OF THE SEA. \yj' this means, in spite of the mud or sand which had ah-eady commenced to cover them up ! The diver, with the equipments we have described, makes his investigations in perfect safety and ease ; he can see quite as well as in full daylight ; he examines every cranny ; he overturns the soil stone by stone ; he maps out his field of operations, and thus saves him- self from a useless repetition of his search. His patient investigations are rarely without some valu- able result. In the excellent description of the Eouquayrol-Denayrouze apparatus, we find the fol- lowing remarkable example of a salvage effected by the help of this apparatus : — " The packet-boats Ganges and rimperatriee came into collision in the outer port of Marseilles. The Imperatrice had one of her wheels broken, and the officers' quarters damaged. One of the cabins con- tained a chest full of gold, which fell into the thick mud which forms the bottom of the port of Marseilles. It was important that this precious package should be recovered the next day. The sea was rough, and the exact spot where the accident occurred, unknown. The box was not strong, its colour was black. At the supposed spot a plumb of 60 kilogrammes was sunk. This plumb carried two cords divided into meters ; two divers dragged them in separate directions, and, taking each the knot coiTesponding to one meter, ymrS RAISED AT SEBASTOrOL. 255 they described consecutive circles, examining the ground at each step. After seeking three liours, tlie gold was found and restored to its owner, who had watched the operations with intense anxiety. Tliis fsalviige was effected on February 19, 1867, by M. Barbotin, contractor for submarine work at Mar- feeilles." 3. Gowans Salvage of Russian Vessels in Seliastopol IJaibour. An American engineer, named Go wan, lias recently effected a much more important salvage, by ex- plorations of the bottom of the sea of grea^ter mag- nitude than had ever been attempted before. Prince IMentschikoff, closely besieged in Sebastopol by the Anglo-French army, perceiving that the weak point of the fortified town was its roadstead, and that the enemy's fleet was about to force an entrance, sank a line of ships and frigates in the passage between Forts Catherine and Alexander. A second line of vessels was sunk to fill the gaps create 1 in this sub- marine barrier by the autumn storms. At last, when the hour for the Russian retreat had arrived, he dis appointed his conquerors by sinking all that remained of the fleet, with the exception of a few solitary barks, in the bay, the muddy bottom of which was now the bed of at least 100 vessels, representing in value some fourteen millions sterling. 256 THE BOTTOM OF THE SEA. The vessels thus sunk had been treated in sach a manner as to resist as much as possible the dele- terious action of the sea ; any part likely to be de- teriorated, such as the engines and all metallic fittings, being covered with tar or tallow. Peace being concluded, tbe struggle was commenced be- tween man and the sea. Gowan equipped himself as a diver, visited and examined the half-buried hulks of tlie ships, and determined that the sea should yield the sunken vessels; some, he was of opinion, might be recovered entire, others piece by piece. An enormous pump, raising nearly 1000 tons per minute, was used to withdraw the water from the in- terior of the vessels, the portholes and other openings of which had been previously imperfectly closed. This powerful machine emptied the hulk of a sub- merged vessel in a very short space of time. The lightening was so sudden, that the vessel rose to the surface before the water had time to re-enter by the various openings left. An enormous chain, 1000 feet in length, each link in which weighed 150 kilo- grammes, served as an auxiliary to this pump, or when necessary replaced it entirely. To conclude, a detach- ment of divers was occupied in seeking for detached portions of wreck, much of which was already half- '^'•uiied in mud. I't^iilllM^^^^^ iMI'ii1llli'il!ililllJ|||||||llJlllJlll!lllllllll!ll!lil!illi;(ll(li)ll BEPAIHING SHIPS. 259 4. Ships repaired without leaving the Water, and even while under Sail. We havealrea'ly mentioned the great utility of the diving apparatus in recovering sunken treasure, and in submarine masonry ; but its utility is much greater to the sailor when it becomes desirable to clean or repair the bottom of his vessel. Every day increasing importance attaches to the parts of the vessel below water-mark. Seagoing steam-vessels, especially, re- quire the frequent employment of submarine work- men. The apparatus formerly used, when the life of the man depended simply on the strength and con- sistence of his dress, was but little adapted to the rude bufifetings of the sea. The improved diving- dress which we have just described is far from pre- senting the same inconveniences. To clean or repair the bottom of a ship it is no iongei- necessary, as heretofore, to lay the vessel up in dock, and thus incur great expense, as well as the loss of valuable time. A rope-ladder, with rungs ot wood or iron, is passed under the vessel. The ladder having been stretched tight, the diver descends, and clings to its rungs by means of a triangle, the base of which is iron and the two sides of rope, terminated by an iron hook. This renders the use of his hands unnecessary to his support. He may fill his airtight 260 THE BOTTOM OF THE SEA. clothing with air, and ihus be in a manner floated against tlie overhanging sides of the ship and sus- tained without any trouble. Tlie American monitor Miantonomoli returned from Cronstadt seriously damaged ', the sailors of the Fig. 49. — Caulking a Ship while undex* Sail. American frigate Colorado repaired tlie vessel in Clierbourg Roads, during rough weather, in the space of five days. Cruising in the Mediterranean, the same vessel received fresh damage in a pipe at the I'JXrh'KlKXCi:S of DJ.VEH>. 2U1 sfeiu. The sailors, provided with the iin[)r.!ved ;ij)- paratus, repaired the [»i[)e in seven hours. It is very important to keep the bottoms of vessels cleansed while they are on a voyage, especially in hot climates. If the apparatus were emph)yed by passage-boats, a great economy of coal would be ef- fected. In 109 hours of labour beneath the water, th(^ armour-plated ram Taureau, which had been afloat four months, and the bottom of which was thickly coveied with seaweed, little shells, and muscles, was completely cleansed ; its speed, as ascertained immediately afterwards, was 12J knots — a high rate of sailing for a vessel of that class. 5. Sensations of the Diver — Depth to whicli it is possible descend. There is a limit beyond which it is very dangerous, not to say impossible, to descend. This limit is at the depth of about 200 feet. The diver at that depth is subjected to the pressure of seven atmo- spheres, and any trifling incident might endanger his life. The reader will find a curious example of this in the Annales de Sauvetage Maritime (May, 1866):- "On February 17, 1865, about 3 o'clock in the afternoon, a steamer on fire was sighted off Usha^'t, 262 THE BOTTOM OF THE SEA. The vessel was low down in the water; it was dis- masted, and had lost its boats ; it sailed under a top- sail, gallant, and jib ; the other sails hung in shreds from their ropes Instead of anchoring in Stifi' Bay, situated west of the island of Ushant, towards which it appeared to direct its course, this illfated vessel got entangled in the rocks between one of the points of this bay anri the Men-Corn, and very shortly grounded. The sailors were seen to run about the deck as if they were mad. The sea was lumpy, wind violent in the extreme; no help could reach them from the land, as neither a rope nor the means of throwing one on board could be procured. The rising tide soon floated the vessel, now deprived of her rudder, however, which had been broken on the rocks; and being at the mercy of the winds and cur- rents, she drifted into the Helle channel. It now appeared that she had sprung a leak, as her stern gradually settled down, and an hour afterwards the vessel was wholly engulfed, just as darkness hid her from view. This ship was the Columhia. " Left Molene on the 31st of August, at half-past 4 in the morning. About 11 o'clock the pilots grappled what they believed to be the Columbia. The Flambeau moored herself by four anchors as nearly as possible at the spot indicated. A sounding taken by the captain gave 180 feet as the depth to the KxrEHii:sci:s of divehs w6 dock of the wreck ; the lead indicated pit-coal, red lead, and black paint The bottom to the south- east of the ship was about lOO fe t ; to the north- west about 230 feet. The northernmost anchor was at a depth of 250 feet. The four anchors were laid down by 1 o'clock. While the men dive we pre- pare the battery and the lamp, which burns well in the air. The pumps and other apparatus are got in order. At 25 minutes past 3 the diver, Deschamps, has his mask fitted on. '*The following is his own description of the impressions he received in his two descents : — *' First Trial. — He descends step by step, resting at intervals, and receiving and transmitting the signals with regularity. At the fiftieth step, water enters by the back valve, which he closes a little ; at the sixtieth he closes it entirely ; at the hundred-and- twentieth (130 feet) the water enters by his front valve, which he closes a little. He asks for more air. At the hundred-and-sixtieth step (180 feet) he makes a rather longer pause ; he shuts his valve still closer ; the air issues only by bubbles. He counts 174 steps ; the ladder does not reach the ground; he can feel and distinguish the cast-iron weights which serve to stretch the ladder; he hangs by them and rests his feet on the ground — a soft sand, into which he sinks. Just as he stoops to pick 264 THE BOTTOM OF THE iSEA. up something white, like a pebble, he feels himself raised with great rapidity, and his ieet strike against each rung in the ladder ; he holds the ladder with one hand, but cannot succeed in grasping it with the other. An accident has happened to the pumps, and he has not been in any way conscious of it. At the fiftieth step he loses sight of the lamp and wires ; they had appeared to him like ordinary thin brass wires. On touching the ground he felt the water enter at his right foot. " Second Trial. — At the fortieth step, water enters by the back valve ; he screws it up a little, and is obliged to close it at the sixtieth. At 160 feet, water enters by the front valve, which he holds nearly closed. At 195 feet, water enters by his leg; he closes the valve and rests on the sand, in which his feet sink. The pressure is general over the whole body, and is exerted on the bladder, which empties itself involuntarily. This effect had also been produced with less intensity when he reached the ground the first time. He detaches one end of his guide-cord; he can distinguish this cord, the weights, his hands, and he advances a few steps. He has great difficulty in withdniwing his feet from the sand, to which he feels rooted. All at once his sight is obscured, his head turns; he returns in- stinctively to the ladder, and asks to be i-aised. He EXPERIENCES OF DIVERS. 205 begins to ascend as well as his streno:th will allow ; feels himself impeded by his guide-cord, which he cuts ; and then rises alone very rapidly, having lost his senses. A violent shock brings him to ; he recognises the sides of the ship, against which his mask has struck, and regains his courage. He waves his hand over the surface of the water, and feels him- self sinking. His mask having got displaced, the collar almost chokes him. He feels himself seized by the arms, and grasps a rope which his hand ha| - pened to touch. He again loses consciousness for a moment in the ship's boat, and asks to be raised on deck as soon as his mask shall be unscrewed. He suffers much from the right hand, breathes with difficulty ; his extremities are cold, and neck painful. Twice he nearly faints, and ceases to breathe. His sight appears troubled, everything turns round with him, and his gaze has no steadiness. " We unanimously concluded that the state of the diver and his apparatus proved that neither could work with regularity under a pressure of six atmo- spheres, and that it would be very imprudent to expose the lives of men by causing them to work under this pressure. The diver wished to repeat th<^ attempt, but neither the captain nor the engineers would permit him to do so. The above experiments «^how that the diver may breathe, tiiat his organs 266 THE BOTTOM OF THE SEA. may remain in their normal state, and he may pre- serve his presence of mind, to a depth of 13v) feet ; but when he exceeds this depth by 10 or 20 feet, the external pressure causes physiological effects on his organs independent of his wilh One hundred and thirty feet is therefore the depth which experi- ment shows to be the greatest at which any hope can be entertained of performing any prolonged submarine work. . . . Within this limit, security to life is perfectly compatible with the conditions in- volved in an attempt to recover any ship or sunken treasure which will pay the necessary expenses. (Signed) " Carvallo." 6. Extreme diflficulty of working below Water — Submarine founda- tions — Stone worked when in position. It appears from what we have stated above, that, notwithstanding all the efforts of genius, we cannot penetrate the oceanic abysses. Nearly all that we can do must be done on the borders of the vast ex- panse. Nevertheless, our visits to the sea, though limited, have a great theoretical and practical im- portance, of which we have already cited numerous examples. The art of diving is almost indispensable in build- ing submarine constructions. What great work can SUBMARINE MASONRY. 267 ft man perform who works in the '^ark, casting his materials nl iiost liaphazard into the lap of an ele- ment which fie dares not or cannot grapple with? Would his labours be much more valuable if lie had to dive and leave the water every instant, throwing only a coup d'oeil over the work which he could not wait to improve or advance ? When, by continuous efforts, and by the use of an immense amount of materials, man shall have built up a foundation in the bed of the sea, he will still find himself continually arrested by the difficulty of making permanent progress at the surface. In calm weather his building goes on apace ; he is proud of it, and regards the sea as a subjugated enemy. But the furious waves of a sudden tempest breaks down his work as if by enchantment, as if it had deter mined to crush man wdth the greater humiliation for having allowed him sufficient respite to make such arduous progress. The beautiful breakwater at Cherbourg, one of the most gigantic of modern undertakings, had been thrown down many times by the sea before it stood in its invincible strength to form an impassable barrier to the fury of the waves. Such works were formerly built by casting into the sea at the chosen site a vast number of immense boulders, stones, and concrete, piling them up in the irregular pell-melJ 2G8 THE BOTTOM OF THE SEA. fashion attributed to the giants in the fable when seeking to scale the heavens. These works are now effected with less precipitation and infinitely inore studied circumspection; enormous blocks are built one upon another, upon which the sea may exercise its utmost fury in vain. These blocks are Fig. 50. — Sinking Blocks of artificial Stune at Cherbou;g. manufactured on the spot, by filling enormous rec- tiUK'ular caissons with a kind of coarse concrete, which hardens by contact with the air, and j.ar- ticularly with water (fig. 50). WORKS AT CHERBOURG. 269 When tne block is sufliciently solidified to bear submersion, the mould is removed and the block is sunk into the sea. But the diver must have first prepared the Ibun latious of this cyclopean wall on a periect level. Provided with levers aud other tools, he raises the block, and places it in the exact position indicated by the engineer. U'he care demande 1 bv Harbour g'^s^^^s^^^ F Level of llic S(a at liidi-tide. Fig, 51. — Vertical Section of Breakwater at Cherbourg, A. Iiockvvork of loiigh stones, D. Foundation of artificial stone. B. Unwrought blocks. E. Wall laid in hydraulic mortaj-. C. Blocks of squared stone. F, Granite facing, this process renders it necessary that the divers should be continually descending and ascending, in order to examine the work on all sides. Furnished with the apparatus we have described, they can, by means of a simple tap, fill or empty their caoutchouc -ar/O THE BOTTOM OF THE SL:A. clothing of the air it contaiDS, and thus make it answer the purpose of a swimming-bladder. They may manoeuvre in the most varied manner when beneath the water by simply turning a tap. The blocks of stone are thus built up with as much regularity as on dry land, and are capable of oppos- ing the greatest possible resistance to the incessant attacks of the waves. 7. Diving Bells — Stationary Compressed-air Apparatns. Previous to the invention of the apparatus which we have now described at some length, diving-bells were employed in the construction of jetties, fortifica- tions, lighthouses, docks — in a word, in all important submarine work. This invention consists of a large cast-iron bell, communicating, at its upper part, witli a force-pump. Invert a common drinking-glass in a basin of water ; the air diminishes in volume as the glass is sunk further in the water ; indeed, its bulk may be seen to decrease by the gradual rise of the water in the glass. The air collects in the upper part of the glass, and becomes gradually more compressed — preventing the water, however, from completely filling the vessel. Make a communication between the bottom of the glass and a reservoir of air compressed to the same DIVING BELLS. 271 extent as that in the ^lass, the water still leiiiaining at the same levtl. Compress this someuhat muiv, it drives the water from the ghl^s, which it fills. This is precisely what happens in the cliving-belh Fig. 52.— Diving Bell. AVhile the bell descends the workmen are supported on transverse benches. Having reached the bottom, the air from the pump drives out all the water from the bell, and the men can then leave their seats and commence work. As they cannot leave the bell^ 272 THE BOTTOM OF THE SEA. the field of their operations is necesstirily limited — an inconvenience which is remedied by moving the bell laterally. In fact, this inconvenience is only nominal when, as is often the case, the labour consists in making an excavation in one particular Fig, 53. — Fixed Apparatus, supplied with Compressed Air. spot. In such cases the diving-bel] may be even advantageously replaced by apparatus employing compressed air, and of such a form as the conditions of the work demand. It was by the exercise of CO.MSTEUCTWN OF BRIDGElS. 273 ingenuity in this respect that the magnificent bridge over the Khine, near Strasbourg, was so rapidly con- structed. Each of the piers of this bridge rests on a founda- tion composed of four iron caissons of large size and weight. Each caisson was open at its lower part (Hg. 53). The uppei- part supported three shafts, a middle and two lateral ones. All three rose above the surface of the waters of the Rhine. The middle shaft communicated with the open air, and the water rose in it to the general level of the river. It enclosed a dredging-apparatns worked by a steam-engine. This dredge, as well as the shaft itself, descended to the bottom of the river. The workmen loaded the compartments of the dredge, which discharged its load into the river. The two lateral shafts terminated at the upper part of the caisson. The workmen first shut them- selves up hermetically in the upper part of the shaft, which they afterwards put in communication with blowing-machines. The compressed air driven by these machines gradually expelle I the air from the shaft, and ultimately from the caisson, into which the workmen would now descend and coinnience their excavations, carrying the debris to the dredges. When the workmen wish to leave, they first mount to the upper part of the lateral sh.ift ; the action of 274 THE BOTTOM OF THE SEA the blowing-machine is then gradually lessened, so as to diminish by degrees the pressure of the air they breathe. The water rises at the same time in the caissons and lateral shafts until it has attained the level of the river. The dour is then opened and the men leave their prison, which may be regarded as a species of diving-bell, but of a form devise 1 for a special service. 8. Payerne's Submarine Hydrostat The diving-bell proper lias been much improved by M. Payerne. His *' Submarine Hydrostat " possesses the immense advantage of being capable, at the will of those enclosed in it, either of floating on the sur- face, or of sinking or rising, as may be desired. Thirty men may work in it with ease for a number of hours without inconvenience. It is therefore oj great service in clearing port'^, and in facilitating the execution of other submarine work. The principle of the machine is very ingenious. Externally, it has the appearance of one large rectangular box, surmoanted by another smaller one, completely closed in except at the bottom. The interior of the hydrostat consists of three principal compartments. The lower, or hold^ is open PAYEKNE'S HYDROS! AT. 275 below, as just stated, and communicates by a large ohiiimey, or shaft, with the upper compartment, or hetween-declis. Between these is a third compartment, or orlop-deck, which only commuiiicates with the others by means of stopcocks. All round the lioM and the orlop-deck runs a gallery, hermetically closed, and connected with the former compartments by stopcocks only. The lower part of the gallery receives the ballast of the machine, whilst the upper is filled with air or water as occasion requires. (Fig. 54.) Whilst the hydrostat floats, the hold and one por- tion of the shaft are full of water; the orloj)-decJc, iU gallery, and the hetween- decks being full of air. A lift and force-pump are found in the latter, where the workmen would now be stationed. When it is wished to sink the hydrostat, the hatch of the l.t'tweeu-decks and the door of the shaft are closed hermetically. The pump is worked in such a manner as to draw water from the exterior, and fill tlie orlo[)-deck and its gallery. A pipe furnished with a stopcock allows communication between the upper part of the orlop-deck and the hold. At the same time that the latter is filling with compressed air, the apj^aratus fills with water, gets heavier, and ultimately sinks. '1 he water which was in the hold has, it is true, been expelled ; but the contents of 276 THE BOTTOM OF THE SEA. this compartment are equal to that of the orlop-deck. The hold was originally full of water, but now both the orlop-deck and the gallery are full. The work- men now open the door of the shaft and descend into the hold, having the bottom of the sea for a Fig, 54. — Payerne's Submarine Hydrostat. floor, and the scene of their labours. One or two remain in the between-decks, there to store away the excavated material, and work the pump when necessary. PAY ERNE'S HYDItOSTAT. '277 When they wish to rise again to the surface, the men re-enter the between -decks by the shaft, which they close hermetically. The pump is worked so as to withdraw the air from the hold, and transmit it to the orlop-deck and gallery. The water escapes by the pipe communicating with the exterior. The hydrostat becomes lighter as the hold fills with water, and soon floats on the surface as before. The men then open the hatch, and obtain communication with the outer world. The hydrostat is removed from one spot to another by towing. The hold is square. It measures about 26 feet in the side, by 6 feet 6 inches in depth. The orlojp-dech lias the same dimensions. The hetween-decJcs has the same depth, but measures only 16 feet in the side. The hydrostat is, therefore, nearly 20 feet in height, and its base, which has the bottom of the sea for a floor, covers an area of 625 square feet. We have already stated that an airtight gallery surrounds both the lower storeys. This gallery, like the orlojp-dech^ is divided into a number of smaller compartments, which can be made to communicate, or kept distinct, by means of stopcocks. M. Payerne's submarine hydrostat resolves several difficulties at once. By interior arrangements, as we have seen, it may be made to rise or fall at will, and it will readily float about like a raft. This ingenious 278 THE BOTTOM OF THE SEA. machine has ah-ea'Jy been put to the test. The port of Fecamp was choke I up vvitli shiugle, wliich closed it against all vessels beyond a certain tonnnge. The hydrostat was employed, and the port cleaned and again opened to commerce. The cases m which it might be employed with advantage are obviously very numerous. Ports are more generally ma le by digging vast basins in the neighbourhood of coasts than by seeking to enclose portions of the sea by means of jetties. The work is more easily and quickly done in the open air, and there is not the probability that the sea will overturn it at any moment. The port enclosed by hills, or the natural port, has the double advantage of giving shelter both against wind and wave. But if the port fill up gradually, if its mouth become obstructed by mud or sand washe 1 up by the sea, the hydrostat may be a Ivantageonsly employed. 