'Si '■''"■ 
 
New York 
 
 State College of Agriculture 
 
 At Cornell University 
 
 Ithaca, N. Y. 
 
 Library 
 
Cornell University Library 
 Q 181.J12 
 
 Nature study for the common schools, 
 
 3 1924 002 952 897 
 
The original of this book is in 
 the Cornell University Library. 
 
 There are no known copyright restrictions in 
 the United States on the use of the text. 
 
 http://www.archive.org/details/cu31924002952897 
 
NATURE STUDY 
 
 FOR 
 
 THE COMMON SCHOOLS 
 
 BY 
 
 WILBUR S. JACKMAN, A. B. 
 
 TEACHER OF NATURAL SCIENCE, COOK COUNTY NORMAL SCHOOL, 
 CHICAGO, ILL. 
 
 NEW YORK 
 HENRY HOLT AND COMPANY 
 
Copyright, 1 8gx, 
 
 BY 
 
 WILBUR S. JACKMAN. 
 
^ftje ^ominxan McUool ^eajctuet; 
 
 THIS BOOK IS RESPECTFULLY DEDICATED BY 
 
 THE AUTHOR. 
 
PREFACE, 
 
 In the preparation of this book it has been the aim 
 to furnish a guide for teachers in the common schools 
 who wish their pupils to pursue an adequate and sym- 
 metrical course in Natural Science. Science teaching for 
 a few years past has bfeen gradually working itself down- 
 ward from- the colleges and high schools into those of 
 lower grades, biit, in most cases, the plans followed, 
 while fairly well adapted to the demands of advanced 
 pupils, have been but poorly fitted to the needs of begin- 
 ners. The plan here adopted is based upon what is be- 
 lieved to be the proper interpretation of the character of 
 the knowledge that the child can acquire. This knowl- 
 edge may be characterized ^s having grestt breadth but 
 little depth. The forces of nature impinge upon the 
 child from every side, and he responds at once to their 
 touch. Animal, plant, mineral, river, cloud, sunbeam, 
 mountain, physical and chemical changes are all matters 
 of equal and absorbing interest to him, and if left to 
 himself he will inquire as freely about one as another. 
 ' It is a mistaken idea that the child's interest is best 
 aroused by a " thorough " study of a few living things, 
 animal or plant, such as form the chief stock in trade in 
 many school-rooms. This specialization in elementary 
 grades must result in one or both of two things : either 
 the whole subject will become distasteful, or, at least, 
 
IV 
 
 PREFACE. 
 
 tiresome to the pupil, or his eyes will be closed to other 
 sides of nature equally interesting arid important. In 
 either case the subject studied will be but poorly under- 
 stood, because it has been isolated and its relations to 
 other subjects not clearly seen. An attempt has here 
 been made to get rid of the old linear arrangement of 
 the different divisions of natural science in a- course of 
 study in which the various subjects were made to follow 
 one another in an unnatural sequence. 
 
 The Unity of Science, with Life the central study, is the 
 basal idea upcrti which the work has been prepared. 
 Life, in the final analysis the individual's own life, is the 
 center of all study, and the value of any particular sub- 
 ject must be ultimately estimated by what it contributes 
 toward a better comprehension of it. This idea is em- 
 bodied in the appended synopsis of the entire subject. 
 
 Life 
 
 An 
 
 and^its 
 
 Expression ■ 
 
 Phenomena, 
 
 of 
 
 
 » 
 
 
 
 Energy 
 
 acting 
 through 
 
 Matter 
 
 Animal , 
 
 y Biology. 
 
 Plant 
 
 
 Zoology ) 
 Botany 
 Physics. 
 Chemistry. 
 
 !^ \ and ^'S \ Meteorology. 
 
 Astronomy, 
 
 Geography. 
 
 Geology. 
 
 \ Mineralogy. 
 
 It is not intended that the Science work outlined in the 
 following pages should be incidental, as ordinarily under- 
 stood, but that it shall be assigned a regular place in the 
 daily programme with other lessons. Regularity and fre- 
 quency of the exercises are of primary importance, while 
 the absolute amount of time devoted to them is secondary. 
 For a scheme of twenty exercises for a month the follow- 
 
PREFACE. V 
 
 ing division of the work is suggested : Zoology and 
 Botany, one lesson each week; Physics, Meteorology, 
 Astronomy, Geography, and Geology, one lesson each in 
 two weeks ; Chemistry and Mineralogy, one lesson each 
 a month. This order and division should be modified so 
 as to suit the character of the season, the grade, and the 
 various minor conditions peculiar to the circumstances of 
 the different teachers. By "lessons" it is meant that at 
 regular times in general exercises the results of the pupils' 
 observations will be gathered up and discussed and sys- 
 tematically arranged, and that at such times general ex- 
 periments may be performed or other observations made. 
 
 It may be thought that the results thus obtained will 
 be disconnected and superficial ; but many thoughtful 
 teachers who have tried the plan find the reverse to be 
 true, and that the reasoning powers of the pupils are 
 greatly quickened by their having at hand a large amount 
 of data gathered in a varied experience. If the one les- 
 son be of a. fruitful, stiiiijilatiig character, the pupils will 
 be observant and thoughtful until the time for the next 
 one arrives, which is all that is necessary to secure a 
 healthy mind development. 
 
 The work assigned to each month has been selected 
 because it will be most natural for the pupils in its proper 
 season, and in many cases it can be better understood, 
 and because at such times it is most convenient for the 
 teacher to secure appropriate material and conditions. 
 The division into different subjects is for the teacher's 
 convenience alone, it not being necessary for the pupils 
 to know even the approximate limitations of the subjects 
 between which hard and fast lines do not exist. 
 
 It must not for a moment be supposed that it is the 
 design for the teacher and pupils to finish the outlines 
 
VI PREFACE.. 
 
 prepared for any month or season. Science cannot be 
 finished in a month, nor in a lifetime, though the study of 
 it is too often most unfortunately finished by those teach- 
 ers who put an end to their pupils' desire to know 
 more about it. Certain lines have here been indicated, 
 along which ft is hoped that teachers may be able to 
 awaken and foster observation and thought, and at the 
 same time bring their pupils into fuller knowledge of 
 themselves and of their duties and relations to the world 
 around them. 
 
 The author desires to acknowledge his indebtedness for 
 much that is contained in the chapter on Expression to 
 the discussions which, under the: leadersliip of Colonel 
 F. W.: Parker, have made the ever-to-be-remembered 
 Monday evening Faculty meetings an unfailing source of 
 inspiration in all the work. 
 
 W. S. J. 
 
 Cook County Normal School, 
 
 Chicago, III., July i, 1891. 
 
NATURAL SCIENCE 
 FOR THE COMMON SCHOOLS. 
 
 INTRODUCTORY. 
 
 CHAPTER I. 
 
 THE MOTIVE. 
 
 It is of primary importance that the teacher who 
 seeks to introduce elementary science into the common 
 schools should make earnest study of the motive for do- 
 ing such work, and at the same time carefully formulate 
 intelligent methods for conducting it. It is under no 
 other conditions that the undertaking can be successfully 
 carried out, and, rather than attempt to do it blindly, 
 the task had better not be begun. 
 
 Natural science, concerned largely with the earth and 
 the living things it supports, affords the earliest and the 
 only direct means of introducing the child to his earthly 
 habitation. The life, health, and happiness of the in- 
 dividual is dependent upon his knowledge of the things 
 about him, and upon the understanding that he has of 
 their relations to each other and to himself. This knowl- 
 edge and apprehension of relations can only be acquired 
 by actual personal contact and experience with the things 
 and forces which make up and govern the universe. It 
 is true, the concept of a tree, gained froni the study of 
 the object itself, furnishesa starting point for a great deal 
 
2 NATURE STUDY. 
 
 of knowledge about trees in general, but that knowledge 
 is weak and inaccurate so far as the objects described 
 differ from that upon which the original concept is 
 based. The avenues through which the elements of the 
 concept must be gained are the senses, and therefore 
 the very essence of science work, upon whatever 
 plan conducted, must be direct, individual observation. 
 The material selected should be of such character as will 
 provide the mind with the most useful concepts. It will 
 be a matter of profound surprise to any one who will 
 take the trouble to investigate, to find how vague the 
 ideas of very commonplace things are in the minds of 
 many persons who are to be classed as intelligent and 
 even educated. Critics make merry over patient 
 endeavor to get pupils to do simple, easy things, 
 which they say are self-evident from the very dawn of 
 intelligence. Yet, the teacher will likely make a great 
 mistake if he takes very many of even the simplest con- 
 ceptions for grantedr It is a proposition needing no 
 demonstration that without these conceptions the reason- 
 ing faculty is powerless. 
 
 But true science work does not stop with mere seeing, 
 hearing, or feeling ; it not only furnishes a mental pic- 
 ture as a basis for reasoning, but it includes an interpre- 
 tation of what has been received through the senses. A 
 child and a goat may see the same thing, with the ad- 
 vantage of vision on the side of the goat ; but the latter 
 has no power to interpret what he sees, and is, therefore, 
 essentially non-scientific. In these early interpreta- 
 tions, lie the beginnings of the reasoning power, and with 
 its development comes self-reliance, independence of 
 thought, and a general strength of character which 
 marks a man among men. If a pupil be permitted 
 
THE MOTtve. 3 
 
 to carefully examine an object or a set of conditions, 
 and then be required to interpret what he sees, he is 
 from that moment ever after stronger than he was 
 b,efore. By that act, no matter how trivial, he begins 
 the great work of self-emancipation from the rule of 
 chance in so far as his interpretation has taught him 
 how the forces about him may be resisted, guided, and 
 controlled. 
 
 A'great work is to be done by inculcating living truth ; 
 but one equally important must be accomplished in 
 rooting out the influence of inherited errors. We 
 are not yet free from the . dominion of some super- 
 stitions as dark as any that ever existed. There is a 
 pressing need that the pupils be taught the truth about 
 the laws of nature and about common things that, at 
 least, they may not hereafter become the prey of the 
 unscrupulous. It is by no means uncommon to find an 
 advertisement of goodly proportions in daily papers, 
 
 setting forth that Madame , seventh daughter 
 
 of the seventh son, of necessity possessing occult power, 
 will, for a very small consideration, reveal much that is of 
 the highest importance to those in trouble, or otherwise 
 in need of such information. Such advertisements throw 
 strong side lights upon the present condition of the 
 popular mind, from a scientific point of view. Properly 
 interpreted, they mean that there are enough people 
 about us, so grossly ignorant of natural laws, that they 
 are the willing victims of a base fraud -to the extent of 
 supporting it in idleness at a handsome income, no doubt, 
 after paying all expenses for advertisements and an 
 establishment. But there is a larger class, perhaps, who 
 will only plant their seeds in the light of the moon, who 
 never begin anything on Friday, who dislike to be called 
 
4 kATVRE STUDY. ^ 
 
 number thirteen, and for whom a broken looking-glass 
 bodes disaster. 
 