9. Yilleroy's Submarine Ijoat. What ingenuity has been brought to bear on the construction of submarine engines, both for purposes of destruction and investigation! Boats to sail l)e- neath the water, diving-bells and dresses, submarine fireships and torpedoes, are all so many evidences of the activity developed in the human mind by the sea. riLLEROY S b I BMA h'JNE BOA T. 9.7- M. YiDeroy, a Froiidi engineer, constnicte;! at Philadelpliia, a few years ago, a remarkable macliin(% intended to swim at any de[)tli beneatli tlie surface of the sea that its conductor nii_ht desire. This sub- marine vessel ^^as shaped like a cylinder, with conic.. I Fiff. 55. — Villt^rov's Submarine Boat. ends. It was closed hermetically. It was lighted by a large number of circular windows cut in its iron skin, and closed up with thick glass. A hatchway allowed ingress and egress. Gutta-percha tubes, placed in the interior, communicated with the exterior 280 THE BOTTOM OF THE SEA. by means of a conduit-tube furnished with a stop- cock. By means of a pump the vessel could be filled with water at will. To cause the vessel to sink it was only necessary to allow the water to penetrate these tubes ; its ejection caused the vessel to rise. A screw worked at the stern. Viileroy's structure \Aas 35 feet in length, and 44 inches in diameter. The screw was 3 feet in diameter. By lighting the bottom of the sea by means of an electric light placed in the interior of the vessel, a convenient method of exploration would be obtained, at least in the neighbourhood of the coasts. This vessel, built during the American war contem- poraneously with the production of the monitors, which may be said to have saved the North from the humiliation of defeat, is a worthy companion of the torperlo — that terrible instrument of war, which, in a moment of supposed security, is capable of destroying the most formidable ship of war with even more cer- tainty than a tempest. 10. Employment of Torpedoes in clearing Channels smd the p]n trances to Ports. In our age — which may be called an age of progress, «nu*e it has witnessrd the dovelonment of so manv TORPEDOES. 281 ideas which illustrate the fraternity of men, and tlie solidarity of their interests, without ^vhich we are little superior to the brutes — liow many instruments of destruction have been converted from their original design in the interests of our common humanity, and applied to beneficent purposes! Manby in England, and Delvigne in France, have transformed the cannon into an instrument for the salvation of life, so that the destructive missile is hurled through the air as a messenger of liope to the shipwrecked crew, by carrying the thread on which depends their safety. In the same spirit, Tixier has employed the torpedo as an instrument of salvation. The Dunkirk Pilot mentions an opera- tion, the perfect success of which leaves no doubt of the happy results we may expect from the ser- vices of this terrible yet docile auxiliary of man. The schooner Virginie, of St. Malo, sunk at the entrance to that port by the steamboat Zingari, was partly broken up by a torpedo exploded in its hold by M. Franpois Tixier, who undertook this operation and brought it to a successful termination. The various phases of the explosion, up to the time which would elapse between igniting the Bickford fuse and the result itself, had been previously indicated with remarkable precision, which the result fully confirmed, and which was attested by numerous 282 THE BOTTOM OF TEE SEA. spectators. The explosion, which caused a tremen- dous upheaval of the water and pieces of wreciv, accompanied with quantities of sand, was received with acchimations by tiie spectators, as a demonstra- tion that the expectations of tlie operator had been I'ig. 56. — Removing an Obstruction by means of a Torpedo. fulfilled. This experiment proves that we have, even now, an important addition to our means of removing the debris arising from disasters similar to the above, the number of which has increased greatlv of late vears. The whole of the wreck may REMOVING OBSTRUCTIONS. 283 thus be removed piecemeal, until tlie passage shall have been completely cleared, and the possible cause of many serious accidents removed. It is seldom that so powerful an instrument as the torpedo is necessary, but submarine blasting is often resorted to ; and, in such cases, a diver comes into requisition. He directs the apparatus, worked either by hand or steam-power, and prepares the ground for the introduction of the destructive agent. When the hole is made he inserts the iron vessel filled with powder or nitro-glycerine. He covers it with cement, and places it in communication with the shore, by means of conducting wires for the electric current, or a fuse which will burn under water. The diver then retires. Either the fuse is lighted, or an electric curj-ent is sent through the wires, and the explosion takes place. At great depths the action of the powder is pro- digious. Compressed by a column of water, the gases exert an increased force on the rock (if that be the nature of the obstruction), and tear it in a thousand directions. At the surface there is scarcely any indication of the concussion below, except a slight agitation of the water. Dead fish float about the scene of action, and a hollow sound is heard. If, however, the depth of the water be slight, the explosion causes the projection of a jet into the air, 284 TEE BOTTOM OF TILE SEA. and the rock is less affected by it. For this reason, vvliere there is a tide, the operators await the period when it is at its highest before tiring the charge. This precaution is more than ever necessary where the rock is broken up, and it is sufficient to take advantage of its natural crevices and employ a charge applied in bottles. 11. English Mines beneath the Ocean. Man's submarine labours are not limited to the surface of the sea-bottom. Nature hides some of her treasures beneath the sea as well as beneath mountains. Coal, iron, tin, and other minerals are often obtained from great depths. A vertical shaft affords communication with the horizontal galleries from which the mineral is extracted. At several points of the English coast the miner does not hesi- tate to carry his galleries beneath the sea, at the risk of being drowned, if the least fissure permits the ingress of water. But this danger is also en- countered in ordinary mines, for the immense bodies of water known to exist in the crust of the earth would be much more than sufficient to destroy, in an instant, the most gigantic subterranean works. The enterprise is not, therefore, so hazardous as might appear at first sight ; it presents in other cases about MINES BENEATH THE OCEAN. 285 tlie same amount of difficulty. Fire-damp is as dangerous, and its effects are as disastrous in the one case as in the other. Kindled beneath the sea, it soon bursts its rocky barriers ; the fire spreads, an ex- plosion destroys the walls of the subterranean chan- nel, entire hills are lifted or overthrown as by a volcanic eruption. It is of little consequence to the Fig. 57. — Section of a Tin Mine in Cornwall, miner that this catastrophe takes j^lace under the sea ; the danger is not greater than if it happened in the middle of a continent. Before being drowned, he would be burnt or crushed. Let us reserve our compassion for the poor sailor, who congratulates himself upon having reached an hospitable coast, and suddenly sees his vessel scattered to the winds and waves by the violence of a submarine explosion. 286 THE BOTTOM OF THE SEA. CHANGES IN PKOGKESS AT THE BOTTOMS OF SEAS —THEIR UNIVERSALITY. 1. Extent of the movements of the Terrestrial Crust — Nature in cessautly at work — The gradual Cooling of the Earth a cause of its present form, owing to the crumpling and breaking of its Crust. Everything material is mutable : continuity of change is the great law of nature. From the subtlest gas which escapes our visual observation, to the solid rock, all is subject to movement and transformation. The smallest atom and the mightiest solar system alike obey the laws of gravitation, and move on in cycles of endless progression. The modifications which everything, small and great, in the pliysical world is undergoing may be more or less apparent, more or less rapid; but whether it be or be not. de- monstrable to the sense, it takes place all the same, so that we may truly say that all matter, however apparently dead, pulsates with life. Animals and plants are born, grow, and die. The elements which concur towards their formation and development are incessantly renewed. Having accom- ALL THINGS MUTABLE. 2£7 plished their part in the organisation to which they had accrued, they are rejected, and their place taken by others. At a given moment they are, so to say, shunted. off the track they had followed, and moved on a line to contract new alliances. To the being with whose existence they were identified succeeds another, totally different ; instead of the concentra- tion of force, there reigns for awhile anarchy ; and anarchy is followed by the rise of fresh organisations, destined in their turn to disappear. There is no organised being that is immutable, any more than a simple atom that is so. In like manner we learn from history that whole peoples, or national individualities, are born, grow, and die, like individual men, to be succeeded by others. Nay, even the species is no exception to the law of everlasting change. But at least, you will say, the solid rock is allowed to repose in quiet, and enjoy the privilege of im- mutability ? No ; its surface is exposed to the action of all manner of exterior influences, and eve every variation of temperature profoundly affects that apparently unchangeable mass. The truth is, our view of things is a very limited one. The in- finitely great escapes us as well as the infinitely little. Even a wheel moving with great rapidity seems as if it did not move. Again, an extremely 288 277^ BOTTOM OF THE SEA slow movement of the same wheel would not hp> observed. The air is composed of a great number of elements. Oxj^gen and nitrogen form the greater part of its composition. The vapour of water, carbonic acid gas, and every kind of emanation from the earth's surface, add themselves to the two first-named gases. Oxygen is absorbed by animals, and replaced by carbonic acid. The converse takes place in vegetation, and a like exchange of gases occurs in combustion. The vapour of water, raised by the action of the winds from the vast oceanic reservoirs, floats above us in the form of clouds, and is distributed over the surface of the earth in beneficent showers. But again the water finds its way back by means of rivers and floods to its original point of departure, to be again converted into vapour and recommence the cycle of its transformations. There is a compensating or balancing process continually going on among the numerous causes of change, which renders the composition of the air sensibly constant, and makes its every movement tend to uniformity. The cloud which obscures the summit of a moun- tain marks the locality of a very rapid movement of the air. This motion is caused by the contact of a hot and moist air with one much colder. But the wind bears APPARENT IMMOBI LIT Y. 289 the c'lo::(l auay, and it dissolves aj>aiii, or vanishes when the air is dry. The apparent immobility of a cioud on the top of a mountain is caused by its being constantly re-formed. Its variations are really inces- sant and rapid. They pass unobserved by us, and liiu«, fur a long- period together, mountain-clouds appear as if they had settled down immutable. Very slow changes, as we have remarked above, present the appearance of unchangeableness, no less than very rapid ones. The vault of heaven is thickly besprent with stars, the greater number of which we call " fixed," while a few, called " planets,'* constantly change their places. The fixed stars, while preserving the same relative position unchanged, seem, as a whole, to make a daily revolution round a point marked by the polar star, and the latter, or centre of rotation, does not at first sight appear to shift its position. A long and careful study of the heavens, however, has shown that this is not the case. The apparent revolution of the whole concave of stars is accounted for by th(. fact that the earth moves on its axis, as well as describes an orbit round the sun. But the stars are at such an enormous distance from us that the axis of our globe remains, practically, parallel to itself during the whole period of the earth's annual revo- lution, so that, Jit any given period of the year, the u 290 THE BOTTOM OF THE SEA. stars are seen in the same places as if the centre of the earth were a fixed position — that is to say, as if it always pointed to the same spot in the heavens. This constant parallelism of the earth's axis is, how- ever, only apparent. In reality, it shifts to the extent (taking the extreme limit) of 4°, its revolution describing a cone in about 20,000 years. If the stars are thus shifted from their apparently fixed position, their relative situation is at least con- stant, you will say? Careful observation, extended over many years, has shown the contrary. The whole solar system is moving, as if it were one com- pact and independent organisation, through space. Astronomers have demonstrated that it is approaching the constellation Hercules, but it would require ages of observation to detect any variation in the relative positions of the fixed stars. Such observation would demonstrate by an extraordinary effect of perspective, which it is no part of our present business to ex- plain, that their distance from Hercules is in- creasing. Every day the sun rises above the horizon, and TiCts at the opposite extremity of the heavens ; so the h(afc of the day succeeds constantly the cold of the night. Year after year the ice is melted by the soft breath of the spring ; year after year summer ripens the fruits of the earth. Year after year CLIMATE GRADUALLY CJIAyUJNir. 291 autumn, with its heats and tempests, despoils the trees of their beautiful verdure ; then, with the same regularity of succession, winter hangs her snowy garlands on the branches, and strikes with sudden paralysis the mountain torrent. The same succes- sion of phenomena appears to be continually repro- duced, with such modifications as would suggest a capricious and ill-regulated will. Notwithstanding that apparent regularity, within certain limits, the climate of the earth is undergoing a slow but con- stant variation. The debris of every kind found in the earth's crust affords demonstrative proof that the distribution of temperature on the surface of the globe has been very different at remote periods from what it is at present. The surface, beyond doubt, has been subject to numerous vicissitudes; but at least, you will say, the centre of the earth has re- mained unchangeably the same. This, however, cannot be the case; for, as the earth has grown gradually cooler, its crust has in- creased in thickness and solidity. The contraction towards the centre has been the cause of breakageb and crumplings in the earth's crust, and, consequentl), of the upheaval of mountains and continents, the sinking of the surface to form valleys, and, generally speaking, of such variations of the terrestrial land- scape as could only be produced through a long 292 THE BOTTOM OF THE SKA. succession of ages. The human race has not existed for a sufficiently long period to witness the grander catastrophes or changes of what, nevertheless, there are palpable traces remaining to attest the reality. We are the living witnesses, however, of changes whose average rapidity permits our senses to follow the phenomena, while our memory or our records enables us to compare with ease the different phases through which they pass. We observe that the sea changes its level day after day, as if it oscillated around a fixed point. We are witnesses to the silting- up of ports by the action of marine currents ; to the ravages of the sea when it hurls its waves against a rocky coast ; and to the growth of the polypier, which opposes an invincible rampart of stone against the assaults of the ocean, and builds up islands from the very bosom of the waters. We see the mountains crumble down under the action of atmospheric agen- cies ; the debris of continents washed down by rivers into the sea, to fill up its abysses ; the floating ice- chariots scattering the spoil of arctic lands over every part of their route ; marine currents drawing in their train whatever they encounter, and accumulating upon their borders immense deposits of vegetable and animal remains, as well as of sand and mud. We see the foraminiferae, those pigmies of creation. SOLWItlCATlON OF THE EARTH. 293 obstinately, and with immense labour, striving to build up every possible obstacle to navigation ; while volcanoes, like malignant demons, destroy the exist- ing basin of the ocean, or at least are incessantly active in modifying its level, or filling up its hollows with ashes and cinders. With our own eyes we are witnesses of these and innumerable other agencies of change ; and, knowing the vastness of their con- sequences, we judge, in regard to past effects, what causes have been in action from the results they have produced. For this reason, the exploration of the bottom of the sea is an excellent preparation to the study of the past history of our planet, and of its future pos- sibilities. The sea itself would not exist except for the fact that the earth was originally a fiery mass, the surface of which has become solidified, and in the process of cooling has allowed the aqueous vapours to condense. Originally extended with an even surface over the whole globe, the sea served everywhere as the menstruum of the first solid pre- cipitations. Thenceforth the crust of the earth grew in solidity and depth, both from the exterior and the interior — on the one side by sedimentation, on the other by solidification. The cooling process continued. The crust, too 294 THE BOTTOM OF THE SKA large for the kernel which it everywhere enveloped, caved in, and thus the first heaving-up of mountainous masses marked the end of a geologic period. Lands rose above the waters, and marine deposits no longer covered the entire globe. The constancy of the ocean temperature, owing to the near neighbourhood of igneous matters, rendered very feeble, or alto- gether prevented, the formation of marine currents. As the equilibrium gradually ceased to exist in the liquid mass, owing to the constant growth and the changes that were taking place in the earth's crust, ocean- currents came into being. The atmosphere was, in its turn, modified by con- tinual precipitations and despoiled of its vapour of wat^r, which went to elevate the level of the seas. This operation again brought into existence atmo- spheric currents. The crust of the earth still continmng to cool, fresh collapses would take place, and fresh wrinklings or foldings of the solid envelope already formed. New mountains arose from tlie bosom of the waters, new rendings of the soil gave free passage to the igneous matters in the interior, and hence the great extent to which volcanic matter is found spread over the surface. By this time living creatures had ap- peared, which at first were remarkable for the sim- plicity of their structure and for the capability of CHANGE OF THE SEASHORES. 295 the same species to dwell, at the same time, on any part of the earth. The currents of the atmosphere and the ocean were more and more decidedly and definitively established. The extent of dry land was continually increased by fresh elevations above the waters. Kivers and lakes were formed ; in addition to the hitherto ex- clusively marine deposits were those of the fresh waters and salt pools. Plants growing in marshes or on dry lands extended their species over new con- tinents. As time went on, the inequality of temperature at different points of the globe augmented ; the existing mountains increased in height; new ones were heaved up ; the fauna and the flora became more localised, and the marine and atmospheric currents approached insensibly to the condition in \\hich we find them. 2. The Shore — Its apparent fixity — Traces of the presence of the Ocean almost universal. Have we yet reached fixed conditions, so far as reo-ards the earth's surface ? Can we be certain that some fresh revolution of the globe will not destroy the edifices of which we are so proud, and wrap in a watery shroud the accumulated fruits of civilisation ? If we have indulged in any illusion, it is only neces- 296 THE BOTTOM OF TEE SEA. sary to study with care the phenomena by which W6 are surrounded to dispel it for ever. Continual change is going on in the basins of seas. These changes make, generally speaking, but slow progress, and are therefore difficult to follow ; but little by little they assume a character of the greatest importance. Sometimes, however, they are sudden, and accompanied by phenomena so terrible as to strike mankind with horror, and apparently to disturb the harmony of the universe. How shall we demonstrate the truth ot our state- ment, that the bed of the Ocean is constantly chang- ing? What we observe is that the sea rushes furiously against the shore, and throws its foam over the highest rocks. As the waves roll in, it would almost seem as if nothing could oppose a barrier to them : suddenly they are arrested, and the dreaded power expends itself by diffusion, as it were, in an inoffensive sheet of water. But another wave follows the first. A third presses on, and almost overleaps the former two. Nevertheless each succeeding column of the invading army is vanquished at the same point ; in a word, the sea has encountered its shore. Thus, day after day, the ocean seems to hurl defiance against the earth ; and if it retires, it is to renew the assault against the barriers which it seems resolved to break through, with redoubled strength. CIIAXGES STILL L\ FltOGRESS. 207 Twice every day it advances, and covers with its waters the vast extent of its coasts ; twice it retires, abandoning to men some of its spoils and treasures Kestrained by a powerful though invisible hand, it apparently yields to the obstacle which opposes its advance. Its movement is so regular that we can determine, for every point of our coasts, the exar^t times of high and low water. Thus regarded, the shore of the ocean would appear to be the very type of unchangeableness. The sea cannot pass it ; in our confidence we cultivate lands, build cities, construct ports and harbours, and throw out piers, as if we dared the sea to do its worst. If we would know how puny oar best efforts are, let us note the fact that marine shells, the fossil remains of fish, and other evidences of the presence of the ocean, are found on the highest mountains. This debris of former ages has been converted into stone, and now exists in gigantic masses. It is impossible to say how many ages may have elapsed since they were living beings : history and human tradition take no account of them. Are we to imagine that those remote ages were visited by the most frightful of all catastrophes, and that we, more privileged, are exempt from similar changes and their attendant dangers ? No ; the Supreme Intelligence which governs the universe 298 THE BOTTOM OF THE SEA. has regulated the working of its stupendous me- chanism. Everything occurs at the regulated time. Nothing is left to chance. The sea has once covered the whole earth. Geology affords the data by which we may determine its limits at successive epochs. But it is not necessary even to revert to remote geological periods in order to be convinced of the fact that land and sea have frequently changed their relative level. Progressive enlargement of the Straits of Gibraltar during the Historic Period — Columns of the ancient Temple of Hercules submerged — Descriptions left by Avienus, Pliny, and Pom- ponius — Mellaria, Carteia, and Belon submerged — Other examples of Cities and Islands covered by the Waters, and of Mountains violently separated from Continents. The Straits of Gibraltar is a conquest of the ocean. Dureau de la Malle quotes the measurements of old geographers, and they tend to show that it has been continually enlarged even down to our own times. Avienus quotes a measurement on the authority of Daemon d'Amphipolis. It is nearly three miles, or more accurately 4694 English yards. He cites a subsequent measurement of nearly four miles, or 6000 yards, made by the Athenian Euctemon. Scymnus of Ohio, in the year 143 B.C., found it measured nearly 24,000 yards, or about thirteen milos STBAITS OF GIBli ALTAR. 299 on the side of the Atlantic, wliile at the presnt time it is double that distance between Spartel and Tra- fiilgar. Turanius Gracilis, who was born on the shores of the strait 100 years B.C., gives the width from Mel- laria, in 8pain, to Cape Blanco, on the African side, as about foui -tind-a-half miles, or, more accurately. 7800 yards. Strabo estimates the greatest breadth at nearly seven miles, or about 12,000 yards. Pliny, who had been quaestor in Spain, and had visited the strait, gives about seven-and-a-half miles for the narrowest part, and about ten miles for the widest. Bishop Victor, about a.d. 500, found the distance about twelve miles ; the Spanish measurement at pre- sent is fourteen miles. These various estimates are good evidence that the strait has been gradually enlarged from remote times to the present. Besides this, Avienus relates that between Africa and Europe there were two wooded isles, on which were built a temple and altars in honour of Hercules. These were called the Pillars of Hercules. The same author mentions that the Car- thaginians were obliged to build flat-bottomed vessels to sail over the shallow water. Finally, he says, we know that Hannibal reports that there was a bottom- 300 THE BOTTOM OF THE SEA, less and boundless sea farther to the west — a proof that what he says about the Straits of Hercules may bi regarded as trustworthy. Pliny, who visited the straits, speaks of a low-lying island, covered with wild olives, situate in mid chan- nel, upon which was built the Temple of Hercules. Pomponius Mela, a Spaniard, to whom these parts i Jjectai ireadth ahomt 6iTniles— Greatest hreadth about 9 miles woo yds Fig, 58.— Straits of Gibraltar. 1. View and Section in the time of Pliny. 2. Section of the existing Charts. were familiar, pictures the strait as a channel broken by a number of small islands without names. In our day the largest ships sail freely over these waters. In 1748, on the occasion of a very low tide, the remains of the famous Temple of Hercules were dis- covered in the oceanic part of the strait, and some souvenirs of it were obtained for preservation. Jean Conduit, as related by Signer Ignacio Lopez de SUBMERGED CITIES. 301 Ayla,in his " History oi' Gibraltar," assures us that the sea covers the greater part of the land on which stood the ancient city of Mellaria. Even in the Bay of Gibraltar the sea has engulfed a part of Carteia, or Algesiras. Three leagues to the west of Tarifa, the city of Belon occupied the shore of the strait. It is now engulfed, and we find traces of its existence beneath the waves. Colonel James, in his " History of the Straits of Hercules," mentions that during an earthquake, some ages ago, the Isle of Gales disappeared, together with the small islands opposite the city of Bactes, near Tarifa, and a rock named La Perle, which was once an island, and is now covered with more than twelve feet of water at low-tide. The same author speaks of violent shocks of earthquake, which, in the year 246 B.C., overthrew the last remaining part of the Isle of Cadiz, and left it completely covered by the sea. The earthquake of 1755, which destroyed the city of Lisbon, and was felt far and wide, was not, says Colonel James, to be compared for the violence of its effects with that which engulfed Cales, which was of many leagues in extent. Nevertheless, it was plainly I'elt at Gibraltar, wiiere Colonel James himself was an observer of the phenomenon. On the morning of the 1st of November, 1755, a 302 THE BOTTOM OF TEE SEA. shock was felt which lasted half a minute. It com- menced by a trembling of the earth, then a violent sliock succeeded, which was followed by a trembling similar to that with which the earthquake commenced, and which gradually diminished. The sea rose more than three yards above its ordinary level, and then sank, leaving dry upon the shore many fish, and all that it had at first engulfed. We may add to the list of cities that have been lost those of Helice and Bura, in Achaia, which were submerged in the year 368 B.C. The greater part of Lycadia w^as also covered by the waters. Strabo, in his Egyptian voyage, relates that he saw Mount Casius, which had been suddenly sepa- rated from the continent and become an island, which it was necessary to sail round to reach Phoenicia. Sorca, one of the Moluccas, was swallowed up by the sea during an earthquake in 1693. At Java a mountain, three leagues in circum- ference, disappeared suddenly in 1772. It is on record that a space of about sixty leagues, in the province of Chan-tsy, in China, was completely covered with water in a few days, in 1566. St. Lawrence once joined the American continent, out is now separated from it by an arm of the sea, some hundreds of yards broad. One of the most disastrous eruptions of the sea on DISASTERS IN ZEA LAM). 303 record is that wliich, in l-Ul], submerged more than two Imndred cities of FriesUiiid and Zealand. For a long time after this catastrophe, the summits of the Fig. 59, — Irruption of the Sea in Zealand. towns and the points of the steeples could be seen standing above the surface of the sea. • We might multiply these examples of the fact that the bottom of the sea is continually changing. Here 304 THE BOTTOM OF THE SEA. cities, nay entire continents, are covered by tlie waters : there, on the other liand, the land has been known to rise, as in the case of the island of Julia, and in that of the Azores, and the Archipelago of Santorin. The port of Aigues Mortes has now three leagues of shore. The ruined Temple of Serapis, at Pozzuoli, was for a long time engulfed ; it is now uncovered again. In the north of Sweden the sea appears to be retiring, whilst it slowly invades the south of that country, and at no very distant period it was the cause of great destruction by its inroads in Pomerania. 4. The Quantity of Water which covers the Earth is sensibly con- stant — An Elevation in one point, is balanced by a corre- sponding Subsidence in another — Aristotle's opinion about the Greek tradition of the Deluge — Tlie Earth will become dryer and colder. If the sea retires from a given place, another be comes submerged. We are, therefore, led to con* elude that the water area varies but little over the whole of the earth's surface, but that the bed in which it rests is ceaselessly modified. Such, moreover, was Aristotle's opinion. He be- lieved that the apparent changes in the level of the sea in any given spo^ could not be explained by the supposition that the seas were drying up, as certain philosophers of his time had imagined. In the OPINION OF AlillSTOTLi:. 305 svords of this illustrious sauan : ' Only those ol narrow news and small experienc(3 attribute these partial changes to an overthrowing of the whole globe. When, in support of their views, they bring forward the drying-up of seas, and th(^ existence of dry land where it formerly was not, they give authentic facts, from which, however, they deduce false conclusions. It is true that certain spots heretofore covered with water now form a portion of the continent, but the contrary is also the case, and any one who studiously examines the facts would find that the sea had invaded and submerged several parts. Such appears to be the explanation of Deucalion's flood, the ravages of which were more especially felt in Greece, and which among other provinces was most terribly felt in ancient Helas, a country extending from Do lona to the Achelous. This river then changed its course several times. The province was at that time inhabited by the Selles, and by the people nanjed Greeks, now called Hellenes." Certain coasts of the same sea will, in the same time, show but little variation. The Strait of Messina, moi"e especially on the Sicilian side, re- ceives quantities of sand; but it has relatively suffered such slight changes, that the same race have in- habited it since the time of Homer. In reading the descriptions given of this place by Homer, Polybius, X 306 TEE BOTTOM OF THE SEA. aud Spallanzani, it is surprising to find that autliors living in times so far apart give similar details respecting the inhabitants in this arm of the sea.* Now we have seen that marine animals sometimes emigrate, and leave their haunts to otlier species, if the depth changes notably. Swordiish are now still caught in the manner described by Polybius. Sometimes the movements of the terrestrial crust are limited to a very small range of country — some- times they embrace a very large extent. They are nearly always compensated by inverse movements, produced at more or less distant points. The gradual * Polybius wrote, two thousand years ago : " The swordfish, sea- dogs, and other cetaceous animals, become singularly fat every year by living on the tunny-fish, which visit the coast of Italy in shoals^ and which their enemies watch for iii the straits. In fishing two men are attached to each boat — one sculling, and the other standing at the prow armed with a spear. The various boats have a common scout, in an elevated situation, who signalises the approach of the swordfish, for the fish swims with half his body out of tlie water. When it approaches the boat the spearman strikes it with his spear, the licad of which carries a barb, loosely fixed, so that it can be easily detached whtn the spearman withdraws the handle. To tlie iron head of the lance is fastened a long cord, which is let out to the wounded fish, until by his continued struggles to escape he shall have lost all his strength. Then they haul it ashore, or, if not, take it on board their boat. If the spear-handle fall into the sea, it is not necessarily lost ; it is made of oak and spruce, in such a manner that the oak sinking on account of its greater weight permits the spruce to project above the surface of the water, so that the fisherman may easily see and regain it. Sometimes it happens t at the rower id wounded, the swortlfish being armed with a long sword, and being as furio-.is and impe'.uous as a boar." FUTURE OF THE EARTU. 307 cooling of our planet causes tlie thin crust already formed, by unequal contraction, to pucker up. The sea occupies the cavities — the prominences alone appear above the waters. Water tends to combine more and more with the rocks. A time will probably come when the earth will be too cold for water to exist in the liquid state. It is to be understood, in fact, that the quantity of N\ ater whicli bathes our planet continually diminishes ; but this diminution is so slow, that thousands of years are not sufficient to make it evident. 808 THE BOTTOM OF THE SEA. SUDDEN MOVEMENTS OF THE SUBMARINE SOIL. 1. Earthquakes modify the Bed of the Ocean — Submarine Volcanoes. The bottom of the sea, as well as the surface on which we live, is subject to modifications by the action of earthquakes. They are, generally, accom- panied by submarine volcanoes, which also alter the sea-berl, and cause a displacement of the waters. It is observable, in fact, that volcanoes never display their whole enerofv except in the neighbourhood of seas or large sheets of water. The existence of sub- marine volcanoes need not then excite astonishment ; it is probable, indeed, that their number is very great, and it is reasonable to attribute to the action of submariDO eruptions of which we have no know- ledge, the seismical phenomena that have been ac- companied by no visible volcanic disturbances. At the commencement of its activity, subma- rine volcanic action is sometimes signalised by a peculiar agiiaticn of tbe sea, where the depth is at >J>' LBMARINE VO L CANOES. U'J all considerable. It" the depth be sliglit, or the activity of the volcano very great, the water bubbles ; a column of smoke rises above the level of the sea ; flames, scoriae, or incandescent stones demon- strate the presence of a volcano. The sea changes colour to a greater or less extent, and becomes Avarm. Ships receive a shock as if they had struck a rock ; indeed, in some cases the concussion is so violent that vessels have lost their masts. Volcanic products of every kind, liowevor, ac- cumulate at the bottom of the sea, covering every F«?-^f Fig, 60. — Eruption of a Submarine Volcano. living thing ; streams of lava, masses of scoriae, and roclcs, contribute to an elevation of the soil Avhich must eventually raise it to the light of day. Such is often the origin of volcanic islands. Submarine earthquakes disturb the sea through- out its whole depth, causing the terrible waves of 310 THE BOTTOM OF THE SEA which we liave spoken in a previous chapter. Tlic facts we are about to relate will exhilut the great influence exerted by subterranean fires over the sub- marine regions o'the who'e globe. 2. Greek Archipelago — Delos and Rhodes upheaved from th"^ Bottom of the Sea — Successive additions to the Archipelago of Sautorin. The existence of submarine volcanoes has long been known. Several are to be found in. Greece. The islands which have appeared from time to time, as if by encliantment, have owed their birth to vol- canic causes. Ancient writers niake mention of certain phenomena of this kind ; but their state- ments, being founded for the most part on inexact information, or on more or less uncertain traditions, can be of little utility from a scientific or even his- torical point of view. "The celebrated islands of Delos and Khodes," says Pliny (Liv. II. chaps, xviii. and xix.), " have, from all accounts, risen from the waters : moreover, smaller ones have been seen to appear — such as Anapte, beyond Melos; Nea, or Nova Insula, be- tween Lemnos and the Hellespont ; Alone, between Lesbos and Theos; Thera and Therasia, amongst the Cyclades, in the fourth year of the 135th Olym- piad ; Hiera, or Automate, situated bet\veen th.e two NEW ISLAXns FORM EI). :M1 p^ece(ling■, and formed loO years subsequently. In our time, 110 years later tJian the above, during the consulate of M. Julius Silaiins and L. Balbus (year 19 A.D.) appeared Thia." Many other ancient authors — amoni^ the rest Justin, Cassiodorus, Dion Cassius, Plutarch, Seneca, and Strabo — give very circumstantial details of the successive birth and growth of some of these islands by their elevation out of the sea. But the oiigin of some of them is surrounded with purely fabu- lous circumstances, and we are obliged to reject nearly all the ancient narrative:^ as being but little worthy of belief. Volcanic phenomena were not seriously studied, or even carefully observeil, until modern times. One of the most celebrated islands of the Grecian Archipelago is Tliera, subsequently named Sante- Irene, and later, Santorin.* Half a league from this island now exists Apronysi, the ancient Therasia. It appeared for the first time in 236 B.C. (the fourth year of the 135th Olympiad, according to Pliny, cited above). Automate appeared 130 years after (106 B.C.), and was named Hiera in consequence of the worship * Santorin is an immense craterifonu mountain, some thirty-six miles in circumference. It may be accurately described ns a furn ;ce of incessant volcanic activity, some part of it being almost con- stantly in eruption. — Tr. 312 TEE BOTTOM OF THE SEA. of Vulcan there e>!tablished. Thia (4 B.C.) rose at the distance of about oOO yards from Hiera. The details given by the ancient geographers, therefore, agree with each other. Violent eruptions of cinders,' rocks, and lava, in a state of ignition, filled the arm of the sea which separated Thia from Hiera in the year 726 of our era. Similar phenomena occurred in 1427, as is at- tested by a marble monument erected in Santorin, near Fort Scauro. A new island, designated Nea- Kameni {New Burnt-island), appeared in 1570, at the termination of a sixth eruption. Hiera was then called Paloe-Kameni, which signifies Old Burnt- island. We owe to Father Kircher the details of an eruption which, in 1650, threw these coasts into trouble during a whole year. It was accompanied by showers of cinders and whirlwinds of flame, which were seen to issue from the sea. The quantity of cinders thrown out was so considerable, that ^Smyrna and Constantinople w^ere much inconvenienced. A new island was thrown up in 1707. Mens. J. Girardin describes this phenomenon in the following words : " On the 23rd of May, 1707, at sunrise, a floating rock was seen at sea about a league from the shore of Santorin. Some sailors took it for a ship NEW ISLAND NEAR SANTORIN. 313 about to break up, aud approaclied it with a vie\A to pillage. Arrived near, and seeing what it was, they had the courage to descend ; they brought back some pumice-stone and a few oysters whicli were at- taclied to it. The rock was probably a large mass of pumice, that the agitation of the earth, which occurred a little time prcA'iously, had detached from the bottom of the sea. After a few days it became fixed, and thus formed a little island, which auomented in size from day to day. On the ]4th of June it was some 800 yards in circumference, and about twenty-four feet in height ; in shape it was roundish, and formed of a white light earth. At this period the sea began to be disturbed, and the heat near the island was so great as to prevent access to it ; a strong odour of sulphur also spread around. On the lO'th of July there appeared in close proximity to it seventeen or eighteen black rocks ; on the 18th, a dense smoke was emitted by it for the first time, and subterranean rumblings were heard. On the 19th, fire began to be visible, and its intensity gradually augmented. At night-time the island had the ap- pearance of a number of furnaces vomiting flames. Its volume increased, and the iumes became insup- portable at Santorin. The sea was now violently agitated, an 1 dead fish were thrown on the shore ; the subterranean noises resembled discliarges of 314 THE BOTTOM OF THE SEA. artillery ; the fire made new openings, w hence issued showers of ignited cinders and stones, which some- times fell at a distance of two leagues. This state of things lasted a whole year. In 1767, a new eruption took place between Nea-Kameni and Paloe-Kameni ; it recommenced in the month of June, and after working ten or twelve days, a new island rose up in the neighbourhood of Nea-Kameni. During four months, a series of terrible phenomena occurred ; considerable portions of the island were swallowed up, but others were formed ; at last a second island ap- peared, and it united with the first in June. It was named the Black Island, on account of the colour of its soil. The subterranean disturbance continued until the end of the following year; and on the 15th of April, there occurred an eruption of large ignited stones, which fell two miles off." The eruptions and upheavings from the bottom of the sea continued long after. The Aeademie des Sciences sent M. Fouqud to study on the spot the manner in which this remarkable archipelago became developed. M. Fouque perfectly distinguished the two processes simultaneously working towards the produc- tion of new lands — the raising of the ground, and the increase of the raised spots by the deposit of lava, scoriae, and rocks, which were cast out from the boiling cavern. The bottom of the sea is, as we have seen, gei:erally THE AZORES VOLCAS IC. 815 colder than the surface, If, therefore, rocks situated at a great depth are brought rapidly to the surface, they will not have time to acquire warmth in rising, and will therefore cool the surrounding waters to a certain distance. The lava and stones tlirown out by the volcano will, on the contrary, heat the water sometimes almost to boiling. The elevation of the island of Julia, to the west of Sicily, was accompanied by phenomena similar to the above. 3. The Azores — Appearance and Disappearance of Islands subse- quent to Earthquakes — The ephemeral Island Sabrina. The Azores are entirely volcanic, and we there find the same remarkable phenomena occurring that we have alreafly noticed in the Grecian Archipelago. Evidence of the existence of a submarine volcano, near St. Michael, was given by four eruptions in less than 200 years. One of them began on the 11th of June, 1638, during an earthquake. Flames and smoke were thrown out by the agitated sea near St. Michael ; earth and rocks were projected to a great height, and, again falling into the sea, at last ac- cumulated sufficiently to form an island ten kilo- metres in extent, and nearly 400 feet high. Like Julia, the island soon disappeared. Another earthquake occurred suddenly on the 31st 316 THE BOTTOM OF THE SEA. of December, 1719, and an island was formed between Terceira and St. Michael. At first it was of sufficient elevation to be seen seven or eight leagues out at sea ; Fig. 61. — Submarine Eruption at the Azores. it vomited incessantly a thick column of smoke, cin- ders, and pumice ; a stream of molten lava flowed down its sides, and the sea became very hot in its neighbourhood. The height of the island diminished rapidly ; after existing two years, in 1 722 it had THE NEW li^LAXD SABl^iyA. 317 sunk to the level of the sea. It (Hsappeared on the 17th of November, 1623. Violent earthquakes disturbed the neighbourliood of St. Michael during the months of July and August, 1810. Shortly after (January 31st, 1811) the earth split on the eastern side of the island, near the village of Ginetas, a league and a half from the seashore. While the sea boiled violently, an enormous quantity of water and smoke, mixed with earth and cindeis, was tlirown into the air. Stones were thrown to a height of 2000 feet. The eruption lasted eight days ; a' bank of pumice was then visible, against which the waves dashed on a spot where the water was previously not much less than 500 feet deep. An island one or two kilometres in circumference, and about 300 feet in height, was the result of a new submarine eruption on the 15th of June in the same year. Captain Tillard, commanding the Sabrina, visited and took possession of it in the name of the English Government. He gave it the name of his vessel. Little by little the island sank, and towards the end of February, 1822, a little vapour, floating over the surface of the sea, was the only remaining trace of its existence. Porto de Itheo, a vast hollow ci-ater in which ships found a resting-place, as well as the island of Corvo, are of similar origin. 