 The people of the present time over fifty years of age, 
 who are absolutely free from such superstition, are the 
 exception. And still further interpreting, in the most 
 narrow manner, Pope's dictum, " The proper study of 
 mankind is man," pupils are actually taught to despise 
 a great many creatures and 'things which probably play 
 as important a part in the economy of the universe as do 
 the lords of creation. In these times of indiscriminate 
 pistol practice, nothing should be done which would tend 
 to lower the value of human life in the estimation of the 
 pupils ; but, in view of the ruthless and utterly pur- 
 poseless slaughter of the harmless members of the so- 
 called brute creation, the regard for human life seems 
 almost exaggerated. The average boy may be trac"ked 
 through the woods by the blood of the innocent creatures 
 he destroysr-a wanton destruction, based upon utter 
 ignorance of the function of these creatures and upon 
 groundless fears. From earliest childhood the notion is 
 itnplanted that in most living things about him, of the 
 brute creation, there is a hidden danger to his life or 
 comfort. Then through the maxim that self-preserva- 
 tion is the first law of nature, he logically reaches his 
 watchword, "kill." But if the truth were known, it is 
 hardly an exaggeration to say that not one person in a 
 thousand meets one thing in a thousand in the whole 
 course of a year, which would do him the least harm. 
 On the other hand, how many that are thoughtlessly 
 destroyed do incalculable good ? The notion, too, 
 that fear of certain things and horror of others is in- 
 stinctive and natural, is totally false, as any one may 
 prove for himself by observing a little child. He is 
 
TH& MOTIVE. S 
 
 as much interested in a snake as in a kitten, and fondles 
 one as freely as the other. 
 
 Ignorance of natural law is no less marked in its 
 effects upon us than ignorance of living objects. Too 
 many people still see in the lowering thunder cloud 
 little else than the chariot of a great avenger ; who re- 
 gard the lightning's stroke, the flood, and the fire chiefly 
 as expressions of vindictive power. Speed the happy 
 day when the general diffusion of scientific knowledge 
 shall remove from the mind of man the last vestige of 
 that feeling that he is being hunted off the face of the 
 earth, the victim of a mighty wrath. Then, for the first 
 time in the evolution of the race, will he be in the perfect 
 attitude of a true student of nature. 
 
 While the motives for instruction in science here given 
 may seem valid and of sufficient importance to warrant a 
 place for it in the common schools, there, is yet one 
 thing lacking. The " Enacting Clause,'' to give positive 
 character and vitality to the work, must be added. " For 
 what good " must have an answer in a motive, which 
 makes science instruction something more than a merely 
 pleasant or fashionable pastime for both pupil and 
 teacher. The true incentive will make scientific 
 knowledge a necessity, and will do more than rouse 
 simply a kind of adventitious interest in the works of 
 nature. If it go no farther than this, then the teacher 
 will be utterly unable to reach the pupil who says by 
 word and action that he cares nothing for nature. 
 The final motive for the study of science is to bring 
 the pupil by degrees to a strong personal realization that 
 he is the focus of innumerable forcesabout him which so 
 bear upon him, and so limit his life and comfort, as to 
 render the knowledge of how they may be resisted, 
 
6 NATURE STUDY. 
 
 \ guided, and controlled, an absolute necessity. Life, ulti- 
 mately his own life, is the great center of all his interest 
 in the world ; and this tnotive will co-ordinate his interest 
 in nature exactly with his interest in his own existence. 
 This will give him life in the broadest and best sense, 
 which is the ultimate aim of all education. Thus science 
 instruction takes its place in the common schools with a 
 motive at once pure and beneficent, and with an irre-. 
 sistible appeal to all to become life-long students. 
 Many a boy who little cares whether, by the laws of 
 gravitation, a stone is pulled downward or pushed up- 
 ward, will become interested intensely, whenhe realizes 
 that he is. under its constant operation until it finally 
 pulls him downward into his grave. The mechanics of 
 the lever is only so much "stuff and nonsense " to him, 
 until he finds that this knowledge will render possible an 
 economy of his energy, and thereby imniensely prolong 
 his mortal existence. In short, all phenomena of earth 
 
 \ and air are pregnant with the deepest interest when he 
 finds himself threatened through his ignorance and his 
 
 \ inability to interpret them. When we for a moment con- 
 sider how important this knowledge is, and how little of 
 what we possess was oJDtained in the schools, need we be 
 amazed to find that the average duration of human life 
 is but one-third of its possible length ? 
 
 No one has more clearly shown this point than Prof. 
 Huxley, who says : " Suppose it were perfectly certain 
 that the life and fortune of every one of us would, one 
 day or other, depend upon his winning or losing a 
 game of chess. Don't you think that we should all con- 
 sider it to be a primary duty to learn at least the names 
 and moves of the pieces ; to have a notion of a gambit, 
 and a keen eye for all the means of giving and getting 
 
THE MOTIVE. , 7 
 
 out of check ? Do you not think that we should look 
 with disapprobation, amounting to scorn, upon the father 
 who. allowed his son, or the state which allowed its mem- 
 bers, to grow up without knowing a pawn from a knight ? 
 Yet it is a very plain and elementary truth that the life, 
 fortune, and the happiness of every one of us, and more 
 or less of those who are connected with us, do depend 
 upon our knowing something of the rules of a game in- 
 finitely more difficult and complicated than chess. It is 
 a game which has been played for untold ages, every 
 man and every woman of us being one of the two players 
 in a game of his or her own. The chess-board is the 
 world, the pieces are the phenomena of the universe, the 
 rules of the game are what we call the laws of nature. 
 The player on the other side is hidden from us. We 
 know that his play is always fair, just, and patient. But 
 also we know to our cost that he never overlooks a mis- 
 take or makes the smallest allowance for ignorance. 
 To the man who plays well, the highest stakes are paid 
 with that sort of overflowing generosity with which the 
 strong shows delight in strength, and one who plays ill 
 is checkmated, without haste, but without remorse. My 
 metaphor will remind some of you of the famous picture 
 in which Retzsch has depicted Satan playing at chess 
 with a man for his soul. Substitute for the mocking 
 fiend in that picture a calm, strong angel, who is playing 
 for love, as we say, and would rather lose than win, and 
 I should accept it as an image of human life.'' 
 
o NATURE STUDY. 
 
 CHAPTER II. 
 
 PRINCIPLES. 
 
 It is obvious that the methods of instruction adopted 
 by the teacher in any subject should be those which suit 
 themselves to the natural conditions of the pupil. The 
 proper clew which will enable the teacher to determine 
 upon the principles which must guide him in his methods 
 of instruction in elementary science, must come, there- 
 fore, from a close study of the child. The normal child 
 himself will tell by his actions what things appeal earliest 
 and most strongly to him, and will thus indicate to the 
 teacher the lines along which it is best to guide him. 
 The time has come for teachers when "a little child 
 shall lead them." 
 
 If it is perfectly safe to take the spontaneous develop- 
 ment of the child's mind under the influence of his 
 natural environment as a guide in instructing him, it is 
 necessary for the teacher to carefully study the child's 
 methods and to critically scan both the kind and the 
 character of the knowledge he acquires. With this in 
 mind, turn him loose for a time upon the world and give 
 him rein. He will- return by and by, in his realm a dis- 
 coverer and a conquerer. He will tell of the flowers 
 that he finds, in his pathway ; of the trees, and of the 
 birds which sing in their branches. He tells of the 
 shining pebble and sparkling sand beneath his feet, and 
 of the great clouds rolling through the heavens overhead. 
 He has found the tiny insect in its hidden home, and the 
 remotest star whose radiance strikes his eye. He has 
 watched the wonderful journey of the sun from the 
 earliest morning ray, till the last golden shaft at night, 
 
PRINCIPLES. 9 
 
 and feels anew his delight at the appearance of the silver 
 moon. He has been startled by the lightning's flash and 
 awed into silence by the roar of thunder. He has seen 
 the stream winding its way to the river, now peaceful, 
 and again as a roaring torrent tearing its banks and 
 building bars, and he has seen, the fog lifting itself from 
 the valleys. He. has been fanned by .the soft winds of 
 summer, and chilled by the blasts of winter. He has 
 tried to bathe himself in the glories of the rainbow and 
 ^^e has coveted the diamonds of the dew. He has been 
 drenched by the pelting rainstorm and he has rolled him- 
 self in the blanket of snow. He has witnessed ' that 
 great resurrection in spring-time, and has seen the living 
 world grow, mature, and die, almost as he rouses him- 
 self from slumber in the morning, and sinks to rest again 
 at night. He has tested his own strength and feels some- 
 thing of his own possibilities and limitations. In short, 
 the great universe of God has been spread before him 
 and he has scanned the whole as an open page. 
 
 This observation illustrates two important points — the 
 only ones, it may be said, necessary to consider, in for- 
 mulatirig a course of study. First, it gives a true idea of f 
 the scope of a child's observations, and second it indi- i 
 cates th« character of the knowledge he can acquire. It 
 is amazing to find what a field of observation is open 
 for a child but two years of age. Every nook and 
 corner of the house is explored and becomes part of the 
 known. He ranges through the door-yard, garden, 
 and farm, and learns the names of fruits, animals, and 
 places. He takes up everything with such avidity and so 
 rapidly that it would seem, if he could be kept growing 
 at the same rate until he has lived through the years al- 
 lotted to the common school course only, he would be a 
 
lo NATURE STUDY. 
 
 renowned scientist. That this marvelous interest does 
 flag, however, is painfully evident, and the question that 
 pressess itself home is. Who is reponsible for it ? Who, 
 indeed, can be but the teacher ? The child comes to 
 him with an expanding soul, even as all have felt 
 their souls expanding once, under the genial influ- 
 ences of nature,- and the school proceeds to deliber- 
 ately squeeze the life out of him with the same modes 
 of instruction which squeezed the life out of the gener- 
 ations before him. He comes to the teacher with his 
 eyes filled with a thousand pictures, but they are ignored, 
 and he is robbod of them one by one until at last the 
 beauty of this world fades from his sight and it is changed 
 to a vale of tears. ' In'the beginning of science instruc- 
 tion and to the end, the fact must be recognized that the 
 child stands at the center of the universe, and from first 
 to last is touched by everything in it. A complete and 
 symmetrical course of instruction must proceed outward 
 from this center though the phenomena, that surround 
 it. to the laws that lie beyond them. By such a course 
 only can the teacher hope to impress upon the pupil his 
 true relations to the things and forces about him. 
 
 It remains to make more specific inquiry as to how the 
 teacher shall proceed in order to attain this end. Turn 
 again to the child in direct contact with nature, and 
 look into the character of the knowledge he acquires. 
 If he tells about a flower, it will probably be something 
 of its color ; if about a bird, its song or its plumage ; if 
 about a pebble, its smoothness or roundness, and so on- 
 The character is unmistakable. It is all breadth and no 
 depth. 
 