318 THE BOTTOM OF THE SEA. During a great eartliquake which, in 1757, de stroyed one-seventh (1500 persons) of the population of the island of St. George, eighteen islets sud- denly appeared about 600 yards from the shore. Their fate was similar to that of Sabrina. 4. Submarine Volcano in the Middle of the Atlantic. One of the most remarkable of submarine vol- canoes exists in the mi Idle of the Atlantic Ocean. M. Daussy had already pointed out a region, situated about 24° 42' W. longitude and 0° 50' S. latitude, as interesting on account of volcanic phenomena. We reproduce a list given by M. Yezian of incidents observed on this spot, since the middle of the last century, by a large number of sailors : — 1747. The ship Prince, bound for the Indies ; two shocks, as though the vessel had touched ground. 1754. The ship Silhouette ; extraordinary shock. 1758. Le Fidele ; shock. 1761. Le Vaillant ; an island of sand observed. 1771. The frigate Facifique; very violent shock, sea much agi- tated. 1806. M. de Krusenstern saw a volume of smoke rising, twice repeated, to a great height. 1816. The Triton ; a rock tiiree miles long and one mile wide, 26 fathoms of water ; bottom, brown sand. 1831. L'Aigle; calm sea, shock, rumbling sound beneath the water. 1832. La Seine; shocks. 1835. Ija Couronne ; scraped tlie bottom with her keel ; sounded afterward-, 35 fathoms. V()LCA\(J JN TUI-: ATLASTIC. S19 183G. Le Philanthrope ; shocks which Instcd three iniimtLs, and which were also felt two miles olT by another vessel 18HG. Some voleanic einders, collected near this i)oiut whilst ti.e earth was in violent agitat on, were forwarded to Calcutta. 1856. Regiiia Cadi; rumbling sound as of a distant ^torm ; after- wards severe shocks, accomi)aided by a noise similar to that produceil by striking several sheets of metal together. The helmsman was incapable of luanagiug the tiller, which was dragged from his hands. 1856. On the tame day and at the same hour — i.e., on the 30th of December, at 4 o'clock in the morning — the ship Godavery rvceived a severe shock at a slight distance from the Rerjina Cadi. 1861. February 20. Submarine earthquake felt on board the Felicie, which lasted a minute, and was preceded by a noise coming from the westward. 5. Submarine Eruptions near Kamtschatka — Iceland — Ignited Sea ; appearance of an Island near Reikianess— Kise of a Fiery Island I'rom the Ocean, near the Aleutian Isles. Occurrences similar to the above have often been observed near Kamtschatka, and in the latitudes of Hussian America. For example, an eruption occurred on the 10th of May, 1814, when an island rose above the water, vomiting bitumen through many fissures. Captain Kotzebue was eyewitness to the birth of f*n island near Ounimack, in tlie Aleutian Archi- pelago. An account of the circumstances will be found in the narrative of his voyage. On the 7th of May, 1796, M. Krinckhoif, agent of the Russian American Company, was at the north- west point of Ounimack ; a tempest, which blew from 320 THE BOTTOM OF THE SEA. the iiortii-west quarter, prevented him from seeing anything out at sea. On the 8th, the weather cleared, when he observed, at some miles from the shore, a column of smoke or mist rising from the sea, and as evening approached he saw something black upheaved above the smoke. During tlie night lire Fig. 62. — Rise of a new Island near Ouuimack. was emitted at the same place, and with such intensity, that at a distance of ten miles objects were perfectly distinguishable. Then a trembling of the earth, ac- companied by a frightful noise, which was echoed ICELASD. 821 from the mountains of the south, sliook tlie entire soil. Tlie nascent island belelied forth stones, wliieh fell even upon Ounimack. The earthquake ceas<'rl at sunrise, the fire diminished, and the new island appeared plainly visible, conical in sliape, and of a black colour. A month later, M. Krinckhoff saw it again. The island was higher than before, and during all this time it had not ceased to vomit fire. Aiterwards it appeared to increase in circumference and height, but the fire continued to diminish. Generally it emitted only vapour and smoke, and at the end of four years this phenomenon ceased also. When, about eight years subsequently, the island was visited by a company of trappers, the surrounding water was found to be of a very high temperature, and the soil so hot in many places that it was impossible to walk on it. Its circumference, which had gone on augmenting, was estimated at about two-and-a-half miles, and its height at about 350 feet. The bottom of the sea was strewn with stones even to a distance of three miles. The hottest part of the soil was from about the middle of the height to the summit, and the vapour which ascended from the crater was found to be of an agreeable odour. Iceland is a very furnace of volcanic activity, and we observe in its nf^ighbourhood phenomena of el eva- y 322 THE BOTTOM OF THE SEA. tion analagoiis to the instances we have already cited Mackenzie relates that, in the year 1780, he obsers^ed on the western coast of the island, at the distance of ten leagues from Keikianess, flames rising from the sea daring many months. Afterwards a little island made its appearance. For some time this island vomited flames and stones, and then disappeared again. Immediately afterwards the Skaptaa lokull, a neighbouring volcano, broke out in eruption. 6. The Bottom of tlie Sea feels the counterblow of teiTestrial Volcanic Phenomena. Terrestrial volcanoes and earthquakes are nearly always re-echoed, so to speak, from the bottom of the sea. Ships experience a shock as if they had passed over a centre of volcanic activity. Cracatoa, an island in the Indian Ocean, was de- stroyed in 1680 by an earthquake. Vessels at sea felt the shock. Gounung-Api, or Gounapi, a volcano in the Mo- lucca group of islands, burst into eruption on the 22nd of November, 1694. Its summit vomited flames witli a great noise. The bottom of the sea was, at the same time, heaved up to the level of the soil of the island, and flames ascended from the waters. In 1820, in a bay situated to the west of Gounapi, ERUPTION OF TOMUUIIO. 323 and where at other times sixty liitlioms were suiaided, a promontory was formed, which increased in extent until it filled np the bay. It is composed of gigantic blocks of basalt highly calcined. The phenomenon was attended with so little noise that the inhabitants Fig. 63.— Eruption of Tomboro in 1821. of the Banda (or Nutmeg) Islands were unaware of the occurrence until it W7\s perfectly accomplished. Tiic upheaval was slow, accompanied by an extiaordinaiy rise of temperature in the water, which butibled up in the I ay. a24 THE BOTTOM OF THE SEA. In the island of Bima, ur Sumbawa, there is a very active volcano, named the Tomboro. In 1821 such a movement of the sea occurred here, that the island was partly submerged, and vessels at anchor in the port vvere thrown to a great distance on the shore. Many were landed even on the roofs of the houses. Tomboro itself remained calm during the time, but a voh.'anic mountain to the north-east of it threw up stones and cinders in the midst of a torrent of vapours. The earthquake was felt in the neighbouring isles, at Celebes, aud even at Macassar, where the same de- vastation occurred as at Bima. These two places are nevertheless separated by an arm of the sea 100 leaiiues broad. 7. Products of Submarine Volcanoes — How they differ from the products of Subaerial Yoicanoes. A very close analogy has beea observed between the products of all the volcanoes on the earth's sur- face. Submarine volcanoes are no exception to the general rule. One and the same cause produces all these phenomena. The nature of the medium into which they eject their gas and igneous matter can alone occasion any difference in the character of the eruption. Suijinarine lava-streams may be expected to cover SUBMARINE LAVA. 82.5 a grvai extent, oi" the ocetiu-bed, according to the o})inion of Mr. Poulett Scrope, wlio has expressed him- self to the lollowing effect in his work on " Geology and the Extinct Volcanoes of Central France." " We ought to observe," he says, " that lava-streams at the bottom of the sea must have a greater breadth, com- pared with their thickness, than those which are cooled under atmospheric pressure, and that this lateral ex- tension is proportioned to the depth of the water." It ought also to be observed that lava-streams which have cooled at great depths under the water present little scoriae. This, in fact, has been observed in the old volcanic rocks of submarine origin. This, however, may be caused by the influence of ocean- currents, or other movements of the water." Some knowledge of the peculiar action of submarine volcanoes might be acquired by investigating their products, which may be brought to light by the sub- sequent elevation of the ocean-bed above the level of the sea. Examples of this are frequent in the coral isles of the Pacific. The basaltic columns of the south and north coasts of Ireland, of the Faroe Isles, of the north-east of Teneriffe, and numerous other localities, tend to demonstrate that the phenomena displayed by lava, when it is ejected beneath the sea, are very nearly similar to what occurs on the solid earth. I'he princijujl differences seeni to be: 326 THbJ BOTTOM OF THE SEA. 1. That the lava cools moi'e imiformly, and exteiiJs lurther upon a plane surface. 2. That a submaiine volcano ejects a less quantity of conglomerate, or of fragmentary matter, than a subaerial one, or that its igneous product extends further, and stratifies in thinner sheets of con- temporary lava, than is the case with tlmt of other volcanoes. Jf these opinions be correct, the regions where we find immense formations, sometimes slightly in- clined, of traprock and basalt, to which some coun- tries are indebted for their picturesque aspect, have been at some distant period submerged, and exposed to the action of a submarine volcano, which has covered them with its products. In such cases, when the volcano is in repose, it is obvious that submarine deposits of every kind — including animals and plants, if the depth be not too great — will be found, superimposed upon the lava. Accordingly, when the ocean-bed is upheaved to the light of day, we find a sheet of basalt between two beds formed of the debris of marine animals. lu Iceland we find subaerial volcanoes side by side with others of submarine origin, the latter having been upheaved to the light of day long after their activity had ceased. The first are the Jokiils, MAiniTius. ?.'n high mountains whicli {ibound in the island. 'I'Ik^ north and south of Iceland present an aspect tho- roughly characteristic of these facts. We there find immense phiteaux, whose submarine origin is plainly indicated by alternate beds of basalt and basaltic conglomerate. The Isle of France (Mauritius) has all the cha- racters of a submarine volcanic formation, which has been elevated en masse subsequently to the cessation of the eruptions. Bourbon, the near neighbour of Mauritius, presents, on the contrary, the appear- ance of the ordinary volcano, formed by the repeated coolings of lava-streams flowing from two or three sources constantly above the level of the sea, and one of which is in incessant activity. Allowing, however, that the remarks of Mr. Poulett Scrope are well-'bunded, it must be owned that they are subject to numerous exceptions. The remark- able investigatio;;s of M. S inte-Claire Deville have, in fact, demonstrated tliat the nature of volcanic pro- ducts vjjries ac< ording to the length of time that the volcano has been in activity. It would lead us too inY from our special subject to discuss this interesting question, but we may indicate in a very few words one of the many results obtained by M. Deville. A volcano seems to have its period of youth an I its pi rio ' of old age. During the first period, lavas are .^28 THE BOTTOM OF THE SEA, ejected; duringthe second, basalts. If a volcano whicii vomits lava is in repose, we may always expect a new eruption. When, however, the lava is succeeded by basalt, we may be equally sure the volcano is on the eve of extinction. We must, therefore, be careful not to pronounce too absolutely as to the marine origin of volcanic products from their nature and aspect. 8. Bottom of the Sea brought to light in consequence of tlie Eruption of Submarine Volcanoes. If a mountain belching fire is lifted above the level of the sea by the action of some subterranean fire, it carries with it the marine formations to which it had served as a support. The same expansive force acting upon a larger scale, and not limiting its effects to the elevation of the mountain, will raise to the light of day a more extended region of the submarine world, with allthelayersof(^e5m, sometimes of very ancient formation, which cover it. This is what we observe to have happened in Mauritius and two neighbouring islands. The con- figuration of the northern part of Mauritius is that of a level plane, formed of a recent calcareous rock, com- posed of polypi analogous to the coral. It covers the volcanic rocks whicli elsewhere form the summits of the island. The superposition of madrepores and coiiAL hi:i:j':^ of the FACIFIC. :^2i> (;oials upon volcanic [)r()diicts, is an evident proof that their formation was subsequent to the emission of the lava upon which they had planted themselves when it was sufficiently cool. But polyps live under water. The lava therefore, in this instance, must have been of submarine origin ; the ocean-bed thus formed was long afterwards upheaved to the light of day. By far the greater part of the surface of a group of islands situated a little to the east of Java, is com- posed of beds of coral, in all respects similar to those which are still in formation, and which constitute the well-known dangerous reefs of the Pacific. It is obvious that, in this instance also, the coral polypi had taken up their abode on the cooled lava, and that the whole mass Wiis afterwards elevated alove the ocean, as in the case of Mauritius. In the island of Pulo Nyas, to the westward of Sumatra, beds of coral, similar to those of the neigh- bouring seas, have been raised to a height of many hundreds of yards. In the earthquake w^hich, in 1820, destroyed a part of Acapulco (as described in a previous chapter), the level of the sea remained during t\vo hours about 30 feet below its ordinary level, in conse- quence of the land having been raised to that extent. On the other hand, we remark a permanent 330 THE BOTTOM OF THE SEA. elevation of the shore at Chili, to the extent of two or three yards, in consequence of an earthquake which destroyed Taliuano in the Bay of Conception. It would be possible to multiply, very greatly, examples of these upheavals of the submarine soil. We have only to recall the frequent formation of new islands, alluded to in a previous chapter. The sudden changes which actually take place in the basins of seas are, in most instances, easy to verify. Often they are the cause of terrible catas- trophes, which affect whole populations, and leave an indelible impression on the memories of those who witnessed or suffered by them. a^i GRADUAT. CHANGES OF THE BOTTOM OF THE SEA. 1. How the gradual change of the Sea-bottom can be demonstrated — Modifications which the Map of Europe would suffer by a gradual subsidence of Thirty Feet in a century — Paris sub- merged — Europe as it would be were the Level of the Sea raised 500 feet — Toulouse and Vienna as Seaports. We have studied the more sudden shocks to which the earth's crust may be subjected. Incessant move- ments of a more gradual kind, which to be demon- strated must be studied during several generations, also influence it, embracing vast regions, and in- fluencing equally the bottom of the sea and the highest mountains. Under the influence of such slow, almost insensible, changes of the eai^th's crust — countries, at one time flourishing, have disappeared, and others have risen in their stead. So long as our study is confined to the sea, or to the interior of continents, we may look in vain lor evidence of such changes ; but if we visit the shores, we may find abundant proof that the ocean is either gradually retreating from, or slowly gaining on, the land. If the sea be apparently retreating, it is a 332 THE BOTTOM OF THE SEA. proof that the land, at that particular spot, is rising. If the sea be gaining on the land, we may be assured that the soil is sinking. On any coast terminated abruptly by a high cliff, we may perceive above high water-mark an easily distinguishable line. The waves disintegrate the rocks. They are aided in their work by animals, of which we have spoken on a previous page. The pholades and other stone-borers are impelled by their instincts to select for their abode the line of demarcation between the two elements, where the air and water may be said to strive in perpetual con- flict. These boring animals cannot lemain con- tinually submerged, but the presence of water is in- dispensable to their existence. The cliffs against which the waves dash are better suited to their existence than any other situation. Wherever we find that these animals have established their abode, there must have been at one time the seashore. If the sea gains on the land, the colonies of pholades advance higher with the waves ; if the sea retires before a rising continent, the pholades follow in its retreat. Where the waves die away on a beach only slightly inclined, a coast-line is formed of rounded pebbles and rubbish, across which the waves only pass during great storms. This line defines the liliSL' AM> FALL OF COAiSTH. 333 boundaries of the ocean. If tlie land be rising, this coast-line will appear to recede from the water, while a fresh one will be continually in course of formation by the retiring ocean. The encroachment or retreat of the sea, easily proved in such a case, is much less obvious on a rocky or very steep coast. Where the ground is nearly horizontal, a slight rise in the level of the sea Nv'ill cause the inundation of a great extent of country. The encroachment of the sea on an abrupt coast is, on the contrary, insensible; and a number of ob- servations, often repeated at considerable intervals, is necessary to obtain a definite idea of the phe- nomena. • If to this difficulty in making observations we add the complication caused by the ebb-and-flow of the tide, we may easily comprehend why so many years have been necessary to demonstrate and accurately to measure the sinking of the land on the coast of Sweden. When the earth is thrown up arounl us with a great noise, when crevices are produced in an instant, and the solid ground trembles and quakes beneath our feet, we can have no difficulty in remarking the facts. But although, after an earthquake or other perturbation of that nature, the country remains either raised or lowered several yards, the inhabi- 334 THE BOTTOM OF THE SEA. tants of the interior of a continent would not be in the least aware of it, nor wogld they be more sensible of a slow and continnons rise or fall in the level. The seaside inhabitants would, however, recognise it by the obvious change in the level of the sea — the measure of its apparent rise or fall being equal to the actual rise or fall of the soil. If Europe, sinking uniformly, laid itself open to the invasion of the sea, what would not be the modi- fication of its map after a comparatively short time ? Suppose the whole continent to sink at the rate of some ten yards in a century: at the end of fifty centuries, or 5000 years, the level of the sea would have risen some 500 yard^ — a result which would cause many rich plains and opulent cities to be engulfed. Paris, with her lofty monuments and her hills, would have disappeared long since ; a forest of marine plants would have covered this beautiful city, and marine animals would have disported them- selves in her streets. The sands and other deposits with which the sea covers its bed, as with a vast curtain, would soon cover up the present scene of such advanced civilisation. Paris would disappear l)eneath the sea, as Nineveh beneath the sands of the desert. But the change in the level of the sea need not be so great for the map of Europe to become EUROPE SUBMERGED. 337 unrecog^nisable. The map at the commencement of this cliapter represents the appearance which would be presented by Europe, supposing the level of the sea were to rise some 500 feet. Its land-connection with the Asiatic continent would then be broken ; it would become an archipelago traversed b}^ large arms of the sea. The valleys of the Vistula and the Dnieper would become vast sheets of water. An imuKiise gulf would flow up the ancient valley of the Danube ; a narrow channel would separate it from an interior sea corresponding to a large part of Hungary. Den- mark, the low-lying plains of Germany and of the Netherlands, would be replaced by the ocean. England and France would be very much cut up. In the latter would be found three large gulfs, corre- sponding to the pr. sent courses of the Seine, the Loire, and the Garonne ; fishing boats m ould anchor over Bordeaux and Orleans, and make land at Toulouse. A narrow isthmus would unite France with Spain in the neighbourhood of Castelnaudary, and the rich wine-growing countries of central France would become transformed into submarine prairies. The plain of the Po and the valley of the Ebio would make way for deep gulfs ; though, in general, the northern shores of the Mediterranean would suffer but little change. This would not be the case with the low plains which constitute Egypt and Cyre- z 338 THE BOTTOM OF THE SEA. uaica. They would become one vast sea, bounded by the mountains of Algeria, Morocco, and Abyssinia. The climate of this part of the world would in conse- quence be much changed. Immense sheets of water would cover the saline steppes of Kussia ; they would extend into Turkestan, as far as the Siberian mountains and the table-land of Gobi ; to the south they would invade the larger part of the African desert. The remains of Europe would have a very humid climate, for whilst at present the western winds alone bring us wet, all the winds would then be of oceanic origin. We can hardly go further into the discussion of the modifications which would result from such an altered state of things ; our only business is to point to the important part which the conquest of the sea plays-in the general economy of nature. 2. Ancient limits of the Black Sea— Drying-up of the Kussian Steppes. Such changes do not entirely belong to fiction. The works of Tournefort, Chandler, and Tott, those of Count Potocki, of Prince Gallitzin, and of Pallas, unite with those of the ancients to prove that the northern coasts of the Black Sea have changed very much ; and that between this sea, the Caspian, and Lake Aral, traces are to be everywhere found of the AN ANCIENT SEA. 339 former presence of the sea. Pallas (vol. x.) thinks that the salt lakes of the steppes of Russia and Tar- tary are ancient gulfs, the mouths of which have been choked up with sanrl, and which have subse- quently been considerably reduced by evaporation. Originally, says Dureau de la Malle, the Mediter- iiinean was a lake of small extent, fed by the Nile, the Rhone, the Po, and many other less considerable rivers. The ocean, making an irruption into it, inundated a part of the low sandy coasts of Spain, of Barbary, and the plains of Provence and Languedoc, and of course flooded the coasts of Egypt and Asia Minor, where it has penetrated to the foot of the mountains and hills. After that period the Mediterranean, losing much more by evaporation than it gained from its rivers and the Straits of Gibraltar, then very narrow, gra- dually contracted. But it was enlarged again, when, owing to the volcanic eruption of the Cyaaei Scopuli, the channel of the Bosphorus, and the plains in its neighbourhood, had opened a passage to the Euxine, the Caspian, and the Lake of Aral, and they were united in one sea, at least as large as the present Mediterranean. All the low plains of recent formation were covered with water afresh ; but the sea again retired until an equilibrium was established, and it lost by evaporation what it 340 THE BOTTOM OF TEE SEA. gained by the influx of water. It has since pre- served nearly its present form, the only material changes being on the low-lying coasts and about the mouths of the great rivers. 3. Movements of the Earth in the Northern Hemisphere — Subsid- ence in the North of Europe and of America — Elevation of the Polar Kegions — Sinking of the Coast of Sweden. Certain portions c-i the eartli's surface sink ; others rise, apparently perhaps without obeying any general law, but not really so. Everything goes to prove that in our hemisphere the continental mass is being elevated. A concave bend may be traced from the south of the Baltic to the Atlantic, passing by Denmark, the North Sea, and the Low Countries. Prolonged through the Channel, it is probably continued under the ocean, where, however, we cannot follow it ; but it is demonstrable again to the north-east of North America, and at Grreenland. On the inner side of this bend, which marks a zone of subsidence, the bed of the former oc^ean is in process of elevation. The line of subsidence cannot be followed to the east beyond the Baltic, for reasons we have already mentioned ; but it certainly should not stop where we can no longer demonstrate the phenomena. In the neighbourhood of Sweden, where the oscillating SEESAW MOVEMENT. 341 motion of the soil is from east to west, the appearance of the phenomenon is that of a seesaw movement : the north rises and the south subsides. New islands have appeared in the Gulfs of Bothnia and Finland :* if this should continue for two thousand years, the Gulf of Tornea will become a lake, like those which occupy the depressions in the granite all over Finland ; and eighteen hundred years later, Stock- holm will be united to this province by the Isles of Aland, transformod into an isthmus. Sir Roderick Murchison first noticed, in 1845, the existence of a line, aiound which the surface of Scandinavia appeared to turn ; but the honour of first demonstrating the movements of the land in Sweden belongs to the Swedish naturalist, Celsius, who lived at the commencement of the last century. He published his opinion that the level of the Baltic and of the North Sea gradually fell ; and the result of a large number of observatioo^ was to settle the amount of this subsidence at about one yard in a century. The rocks on the borders of the Baltic and the ocean, which had formerly been the hidden cause of much disaster to vessels, showed in his time above the level of the water. The fact that terra firma gained continually on the waters of the Gulf of r>othnia, was proved by the existence of many ancient ■* See *' Les Oscillations de I'^corce terrestre," by M. Hebert. 342 THE BOTTOM OF THE SEA. ports at a distance from the coast, by the abandon- ment of fisheries dried up or converted into shallows, and the conversion of islands into continuous land. The facts stated by Celsius were exacts but his ex- planations were erroneous. In 1802, Playfair assigned their true cause by attributing the observed changes to the movement of the land. His opinion was confirmed, in 1807, by Leopold de Buch, who discovered, when he was travelling in Scan- dinavia, the gradual elevation of the whole country between Fredericksiiall (Norway) and St. Peters- burg. He thought, without being certain, that Sweden rose more than Norway, and that the effects were more rapid in the north than in the south. At the commencement of the eighteenth cen- tury, lines had been cut in the rocks to indicate the ordinary level of the sea in calm weather. These data were examined, in 1820 and 1821, by the officers charged with the pilotage, and new lines were cut. During this interval of time the level of the Baltic had sunk, but not everywhere equally during equal times. Nilson declared, in 1837, that Scania, the most southern province of Sweden, seemed to have sunk (luring several centuries. This Swedish savan at the same time cited a number of facts in support of his novel statement. A large stone near Talbourg, the SEESA W MO \ EMENT. 343 distance of which from tlie sea had been measured by Linnaeus, in 1749, was more than 30 yards nearer the shore in 1837. Certain maritime towns were being constantly invaded by the sea, the level of some of the streets being below that of the lowest tides. An entire province, heretofore called Witlanda, and situated between Pillau, Brandenburg, and Bolga, at the period when the Teutonic Order flourished, is now completely submerged. Moreover, the soil of Denmark, of Norway, an 1 of Sweden contains de- posits of shell entirely similar to thoise which are formed at the bottom of the neighbouring seas. The soil of Scania contains none. Therefore, at no very remote period, Denmark, and certain parts of Norway and Sweden, were submerged ; but not so Scania. The first-named countries are now, on the contrary, raised above the waters, and man establishes himself in them; Scania sinks, and Witlanda has already disappeare I. Such are the observations which have enabled the celebrated geologist, Sir Roderick Murchison, to conclude, in a general manner, that the actual motion of the Swedish soil, and of the bed of the Baltic, resembles that of a seesaw, the fixed line or axis of which would pass to the north of Scania. The south falls, the north rises. m THE BOTTOM OF TEE SEA. i. Elevation of Spitzbergen — Sinking of the Western Coast, r-nd Elevation of the Eastern Coast of Greenland— Gradual Submer sion of the Forests of Labrador and of Nova Scotia — Eomaii Constructions engulfed in the Low Countries — Origin of the Zuyder Zee — Failure of the Dutch Sea-dams— The Valley of the Somme and the Coasts of Normandy follow the movement of subsidence of the Low Countries, Spitzbergeii is g*»ing through a phase of elevation. Ancient coasts are now about 50 feet above the level of the sea. Siberia follows the same move- ment. Timbers floated au'l thrown on to the coast by the waves, are now in the interior, at a dis- tance of 40 or 50 kilometres from the shore. An ancient islan 1, still separated from the continent in 1760, was connected with the mainland in 1820. The line of subsidence, of which we have spoken above, passes to the south of the British Isles, the northern portion of which (Scotland) has been elevated some 25 feet since the Roman period. It commences to the north-west, between Greenland and Iceland. The ruins of ancient monuments may still be seen beneath the water. A Danish naturalist, Dr. Singel, has proved that during the last four centuries, the sea has encroached on the land over a length of more than 900 kilometres from north to south — a circumstance which had made it necessary to remove, repeatedly, some factories COASTS OF GUEI:NLASD. 845 which liad been established on the slior(», and sub- sequently invaded by the water. The submerged forests in Fundy Bay, Nova Scotia, the subsidences at other points on the coasts of Labrador and Upper Canada, show that Davis Straits and the north-east of America are in the same liiie of motion as Greenland. Several very flourishing Danish missions existed in Greenland in the ninth century, as is proved by papal bulls. These coasts, now unapproachable on account of the ice, which entirely shuts them in, possesse 1 at that time an active and industrious population. Two towns, one cathedral, eleven churches, and three or four monasteries, show the prosperity of these colonies in the middle ages. The channel which separated Greenland from Ice- land was frozen over during the winter, but each year the passage had been free in the warm season,- and a Danish fleet carried supplies to the colonists, in exchange for the products of the chase and the fisheries. In 1408 the ice did not break up. Subsequent y, communication being interrupted, and the colonists separated froiu the mother-country, they were either massacred by the Esquimaux, or perished of cold and hunger. These coasts have since become still colder, and glaciers have covered the ruins of the 346 THE BOTTOM OF THE SEA. Danish settlements. The cause of this cooling is, very probably, a general elevation of the whole eastern coast, whilst the western coast has subsided." The elevation has had a double effect: it has (-Hminished the temperature while increasing the altitude of the country ; it has compelled the warm waters of the Gulf Stream to flow more to the east— a result which has contributed enormously to diminish the temperature of the country. We shall not b i astonished at this, if we consider the enormous influence exercised on climate by marine currents. The Netherlands, as M. Elie de Beaumont has shown, are subsiding gradually. Roman construc- tions may there be seen surrounded by water, having long since been passed by the coast-line. Peat-beds, at one time important, have been buried beneath the sea during the historic period. As the oceanic waters, filtering through a porous soil, con- tinued to rise, the Lakes of Haarlem were gradually enlarged, until at the end of the seventeenth century they united to form an inland sea. It is all in vain that men have attempted to raise powerful dams against the encroachment of the sea. The dams sink slowly with the soil on which they rest, and there is no doubt that, in a more or less distant future, the barrier which they oppose will be insufficient to protect the low-lying plains of Holland. SINKING OF THE CHANNEL. 847 The valley of the Somine and the coasts of Nor- nuiudy are also gradually sinkino-. Already the turf- pits of the valley of the Somme are below the level of the sea. Submerged forests, whose disappearance beneath the waters is proved by positive dor-u- nientary evidence, exist off the coasts of Normandy. The same may be said of the opposite English coasts. The whole of the Channel is sinking. The Straits of Dover, which would 1 ecome dry land by a slight elevation of the soil, are therefore but little likely to serve as a means of communication between France and the British Isles. There are two reasons to convince us that it must enlarge : first, in con- sequence of the action of the sea on its shores ; and, secondly, on account of the subsidence of the sur- rounding countries. 5. Two extensive Zones of Subsidence in the Southern Hemisphere — They are separated by a Zone of Elevation — The Fiji Islands have been sinking during 300,000 years. Two vast regions are subsiding in the southern hemisphere. One of them comprehends the nume- rous oceanic archipelagos — the Bass Islands, the Society Isles, the Carolinas, Gilbert's Archipelago, Marshall's Archipelago, and others. Its length is more than 8000 miles, and its mean breadth 348 THE BOTTOM OF THE SEA. more thau 1200 miles. Each year has furnished^ and still furnishes, proofs of the disappearan(!e or diminished size of islands in this immense zone. It has been seen in a preceding chapter how the incessant labours of the coral insects compensate for the sinking of the soil, and how the rapidity of the growth of the coral reefs furnishes a measure of the rate of subsidence. The size of the reefs also indi- cates the epochs sinr-e wliich the movement of the soil has continued, Tlie annual growth in height of the polypiers is 0"'*00o. Now certain reefs are several hundred yards in depth. Those of the Fiji Islands, for example, are about 1000 yards, those of the Gambler Islands about 400, and tliose of Tahiti about 80 yards. If the growth of those reefs has always been at the same rate, 300,000 years have been neces- sary for the production of the reefs of the Fiji Islands. The coral insects grow only near the surface of the water : they have therefore sunk 1000 yards at the Fiji Islands since they first commenced their work, and that has been during a period of 300,000 years. The second region of subsidence comprehends New Caledonia, Australia, and the basin of the Indian Ocean, includino- the atolls^ of the Chasfos Bank and * An aioll is a circular wall or reef of coral enclosing the sea, within which it resembles a ^lnall lake. — Tr. SUBSIDENCE IN THE SOUTHERN HEMISPHERE. 349 the Maldives. The polypiers there play a very im- portant part. Between these two zones there extends a vast zone of elevation. It is formed by a semicircle of vol- canic islands : New Zealand, the Kermandec Islands, tlie Friendly Islands, New Hebrides, the Solomon Islands, and New Guinea. Tliis volcanic line bifur- cates. One of the branches passes by the Philip- pines, Formosa, and Kamtschatka. Its direction is therefore first east and afterwards south-east. It passes the Sandwich Islands, and runs parallel with the western side of the Andes for about 2500 miles. The other branch, tending westward, passes Timor, Java, and Sumatra. The rising is very evident on the coral banks of Mauritius, the Isles of Keunion, Madagascar, the Seychelles, and the Red Sea, &c., which serve as a point of junction between the oceanic and continental zones of elevation. We have already explained by what means these variations are discovered ; they are slow but con- tinual. We are still far from being acquainted with the laws which regulate them, but it is a great honour for our century to have clearly demon- strated their existence. We may from this mo- ment say, with M. Hebert : " In spite of its apparent immobility, the whole surface of the earth is continually undergoing a balancing action 350 THE BOTTOM OF THE SEA. which is at present of such a character that tlie great continental zones are rising, whilst the great oceanic basins sink The varied surface of the earth is simply due to a series of movements, which have taken an incalculable time to produce existing results Let us carefully remember that our measures, adapted to our own comprehension arifl to the length of our existence, are borrowed from the dimensions and motions of this point in the universe which forms our habitation, and can never be re- garded, whether as respects space or time, as in any sense proportionate to the dimensions and the duration of the works of the Creator !" 361 AOTiON OF RIVERS AND CURRENTS ON THE BOTT'^M OF THE SEA. 1. Choking of Ports with Sand — Deltas, and the action of the Tide upon them— The formation of Deltas may be either favoured or retarded by Marine Currents according to circumstances — Deltas formed in Shallow Seas — Rapid growth of the Delta of the Po due to the Clearing of the south side of the Alps, and to the Damming-in of tlie Shores of the River. The movements of the submarine soil are among the most active causes of variation in the distribution of land and sea on our globe ; but they are far from being the only causes of this phenomenon. The rush of the waters is continually causing disintegration of the soil where the current is rapid, and the whole of the matter thus carried in suspension is deposited when the waters attain a position of rest in parts of the ocean where these currents cease to act. This is why ports choke up, unless a strong current of water can be made to flow through them. The sand is deposited most rapidly when the entrance to the port follows the direction of a current parallel with 352 THE BOTTOM OF TUE SEA. the coast. A dam constructed at a given distance, and turning the current towards the offing, dimi- nishes the accumulation of the sand. In consequence of the same action, sandy or muddy deposits are produced at the months of rivers, in part embarrassing tlio issue of the waters, and sometimes becoming sufficiently important to constitute islands extending to a greater or less distance into the sea, and called " deltas." We have already seen that rivers carry a large amount of rubbish of all kinds into the sea. Kocks of any size do not travel far beyond the mountains from which they are torn ; coarse gravel goes a little farther, but does not always reach the sea. In the case of the Ganges, it is found 400 miles from the mouth; whilst in that of the Po, it is not dis- coverable beyond Piacenza. Bodies carried in sus- pension go farther in proportion to their lightness. Mud and sand, therefore, form essentially the base of the delta. Fresh-water or land shells, the remains of salt-water animals, and more rarely marine shells, help to increase these deposits. Eemains of animals of large size are also found in such situations, whether they have been carried thei e by the river-current, or whether the delta has served them for a habitation. The delta of the Ganges is inhabited by tigers and alHgators; all the human FORMATION OF DELTAS. 853 bodies thrown into the river, in accordance with Hindoo custom, are stranded there. The delta of the Mississippi serves as a retreat for numerous alligators. The deltas of the Nile, the Rhone, and the Khir.e are covered with flourishing cities, while venerable forests occupy the immense islands which obstruct the mouths of the larger rivers of South America. Th^ form of a delta is triangular. The point where the river first divides is the apex of the delta. The base is the portion of coast-line comprised between the mouths of the two inferior branches. Sometimes two rivers flow into the sea at points near each other, when their deltas may be more or less confounded ; in such cases the regularity of an ordinary delta must not be expected. The two deltas combined form a network, more or less irregular, of islands and canals. The Po and the Adige, the Rhine and the Mouse, the Ganges and the Brahmaputra, are ex- amples in point. Many causes influence the collection of such debris at the mouth of a river. They have been examined with minute care in the work of M. Alexandre Vezian,* to whom we are indebted for details. The more extended the bed of a river is, the more materials it is enabled to collect, and consequently the more rapid is the formation of its delta. The * Prodrome de Geologie. 2 A 354 THE BOTTOM OF TEE SEA. two largest deltas are those of the Ganges and Mississippi. The tides tend to hinder the formation of deltas. They cause the waters of the river to be driven back daily with considerable agitation. The bed of the river is disturbed and broken up, and the great rapidity of the current of the falling tide augments such disturbance. The Thames, the Tagus, the St. Lawrence, and the Amazon are thus influenced. If, however, the current of the river be sufficiently strong to overcome that of the sea, the delta is formed, as in the case of the Ganges. An inland sea offers the most favourable condi- tions for the establishment of a delta. The Mis- sissippi, the mouth of which is at the head of a gulf, is subject to conditions intermediate between these two extremes. A current, parallel with the coast, hinders the for- mation of a delta. It seizes the materials as they are deposited by the river, and sometimes carries them to a great distance, to a spot more calm. This has happened in the instance of the Amazon. The current of this immense river is recognisable a hun- dred leagues from its mouth. The sediment which it carries in suspension is considerable ; but the great equatorial current, which flows from east-south-east to west-north-west along the shores of South DELTA OF THE GANGES. 355 America, carries the river-mud aloug with it as far as Guiana, where, far from its parent river, it forms deposits which are quite analogous to those of a delta. These deposits become gradually trans- formed into dry land, and they may be considered as the delta of the river, carried, bit by bit, to a point westward of its proper destination. How does man himself proceed to work, when be wishes to recover a few feet of land from the sea ? He deposits offshore rocks, stones, and wliatever else can be used to fill up the deep. The river at its mouth carries with it light sand and mud. At the time of its rising, immense rafts or floating islands of forest timbers encumber its bed, and, becoming entangled in its numerous curves, stop and form true dams. The river flows round them, and an island is formed. Farther on, similar islands are built up near the sea, where the deposits are continued in a shelving form, the base of which gains daily ; every hour, every minute, brings fresh materials. Nature's work never comes to a standstill. It is evident that the more shallow a sea is, the more rapidly will it fill up, and the more rapidly will the delta be formed. The great depth of the Bay of Bengal contributes to retain the formation of the delta of the Ganges. It may be clearly seen on a map of this delta, that the two principal exterior 856 THE BOTTOM OF TEE SEA. branches fill on either side the ocean depths — build- ing up two immense slopes, separated by a narrow ravine. Ultimately the two banks will become con- nected, the deep water between them being gradually filled up. The rapid formation of the delta of the Po, and the slight depth of the Adriatic, into which sea this river pours its waters, are well-known facts. But other causes have contributed very considerably to this effect ; these are the embankment of the rivers and the clearing of the forests. The clearing of the soil and the destruction of forests tend to augment the quantity of water which, in the rainy seasons, flows down into the river- courses. Thus man himself helps to increase the quantity of material that streams and rivers carry into the sea. Embankments produce similar effects by aug- menting the rapidity of the current, which, in times of flood, carries sediment much farther than when allowed to spread at its pleasure over vast plains, where it deposits great quantities of mud. The embankments of the Nile, of the Po, and of the Mississippi, show how the growth of a delta may be accelerated by narrowing the channel of the river. The great labour of embanking the Po, and effect- DELTA OF THE NILE. 357 ing the clearings on the southern side of the Alps, was performed between the thirteenth and the seventeenth centuries. Since then, the mouth of the river has advanced with great rapidity into the bosom of the Adriatic. The embankment has not only increased the amount of materials carried by the Po towards the sea, but is continually raising the bed of the river, which is actually above the level of the houses of Ferrara. Similar causes have produced similar effects in the case of the Mississippi, since human industry has taken possession of the vast region through which this river and its tributaries flow. 2. Egypt, according to Herodotus, a present from the Nile. The Egyptians, more intelligent than ourselves, take the greatest pains to store up the waters of the Nile, by means of dams, at each period of flood. They receive them in canals, so as to distribute them more completely over the soil. By this means they also diminish the foi'ce of the current, and generally succeed in mitigating the otherwise disastrous effects of the inundation. The mud, which would under other circu'ustances be carried to the sea, is depo- sited on its way, and fertilises the soil ; the materials which would form the delta are spread over the 35S TEE BOTTOM OF THE SEA. whole extent of the river's basin. The delta of the Nile, therefore, increases less rapidly than those of the Mississippi and of the Po, and this in spite of the relative smallness of the basin of the last-men- tioned river. The ancient Egyptians knew the importance of the alluvial matter carried in suspension by rivers. Herodotus (Book II. chap, x.) cites the opinion of the Egyptian priests, according to whom Lower Egypt is a present from the Nile, which has filled, by the deposition of its mud, an arm of the sea enclosed between Libya and the Arabian mountains. He adds, that if the lead be thrown at the distance of a day's journey from the sea it will come up well covered with mud from a depth of eleven fathoms. Herodotus bases his opinion on the fact that the superficial soil of this country is a blackish mud from Ethiopia, which contrasts with the sand and gravel, the ordinary soil of these countries. The Egyptian priests also remarked, in Hero- dotus' time, that under M ris, 900 years before, if the Nile in its annual overflow rose eight bits, it watered the whole of the plain below Memphis, and that it then produce 1 the same effect only when it rose fifteen or sixteen cubits. Aristotle speaks of the variation of the seas in his "' Treatise on Meteors." " Egypt," he says, " fur- DELTA OF TUB NILE. 350 nishes an example of a country becoming drier and drier ; it is entirely formed of the depositions from the Nile/' According to him, the Canopus, or western branch, is the only natural one ; the others appear to have been dug by man to facilitate drainage. Plutarch (" Isis and Osiris ") says that in ancient times the valley of the Nile was covered by the sea, as is proved by the shells met with in the neighbouring desert, and the saltness of the wells dug there. Arabian authors of the middle ages express the same opinion. It is very curious to remark, that ancient ob- servers had already sufficiently studied this ques- tion to recognise the slow but continuous elevation of the bed of the river, and the deposition of its suspended matter in the sea, so as to constitute a delta. From this elevation of the bed it results, that near their mouths, in very flat regions, the rivers often flow at a level higher than that of the surrounding plain, so that at each flood the waters spread over the surrounding country, and cannot re-enter their bed but from lakes. Often, as if uncertain of their course, the wateis divide into several branches to reunite farther on. The slightest inequality in the soil forms an insur- mo Qtable obstacle to their progress. The waters 360 THE BOTTOM OF THE SEA. seem wearied, as of a long journey — then appear to leave with regret the land which they have fertilised ; they follow a thousand capricious courses, separating only to come together again ; they heap up sand and mud, as if to reproduce at the last moment the mountains which they have destroyed in their force. But, alas ! they have no longer that power which the suddenness of their descent had before conferred on them, and they still labour to diminish it after it has already become almost insensible. It is thus also that the greatest efforts of man may only serve to paralyse his powers, when he works without the enlightenment of real knowledge ! 