 This interpretation of the action of the child-mind 
 meets with opposition because it seems to encourage su- 
 
PRWCIPLES. 1 1 
 
 perficiality. But the clew thus obtained from the child 
 himself gives unmistakable evidence as to the course the 
 teacher should pursue. It is a radical error to attempt 
 to make specialists of the pupils from the beginning. 
 Undue prominence given to any particular branch of 
 science in the common schools will lead to one-sided 
 development, and in the end to superficial work. Early 
 specialization leads inevitably to a certain linear arrange- 
 ment of the different branches of science which is 
 radically wrong in its conception and misleading and 
 confusing in its effects. 
 
 The arrangement of the subjects so that one shall, in turn, 
 succeed another in regular order (this not being the same 
 in any two schools), is a device which has done the most 
 to obscure the relations of the so-called branches of 
 science to each other and to the child. However neces- 
 sary such an arrangement may be for an advanced 
 course, in elementary work there is not the slightest 
 foundation for it, either in nature as it presents itself for 
 study, or in the conditions under which the child's mind 
 develops. Nor is it so important as many teachers sup- 
 pose to use the material afforded by any particular sub- 
 ject in a fixed order. In zoology, for example, it matters 
 not the least whether the child begins with a vertebrate 
 or an invertebrate, provided, in that particular thing 
 there is something which he wishes to study. In botany, 
 it matters not whether it be a fungus or a flower that 
 opens up this great kingdom of life to him. The mistake 
 made on this point by teachers is a fundamental one, and 
 it lies in supposing that those objects which are physically 
 near to the child are the only ones which have a psychic 
 nearness. A bright butterfly, or even an oyster, is much 
 nearer, psychically, to the child than a horse. 
 
t2 Nature stud v. 
 
 In disposing of this 'difficult question of arranging & 
 course of study and selecting suitable material, the 
 teacher must take his cue from nature and from his own 
 immediate surroundings. Science teaching indoors will 
 be vastly enhanced if it be supplemented and reinforced 
 by nature outside. The work should therefore be 
 planned to suit the changing and recurring seasons. 
 This is best because it is most natural, for the child is 
 fplaced in contact with nature under normal conditions, 
 and it is much more easy for the teacher and pupils to 
 obtain appropriate material. It is true, flowers may be 
 studied in winter time ; but to the child they are freaks, 
 and such a study is a distortion of the subject to his 
 mind, and it gives the teacher endless trouble. A study 
 of the plant, with its buds housed in their winter quar- 
 ters or with its seeds buried in frozen soil, is an appro- 
 priate subject for the season, and the supply of material 
 is natural and abundant. 
 
 The most serious obstacle in the way of science work 
 is the teacher's own lack of faith in his ability to do any- 
 thing useful or creditable. He should without hesitation 
 begin with the simple things around him, and grow with 
 the pupils. The crude and scanty appliances at hand, 
 well used, will open the way for better ones which will 
 surely come, for, in the end, the schools are not to suffer 
 from the want of any really good thing. 
 
EXPkEssior^. 13 
 
 CHAPTER III. 
 
 EXPRESSION. 
 
 The value of science work to the pupil is very greatly 
 enhanced by a complete and clear but concise expression. 
 Success in teaching the subject depends so largely upon 
 the teacher's judgment in using the appropriate modes of 
 expression at the proper stage of each particular kind of 
 work, that it becomes necessary to give the subject care- 
 ful attention. Teachers usually lay much stress upon 
 oral and written language ; but valuable as they may be, 
 they are inadequate to the demands which a study of 
 science makes upon the pupil for thought expression. 
 
 In order that the subject of expression may be under- 
 stood, it is necessary to consider it in its relation to the 
 means by which knowledge is gained. The various 
 modes of expression have a natural basis in the different 
 modes of study. By a mode of study is meant the means 
 and the process by which the mind receives data from 
 the world without. These modes may be included under 
 three heads, as follows : First, the study of the object ; ■ 
 second, the study of the object -by some means which 
 partially symbolize it, and third, the study by means 
 of symbols only. 
 
 The first mode mentioned, ordinarily termed direct 
 observation, may call into play any or all the senses, 
 touch, sight, hearing, taste, smell, and the muscular sense. 
 On the other hand, the real object under observation 
 presents all the attributes which can be cognized by the 
 mind. As a result, having received one or more elemen- 
 tary ideas through one or more of the senses, the mind 
 forms for itself a mental product which has the closest 
 
14 NATURE STUDV: 
 
 possible correspondence to the real object without. 
 This i^ the concept of the object. 
 
 The second mode of study makes use of pictures or 
 models, and to a limited extent of onomatopoetic words, 
 which cannot present directly all the attributes of the 
 real object, but may partially or wholly symbolize them. 
 Fewer of the senses may therefore be engaged in this, 
 and an imperfect concept is the necessary result. 
 
 The third mode of study is by means of hearing lan- 
 guage and reading, and consequently has to do with pure 
 symbols, only. Witli the exception of an occasional ono- 
 matopoetic word, before mentioned, whatever may have 
 been the origin of the symbols, they cannot now be 
 properly considered the attributes of any object. Their 
 function is simply to arouse in the mind certain activities 
 which form the concept from data already there. 
 
 In Its broad sense, the function of expression is to 
 produce an external thing which corresponds to the inter- 
 nal concept. The motive for expression is, subjective, 
 to intensify the thought of the one expressing it, and, 
 objective, to convey that thought toothers. Ethically 
 considered, expression may be either selfish or unselfish, 
 but there isnaturally no conflict between the two ends. 
 The more clearly defined and intense the thought be- 
 comes to the individual, the better can he convey it to 
 others, and there is a naturallyj^increasing desire to do so. 
 
 The mbdgs of expression have a natural correspon- 
 dence to the modes of study above outlined. They may 
 be included under the heads of gesture (including facial 
 expression, and attitude), music without words (including 
 the different tones of voice used in oral language, and 
 all moans and cries), making, modeling,- painting, draw- - 
 ing, oral language and written language. Each mode of 
 
EXPRESSION. 15 
 
 expression is peculiar in this, that it has a special function 
 of its own which cannot be perfectly performed by any 
 other one or more modes, though of course they do 
 supplement each other in almost every expression of 
 thought. 
 
 Closely associated with oral language, and from which 
 it may have arisen, are the two modes above classed 
 under gesture and music. The peculiar function of 
 these most subtle forms, the one appealing to the eye 
 and the other to the ear, is to convey directly from mind 
 to mind the idea of emotion. No other mode. has the 
 adequacy of either of these for this purpose. They each 
 convey an idea of something which is absolutely beyond 
 the domain of material representation. They place man 
 in immediate touch with his fellow-man, and form the 
 universal soul-bond of humanity — nay, of all animate 
 creation, for by them we even understand the brutes, 
 and they us and each other. Originally of objective 
 value chiefly, now all training in attitude, gesture, 
 and modulation of voice, takes advantage of the power 
 which these have to intensify the thought in the one 
 giving it expression. The data for the thoughts which 
 find expression by these means may be gathered throiTgh 
 anj or all of the senses. 
 
 The difificuUies encountered by the teacher in dealing 
 with these two modes are different from those which arise 
 in teaching any of the others. Whereas the others are more 
 or less arbjtrary, these are perfectly natural, and they are 
 the result, not of teaching, but of heredity. The difficulty 
 lies in co-ordinating the more arbitrary forms with them. 
 To make the word exactly correspond to the look, gesture, 
 or tone is the thing to be sought. The naturalness of 
 these modes is, unfortunately, very early lost, in most 
 
IS NATURE STUDY. 
 
 cases through a soul-consuming self-consciousness, and it 
 is regained with the greatest difficulty. Upon its proper 
 co-ordination with these modes, the general intelligibility 
 of oral expression depends, and by them the teacher has 
 an almost exact measure of the intensity of the pupil's 
 thought and of his interest and comprehension of the 
 subject in hand. 
 
 Making is the most definite and complete mode of 
 expression where material representation is possible. 
 This is because the maker becomes acquainted not 
 only with the object in all of its parts and as a whole, 
 but also with the nature of the substances with which he 
 works. As it is only by a study of the real object 
 that all of its attributes appeal to the mind, so it is 
 only by making, that the exact external correspondence 
 to the concept of these can be reproduced. It is the 
 peculiar function of making to give this external corre- 
 spondence material form. It is the simplest and lowest 
 mode because there are no mental pictures involved that 
 do not have a concrete -basis in the material before the 
 maker. It is a universal mode because the idea, that of a 
 certain box, for example, will be expressed by all in the 
 same way. This allies it closely with the two preceding 
 forms. 
 
 The data for this mode of expression are gathered 
 through all of the senses, and it therefore follows that in 
 the outward material representation of the idea, each 
 sense may act as a corrective upon all of the others and 
 thus making becomes one of the easiest modes. Great 
 difficulties arise, however, due to the peculiar and various 
 properties of the materials employed, such as wood, stone, 
 iron, and glass. This is further enhanced by tlie inability 
 to properly estimate the value of solid angles and lines and 
 
EXPRESSION. 17 
 
 by the lack of skill necessary to form flat and curved 
 surfaces. 
 
 Science work offers great opportunities for this mode 
 pf expression. Throughout the whole of physics and 
 chemistry there, are almost nurnberless pieces of appa- 
 ratus and devices which should be made by the pupil. 
 The difiiculties peculiar to this mode are more than bal- 
 anced by the intense interest which the pupil always has 
 in, making something. It brings him to the joy of a new 
 creation in which he plays the r61e of creator, and, in the 
 cultivation of self-reliance, this can hardly be overesti- 
 mated. And when still further, as in the Sloyd, it is the 
 thought, " This is for some one I love — for father or 
 mother," that drives the plane or handsaw, it makes it, in 
 its reflex upon character, second to no other moral influ- 
 ence. 
 
 Modehng, in itself, has to do entirely with form, both 
 external and internal, and so far, it is identical with 
 making. As a mode of expression, though, it is differ- 
 entiated from making in regard to size. An object may 
 be modeled many times as large or small as that of which 
 it is intended to give the idea. The data for the model 
 are gathered through the senses of sight and touch, and 
 while, therefore, the judgment lacks some of the safe- 
 guards thrown around it in making, this is offset by the 
 fact that there is less of the complete idea to be expressed 
 by it. The difficulty to be overcome in modeling, as 
 in making, is in the estimation of solid angles and in 
 the formation of curves and plane surfaces. The mate- 
 rial used may be of such character as to reduce the diffi- 
 culty of its manipulation to the minimum. 
 