3. Description of the Delta of the Mississippi — A Village at Anchoi — Ships lost in the Sand and Mud of the Eiver. The Mississippi is elevated nearly twelve feet above the plain about a mile and a half from its banks. The main stream therefore has acquired a tendency to send its ramifications right and left, which soon become the subject of similar phenomena. The continual deposition of soil along the banks of the river raises its bed above that of the neigli bouring plains, and it therefore runs along the summit of a low hill. If the waters overflow, they spread on both sides of the hill, and are never able BANKS OF THE MISSISSIPPI. 361 to return to the channel which they have abandoned. They travel gradually towards the sea in innu- merable tortuous canals, named hayouSy which occa- sionally swell out to form ponds or small lakes. Like the principal stream, the hayous also undergo a process of gradual elevation of their beds. A second series of hayous branch out from the first, and a third from these ; the elevation of these hayous above the plain becomes less as the distance from the main stream increases. The entire region pre- sents an appearance opposite to that ordinarily met with. The watercourses occupy the crests of low hills, and their importance is the greater as the height of these hills increases. Irrigation becomes a very simple matter in such a country. The Mississippi extends very far into the sea. It runs out between two banks of slight elevation, which it continually lengthens. First, it converts he more or less deep sea into shallows, which soon become covered with a forest of aquatic plants and reeds. A thick layer of mud is deposited at every flood, which buries the stalks of the plants, and elevates the bottom of the sea in such a manner as to ibrrn a species of submarine delta. This deposit is increased from year to year. Immense rafts of forest timber, carried to the sea and again driven back by the waves, become covered 362 TEE BOTTOM OF THE SEA. with eartb, forming floating islands ; and being stranded on the banks described above, the growth of the latter is much facilitated. In the popular " Tour du Monde," published under the direction of Mons. E. Charton, an interesting- account is given, by Mons. E. Eeclus, of a voyage on the Mississippi as far as New Orleans. He describes all the phases of the phenomena of deltas, shows the fresh-water separated from the ocean by a moveable line of demarcation of sandy mud, forming low islands and marshes, and ultimately dry land. " All night," he says, '' our vessel dragged over a bottom of nauseous mud ; but, far from complaining, I congratulated myself on the opportunity of wit- nessing what I had travelled 2000 leagues to see. What can be more interesting, from a geological point of view, than this vast stretch of alluvial soil in a semiliquid state ! Produced by the slow cor- rosion of flowing waters during many ages from the mountain-chains of North America, this sand and clay form in the Gulf of Mexico a thick bed of from 200 to 300 yards in depth, which sooner or later, by subsidence and the influence of tropical heat, will become transformed into vast strata of rock, and will serve as a base for fertile and populous regions. In their work of creation these suspended particles are sifted by the soa into deposits of various sizes, and MUn OF THE MISSISSIPPI. 363 are tlius heaped up into islands or new shores ; or perhaps, carried away by the current of Florida, are deposited a thousand leagues farther off, on the Banks of Newfoundland. " Towards daybreak the captain thought of a means of getting off the mud-bank, and sent one ot our boats to the mouth of the river to find a pilot. Some miles ahead a long thin black line seemed to jut out into the sea, like an immense mole ; beyond this dark line the river was distinguishable like a broad silver ribbon; farther, another black line, parallel to the first, was visible; and still beyond this might be seen the blue sea-waters stretching to the horizon. The Mississippi appeared to us like a canal carried right out into the sea between two long jetties, and the forty or fifty sail, just apparent against the sky, rendered the resemblance still more remarkable : such a spectacle will one day be pre- sented, on a smaller scale, by the Suez Canal pro- jecting into the waters of the Mediterranean. *' When we approached the mouth of the river the tug slackened speed, for caution was necessary in entering the buoyed channels which lead to the entrance of the river: these passes are very dan- gerous because the currents, both of river and tide, cause the depth to vary. Ordinarily, the islands formed by the subsidence of the suspended matter 364 THE BOTTOM OF THE SEA. grow insensibly ; but, during tempests, the sub- marine configuration of the mouth changes com- pletely, and it is unsafe for ships to attempt an entrance until numerous soundings have been made. In spite of his native audacity, even our American pilot felt it necessary to cast the lead repeatedly. " At last we entered the course of the river itself, and joyfully felt the rush of the current against the sides of the vessel. Nevertheless, although sailing up the Mississippi, we could not see the banks of this won- derful river — it appeared to us like a river flowing in the middle of the sea. The only indication of the submarine banks which had been built up between the salt and fresh water, was an occasional muddi- ness just above the more elevated portions of the banks, or perhaps here and there the bank itself was visible in dim outline. As we ascended the river, the outlines became more connected ; what had pre- viously appeared as disconnected or accidental ele- vations in the submarine soil now acquired the ap- pearance of a continuous line of demarcation, and speedily assumed a more solid and definite appear- ance, until ultimately it rose, a solid bank, above the level of the surrounding water. At this point also the har, or alluvial dam formed across the river, attains its greatest elevation. " So far the water ploughed by our keel, and left SAILIXG UP Tin: MISSISSIPPI. 3Gj Inibbling in our wake, has been the undercurrent ul Dlue sea-water which flows beneath the yellow water of the river, and in the reverse direction ; but no sooner have we touched the bar, and felt the ship's progress impeded by the resistance of the mud, than the colour of the water in our wake changes to a dirty yellow, and the already muddy current is rendered sensibly thicker by tlie disturbance of the mud at the bottom. The lielmsman now requires a firm liand and a sharp eye, for the bar is nearly a mile loug, and the slightest deviation to the right or left may entangle the vessel irretrievably in the mud. If the keel once stick, its peculiar motion raises the mud, the light particles of which are carried in a state of suspension in the current, whilst the heavier settles around the hull ; the slow motion of tlie ship soon allowing it to collect in sufficient quantity so as entirely to stop the vessel, and enclose it as in a wall of rock. We passed a few yards from a magni- ficent three-masted vessel which had been thus be- leaguered, and in the attempts to disengage which fruitless efforts had been spent. Enormous banks of sand had already collected around it, and now ap- peared like great masses of floating cork. "The village of Pilotsville, the wooden huts of which were visible on the left shore, is generally known by the name of Balize. This name really belongs to 3G6 THE BOTTOM OF THE SEA another village founded by French colonisirs on the shore of the south-east channel ; but since the south- west channel has become the principal entrance to the Mississippi, the pilots have at one and tlie same time carried their industry and the name to this miserable town. Certainly few places on the earth have a more wretched appearance ; the narrow slip of earth on which the houses stand is at once the shore of the river and of the sea. The waves of the one and the floods of the other cover it in turn, and mingle to- gether in a labyrinth of slimy and offensive ditches : wherever a little solid earth permits the plants to take hold, there will be found an impenetrable jungle of v/ild sugarcane and rushes. The wooden cabins are constructed with extreme lightness, so that they may not sink in the soft soil, and to keep them as dry as possible they are perched on the top of piles like stilts. Moreover, in heavy gales, when the waves rush over the bank into the river one after another, the houses of Balize might easily be swept away if they were not anchored like ships ; sometimes, indeed, the village does drag its anchor. The miasma which encircles the town of Balize is the everlasting source of fever and death, and yet four hundred Americans courageously face these dangers, and draw what profit they can from the succour afforded to vessels in distress. SAILING UP THE MISSISSIPPI. 307 "A liglit wi]i(i blew from tlie south, and our captain wished to profit by it and sail np the river. Unhappily, tlie river winds in the most distressing nianner, and the sailors were obliged to tack about continually, to furl and unfurl only to furl again. They could scarcely use their hands for fatigue when the ship considerately stuck in the soft mud of the bank. Towards evening a tug came and pulled us out of our ridiculous position. Thanks to this power- ful aid, we arrived in less than an hour at the point where the river divides into several distinct channels. In the last hundred miles of its course the Missis- sippi seemed to me like a gigantic arm stretching out into the sea, with its fingers spread out on the surface of the water. To the west extends the Gult of Barataria ; to the east is another gulf, known as Lake Borgue ; to tlie south, between each of its channels, a little marine gulf also flows, so that the whole land-surface consists of narrow strips of coast- line, ceaselessly demolished by the waves, ceaselessly renewed by deposition from the river. In some places the bank is so little elevated above the sew level that the waves almost flow over into the Mis- sissippi ; and if the roots of the rushes did not bind the soil together with their tenacious hold, the beach would soon break down, and a new channel be made for the ' Father of Yellow Waters.' 3G8 THE BOTTOM OF THF SEA. '' The only vegetation on these narrow huiijid coasts is that of the wild sugarcane; trees cannot as yet find any hold for their roots. The first tree to be found is a poor stunted willow, which has manaoed to drao' out a miserable existence on the first sufficiently elevated mound of earth to be found — namely, one situated about twenty-four miles from the mouth of the river. A few hundred yards farther up, a little group of two or three more healthy-looking willows have managed to plant themselves ; still farther, the clusters of willows become more frequent : at last they grow in con- tinuous clumps, and, intermingling their foliage, form a curtain of pale-green, which hides the sea from the traveller, and gives a more continental appearance to the country."* 4. Eapid growth of the Deltas of the Po and of the Mississippi — Delta of the Nile enlarged by Seven Miles during the Historic Period — The Rhone. Dry land is being continuously extended seaward at 1 . mouths of rivers which have formed deltas. As the older channels get gradually choked up, a time comes when only one remains, which divides again into several i)ranches nearer the sea. At the same * Extracted from " A Voyage to New OrLans," by M. Reclus. OROWTH OF DELTAS. :-ib9 time now deposits are built ii[> against the assaults of the waves, as we have seen to be the case with the Mississippi. It results that the delta of former times is no longer that of to-day, and that the navi- o^able channels are always in course of chauij^e. The channels of the Nile do not extend more than about four yards in a year. This is partly owing to the system of canals established by the Egyptian priests, partly to the current whi(*h flows along the coast, and which carries a large part of the suspended matter towards the cast, and occasionally breaks down its banks. In the time of Augustus the sea washed against the walls of Adria (a city near the mouth of the Po) ; the shore is now eight leagues distant, in consequence of the growth of the delta of the Po. The increase from the twelfth to the sixteenth century was at the rate of about twenty-seven yards annually ; it has augmented since then, and is now at tlie rate oi about seventy-five yards. The delta of the Rhone advances, perhaps, fifty- five yards each year, and that of the Mississippi about 380 yards. The immense delta of the Ganges, situ- ated at the head of a gulf, must grow rapidly ; but, as the spot is very unhealthy, it has never been inhabited, and there are no data which would enable us to form a judgment on the subject. 2 B 870 THE BOTTOM OF TEE SEA The outward growth of the 1 eads ol deltas is proved by raany facts, but none are so striking as those which concern the delta of tlie Nile. At one time this river flowed into the sea through seven branches, of which tliere were three principal ones. Of these branches two only now reiDain — those of Rosetta and Damietta. The exterior branches (the Canopus and the Pelusiac) are filled up, and the head of the delta, which was at one time under the parallel of Heliopolis, is now about seven miles nearer the sea. In all deltas the relative importance of the various branches of the river is constantly changing. In the time of the Etruscans the course of the Po was the Po-di-Primaro, but now the principal branch is farther north. The head of the delta of the Rhone is at Aries. The western branch, now (ailed the Little Rhone, was at one time the more important. It was itself successor to a still more western branch, now dried u[). The principal course, at the present time, divides into several branches before falling into the sea; one of these will, in course of time, alone remain, as the others will gradually be filled up. ACCUMULATlOSii OF SAM). :S7J 5. Littoral accumulations — Coast-line -Murine Lagoons and Pools- Lagoons moved inland by tlie eiiccts of the Dunes in Gascoiiy — Villages buried beneath the Dunes near St. Pol-de-Le'ou in Brittany, and also in Guscony — Bordeaux menaced. The elevation of a sliore by the addition ot* fresh soil is effected by the sca-^vaves as well as by rivers. Every coast exhibits, within the limits occupied by the sea, a quantity of loose sand and rounded peb- bles. The less rapid the cunent is at the bottom of the sea, the slower is the accumulation, which, how- ever, attains great importance on low coasts, giving rise to dunes, bars, and a number of other phenomena, which we shall indicate in a few words. We have seen that the mass of loose stones, &c. thrown up by the sea at its borders, is continuous along every coast, and that it marks what is called the coast-line. When formed of fine sand, and the soil is not clayey, the action of the wind, in conjunction with the waves, causes the production of those hills of sand called dunes. Lagoons often accompany the coast-line if the shore be clayey, and if the country be sufficiently flat to allow the water to remain in any slight inequality of the soil, or to flow very slowly towards the sea. Bars and other phenomena, the study of which would carry us beyond our subject, in conjunction 372 ' THE BOTTOM OF THE SEA. with the coast-line, the dunes, and the lagoons, con- stitute the littoral apparatus. *' They combine to form a very decisive line of demarcation between the region of storms and agitation outside the sea, and the abode of peace within the land."* The coast-line, in some cases, may become a barrier which completely separates the waters of a gulf from those of the sea. But even when the coast presents no hollow for the collection of the water, salt lakes or lagoons may be formed if a line of rocks, visible or not above water, should exist at a certain distance from the shore, and form a bar to the sand or other stuff that may be washed up by the sea. The lagoon may retain one or two communications with the sea, in the shape of channels, or it may become completely enclosed. Marine ponds are deep lagoons ; they are numerous on the coast of France. That of Thau, near Cette, is one of the most remarkable. If a lagoon entirely separated from the sea does not receive any stream of water, it dries gradually, and increases in saltness. When it receives a river, its saltness diminishes. In any case, the creatures which it feeds are modified according to the changes in the composition of the water. Thus, the lagoons of Finland are inhabited by freshwater animals, and also by a kind of shrimp * Elie de Benumoiit, Le'^ons de Geohgie Pratique. FuiaiATION OF DUNES. '67H which is able to livo in water less smU thaii that of the ocean. The encroachments of the sea on dry land are not confined to inundations ; it sometimes bores beneath the sand, wliich it throws up from its bosom. The dunes (so called from the Celtic word dun, which sig- nifies an elevated spot), or sandhills, are formed on the seashore, as in the African desert, by the action of the wind on the loose sand. They present a gentle inclination towards the sea, whilst on the land-side they are terminated by an abrupt decvlivity. Their height is generally from 15 to 20 yards, but in rare instances they attain a height of 80 yards, which may be considered the extreme limit. For the rapid formation of dunes it is necessary that the sea should leave a large space bare, which subsequently it will cover with its waters and the sand it carries with it. These conditions are best fulfilled on those coasts where the daily ebb-and-flow of the tide leaves a large extent of sand exposed to the drying action of the sun and w ind. Another condition on which the increase of the dunes depends, is that the sea-winds blow more frequently than those from the land — otherwise the work of one day will be undone by that of another. The formation of dunes is sufficiently simple. The wind from the sea blowing over the sandv waste, 374 THE BOTTOM OF THE SEA. causes an inclined plane to be iunuea, up which the particles of sand are afterwards driven, and having attained the summit, fall down the declivity, which they continually enlarge. At the base another sand- Fig. 65. Vili buned undt d Dunes. hill commences its inclined plane, and the same action of the wind effects a similar transference of the sand to a third hill. The materials of each dune are thus driven from one drift to another; so that they are continually being destroyed, and as con- GROWTH OF LWNJ'JS. 3'/ 5 tinually re-forined, at a greater distaiiee frojn the sea. As the sand is carried farther inland by this process, it makes way for new supplies from the inexhaustible stores of the ocean. These waves of sand, invading the land by the impulse of the wind, have, like the sea-waves, an un- equal motion, according to the configuration of the ground. Everything must alike yield to their con- stantly advancing forces : cultivated land, forests, houses, villages, and towns disappear beneath them ; even pools of water retire before them, as in Gascony, where, under the influence of the dunes, numerous saltwater pools are pushed farther inland, and their level constantly raised. As the Mediterranean is almost tideless, the dunes are formed there with much less facility than on the oceanic coasts. On the latter examples may be cited of villages being buried like caravans in the desert. At a spot near St. Pol-de-Leon, in Brittany, where a village stood in 1666, a few sand hillocks, with a few chimneys and steeples to indicate the original site of the village, alone remained fifty years after: the dunes had advanced at the rate of about 580 yards every year. The dunes of Gascony, how- ever, do not grow with this frightful rapidity, their progress not exceeding some 25 yards annually. If the progress should remain constant, at this rate they 376 THE BOTTOM OF THE SEA. \vili reach Bordeaux in '^000 years. Several Gascon villages, the names of which are transmitted by docu- ments of the middle ages, have completely dis- appeared. The coasts of the Netherlands, La Vendee, Pata- gonia, and more especially of tlie Sahara, are among the more important fields of thi^ phenomenon. 6. Floating Icebergs— Polar Winters. As we have already explained, floating icebergs deposit a vast quantity of earthy material at the bottom of the sea. They are, in fact, one of the most powerful agents of transport. As we approach the poles, floating masses of ice are met with. They become larger and more numerous as we advance, and at a high altitude a continuous field of ice stretches before the view, and, no doubt, joins a continent which is also frozen. Great danger is incurred in an attempt to pene- trate these regions. Ships are in constant danger of being crushed between the immense masses of floating ice, some of which rise to a height of 40 yards above the level of the sea, which corresponds to a submerged thickness of 280 yards. As they advance they gradually melt, and distribute on their THE ARCTIC BEGIOXS. 