 The use of this mode in science work is varied. In 
 zoology, clay modeling may be used with great advantage 
 
I& NATURE STUDY. 
 
 in the study of the larger animals and in the study of the 
 skeleton. In botany, early study of roots, the various 
 forms of underground stems and fruits will necessitate 
 its use. In geography, geology, and mineralogy either^ 
 sand or clay may be used to show the relief of any given 
 area covered by an excursion or a field;lesson, and the 
 latter is specially fitted for showing rock strata, dip, and 
 forms of crystals. 
 
 Painting as a mode of expression is unique. |^Its peculiar 
 function is to give the idea of color — something which can- 
 not be even approximated by any other mode. It stands in 
 contrast with both making and modeling, because it is 
 primarily independent of volume, size, and substance. It 
 can, it is true, be made to suggest solidity of form after 
 the idea has been gained by other means. 
 
 The data for painting are gathered through the sense 
 of sight alone. The chief difficulty which besets the 
 judgment is due to the fact that there is no corrective sense; 
 if the eye fails to give the proper datum there is no other 
 means by which the mistake may be discovered. 
 
 In a large part of elementary science work the value 
 of painting can hardly be overestimated. Primary pu- 
 pils can tell far more with their brushes and colors, and 
 can tell it much better than they can with either tongue, 
 pen, or pencil. It will greatly enhance interest in the 
 study of birds, insects, fruits, flowers, leaves, and min- 
 erals. 
 
 In drawing, the chief thing to be expressed is outline, 
 not only of the whole, but, also that of the parts of an 
 object. This mode of expression, closely related to 
 painting on one side and to making and modeling on the 
 other, is independent of solidity of form and size. It is 
 allied to modeling and more remotely to making because 
 
EXPRESSION. 19 
 
 it deals with form, but only so far as it can be expressed 
 in outline without giving the idea primarily of volume. 
 The chief difficulty in cultivating this form of expression 
 with beginners lies in a lack of muscular control which 
 is necessary in drawing straight and curved lines, and in 
 the errors of judgment in the measurement of angles and 
 estimation of distances. The judgment is, in this form 
 of expression, dependent upon sight alone, and in tliis 
 respect it is allied to painting. 
 
 In science, drawing may be employed with great ad- 
 vantage in all subjects. Its earliest application is found 
 in the representation of apparatus used in physics and 
 chemistry, and all material where sharpness of outline 
 and detail of structure are required. 
 
 Between written language and the forms of expression 
 already considered, there is a wide difference. It is 
 wholly an arbitrary means of expressing thought, and 
 can intensify it subjectively only in this way : by means 
 of the device of which this mode of expression makes use 
 —that is the written sentence — a relation is expressed 
 which by the aid of this visible sign, is held more steadily 
 before the mind as an object of study. In function, it is 
 distinguished from the preceding modes by the fact that 
 certain relations may be directly expressed by it which lie 
 wholly bej'ond their domain. "Man should help his 
 fellow-man," expresses an obligation ; by the written 
 sentence, this idea is conveyed to others — something 
 "which could not be accomplished by any other single 
 mode. 
 
 The judgment expressed by the written sentence rests 
 upon data that may be gathered through every avenue 
 of sense. The chief difficulty is in the lack of muscular 
 control which is necessary to guide the pen, and in mak- 
 
20 NATURE STUDY. 
 
 ing the arbitrary association of certain letters with defin- 
 ite sounds which the former represents. 
 
 In science work, written language is of universal appli- 
 cation as a mode of expression. Too often, however, 
 its use is demanded when some other mode would be 
 more appropriate. 
 
 Cldsely allied to written expression is that by oral 
 language. It is related to written language, and differs 
 from all the other modes because ideas can be ex.pressed 
 by it which are beyond the reach of material representa- 
 tion by any other single form. Its peculiarity is found in 
 the tone of voice which, independently of the words ut- 
 tered, intensifies or diminishes the strength and clearness 
 of expression. In developing this form, the chief obstacle 
 is encountered in the difficulty which the child finds in 
 associating his thoughts and feelings with the jingle of 
 sounds which represents them in the spoken sentence, 
 and in the training of the. organs concerned in articulate 
 speech. 
 
 All of the senses may be concerned in completing the 
 thought which finds expression in oral language. Prac- 
 tice with this form of expression is frequently pushed 
 too far. Teachers are naturally ambitious to hear 
 their pupils talk, and feel disappointed when they fail 
 to so express themselves. Yet with children, that 
 it is wholly inadequate, sometimes, for the full 
 expression of the thought, is a fact which should be 
 recognized. 
 
 While expression may admit of the foregoing analysis, 
 and it would seem that each mode has its own peculiar 
 function, it will be observed that usually two or more 
 may be combined in the expression of any thought, the 
 
EXPRESSION. 21 
 
 fullness and clearness of which are greatly enhanced 
 thereby. 
 
 It remains now to consider the natural order of their ■ 
 development. The different modes are not developed ! 
 entirely seriatim, but something of the serial order is en- ; 
 forced, in practice, by certain difficulties before mentioned 
 in connection with each. Expression is primarily de- 
 pendent upon external stimuli, and it follows that the 
 mode will be determined somewhat by the character of 
 the stimulus of which the organism is susceptible, and 
 for a like reason, the order of development will also be 
 somewhat fixed. 
 
 The earliest kind of stimuli which the child receives 
 are those producing bodily pleasure or pain, and the ex- 
 pression corresponds. The smile of the young babe in 
 its cradle is the earliest expression of that light which 
 through its new-born soul is destined, it may be, to make 
 luminous the dark places of earth. The frown flitting 
 like a shadow across its smooth brow is the earliest 
 prophecy of a spirit which is born, perhaps, to crush a 
 tyrant and emancipate a people. This mode, coming to 
 the child by heredity alone, has no conscious relation 
 at this time to the thought or feeling beneath it. 
 
 The next stimuli are received through the sense of 
 sight, derived from the mere presence of an object 
 and through the sense of touch, from its smoothness, 
 roughness, hardness, or softness and so on. The appro- 
 priate form of expression is by oral sounds leading 
 to articulate speech. After the mere presence of the 
 object is made known the next stimulus comes from 
 its most striking peculiarity. This is most frequently 
 received through the sense of sight, and comes usually 
 
22 NATURE STUDY. 
 
 from the color of the object. The, natural and appro- 
 priate form of expression is by use of brush and paint in 
 color work. The -pupil constantly compares the color he 
 uses with that of the object, and thus supplies the only 
 corrective to his judgment possible in this case. Associ- 
 ated closely with the idea of color is that of form. This 
 demand for an additional mode of expression is met by 
 exercises in modeling. This order, however, should often 
 be reversed, since peculiarity of form is sometimes more 
 conspicuous than brilliancy of color. 
 
 Developing considerably later than the ideas of color 
 and form is the idea of the outline of an object. The 
 natural expression for this is by drawing. Observation 
 confirms the fact that drawing with the pencil should not 
 begin much below the fourth grade. Previous to that it 
 may be practiced on the black-board in much broader 
 outlines and with less details than that required by the 
 pencil. This is not only because detail of figure does not 
 appear early to the pupil, but because his muscles are not 
 yet sufficiently under control. The arm moves the hand 
 chiefly from the shoulder ; individual muscles that move 
 the hand and fingers, absolutely necessary to fineness of 
 detail, are not yet separated one from another in their 
 functions. This difficulty is rapidly and completely 
 overcome by giving opportunities for blackboard draw- 
 ing when the full arm may at first be used in drawing 
 large-sized figures. 
 
 Making as a mode of expression may be commenced 
 very early, but the difficulties, arising from a lack of 
 knowledge respecting the nature of the materials, some- 
 what limit its range. Its use is further diminished by the 
 fact that many things studied cannot be made. This is 
 offset by the intensely practical character of the work- 
 
EXPRESSION. 23 
 
 There may be those who do not wish to paint, who can- 
 not draw, who fear to speak, or are too lazy to write, but 
 a pupil is rarely to be found who will not be interested 
 in making something. Most boys are in a continual 
 state of perplexity in trying to decide whether they will 
 be blacksmiths, carpenters, or shoemakers when they 
 grow up, and, for all such, making is the mode of expres- 
 sion ^ar excellence. 
 
 The development of expression by means c f written lan- 
 guage should be coincident with that of the other modes. 
 Through its peculiar function, it acts as a corrective and 
 check upon all of the others. It is very important that it 
 should stand in proper relation as to amount with the 
 other modes and to the actual demand for it. Teachers 
 frequently err by trying to force their pupils to write be- 
 yond what they really have to express. Some pupils ap- 
 pear to talk well, but write poorly ; yet it may be that the 
 sum total of all their "talk " actually expresses no more 
 titan the little they write. Again, too high an estimate 
 is often placed upon what the pupil really sees, and con- 
 sequently there is a feeling of disappointment at the 
 amount of the written work. Rationally employed, written = 
 expression is the most valuable adjunct to science work. 
 
 Although there seems to be a somewhat definite order 
 of development for the different modes of expression, yet 
 when once properly begun they should all be carried 
 forward in due proportion throughout the entire course. 
 If faithfully done, the so-called crudities and blotches of 
 the first grade will become tasteful products in the eighth. 
 
 The subject matter in science work presents itself 
 broadly under three heads: the study oi function, the study 
 of form, and the study of the mutual relations between 
 function and form. These divisions at once suggest to 
 
24 NATlfRE STUDY. 
 
 the thoughtful teacher a proper grouping of the modes 
 of expression. Evidently, those which best accompany 
 the study of function are oral language and written lan- 
 guage, and to a less important extent what has been in- 
 cluded under gesture. The other modes are not barred, 
 however, since one may, by a drawing, or in a clay model, 
 show how a squirrel holds a nut; but they are hardly to 
 be considered the initial modes of expression for such a 
 fact. 
 
 In the study of form almost any of the remaining 
 modes are more appropriate in the beginning than either 
 oral or written language. The particular form mus't be 
 determined by the one who makes the study — not by the 
 teacher. It is a fundamental mistake for a teacher to 
 say to his class, "We will model this," or "We will paint 
 that," or " We will draw the other." The substance of 
 the real question which should be proposed is, " What 
 do you see about this, or what can you find out about it, 
 and how will you tell it ? " When the teacher dictates 
 "Draw," " Paint," or " Model," he must run the risk 
 either of telling the pupil to represent what he does not 
 see or understand, or else he is forced into the contra- 
 dictory position of pointing out to him the very thing he 
 should discover for himself in order that he may repre- 
 sent it. This logically and actually destroys the real 
 point of the lesson, so far as science is concerned, and 
 reduces it to the level of a lesson in dead color and 
 dumb form. The pupil cannot express what he does not 
 see, and he must express what he does see through what 
 is to him the most natural and appropriate channel. For 
 example, in beginning the study, to ask a child to model 
 a brightly colored butterfly is to outrage his every sense 
 of fitness ; while to expect him to either paint or model 
 
EXPRESSION. 25 
 
 with great enthusiasm a long-legged, angular grasshopper, 
 is vanity of vanities. Full expression of thought will 
 naturally involve more than one mode, but there is de- 
 cidedly a right and a wrong place at which to begin. 
 
 The thoughts which come into the mind as it contem- 
 plates the mutual adaptations of the different parts of 
 nature to each other, and their relations to the whole 
 are, in their suggestions of infinite law, the loftiest that 
 can possess the human soul. The full expression of these 
 conceptions, involving the highest relations of man to 
 man, rises to the plane of fine art. Embalmed in verse, or 
 picture, or song, or chiseled stone, it will to future gen- 
 erations mirror forth the best and purest thoughts 6f thi« 
 age. 
 
PRACTICAL HINTS TO THE TEACHER. 
 
 In acting upon the suggestions in the following lessons, 
 it is essential that the teacher should unde'rstand the 
 spirit and purpose of the book. Recognizing the fact 
 that most teachers find themselves unprepared in the sub- 
 ject matter of elementary science, the book has been 
 written with a view to guiding them in their study so that 
 they may acquire some of the necessary knowledge by 
 actual work, and not with the intention of pouring out a 
 mass of so-called facts for them to memorize. Teachers 
 can never equip themselves for this work by reading 
 alone ; if that were possible, the requisite preparation 
 could be quickly made and, with a market well supplied 
 with interesting reading books, it would have been done 
 long ago. The main trouble is, not that the teacher's 
 mind is so barren of. facts, but that he lacks the scien- 
 tific habit and methods of study. These can only be ac- 
 quired by the exercise of the greatest patience, on the 
 teacher's part, in solving for himself some of the simple 
 problems presented so profusely by nature on every 
 hand. Under every division of the subject it has been the 
 aim to present two or three, sometimes more, leading 
 topics which the teacher should assist the pupils to work 
 out to the limits of their capacity by careful observation. 
 Every recitation in the school-room must be preceded by 
 lessons in actual 'observations, enough of which must be de- 
 manded from every pupil to give him a basis for his reason- 
 
 26 
 
PRACTICAL HINTS TO THE TEACHER. 27 
 
 ing. A most pernicious habit, and one very easily ac- 
 quired, is that of asking a pupil a question which Will start 
 him to guessing, thus deceiving himself into the belief that 
 he is actually reasoning. As a mere " Question and An- 
 swer Book," this book must inevitably fail, since that is at 
 utter variance with its purpose. The interrogative rather 
 than the declarative form has been adopted because it has 
 been found a little easier, by the former means, to carry the 
 thread of a thought through several suggestions. In 
 somecases one question suggests the thought of a topic ; 
 in others several questions are asked for the same purpose. 
 
 The teacher's ingenuity will be continually taxed to 
 furnish new devices adapted to the correct development 
 of a topic, which will also be properly subject to his own 
 peculiar circumstances and conditions. The latter are 
 not the same for any two teachers ; and the fact that this 
 will modify the treatment of any question is one that, first 
 of all, rnust be recognized and acted upon. 
 
 In approximating what the teacher should have in mind 
 in the preparation for each lesson to be given, the follow- 
 ing outline is submitted as a guide : 
 
 I. Plan for each Lesson. 
 A. Knowledge of Subject-Matter. 
 
 1. By direct observation. 
 
 {a) What can be seen in a field-lesson ? 
 
 {b) What can be collected by individual pupils ? 
 
 (c) What can the pupils make ? 
 
 2. What reading belongs legitimately to the prep- 
 aration ? 
 
 3. The adaptation to the pupils' and teachers' 
 
 conditions. 
 
 4. TI)e adaptation to the age and capabilities of 
 
 the pupils, i. e., to the grade. 
 
,28 NATURE STUDY. 
 
 S. What is the length of time which should be de- 
 voted to the preparation of the lesson ? 
 
 B. What modes of expression should be used ? 
 
 1. Oral language ? \ ^^^^ suggestive reading ? 
 
 2. Written language ? ) 
 
 3. Painting. 
 
 4. Modeling. 
 
 5. Drawing. 
 
 6. Making. 
 
 C. How is the lesson related to other subjects ? 
 
 1. Reading. 
 
 2. Number. 
 
 3. History and literature. 
 
 4. Language. 
 
 II. Hints to be observeh in giving the lesson ? 
 
 1. Have a reason clearly in mind for giving every 
 lesson. Seek for' this in the relation of the sub- 
 ject to the child. 
 
 2. Have a reason clearly in mind for the way in 
 
 which the lesson is presented. Seek for this 
 in a study of the laws which govern the growth 
 of the child's mind. 
 
 3. Plan only for such work as the pupils can do 
 
 for themselves, or, at least, take the leading 
 part in doing. 
 
 4. Place the -child directly in contact with nature 
 
 under normal conditions. 
 
 5. Begin with something which is really a part of 
 
 the pupil's experience — not with something 
 which you have to tell him. 
 
 6. Accept, as good, only such results as indicate 
 
 honesty of purpose and growth of mind. 
 
 7. Be faithful, and bide your time. 
 
Each season of the year has its own peculiar influence 
 upon living things, animal and plant. It is therefore 
 most convenient and certainly most interesting to study 
 each phase of life in the appropriate season, inasmuch as 
 one may then more easily trace the various phenomena 
 observed in living things to the forces in nature which 
 cause them. As the sun rises later and later, and sets 
 earlier, sinking still lower in the southern sky, and the 
 air now and then steals down upqn us with ah edge ac- 
 quired in northern snow-fields, animal creation takes the 
 hint and prepares for the inevitable ahd impendingchange. 
 The birds, the young ones that have never seen a flake of 
 snow, as well as the veterans of experience, in good time 
 gather themselves together, and within a few hours are 
 safe in another zone. Their luckless relatives, the rep- 
 tiles, appear with less and less frequency, and, finally, in 
 the lowest depths of their burrows give themselves up to 
 a stupor that seems more like death than sleep. The 
 winged insect hosts, battered and bedraggled, demoralized 
 by the gayeties of the season, until mere wrecks of their 
 former selves, for most part stiffen and die where they 
 are, rather than give up one moment of present pleasure 
 to thoughts for the future, or desert the fields that may 
 have seemed to them to promise endless enjoyment. 
 Others, apparently as much by chance as through design, 
 are saved from such fate by finding a lodgment in cracks 
 in old walls, in decaying logs, under §tones, and in holes 
 
3° NATURE STUDY. [September 
 
 in the ground. Other creatures, too plucky to leave, and 
 refusing to waste the winter in sleep, seek to cut down 
 living expenses in the time of dearth by taking on an 
 extra thickness of fur or hair, and by packing away great 
 layers of fat in times of plenty. In the streams the 
 changes are not less "marked. Chilled, and deprived of 
 their insect food, the fishes seek the bottom and hide in 
 recesses among the rocks. The "craws " withdraw them- 
 selves into their dens in the mingled sand and gravel, 
 while the tadpoles wriggle themselves under leaves and 
 grass on the sides and in the bottom of the ponds, and 
 for a time their froggish ambition is stayed. Nor are 
 these influences unfelt among human kind. Despite the 
 fact that our natural appetites are becoming somewhat 
 depraved by Ihe fruits and various vegetables which 
 modern means of rapid transit make possible for us in 
 January, we still are in a measure moved by instincts 
 simila;: to those which control our humble brethren, the 
 brutes. The gradual change in color, texture, and thick- 
 ness of clothing, and the modification in our appetites, 
 are signs the youngest school-child may note, and which 
 he will be interested to understand. These changes, in 
 the total amounting to a revolution in a living creature's 
 mode of life, take place every year so silently and 
 almost imperceptibly as to scarcely attract attention of 
 people in ge'neral ; nor does even the keenest observer 
 yet fully understand the causes by which they have been' 
 wrought. To lead to a careful study of these phenomena, 
 in which we ourselves are involved more deeply than might 
 at first be suspected, by teaching the child to live in close 
 and loving communion with nature about him, is the 
 highest duty of the teacher. Not by set lessons in the 
 recitation-room, nor by dissections in the laboratory 
 
September] ZOOLOGY. 3* 
 
 alone, can this be accomplished ; before these can reveal 
 the depths of their meaning he must study Life in at 
 least some of its myriad forms, and know something of 
 the forces that produce it, and conditions under which 
 it exists. 
 
 The teacher should select from the following topics a 
 few of those which are best suited to the conditions for 
 study that environ the pupils. A thicket, or even a single 
 tree, will generally enable the pupils to study the topics 
 on birds. 
 
 To collect insects, the pupils should be provided with 
 small nets-. Make these by bending a wire, about No. 8 
 or No. g, into a hoop six inches in diameter, and then 
 twisting -the ends together for two or three inches to form 
 a handle. This may be thrust into a hole made in the 
 end of an old broom-stick for a longer handle, if desired. 
 Make the net about eighteen inches deep, using mosquito- 
 netting or cheese-cloth. A little practice will enable the 
 pupils to get the insect and transfer it from the net to the 
 poison bottle (see Zoology for April, under Insects) with- 
 out marring them. Collect not only those insects which 
 are to be seen flying about, but also those that may be 
 obtained by jarring the branches of a shrub or tree over 
 the open net. A great number may also be easily obtained 
 by placing in convenient places shallow vessels containing 
 sweetened water or vinegar. Naturalists sometimes smear 
 tree trunks with a mixture of beer and molasses for the 
 same purpose. 
 
 In the lower grades, one or two poison bottles will suf- 
 fice for each room. In the grammar grades each pupil 
 should be encouraged to place a poison bottle among the 
 material, which he should be expected to collect and keep 
 for his own use during the year. The primary pupils 
 
3 2 Mature study. [September 
 
 will make far more use of the living insects than of the 
 dead ones ; but in the upper grades the study will natur- 
 ally be more detailed, and dead insects will be required. 
 In order to observe the work of earthworms in plug- 
 ging their burrows, select some place where they may 
 easily obtain leaves as they fall from the trees. It is 
 astonishing to find how many leaf-stalks are sometimes 
 pulled into one burrow. 
 
 BIRDS. 
 
 1. Are any birds nest-building or laying eggs at present ? 
 
 2. Can you distinguish the young from the old ? Which 
 parent do they most resemble ? 
 
 3. Do the young ones sing ? Are they still under the 
 care of the old birds after they have learned to fiy ? 
 
 4. Have any disappeared that were noticed during the 
 summer ? 
 
 The times of migration vary somewhat with the season, 
 within rather narrow limits. The birds should be watched 
 closely during this month and the next. 
 
 5. What influences can you discover at this season 
 which would cause the birds to migrate ? 
 
 INSECTS. 
 