377 route Ibo materials which tho\' liavo trans; lorted from tlie arctic continents, or from the beds of the polar seas. If the sailor succeed in passing- the zone \\liere these immense masses of ice float, lie may ex[)ect Fvy. 66. — Floating Glaciers. every instant to see the sea freeze up around Ids vessel and keep him prisoner for entire months, in a region where he may perish of hunger, sliould he escape the thousand-and-one more immediate dangers whicli threaten him. 378 THE BOTTOM OF THE SEA. The celebrated arctic explorers, Captain John Davis, Sir Edward Parry, 8ir John Koss, Sir John Franklin, Captain (now Sir Robert) M'Clure, Dr. Kane, Captain (now Sir Leopold) M*Clintock, and others, in their search for the nortli-west passage, have only too clearly demonstrated the dangers of any attempt to penetrate these regions. Nor ought we to omit the name of the intrepid and learned De Blosseville. Sent on an exploring expedition to the coasts of Greenland in the Lilloise, he and his companions must have perished miserably in those inhospitable regions, for not a trace has since been discovered of them. The ice-bound ship is in an unsafe position, but its release may be attended with even more danger than its captivity. Sir Leopold M'Clintock, who suc- ceeded in discovering a few remains of Franklin's expedition, says : " On the 18th of August we had arrived in the mid-channel of Melville's Bay, in Lancaster Straits, when, being unexpectedly encircled by an immense accumulation of drift-ice, we found ourselves compelled to pass the winter in the midst of one of those vast fields of ice of which I had often heard during my career as a sailor. In the course of the winter the force of the water often opened long crevices or channels in the solid vault of ice which covered it, and these solutions of continuity BREAKIXG-UP OF THE ICE. 379 were produced witli such violence, tliat often masses of ice were tlirown up, as by the effect of a miue, several feet in tlie air, and formed banks on either side of the crevice from whicli tliey had been pro- jecteh During our captivity we were able to ca})- ture in these channels of open water about 70 sea- cows, which furnished us with food for our dogs and oil for our lamps. " We did not regain our liberty until the 25th of April, in latitude 60° 30', and under circumstances which will long be remembered by those who shared in the expedition. A violent tempest arose in the south-east ; the ocean, stirred from its depths, broke up its icy crust, and hurled into chaotic disorder the broken masses of the icefield, threatening a score of times the little Fox with total destruction. Our salvation in these critical circumstances was due in the first place to Providence, and secondarily to the excellence of our screw and the form of our stem." It thus appears that M^Clintock's ship had drifted with" the ice from the 75th to the 63rd degree of latitude — that is to say, a distance of about 300 leagues from its starting-point. A violent spring storm broke up this mass of ice, which then drifted in dangerous confusion towards Newfoundland, wliere it would meet with the warm waters of the Gulf Stream, and gradually disappear in the ocean. 380 THE BOTTOM OF THE SEA. INFLUENCE OF LIFE ON VARIATIONS IN THE BED OF THE OCEAN. 1. Formation of Coral Reefs ; limit to tlieir yi'owtli — Conditions favourable to tlieir development. Animal and vegetable life inliiiences to a great extent the various changes at the bottom of the sea. We have already seen that animals of the smallest size build the most important submarine constructions, but that every other kind of existence has also a hand in this continual transformation or modification of the submarine world. The tropical seas especially swarm with an immense variety of living beings. But as in other seas, so here in warmer waters, the shores are more inhabited than the deeps, and at a little distance from the surface life ceases to exist. We will attempt to describe briefly one of the most interesting and wonderful of marine phenomena, that of the construction of coral reefs, which attain such important dimensions in the Pacific Ocean, the Indian Ocean, and the West Indian seas. CONSTEUCTION OF CORAL REEFS. 381 Polypiers continue to grow until tliey have reached the surface of the water. The construction of coral may be likened to a forest ; intervals are left com- parable to those between the branches of a tree and the trees of the forest. Animal remains — partly de- rived from the decay of some parts of the coral, partly consisting of tlie debris of molluscs and fisli — fill up the gaps, and, in the manner of a chemical cement, serve to bind the whole into a compact mass. The coral insects absorb, particle by particle, the carbonate of lime from the water, and they deposit it afterwards. The carbonate sometimes appears in a muddy form, and, hardening by exposure to air, appears very similar to chalk. This plienomenon is very remarkable in the Bermudas, where it has been studied by the naturalist Nelson: "After having observed the decomposition of shells and polypiers from the less calcareous to the clumps of meandrinae and astreae, not only in situ, but m the masses which had been detached by means of the diving-bell for the ^vorks of the arsenal, I do not hesitate to affirm a common origin for the chalk of the Bermudas and the banks of stone, more or less solid, which constitute the islands themselves— only that the latter result from the accumulation of fragments mechanically broken, whereas the rock or chalky paste is due to the de- struction, owing to prolonged submersion, of the mem- 382 THE BOTTOM OF TEE SEA. branous tissue which penetrates the whole mass, and which is then separated from the calcareous matter contained in its meshes. The formei', by its precipi- tation, forms that soft whitish substance, analogous to chalk, wliich is found in the bottoms of creeks and gulfs mixed with shelly sands, the debris of poly piers, well-preserved shells, and consi'lerable masses of meandrinae and astrese." The coral insects love warm water and constant agitation. This last circumstance gives a very cha- racteristic appearance to the calcareous deposits which accompany them. Crystals of carbonate of lime are deposited in the liquid mass, and become centres around which new molecules of the same matter group themselves. The constant agitation of the water gives a rotatory motion to the little solid nuclei already formed, whil&t continued deposition goes on in such a manner as to give them a spherical form. The rock thus acquires a peculiar texture, called oolitic. Lastly, we may observe that coral does not flourish except in limpid water and on a rocky bottom. LWIiiG FORCE IRRESISTIBLE. 883 2. Life and Inanimate Nature — Coral Insects die in th(^ calm of Deep Waters — Explanation of tiie formation of tlie Dei p Reefs of the Pacific Ocean — Coast Reefs — Broken Reefs — Barrier Reefs of Australia — How the Coral Reef becomes an Island. Darwin observes, in bis beautiful work on tbe formation of Coral lieefs, that wben the ocean hurls its waves against the shores of tlie Pacific Islands, they find in it an invincible enemy. Never- theless, its force is sometimes withstood by obstacles apparently very feeble. It never seems to repose. Its mighty billows, raised by the ti-ade-winds, roll in- cessantly against the shores. The turbulence of the water lashed into foaming breakers is much greater on the shores of these islands than in our temperate regions; and no one could observe them without feeling convinced that rocks even of granite or quartz must eventually yield to forces so consider- able, and be utterly demolished. These little isles of coral, however, so low, so insignificant, resist suc- cessfully the assault made upon them, thanks to the intervention of another force, in some sort opposed to the first, which takes part in the struggle. The organic forces detach, particle by particle, from the foaming breakers the carbonate of lime, which they afterwards reunite in a symmetrical form. Myriads of architects are employed in this work night and 384 THE BOTTOM OF THE SEA. day, and we see their soft gelatinous bodies, aided by the law of vitality, quell the brute power of the waves, against which neither the industry of man nor tlie inanimate forces of nature would be able to struggle with success. Life, apparently weak and mean, but in reality active and full of resources, issues victorious from an incessant struggle, in which inert matter threatens momentarily the destruction of the i'rail enemy whose strength she continually feeds. I oral insects prefer a current of water. It carries away from them the matters rejected or secreted by their bodies, and be- come innutritions, or even as dangerous to them as poisons. The cahn reigning in deep water is death to these minute animals. The coral polypi live near the surface : according to Darwin and Dana, they never build at a depth ex- ceeding forty yards, whilst other species live at much greater depths, even reaching to 400 yards. How, then, can we explain the great depth to which some of the larger coral banks, like those of the Fiji Islands, descend ? Darwin has discovered a simple explana- tion of this fact. Founded on numerous observa- tions, it entirely accords with what geology teaches us respecting the crust of the globe. Since the coral insect does not live out of the water, the growth of the reef ( annot go on above its surface. FORMATLOS OF CORAL JSf.AXDS. 'ASt Kere the sea itself assists in raising the elevation of one part of the reef by disintegrating or hrealcing up others. When the reef is of sncli a lieight, says Chamisso,* that it is k^ft almost dry at low-tide, the coral insects abandon their work. Above this line a continuous stony stratum may be observed, com posed of the shells of molluscs, of echinoidaB with their points broken, and of fragments of cora' cemented together by a calcareous sand produced b) the pulverisation of the shells. The heat of the sun often penetrates this mass when it is dry, and causes cracks in different directions ; then the waves have sufficient power to break off masses of coral, some- times six feet long, and four or five feet in thickness, and to throw them up on the reefs, whereby the crust is so elevated that high-tide only covers it at certahi seasons of the year. The calcareous surface does not, however, suffer any subsequent disturbance, but offers a soil to the seeds of trees and plants brought by the waves, upon which the vegetables grow with sufficient rapidity to form very soon a covering for its dazzling white surface. Even before the trees become sufficiently bushy to form a wood, the sea- birds build their nests on the once bare reef; and land-birds, lost in the ocean waste, fly to it as a place of refuge ; and still later, long after the coral * Expedition of Kotzebue. 2 c 3S6 THE BOTTOM OF THE SEA. insects have finished their work, man appears, and builds his hut on the now fertile soil. The coral insects, unable to live in fresh-water, are interrupted in their work wherever a river pours its tribute into the sea. The reefs are also subject to very sudden breaks at a short distance from the sea, if the b'~*ttom be a very steep inclines ; such are the coast reefs, or broken reefs, so called on account of their situation and of their frequent breaks. Sometimes a channel of considerable width, and of more or less depth, separates the reef from the coast. It is then called " a barrier reef." Some of these are of very great extent. One, on the coast of New Caledonia, is 100 leagues long ; another follows the eastern coast of Australia for a distance of 400 leagues, almost without interruption. The channel which separates this reef from the mainland is from 60 to 100 feet in depth, and its width varies between 15 and 50 leagues. Coral reefs are circular when the coast opposite to which they are built is that of a small island. If, instead of an island, there is a shallow, such as would be produced by the summit of a submarine mountain, the reef becomes converted into an island, in the form of a ring, in the midst of which is a lagoon, generally communicating with the ocean, although occasionally it is quite enclosed. Sometimes the lagoon fills up, and '^ ATOLLS" OF THE I'ACTFW. 887 the island takes the form of a circular plateau. In either case such au island is called an atoll. The recurrence of this plienomenon is too frequent, more especially in tlie Pacific Ocean — its cause has been too long a hard nut for the savans — for us to pass it by without saying a few words in respect to it. The shape of these ,islan Is led to the belief, that the coral insects had built tlieir reefs on the edges of submarine craters. The general resemblance be- tween them and certain volcanic islands had struck the first observers. Such islands (as Barren Island and others) presented a circular belt of mountains, interrupted in one spot by a canal forming a com- munication between the sea and the interior lake. The mountains are the sides of a crater, the bottom of which has been filled up with the invading waters of the ocean. The same general character is at first evident in the appearance of an atoll. But how can the size of craters which correspond to atolls be explained ? — eleven leagues in diameter, such as that of Bow Island, or of double the diameter, as in several of the Maldive Islands ? Again, how is it possible to admit that the Pacific Ocean is studded with so many volcanoes, all of which attain about the same height of 40 yards ? Lastly, how can the theory of submarine volcanoes be applied to the formation o.f 388 THE BOTTOM OF THE SEA. barrier reefs, of which atolls are evidently only a particular instance ? We Imve already explained that the bottom of the sea is undergoing a constant though very slow variation. It rises in some points to sink at others ; and this movement, which requires centuries to make itself evident, is the most energetic agent of the modifications occurring on the surface of our planet. Darwin has very ingeniously applied the knowledge of this general fact to the explanation of atolls. We give his theory in a few words, as follows : The coral insects do not live beyond a depth of forty yards. They are therefore confined to the shallows, or to the neighbourhood of coasts. On the other hand, the close proximity of land troubles them for various reasons, among which may be mentioned the outflow of the soft waters of rivers, and the agi- tation which causes mud, &c. to be held in sus pension. They therefore remain at a certain distano^ from the shores. Sooner or later the waves break ap a portion of the coral barriers, and wash the frag- ments over the reef into the clear channel which it thus tends to fill. When the reef reaches the surface of the water the existence of its artificers becomes impossible. But if the soil be slowly sinking, there must always remain sufficient water above the colony to permit of its continued growth. nJHMATIOX OF ''ATOLLS." 389 Take the instance of an island slowly sinking. The coral forms at first a continuous reef around the coast ; as the level sinks, the coral grows upward. The island diminishes at the same time in size, and leaves a channel between it and the reefs, which then (Continue their growth. A time would at length come when a coral reef, in the form of a ring, would be visible surrounding a lagoon, in the middle of whicli would be seen the remains of the primitive island. At last, when the island shall have completely dis- appeared, the coral ring — thanks to the persistent eiltbrts of the coral insect — will remain ; it will sur- round a lake of less depth in the centre than at tlie sides. Later, the earth continuing to sink, the depth of the middle of the lake will continue to increase, whilst the edges will be slowly filled up with the debris arising from the disintegration of a portion of the coral reef. The lake will have become like any other — the atoll will be complete ; it will itself per- haps finally disappear, or increase in size, if the movement of the earth's crust should change its direction. The same theory evidently explains the forma- tion of coast reefs and barrier reefs, since these are nothing more than the elements of the atoll built in a peculiar situation relative to the land. m) THE BOTTOM OF THE SEA. 3. Slowness of the growth of Coral Reefs — Florida Keys — Destruetiou of Coral Islands during a tempest in January 1865 — Regions in which Coral Reefa are found. Although it is certain that the growth of coral reefs is very slow, yet we have no very precise obser- vations on this point. Dana estimates the growth of tlie madreporic polypier at the rate of (0'^*41) more than a foot, annually. According to an observation by Hunt in West Key, Florida, in 1857, a meandrina increased six inches in radius in eleven years. According to the observations of the same naturalist, an occulina grew rather faster. Some large specimens of meandrinse, observed by Ehrenberg in the Bed Sea, w^ould thus appear to be thousands of years old, and must at least have been contemporaneous with Moses. But Ehrenberg's esti- mate of size was perhaps a little exaggerated. The growth of a reef is much slower than that of the coral which composes it. The sea incessantly effects its partial destruction. Sometimes, indeed, the violence of the waves uproots it completely. Such a case occurred in the Palmerston Islands in January 1865, as described by Captain Dunn, of the English brig Annie Laurie, in an account to the DESTItUCTJON OF CORAL ISLANDS. 'A'.)\ United States' consul at Tahiti.* This sailor had encountered a terrible linrricane in soutli latitude 19° 20', west longitude 102°. '^ found," says he, " the islands of this group in a deplorable state. Tlie Falmerston group originally numbered seven islands— six only now remain ; the north-easterly one, and a part of the coral reef, having entirely dis- appeared." Coral reefs and islands are only developed in tro- pical seas. They are, however, exceptionally found in the Bermudas, in latitude 33° N., a circumstance due to the warmth of the waters of the Gulf Stream which flows by these islands. They are not met with on the western coasts of Africa and America, in consequence of the diminution in the temperature of these parts, occasioned by the cold marine currents from the poles. In no part are the coral reefs so extensive as on the coasts of New Caledonia and Australia. In fact, these seas have in consequence been designated the Coral Seas. The atolls of Tahiti and of the Bass Islands are surrounded by sea at a mean temperature of 77° Fahr. Near Peru and Chili the mean tempera- * Extract from a letter by Mr. Withing, Commodore in the American Navy, inserted in the Bulletin International de I Obaer- vatoire Imperial de Paris. 392 THE BOTTOM OF THE SEA. ture of the sea is 60° Faiir. A difference of tem- perature, amounting to 17° Fahr., therefore arrests the growth of the coral reefs. The Persian Gulf, the Ked Sea, and that part of the Indian Ocean comprised between Africa and Sumatra, are also very rich in coral. We must, however, remark that these seas have the highest temperature of any on the globe. For the same reason coral flourishes in the seas of the West Indies, and on the eastern coast of Florida. The researches of Agassiz show that the entire peninsula of Florida is formed of rocks belonging to the present epoch, and that these rocks are principally composed of coral reefs and marine shells. The southern and western coasts of Florida are surrounded by an immense number of islands, separated one from another by very narrow channels. These islands are in many instances connected at low-tide, or even sometimes only sepa- rated from dry land by flat marshes. These islands, designated '' Keys," form concentric lines fronting the continental shore, from which they do not extend a great distance, the most remote being ten leagues off. They rise little more than from six to twelve feet above the level of the sea ; and, like the land itself, are composed of coral, both in masses and in sand thrown up by the sea, the VEGETABLE DEBRIS. 393 whole cemented together by tlie infiltration of CiU'- bonate of lime. A coral reef, still inliabited by the animals, runs parallel with the Keys, following the same curves, and at a distance varying from 2000 to (JOOO yards. Between the reef and the Keys there is a navigable channel (six or seven fatiioms in depth), which com- municatt'S with the opc^n sea by a number of channels traversiniif the coral reef. Generally speaking, the banks of coral forming the reef do not reach to the surface of the sea ex- cept at particular points, where the accumulation of broken coral, &c. has initiated the formation of little keys. The Gulf Stream flows beyond the reef of living coral. 4. Algse — Submarine Forests and Prairies — Floating Seaweed of th-! Sargossu Seas — Exten;,ion of the Coasts l>y the llhizophora Mangle. Marine vegetation, like marine animals, leaves its debris to accumulate at the bottom of the sea ; but, as we have before explained, their range is much more limited than that of the animals, as they are principally confined to the shallow parts of the sea and to the neighbourliood of coasts. Their pro- 394 TMJl bottom OF THE SEA. digious growth results in the formation of submarine prairies, which serve as a retreat for thousands of animals. The tangled roots of the algae serve to bind together and strengthen the loose bottom of the sea, and in some oases near the coast favour the extension of the land into the sea — thus tliemselves assisting to diminish the extent of the domain they inhabit. In the middle of oceans, more particularly in the Atlantic, enormous quantities of seaweed are met with, which have no hold on the bottom of the sea, in these parts of great depth. The quantities of these plants are so enormous, that the first sailors who met with them mistook the appearance they presented for dry land, and were terrified to find their vessels becoming more and more entangled in the weeds which thus hindered their progress. It is now known that these immense accumulations of seaweed are due to a species of circular current in the vast basin of the sea, towards the centre of which all the loose floating dehris detached from the coasts tends to converge. A tree, the Bhizojohora mangle (mangrove), has a remarkable influence on the extension of the coasts of Guiana, uniting its action with that of the equa- torial current, which, as we have already seen, transports the delta of the Amazon, fragment by COAST VEGETATION. 305 fragment. This exemplifies the variety of Nature's means for producing the same result. The mangrove grows abundantly on low coasts and in lagoons. Its penlaut branches ultimately form its roots. At first they swing in the air, of which tliey retain the moisture like the finest sponge. When they reach the soil they continue to grow and increase in size, penetrating the mud like ordinary roots. They resemble so many columns intended to support the gigantic branches of the mangrove. Each branch thus curiously rooted becomes a new trunk, wliich will ultimately transmit sap and strength like the parent stem. The roots going out from the new trunk give more solidity to the marshy ground, and enable the natives to penetrate the forests formed of this tree. The mansjroves take possession of all the shallows as they are formed. The mud, and all kinds of floating bodies, are arrested by their roots as by a fine net. The algoe consolidate the newly-formed land at the sea- side, and the accumulation of sediment elevates it on the land-side. The soil in this part soon becomes too dry to continue to support the mangroves. The cocoanut and other trees replace them, and by their presence complete the conquest of the continent over the ocean. 896 THE BOTTOM OF THE SEA. INSIGNIFICANCE OF MAN COMPAEED WITH THE OCEAN. The reader has now been introduced to a little museum of submarine wonders, by a guide who has sometimes perhaps trespassed on his patience, but who has aimed, at least, to be instructive without being dull. A general idea of the form of the ocean- bed, and of some of the mysteries concealed in the abyss of waters, has, we may hope, been clearly given. Aided by the apparatus of the diver, we have been able to enjoy a few moments of submarine life, and to advance some steps in the more frequented valleys of the ocean landscape. Is the author to blame if he cannot find the means for extending these excursions still further — if he cannot defy the very laws of nature— set at naught the pressure of 800 atmospheres, under which are hardening the marvellous stratifications upon which our descendants will live and flourish — see without light, and surpass in agility and force the monsters who would make us their prey? While we are anxious that these lacunae in our knowledge of the sea should be filled TELEGRArniC CABLES. 397 up, it is only prudent not to be too venturesome in an element for whicli we are not adapted. Standing on the shore, we look with wonder on that cable fixed to the rocks, and slowly unrolling from a chain carried by a ship steaming seaward. It would almost look as if the hardy seaman had shrunk from trusting himself to a desert without a landmark, and had contrived this means of preserv- ing his communication with the shore. But we know well enough that he has no need of that thread to guide him safely over the vast labyrinth of waters. That cable means something quite dif- ferent. If we choose to examine the shore-end, we shall find that a few copper wires care- fully enveloped in gutta-percha occupy the centre. Around tliis nucleus is a firmly-twisted cord of iron. The heart of the cable is thus protected so that nothing may interrupt the track destined for the transmission of thought. When resting on the bottom of the ocean, this simple apparatus shall serve as the medium of communication between one human being and another who wish to converse together though thousands of miles apart. While 'a just pride may be felt in the audacity and good fortune which has enabled man to make a pathway for thought over the bottom of the abyss, there is yet much in this very achievement to make S9S THE BOTTOM OF THE SEA. US sensible of our littleness. After all, though we can make signals through the cable, and see how they work at the two extremities, what do we know of the whole chain of communication, or of the power which we have so audaciously forced into our service ? We are ignorant of a thousand mysteries in the route, and the work of the ocean goes on with small respect for the noble destination of the electric submarine conductor of thought. Sponges, algse, polypiers, anatiferse, and serpularise freely make use of it as their abode — feeling no disquiet, whatever secrets of human giief, or joy, or ambition traverse their support. A rupture occurs, however, and they who laid the cable fish it up again, at tlie same time lifting out of their element the imprudent adven- turers who had fastened upon the rope. He studies them, and consoles himself for his ignorance, as the hare laughed at the fright which the frog caused him. The multitude of animals which cover the cable serve not only to hide it from view, but to increase its volume three or fourfold. That represented in the engraving has certainly not been very long under the water. Tlie animals and plants, at first taken by surprise, have to get accustomed to its presence before they weave around it its oceanic vestment. When the cable is laid at the depth of some FOSSILISED CABLES. 3^9 thousands of yards, the operation lor its recovery is extieiiiely delicate and hxborious. Any agitation of the ship might injure it; its weight, added to that of the animals and plants which have made it their home, would often be sufficient to make it break, and in such a case the broken end falls back into the ocean. Fig. 67.— Telegraphic Cable at the Bottom of the Ocean. Once more settled at the bottom, it serves, as before, for the support of the living beings who clothed it with their strange forms after having for an instant, by its fall, disturbed the calm repose of the sub- marine solitudes. At some remote period, when the 400 TEE BOTTOM OF THE SEA. work of ages shall have raised the bottom of the sea above the waters, and the mountains, which now form the grandest features of the earth's surface, shall have sunk beneath the waves, the successors of the present race of mankind will look with astonish- ment on this new species of fossil, the relic of a for- gotten civilisation, buried out of sight in the same way as the vestiges of the past which we ourselves are so interested in studying. Shipwrecks, too, with the debris of their various freights, will lend their irrefragable testimony to the former existence of man, and increase the perplexity of the geologists of the future. Still more, in the midst of the most sharply-defined marine deposits, the observer will discover the remains of our vanishing race. He will see artificial tunnels pierced through the most varied strata ; and in these, at least, he will find evidence of, our present labours to reward his researches. If herealHier, not contented with piercing the mountains to avoid the labour of ascent and descent, we drive our roads beneath the seas them- selves, what would come to pass ? Above our secure highway, storms and cyclones would pass harmlessly ; we should hear, perhaps, their fearful music, and be deafened by the roar of the waves, or the rush of the locomotive with its ugly train of carriages ; but we gliould speed with the swiftness of the wind &om one , TUNNELLING UNDER THE SEA. 401 ocean shore to another, and defy the caprices of the winds and waves. But the geologists and engineers of former ages need not despair. We are yet very far from the accomplishment of these marvels. For a long time to come the monsters of the deep will make sport of our telegraphic cables ere they fly before the breath of the locomotive, and the discordant noises of the submarine tunnel. In the meantime, as a foreshadowing of what may be anticipated for the distant future, the Thames has been securely tunneled, and there is much talk of plans for cheating the storms of the English Channel by driving a road beneath it from Dover to Calais. It may be thought there is too much bravado in the project, but the Channel is little more than a stream compared with some of the American rivers, and the depth of the water in several points is not more than from 20 to 25 feet. Even were this design accomplished, we should be far indeed from attacking the ocean itself. Until, as the skill of our engineers progresses, we lose all dread of anything crushing in our tunnels, the sea wiU demand innumerable victims, and swallow up many a rich argosy. It would be in- teresting to make an approximative estimate of our gains and losses by the ocean, so as to ascertain on 2 D 402 TEE BOTTOM OF THE SKA. which side the balance of the account lies. But a mere enumeration of the oceanic imposts wouhl be tedious, while a history of our gains, of the various means by which man compels the ocean to pay him tribute in return, would be too large a subject for the scope of this little book. Let us rather turn from a subject so full of painful memories to contemplate man in contrast with the grandeur of creation. The thin pellicle of the earth's crust, which we laboriously scratch here and there in the accomplishment of our great designs, hardly counts for anything in the harmony of the universe, even as a whole ; its modifications by our labours are of small account indeed, whether re- garded for their grandeur or their durability. If the intelligence of man has placed him at the head of the creation, the feeble influence that he can exercise over Nature ought to humble his pride. All that he can accomplish by physical labour is almost imperceptible by the side of the work effected by the microscopic infusorise; man, th^ giant, is dwarfed in results by the almost invisible atom ! €l)arlcs Bcribnet ^ Co., 654 Broadway, New York, HAVH JUST COMMKNCBD THH HUHLICATION OF t^^f XHusf^raf F& Hikarg of Mon&Frs. This Library is based upon a similar series of works now in course of issue in France, the popularity of which may be inferred from the fa(5t that OYER ONE MILLION COPIES have been sold. The volumes to be comprised ii. wi.. juries are all written in a popular style, and, where scientific subje6ls are treated of, with care- oil accuracy, and with the purpose of embodying the latest discoveries and inventions, and the results of the most recent developments in every de- partment of investigation. Familiar explanations are given of the most striking phenomena in nature, and of the various operations and processes in science and the arts. Occasionally notable passages in history and re- markable adventures are described. The different volumes are profusely illustrated with engravings, designed by the most skilful artists, and execu- ted in the most careful manner, and every possible care will be taken to render them complete and reliable expositions of the subjects upon which they respectively treat. For THE FAMILY LIBRARY, for use as PRIZES in SCHOOLS, as an inexhaustible fund of ANECDOTE and ILLUSTRATION for TEACHERS, and as works of instruction and amusement for readers of all ages, the volumes comprising TIIK JLLUS TRATED LIBRARY OF WONDERS will be found unexcelled. I 'le following volumes of the series have been published : — Illustrated Library of Wonders. pHE WONDERS OF OPTICS.— By F. Marion. Illustrated with over seventy engravings on wood, many of them full-page, and a colored frontispiece. One volume, i2mo. P"ce j5t 50 For specimen illustratwr ftfe page 81. In the Wonders of Optics, the phenomena of Vision, including the struc- ture of the eye, optical illusions, the illusions caused by light itself, and the influence of the imagination, are explained. These explanations are not at all abstract or scientific. Numerous striking facts and events, many of which were once attributed to supernatural causes, are narrated, and from them the laws in accordance with which they were developed are derived. The closing section of the book is devoted to Natural Magic, and the properties of Mir- rors, the Stereoscope, the Spectroscope, &c., &c., are fully described, to- gether with the methods by which " Chinese Shadows," Spectres, and nu- merous other illusions are produced. The book is one which furnishes an almost illimitable fund of amusement and instruction, and it is illustrated with no less than 73 finely executed engravings, many of them full-page. CRITICAL NOTICES. "' The work has the ment of conveying much useful sdendhc mformation in a popxilaj manner." — Phila. North. American "Thoroughly admiraV)le, and as an mtro(lu<5lion to this science fur the geiTiral reader, leaves hardly anything to be desired." — A'. Y. Evening Post. "Treats in a charming, but scientific and exhaustive manner, the wonderful subjeift of optics." — Cleveland Leade^- " All the marvels of light and of opucal illusions are made clear." — N. V. Observer. yH UNDER AND LIGHTNING. By W. De Fon viELLE. Illustrated v/ith 39 Engravings on wood, nearly all full-page. One volume. i2mo . . . . $1 5c For npfcim&n iUuntrations see page 14. Ihunder and Lightnings as its title indicates, deals with the most star- tlmg phenomena of nature. The writings of the author, M. De Fonvielle, have attracted very general attention in France, as well on account of the happy manner in which he calls his readers' attention to certain facts liereto- fore treated m scientific works only, as because of the statement of others Illustrated Library of Wonder:^. often observed and spoken of, over which he appears to throw quite a ne\» light. The different kinds of lightning — forked, globular, and sheet light ning — are described ; numerous instances of the effe6ls produced by this won- derful agency are very graphically narrated ; and thirty-nine engravings, nearly all full-page, illustrate the text most effe6lively. The volume is certain to excite popular interest, and to call the attention of persons unaccustomed to observe to some of the wonderful phenomena which surround us in this world. CRITICAL NOTICES " In the book before us the dryness of detail is avoided. The author has g^ven us all the scientific information necessary, and yet so happily united interest with irvstnidtion that no person who has the smallest particle of curiosity to investigate the subjedt treated of can fail to be interested in it." — A^. Y. Herald. " Any boy or girl who wants to read strange stories and see curious pictures of the do- ings of elecfb-icity, had better get these books." — Our Voung^ Folks. " A volume which cannot fail to atti^A attention and awaken interest in persons who have not been accustomed to give the iubjeecimen illttstration see page I7« This volume is devoted to the wonders of Ancient Egypt during the time of the Pharaohs and under Sesostris, the period of its greatest splendor and magnificence. Her monuments, her palaces, her pyramids, and her works of art are not only accurately described in the text, but reproduced in a series of very attra6tive illustrations as they have been restored by French explorers, aided by students of Egyptology. While the volume has the attradlion of being devoted to a subje6l which possesses all the charms of novelty to the great number of readers, it has the substantial merit of dis- cussing, with intelligence and careful accuracy, one of the greatest epochs in the woild's history. Illustrated Library of Wonders. CRITICAL NOTICES. " I think this a good book for the purpose for which it is designed. It is brief on earl. head, lively and Rraphic, without any iheairical artifices; is not the work of a novice, but of a real scholar in Egyptolnc.y, and, .ts far as can be ascertained now, is liisiory." — J A MES C. MOFFA T, Profrssor in Princetoi Theolo^cnl Seminary. "The volume is full of wonders." — Hart/onl Coura.nl. " Evidently prepared with great care." — Chicago Evening Journal. " Not merely the curious in antiquarian matters will find this volume attra(5live, but the general reader will be pleased, entertained, and informed by xV— Portland Ar^ns. "The work possesses the freshness and charm of romance, and cannot fail to repay all who glance over its pages." — Philadelphia City Item. ADVENTURES ON THE GREAT HUNllNC; GROUNDS OF THE WORLD. By Victor Meunier. Illustrated with 22 woodcuts. One volume i2mo . . $1 50 For specimen illustration see page 1 8. Besides numerous thrilling adventures judiciously sele(5t;ed, this work con- tains much valuable and exceedingly interesting information regarding the different animals, adventures with which are narrated, together with accu- rate descriptions of the different countries, making the volume not only interesting, but instru6live in a remarkable degree. CRITICAL NOTICES. " This is a very attracflrve volume in this excellent series." — Cleveland Herald. "Cannot fail to prove entertaining to the juvenile reader." — Albion. " The adventures are gathered from the histories of famous travellers and explorers, and have the merit of truth as well as interest." — N. Y. Observer. " Just the book for boys during the coming Winter evenings." — Boston Daily Journal. WONDERS OF POMPEH. By Marc Monnier. With 22 illustrations. One volume i2mo . . $i 50 For specimen illustration see page 1 9. There are here summed up, in a very lively and graphic style, the results of the discoveries made at Pompeii since the commencement of the exten- sive excavations there. The illustrations represent the houses, the domes- tic utensils, the statues, and the various works of art, as investigation gives every reason to believe that they existed at the time of the eruption. Illustrated Library oj IVofuIcrs. I CRITICAL NOTICES. i " It is undoubtedly one of the best works on Pompeii that have been published, ar j h,is this advantage over all others — in that it records the results of excavations to the la.esi date."— iV. V. Herald. "A very pleasant and instrudlive book." — Baii. Meth. Prot. "It gives a very clear and accurate account of the buried cw^y—Pctland Transcript. Sttiilime fn Katurc. THE SUBLIME IN NATURE, FROM DESCRIP- TIONS OF CELEBRATED TRAVELLERS AND WRITERS. By Ferdinand Lanoye. Illustrated with 48 wood- cuts. One volume i2mo $1 50 For specimen ilhcstration see page 20. The Air and Atmospheric Phenomena, the Ocean, Mountains, Vulcanic Phenomena, Rivers, Falls and Cataracts, Grottoes and Caverns, and the Phenomena of Vegetation, are described in this volume, and in the most charming manner possible, because the descriptions given have been seledled from the writings of the most distinguished authors and travellers. The illustrations, several of which are from the pencil of Gustave Dore, re- produce scenes in this country, as well as in foreign lands. ' CRITICAL NOTICES. " As a hand-book of reference to the natural wonders of the world this work has no tM^^rvox.^''— Philadelphia Inquirer. " The illustrations are particularly graphic, and in some cases furnish much better ideas of the phenomena they indicate than anything short of an actual experience, or a pano- ramic view of them would do." — N. V. Sunday Times. THE SUN. By Amedee Guillemin. From the I rench by T. L. Phipson, Ph.D. With 58 illustrations. One volume i2mo $1 50 For specimen illustration see page 21. M. Guillemin's well-known work upon The Heavens has secured him a wide reputation as one of the first of living astronomical writers and ob- servers. In this compa(5l treatise he discourses familiarly but most accu- rately and entertainingly of the Sun as the source of light, of heat, and of diemical a6lion ; of its influence upon living beings ; of its place in the Planetary World ; of its place in the Sidereal W< rid ; of its physical and Illustrated Library of Wotidcrs. chemical constitution ; of the maintenance of Solar Radiation, and, in con- clusion, the question whether the Sun is inhabited, is examined. The work embraces the results of the most recent investigations, and is valuable for its fulness and accuracy as well as for the very popular way in which the subjed is presented. CRITICAL NOTICES. "The matter of the volume is highly interesting, as well as scientifically complete ; the style is clear and simple, and the illustrations excellent."— iV. Y. Daily Tribune. " For the first time, the fullest and latest information about the Sun has been comprised in a single -voXwrsM.^'— Philadelphia Press. "The work is intensely interesting. It is written in a style which must commend itsell to the general reader, and imparts a vast fund of information in languiige {rQc from asiromt mical or other scientific technicalities." — Albany Evening Journal. "The latest discoveries of science are set forth in a popular and attradlive style."— /'ort- land Transcript. " Conveys, in a graphic form, the present amount of knowledge in regard to the luminous centre of our solar system." — Boston Congregationalist. WONDERS OF Gl.ASS-MAKlNG ; Its Descrt hon AND History from the Earlip:st Times to the Present. By A. Sauzay. With 63 illustrations on wood. One volume i2mo 5 J 50 For specimen illustration sec page 22. The title of this work very accurately indicates its charader. It is writ- ten in an exceedingly lively and graphic style, and the useful and ornamen- tal applications of glass are fully described. The illustratirms represent, among other things, the mirror of Marie de Medici and various articles manufadlured from glass which have, from their unique chara61er, or the ass< ciations conne(5ied with them, acquired historical interest. CRITICAL notices. "All the information which the general reader needs on the subjed will be found hcie in a very intelligible and attraftive form." — N. Y. Evening Post. "Tells about every branch of this curious manufadlure, tracing its progress from ilie re- motest ages, and omitting not one point upon which information ran be desired "- -B,'ston Post. " A very useful and interesting book '" — .V. V. Citi-^en. ni It st rated Library of Wonders. " An extremely pleasant and useful little book."— i\^. Y. Sunday Times. " The book will well repay perusal." — N. V. Globe. A most interesting volume." — Portland Argus. " Graphically told." — N. Y. Albion. " Young people and old will derive equal benefit and pleasure from its perusal."- - iV. Y. Ch. Intelligencer. WONDERS OF ITALIAN ART. By Louis Viardot. With 28 illustrations. One volume i2mo . $1 50 For specimen illtistration see page 23, As a coinpa6l, readable, and instruflive manual upon a subje6l the ex- position of which has heretofore been confined to ambitious and expensive treatises, this volume has no equal. In style it is clear and attra(5tive ; its critical estimates are based upon thorough and extensive knowledge and sound judgment, and the illustrations reproduce, as accurately as wood engravings can do, the ^eading works of the famous Italian masters, while anecdotes of these great artists and curious facts regarding their works give popular interest to the volume. W^t ^umaii JSotrff. WONDERS OF THE HUMAN BODY. Erom the French of A. Le Pileur, Do6tor of Medicine. Illustrated by 45 Engravings by Leveille. One volume i2mo . $i 50 For speciinen illustration see page 2/[. While sufficiently minute in anatomical and physiological details to satisfy those who desire to go deeper into such studies than many may deem necessary, this work is nevertheless written so that it may form part of the ^lomestic library. Mothers and daughters may read it without being re- pelled or shocked ; and the young will find their interest sustained by incidental digressions to more attra6live matters. Such are the pages re- ferring to phrenology and to music, which accompany the anatomical description of the skull and of the organs of voice ; and the chapter on artistic expression which closes the book. Numerous simple but at •T(riiv<^' enijrnvin;:!-; elucidate the work- k NE]N SERIES Of S^p IHusfralPpb Eifirarg of Wonbprs, ENLARGED IN SIZE, IN A NEW STYLE OF BINDING, AND EDITED BY PROMINENT AMERICAN AUTHORS. ■Jhe extraordinary success of the Illustratkb Library of Wondkrs has encouraged ihc i^blishers to still further efforts to increase the attractions and value of these admirable books. In the new scries, which has just been commenced with Thk Wonders of Waterj the size of the volumes is increased, the style of binding changed, and th-; successive volumes are edited by distinguished American authors and scientists. T\k 'ollowing volumes will introduce THE SECOND SERIES OF THE Illustrated Library of Wonders. MOUNTAIN ADVENTURES. (39 Il- lustrations.) Edited by J. T. Headley. WONDERS OF ELECTRICITY. Edited by Dr. J. W Armstrong, Presi- dent of the State Normal School Fredonia, N. Y. WONDERS OF VEGETATION. (Over 40 Illustrations.) Edited by Prof. Schki.k De Vere. WONDERS OF WATER, (64 Illus- trations.) Edited by Prof. Schele Dh Vere. WONDERS OF ENGRAVING. (34 Illustrations.) For specimen Illustration, see J>age 4. THE FIRST'SERIES OF ^Jp IKKusl^rfll^pb Itifiparg of Wonbprs Comprises Twenty Volumes, containing over 1,000 Beautiful Illustrations, rhese twenty volumes in cloth, or in half roan, gilt top, are furnished in a black walnut ca.st> for $30.00 (the case gratis), or they may be bought singly or in libraries, classified ac- cording to their subjects as below, each i vol. i2mo. Price per vol. $1.50. WONDERS OF NATURE. THE HUMAN BODY . THE SUBLIME IN NATURE . INTELLIGENCE OF ANIMALS THUNDER AND LIGHTNING. BOTTOM OF THE SEA VHE HEAVENS . . . . 6 Vols in a neat box, $9. No. Illus. 43 WONDERS OF ART. ITALIAN ART EUROPEAN ART . ARCHITECTURE . GLASS-MAKING . W^ONDERS OF POMPEII EGYPT 3,300 YEARS AGO 6 Vols, in a neat box, tm Illus. . 28 II . 60 . 63 9'> WONDERS OF SCIENCE. No. Ill 1 HE SUN. By Guillemin . WONDERS OF HEAT OPTICAL WONDERS . WONDERS OF ACOUSTICS . 4 Vols, in a neat box, $6. ADyPNTijr.ES & EXPLOITS. No. Illus. WONDERFUL ESCAPES . . 26 BODILY STRENGTH & SKILL ^o BALLOON ASCENTS ... 30 GREAT HUNTS .... 22 4 Vols, in a neat box, $6. ^T" Any or all the volumes of the Illustrated Library of Wonders sent to any address, post or express charges paid, on receipt of the pnc?. Jt descriptive Catalogue of the Wonder Library, with specimen illustrations, sent to nny a'i