 Nothing is more wonderful and interesting than the 
 great variety of insect life which may be studied at this 
 time. Some one has remarked that no region on the 
 globe has proven so inhospitable that some insect cannot 
 adapt itself to it ; nor has any other living creature suc- 
 ceeded in doing anything which the insects do not 
 imitate. 
 
 I. In what different places have you found insects ? 
 Look on the leaves of plants, under boards, logs, stones. 
 
September] ZOOLOGY. 33 
 
 etc., in old walls, in cellars, in cupboards, in the grass, on 
 the flowers, and in holes in the ground. 
 
 2. What are the chief differences between those that 
 spend their time in the open air and those that live under 
 stones, etc., as, for example, between butterflies and 
 beetles ? 
 
 3. What insects can you find that must have liquid 
 food ? What ones take solid food ? 
 
 4. Where do butterflies get their food ? Can you tell 
 certainly if they get it from flowers ? 
 
 5. Do they visit all kinds of floii^ers ? Is their food 
 solid of liquid ? 
 
 6. If the flower furnishes their food where is it 
 stored ? 
 
 7. What means does the butterfly employ in examining 
 the flower ? What does it do with the organ when not in 
 use ? 
 
 8. Does the butterfly store food for the future ? 
 
 9. How does it cling to the plant ? 
 
 ID. How does it dispose of its wings when at rest ? 
 
 11. Compare the upper and under surfaces of the 
 wings ; which render it more conspicuous. 
 
 12. Compare the color of butterflies with that of the 
 flowers they visit. 
 
 13. Hdw does the character of a butterfly's flight differ 
 from that of a bird ? How can you account for it ? 
 
 14. Is the peculiar flight of advantage or disadvantage 
 to it ? 
 
 15. Which has relatively the greater wing surface, the 
 butterfly or bird ? Which is the stronger flyer ? 
 
 16. Compare the fore and hind wings ; is the venation 
 the same in both ? Is it the same in the right and left 
 wings of the same pair ? 
 
34 NATURE STUDY. [September 
 
 17. Of what use are the legs? Compare and contrast 
 the different pairs. 
 
 18. Jn what order do they move when walking ? What 
 way do they bend at the joints ? Why are so many joints 
 needed ? 
 
 19. How are they arranged during flight ? 
 
 20. In what directions can the butterfly see you ap- 
 proach ? 
 
 2 1. Where are its eyes.? Can it turn its head? 
 
 22. Can it move its eyes without moving its head ? 
 
 23. Are the eyes sensitive ? Can yoii tell if it has the 
 sense of feeling ? 
 
 24. Has it the sense of smell and of hearipg ? Does it 
 make any sound ? Does it breathe ? 
 
 25. Are they social ? Do they build nests ? 
 
 26. Do they prefer sunlight or shade? Where do they 
 stay during the night ? 
 
 27. Are any eggs to be found at this season ? 
 
 28. Can you tell the male from the female ? Can you 
 see any reason for difference in color ? 
 
 Collect larvse (caterpillars) of different kinds and put 
 them in small boxes covered with light netting. Feed them 
 with the leaves of the plant upon which they were fourid. 
 
 In a way similar to the above outline, study grass- 
 hoppers, beetles, bees, and flies. 
 
 WORMS. 
 
 1. Note the manner in which worms plug their burrows 
 with leaves, etc. Do they eat them ? 
 
 2. Are the castings as numerous as in the summer 
 months ? 
 
 3. Can you find sticks or straws or other material that 
 has been drawn into their burrows during the season ? 
 
September] ZodLOGY. 35 
 
 TADPOLES. 
 
 1. In what stages of development are tadpoles to be 
 found ? 
 
 2. How do they breathe ? Look sharply for a small 
 hole on one side behind the mouth. Is it always on the 
 same side ? 
 
 3. What is their food ? 
 
 4. Do they venture out on the land ? 
 
 5. What enemies do they have ? 
 
 Books for Reference. Humboldt Library: Nos. 115 and 116. 
 No. 99, Nature Studies, chapter on Birds of Passage. No. 33, 
 Vignettes from Nature, chapters iv, xiv. No. 6^, Distribution of 
 Life. No. 92, Formation of Vegetable Mold. No. 26, The Evolu- 
 tionist at Large-, chapters x, xiv. 
 
Botany. 
 
 Introduce the lessons on plants with outdoor observa- 
 tions both with the class as a whole, if possible, and by 
 requiring individual work out of school hours. Indicate 
 the points of a lesson a sufificient length of time before 
 the recitation to give the pupils opportunity to make the 
 proper observations. Only a sriiallj)art of a plant's life- 
 history is revealed to us in a single month, but in many 
 cases the entire cycle of its life is shown in the course of 
 a year. The study should so proceed, therefore, as to re- 
 veal the' history as a connected whole when the year is 
 ended. Facts are rarely interesting unless seen in their 
 proper relations to each other. All drawings, paintings, 
 models in clay as far as possible, and written work, should 
 be carefully preserved so that additions may be made to 
 them in the different seasons. Sheets of paper of a size 
 8 J^xi I inches, both for writing- and drawing, will be found 
 convefiieTit for pupils of grammar-school age, while such 
 sheets cut in two crosswise will suit those in the primary 
 grades. These may be preserved by the pupil in a port- 
 folio, which he can easily construct for himself out of 
 cardboard. Drawing paper of the above-mentioned size 
 is large enough to admit of the representation of the most 
 prominent features of a plant's history. The drawings 
 and paintings made in the fall, of leaf, twig, fruit, etc., 
 should be so placed as to admit representations of the 
 germinating seed and young plant to be placed beside 
 them in the spring. Each sheet will thus present a whole, 
 
 3S 
 
September] BOTANY. 37 
 
 and the pupil will'almost unconsciously acquire the habit 
 of bringing all individual facts observed into proper rela- 
 tion with each other. 
 
 It will be a revelation to those botanists who are book- 
 bred, as well as to the children, to find that there is not a 
 day of the whole growing season ir^ which some seeds, be- 
 lated for one reason or another, are not trying to germ- 
 inate. Germination of seeds is associated mostly with 
 spring-time, because the seeds that do get a fair start at 
 that time are the ones that become so conspicuous later 
 in the season as to almost obscure the luckless ones that 
 failed to make an early beginning. Still, the latter do not 
 cease trying, and at the first favorable opportunity they 
 put forth their energies, only to have a useless growth, 
 nipped by an untimely frost, or smothered out by their 
 hardier companions. One finds it difficult to make this 
 lavish extravagance, and apparent waste of vital force, 
 conform to human ideas of economy. 
 
 Make the function the central thought in the study of 
 fruits, and introduce the study of the parts with their 
 names as needed to explain it. With the child, the func- 
 tion of fruit has been fulfilled when it becomes an article 
 of food for himself. There are, indeed, older people who 
 see no further. Yet with the proper suggestive instruc- 
 tion, the colors, the edibility, the hooks and prickles, and 
 the various sails and wings with which fruits are provided 
 will reveal such a refinement of means to an end that it 
 seems almost impossible, at first, to account for them ex- 
 cept on the supposition of intelligence in the plant. Still 
 further;Btudy gives the pupil a glimpse of the final conflict 
 of the year in the great~ struggle among the plants for 
 supremacy. Observation will show the effect of the 
 strong early growth upon the maturing seeds; they are 
 
38 NATURE STUDY. [September 
 
 usually better tiquipped in every way than the unfortu- 
 nates of later growth. From such studies the pupil's 
 notions of how the world's life has come to be what it is, 
 and of the enormous length of time involved, will be 
 broadened and strengthened. 
 
 1. Can you find any seeds germinating at this time? 
 Are they of this year or last year's growth ? Can you 
 find any seeds in the ground that have lain there during 
 the summer without germina'ting ? If so, can you account 
 for it ? 
 
 2. Have plants finished their growth for this season ? 
 How can you tell ? Make measurements for at least two 
 weeks before deciding as to the growth of the plants. 
 
 3. 'Vyhat do these growths consist in ? What ones are 
 permanent, what probably for the season only ? 
 
 4. Compare by measurement the'lengths added to the 
 twigs of different trees. Have the old ones added as 
 much as the; young ones ? 
 
 5. On what part of the tree have the longest twigs 
 grown ? 
 
 6. Can you notice any difference in this respect be- 
 tween the north and south sides of a tree ? 
 
 Do not trust to single observations for the answer to 
 these questions. Take the mean or average of at least 
 ten. 
 
 7. Are the new twigs undergoing any change at this 
 time ? 
 
 8. Examine closely the leaves ; on a branch bearing 
 fifty. How many do you find free from insect depredations? 
 In how many ways have they been used by animals ? 
 
 9. Do any plants appear to be the especial prey of in- 
 sects ? 
 
 10. What ones seem to be freest from them ? Can you 
 
September] BOTANY. 39 
 
 see any reason for it ? Give at least two weeks for ob- 
 servations. 
 
 11. In what way, if any, can you see the effects of the 
 weather of this month upon vegetation ? Is it promoting 
 growth or retarding it ? Is it tending to mature the young 
 parts or to prevent their maturing ? 
 
 1 2. What fruits are ripening this month ? Write a list 
 of all you have seen. _ • 
 
 Make a number of envelopes about 3x4 inches out of 
 manilla paper, and collect and preserve in them seeds of 
 all the different kinds of plants as they ripen. These will 
 be used in the spring when studying germination. A 
 great variety is then desirabi.e, and cannot at that time be 
 ' easily obtained. 
 
 13. How do you account for the brilliant colors of some 
 fruits, as in the case of the berries ? 
 
 14. What color is most common amongst ripened fruits ? 
 Why is it so ? What color is next ? 
 
 15. Are there any plants whose fruits do not change 
 color in ripening ? What other changes take place while 
 ripening? 
 
 16. What color prevails in unripe fruit ? Can you see 
 a reason for it ? 
 
 /17. What parts of the flower become the fruit ? Com- 
 pare as many different kinds as can be found. 
 
 18. Do they allhave any one thing in common ? 
 
 In a strict botanical sense a fruit is a " ripened ovary 
 and its contents." In addition to this there are fre- 
 quently present other parts of the flower, which are so 
 modified as to assist directly or indirectly in the distribu- 
 tion of the seed. Sometimes these accessory parts are the 
 most prominent features and are commonly regarded as 
 the fruit itself. The typical ovary wall, as a whole known 
 
4° NATURE STUDY. [September 
 
 as the pericarp, is made up of three layers ; an outer, 
 called the exocarp or epicarp, an inner, called the endo- 
 carp, and one between called the mesocarp. When the 
 latter is .fleshy, it is called the sarcocarp. The seed has, 
 besides, its own coverings or coats, which closely invest 
 the embryo. The chamber containing the seed is the 
 cell ; often there are several of these in one ovary, in 
 which case the partitioifs are called dissepiments. -The 
 part of the ovary to which the seeds are attached is called 
 the placenta. This is axial if passing through the ovary 
 as an axis, central if standing slalk-like in the middle of 
 the ovary, basal when the seeds are, clustered about a 
 point in the bottom of the j3vary, and parietal when the 
 seeds are attached to the ovary wall. The classification 
 of fruits is based upon the different development of these 
 parts. 
 
 19. Select a number of fleshy fruits for study, such as 
 the grape, tomato, cucumber, melon, squash, and apple. 
 In what respects are these all alike ? By drawings or 
 paintings, represent the different parts of these fruits, to- 
 gether with the leaf and twig of the plant. 
 
 20. Can you see any reason for the different colors ? 
 
 21. Why is purple a good color for grapes when ripe? 
 How would red or yellow do ? 
 
 Keep in mind the wild state of the fruits in trying to 
 account, for their characteristics. 
 
 22. On what part of the plant are the fruits most 
 highly colored ? Are they equally colored on all 
 sides ? 
 
 23. Of what advantage is it to certain fruits to acquire 
 a hard or tough rind when ripening ? 
 
 24. What parts of these fruits have been most devel- 
 oped by cultivation ? 
 
September] BOTANY. 41 
 
 25. Select and in the same way study the stone fruits, 
 such as the peach, plum, and apricot. 
 
 26. What parts o£ the flower form the fruit in each 
 case ? Mate drawings and paintings of the structure. 
 
 27. How has cultivation affected the plants bearing 
 these fruits ? Does it tend to make them more or less 
 hardy ? 
 
 28. Where do these fruits grow in their wild state ? 
 
 29. Are the locations where they flourish under culti- 
 vation similar to those where they grow wild ? 
 
 30. Which of the fruits studied are most preyed upon 
 by insects ? Which the least ? 
 
 31. What animals eat the ripened fruit in its wild 
 state ? 
 
 Books for Reference. Humboldt Library : Nos. 115 and 116, 
 Darwinism, by Alfred Russel Wallace ; chapters on Variation and 
 Colors of Plants. No. 26, The Evolutionist at Large, chapters ii 
 and ix. No. 64, The Distribution of Life. Origin of Cultivated 
 Plants (International Scientific Series). Field and Forest Botany ; 
 Gray. 
 
In the study of Physics the most important conception 
 for the child to gain is that concerning the nature of the 
 forces, exclusive of those termed chemical, which act 
 about him and upon him, in a great measure condition- 
 ing his existence. Experiments illustrating the action of 
 these forces, as exhibited in the many varied natural 
 phenomena of rain, snow, frost, dew, clouds, heat, light, 
 magnetism, etc., together with the general principles 
 underlying mechanics, may be performed by the children, 
 under careful supervision, with comparative ease. The 
 idea which prevails to some extent, that work of this kind 
 does not possess the interest for young pupils that the 
 study of animals and plants does, is a mistaken one. If 
 the experiments are properly selected they will not fail 
 to absorb the attention, for the reason that the children 
 will be able to see the cause of certain vital phenomena that 
 otherwise could not be understood. , An error often niade 
 is the failure to impress the fact that an experiment is 
 not an end in itself, but is valuable only as it throws light 
 upon some phase of nature. Expensive apparatus is un- 
 necessary ; for elementary work it is more often a hin- 
 drance than a help, in that it tends to distract attention. 
 A little ingenuity on the part of teacher and pupil will 
 readily supply nearly all that is needed. 
 
 LIGHT. 
 I. Place in a window where the direct sunlight will 
 strike it a small glass prism. Near it on the side next 
 
September] PffYSICS. 43 
 
 the sun place a piece of cardboard in which there is cut 
 a small slit. Let the sunlight pass through the opening 
 and strike the prism. 
 
 A prism may be made by taking three strips of clean 
 glass of equal length and, width, and placing them to- 
 gether so as to form a triangular prism. Cut a trian- 
 gular piece of tin half an inch larger than the end of 
 the prism and bend up outside so as to form a bottom. 
 Seal all the seams with common sealing wax, an-d fill with 
 clear water. Place on a support in the window and turn 
 it until the spectrum falls upon the opposite wall or some 
 other suitable screen. 
 
 2. What changes does the prism make in the sun- 
 light? 
 
 3. Are the colored rays in a straight line with the sun- 
 light that enters the prism ? 
 
 4. Which rays are nearest to a straight line with it ? 
 Which are farthest from it ? 
 
 5. How many colors can be distinguished ? 
 
 6. Place a piece of white paper in the different rays ; 
 what color does it appear to be ? 
 
 7. Make use of these colors in describing the tints of 
 fruits, insects, and autumn leaves. 
 
 MAGNETISM. 
 
 Magnetize a large knitting needle by rubbing it over 
 the poles of a magnet, and thrust it through a cube of 
 wood or small cork half an inch in diameter, so that the 
 needle will balance upon it. Attach a strong silk thread 
 to this and suspend it from the ceiling or other support, 
 where it will not be disturbed by air currents. Each 
 pupil may make his own magnetic needle, using a sewing 
 needle for the purpose. 
 
44 NATURE STUDY. [Septembef 
 
 1. When suspended, what direction does the needle 
 assume ? 
 
 2. Will it remain in any other position ? 
 
 , 3. Find, before magnetizing, the exact point at which 
 the needle balances ; when magnetized and suspended 
 from the point, is the needle horizontal ? 
 
 The variation from the horizontal is known as the dip 
 of the needle. This increases gradually northward to a 
 point near Boothia Gulf, when it stands vertical. This is 
 called the North Magnetic Pole. 
 
 4. Is each end of the needle attracted by both poles of 
 the magnet ? The north end of the needle is called its 
 positive pole, the south end the negative pole. 
 
 5. Which pole of the needle does the north pole of the 
 magnet (usually marked N) attract ? Which does the 
 south pole attract ? 
 
 * A compass consists of a needle magnetized and deli- 
 cately poised on a pivot, so as to turn freely, and pro- 
 tected by a case provided with a glass top. Small 
 magnets may now be purchased for one cent each. 
 
 6. How many useful purposes can you think of to 
 which the compass may be devoted ? 
 
 7. When would the needle in the room be the most use 
 to you ? What two directions does it give directly ? 
 What two, indirectly ? 
 
 8. Make use of this needle in determining the direction 
 of the wind ; of the road home ; the direction toward 
 different places, buildings, etc., in the neighborhood, etc. 
 
 Use the magnets in testing for iron and steel amongst 
 metals. 
 
 In most places the needle does not point toward the 
 true north ; east, of a line running through Wilmington, 
 
September] PHYSICS. 45 
 
 N. C, Charlottesville, Va., and Pittsburgh, Pa., the dec- 
 lination from the true north is toward the west ; west of 
 it the declination is toward the east. 
 
 _B00KS FOR References. Humboldt Library : No i, The Earth 
 a Magnet. No. i8, Appendix. An elementary lecture on Magnet- 
 
'Cbemietr^. 
 
 FERMENTATION. 
 
 By means of a large-sized grater reduce a considerable 
 quantity of the different fruits to a pulp. Press the juice 
 through muslin or cheese cloth and bottle it. When 
 the pupils have tested the juice so obtained by taste 
 and have learned how it is obtained, a quart of sweet 
 cider divided up into four or five bottles, and allowed 
 to stand, will illustrate the changes which take place 
 during fermentation. The different conditions under 
 which they are placed will reveal those most favorable to 
 the change. 
 
 The formation of hard cider is due to what is called 
 alcoholic fermentation. The source of this is the yeast 
 plant, which in its growth breaks up the sugar which the 
 juice contains into alcohol, carbonic-acid gas, and small 
 amounts of other substances. After the alcoholic fer- 
 mentation, the souring or change to vinegar is due to the 
 formation of acetic acid in acetic fermentation. These 
 changes may be followed and noted as they occur. The 
 teacher should be particular to have the children do this 
 work in a neat and cleanly manner ; otherwise they should 
 not do it at all. 
 
 1. Note carefully the taste and color when freshly pre- 
 pared. 
 
 2. Place different bottles under different conditions : 
 
 4« 
 
September] CHEMISTR Y. 47 
 
 some corked, others open ; some in a cool, others in a 
 warm place, etc. 
 
 3. Under what conditions do the changes occur most 
 rapidly ? 
 
 4. Add a little yeast to some of the juice, and vvhen 
 fermentation has taken place it will be ready for distilla- 
 tion. (See Physics for October.) 
 
 5. Do the bubbles which rise contain air ? 
 
 6. Test by lowering into a half-filled jar a lighted 
 match or taper. Does it behave as it does when lowered 
 into air ? 
 
 7. By means of a bent glass tube through the cork of 
 a bottle, force some of the gas into some lime water. 
 Note the change. The tests with the 'flame and lime 
 water indicate carbonic acid gas. 
 
 8. Can you account for the cork being blown from a 
 tightly corked bottle while fermentation is taking place ? 
 
 9. Is the liquid remaining in the bottle after fermenta- 
 tion the same substance that was there before it took 
 place ? How can you tell ? 
 
 10. The change which has taken place is called a 
 chemical change. 
 
riDetcorolog^. 
 
 GENERAL DIRECTIONS AND SUGGESTIONS. 
 
 In order to carry out successfully the work under this 
 head, it is necessary that the pupils make daily observa- 
 tions for themselves, and that these be recorded neatly in. 
 some systematic manner, so that summaries can be readily 
 made from which correct inferences may be drawn. For 
 this purpose a blank form has been prepared, a model of 
 which is, given on another page. This may be prepared 
 by each pupil himself, and should be on a sheet about 
 S}i by 1 1 inches. One such sheet will contain, without 
 crowding, a month's observations and summaries.* An 
 enlarged form of the blank, sufficient for a week's record, 
 should be drawn upon the blackboard, and the daily ob- 
 servations written thereon by the pupils. To save time 
 and avoid the confusion naturally arising from the vary- 
 ing accuracy in different observers, it is better to assign 
 the work to a different pupil each day. This places him 
 subject to the criticism of the entire class, and will pro- 
 mote carefulness in observation. His record, however, 
 should not be changed simply because it does not agree 
 with that of some one else, or with even a majority. 
 Each pupil's work must stand for itself. 
 
 * Printed blank forms of this Meteorological record have been pre- 
 pared by the author, and have been embodied in a notebook for gen- 
 eral science work, 
 
 48 
 
September] METEOROLOGY. 49 
 
 Select a time when it will be most convenient each day 
 to make the record, and adhere strictly to it. It may, 
 of course, vary within certain limits ; as, for example, be- 
 tween 2 and 3 p. ivr. To get data of greater general value, 
 divide the school into three divisions and assign to the 
 first, the time, say, between 9 and 10 a. m.; to the second, 
 an hour near the middle of the day, and to the third the 
 last hour. The average for each day can then be found 
 when making up the summary for the week. 
 
 Teachers sometimes make the serious mistake of de- 
 manding strict uniformity in the records made by the 
 pupils. Such uniformity could hardly be expected from 
 a trained body of scientific observers, mach less must it 
 be looked for among children who are beginning. It is 
 absolutely fatal to the good which may come of the work 
 to the individual pupil, if the teacher falls into the very 
 common habit of deferring to two or three of the brightest 
 ones respecting certain observations, and then requiring 
 the rest to abide by their decision. Better far let each 
 pupil record his own observation, without discussion or 
 reference to what his neighbor is doing, though you may 
 know at the time it is entirely wrong. It is not a mistake 
 which will immediately endanger his life, and he will have 
 abundant opportunity to correct himself in future observa- 
 tions and in the discussions which follow, and thus his 
 own blunders will tend to make him rnore acute in observ- 
 ing. In most cases the pupil's work will have enough of 
 accuracy about it to give him self-reliance, and his mis- 
 takes will continually admonish him to be cautious. 
 
 If for any reason a day is missed during the week, let 
 the space remain blank. Do the work at the proper time 
 or not at all. No one should be permitted to copy any part 
 of the work from another under any circumstances. 
 
5° NATURE ST^UDY. [September 
 
 In the column under " Frost or Dew " write " Frost," 
 " Dew," or " Neither,'' as the case may be. 
 
 If the wind is changing it may be denoted, for example, 
 thus : S— W, indicating a south wind is becoming a west 
 wind. Pupils may learn its direction by watching the 
 drifting smoke from chimneys. 
 
 The kinds of clouds should be named, and, with the 
 sufiRciently advanced pupils, the amount of cloudiness ex- 
 pressed in tenths, indicating the area above the horizon 
 that is covered. 
 
 The thermometer should hang on the north side of the 
 building, free from it, but somewhat protected. Hang 
 the barometer where freely accessible, and so that the 
 upper end of the column of mercury will be on a level 
 with the pupil's eye ; but it must not be too much exposed. 
 
 Rainfall may be expressed as light, heavy, or none, and 
 the number of hours and time when it fell may be re- 
 corded. Example, Light, i:oo — 4:30 p. m. 
 
 The records for the remaining columns may be taken 
 from an almanac, inasmuch as the pupils will hardly be 
 able to gather the data themselves with an accuracy 
 sufficient for the purpose required. Much of the material 
 here tabulated will be used under the lessons in Astron- 
 omy, and it is of great advantage to have it so that a 
 month's record' may be scanned at a glance. The pupils 
 will soon begin to find out in these columns a series of 
 causes whose effects appear in the others. 
 
 Represent the moon's phases by small drawings of the 
 new moon, first quarter, half full moon, and last quarter, 
 making the horns of the waxing moon to the left and of 
 the waning moon to the right. The new moon may be 
 represented by an open circle, and full moon by one that 
 is shaded. 
 
September] METEOROLOGY.' $1 
 
 Both weekly and monthly summaries should be made 
 out at the proper time. The character and fullness of 
 these will depend upon the age of the pupils, but may in- 
 clude the following points : (i) Number of dews or frosts, 
 indicated thus : 3 D. 2 F. 2 N.; (2) prevailing wind ; (3) 
 number of cloudy days, and number of clear days'; (4) 
 number of days on which raia fell ; (5) mean tempera- 
 ture ; (6) mean baroineter ; (7) length of day ; (8) 
 total increase or decrease in day's length ; (9) total 
 variation in time of rising or setting of moon. 
 
 In the consideration of the questions and suggestions 
 which follow there should be a constant search for the 
 causes underlying the phenomena observed. It is not ex- 
 pected that each set of questions will be " finished " be- 
 fore taking the next. Many of the questions are of such 
 character as to require the data which may be collected 
 during seve.ral months' observation before they can be sat- 
 isfactorily answered. The teacher must carefully note the 
 ability of the pupils to think, and thus determine to what 
 extent the questions should be pursued, being careful to 
 go no farther than the pupils' knowledge of geography 
 and physics will warrant. The aim is twofold — to make 
 him intelligent respecting the forces about him, and to 
 train him in the habit of studying a subject for himself in 
 its relations to other subjects. The teacher is too apt to 
 try to push the pupil faster than he should go by simply 
 -telling him facts, instead of patiently giving him intelli- 
 gent assistance in gathering them for himself. 
 
 If it is desired to measure the amount of rainfall, a rain 
 gauge can be made by a tinsmith at small cost. For de- 
 scription and drawing of one, as well as for valuable hints 
 regarding meteorological observations, see " Instructions 
 to Voluntary Observers of the Signal Service," a pamphlet 
 
52 NATURE STUDY. [September 
 
 which may be obtained free by sending to the Chief Sig- 
 nal Officer, Washington, D. C. Daily Signal Service 
 maps may be obtained, also, by applying to the officer in 
 charge of the nearest signal station. They will be found 
 to be interesting and useful in making comparisons, and 
 in enabling one to trace the great storms across the 
 country. 
 
 Most of the following questions may be used in study- 
 ing both the weekly and monthly summaries. 
 
 The accompanying charts show how the pupils may be 
 taught to represent gra.phically many of the summaries 
 which they should be required to make of their meteor- 
 ological and astronomical observations. In each chart, 
 part, or in some cases the entire record for the year from 
 September, i8go, to September, 1 891, is represented for the 
 purpose of illustrating their use. 
 
 In Chart I the record begins September 25, the date 
 when the day and night are equal. At that time the slant 
 of the sun's rays at noon at Chicago as found by the 
 shadow-stick is 43°. At the equator the slant is 0° 
 which is shown to the left of the chart. At about the 
 same time in October the slant is found to be 54°, or 11° 
 more than in September. Since each space between the 
 horizontal lines represents 4°, by measuring down the 
 October line to the point for 54° is readily found. 
 These two points are now connected by a straight 
 line, and the work is thus continued frorrj month to 
 month. 
 
 In Chart II, it will be seen that while in Chart I the 
 line moved downward indicating the increasing slant of 
 the sun's rays, here the line moves upward, showing a cor- 
 responding decrease in the length of day. The down- 
 ward line representing in the left hand side the increasing 
 
September] METEOROLOGY. 53 
 
 length of night in the same time. Chart I indicates a 
 cause and Chart II represents a very closely corresponding 
 effect in the length of day and night. It will be noticed 
 that the figure representing the short days and long nights, 
 (the one on the left) is smaller than the one representing 
 the long days and short nights. Also that the longest day 
 is 15 hrs. 5 min. long while the longest night is but 14 
 hrs. 45 min. long ; that the shortest day is 9 hrs. 15 min. 
 and the shortest night 8 hrs. 55 min. long. Also, that 
 from September 25 to March 17 there are but 173 days ; 
 while from March 17 to September 25 there are 192 
 days. These are only a few of the many problems 
 which a comparison of the charts will suggest. 
 
 In Chart III, the column of figures to the left represents 
 degrees of temperature. By means of these, the point 
 which will represent the mean temperature for each month 
 on the vertical line will be easily found. Why is it that 
 the line on this chart corresponds less closely to that 
 on Chart I ? 
 
 In Chart IV each horizontal space represents one- 
 tenth of an inch, and the column of figures to the left 
 enables the pupils to readily find the points on the verti- 
 cal lines which represent the mean height of the baro- 
 metric column. The reduction to sea level need not be 
 made by the pupils, but tables and formulas showing how 
 it' is done are given in "Instructions to Voluntary Observ- 
 ers of the Signal Service.'' 
 
 Chart V needs no explanation, the name of the month 
 being written at the end of the arrow which indicates the 
 direction of its prevailing wind. 
 
 Chart VI shows at a glance the total rainfall for each 
 month and for the year, each horizontal space represent- 
 ing one-half an inch. 
 
54 NATURE STUDY. [September 
 
 Chart VII shows the number of rainy days in each 
 month and for the year. This chart was prepared from 
 the Signal Service Reports, in which not less than one- 
 hundreth of an inch is considered. The pupils may easily 
 make the record without any measurements, merely keep- 
 ing count of the days on which rain falls. 
 
 As these charts are being made from month to month 
 they should be constantly compared with each other for 
 tlie purpose of tracing points of correspondence and dif- 
 ference. Lead the pupils to find out which of the charts 
 represent causes and which represent effects of those 
 causes, and which ones, if any, appear to be independent 
 of the others. Compare the three representing the mean 
 barometer, rainfa,ll, and direction of wind. Note the ex- 
 tremes shown during each season and for the entire year. 
 The study may be pursued with almost endless variation 
 and will be -found useful in working out the problems 
 and suggestions given in the Outlines under the heads 
 of Meteorology and Astronomy.* 
 
 1. What wind was accompanied by the lowest temper- 
 ature ? The highest temperature ? Can you give a good 
 reason for this ? 
 
 2. Is the temperature increasing or diminishing ? 
 
 3. Did the prevailing wind accompany a cloudy or 
 a clear sky ? 
 
 * These charts are prepared in book form by the author, of suitable 
 size for school use, in the Science^Record for the common schools. 
 This record also contains twelve pages of blank Meteorological Rec- 
 ords, one for each month, twelve pages of blank records for minerals, 
 with a synoptical key to the terms used in description, twelve pages 
 for notes on the regular science work for the year, twelve pages for 
 notes on miscellaneous observations, and twelve pages of drawing 
 paper for drawings and paintings. The size of the page is 8^x11 
 inches. 
 
September] METEOROLOGY. 55 
 
 4. What direction was the wind on cloudy days ? 
 What wind prevailed on clear days ? 
 
 5. Was the prevailing wind accompanied by wet or 
 ■dry weather ? Consult maps and globe in looking for a 
 reason. • 
 
 6. What was the character of the weather when the 
 barometer was lowest ? Note temperature and direction 
 of wind. 
 
 7. What was the weather like when the barometer was 
 highest ? 
 
 8. What were the indications of the thermometer and 
 barometer when the heaviest rain fell ? 
 
 9. What change followed with clearing weather ? 
 
 10. Watch closely the indications of the thermometer 
 and barometer, before, during, and after rainfall ; are 
 they uniform ? 
 
 11. At what time of the day is the temperature high- 
 est ? What reason can you see for this ? 
 
 12. What kind of weather has prevailed on the days 
 on which there was no dew ? Has there been any 
 uniformity in the weather on days when there was 
 dew ? 
 
 13. What was the character of the nights when there 
 was no dew ? When there was dew ? 
 
 14. Is dew to be found everywhere and upon all kinds 
 of objects ? 
 
 STUDY OF SIGNAL SERVICE MAP. 
 
 'Learn well the meaning of the various lines and sym- 
 bols used on the map, and explained in the margin. 
 
 15. Note the general direction of the isotherms. In 
 what region do they vary most from this direction ? 
 
 16. What effect do the mountain ranges have upon the 
 
56 ~ MATURE 5TtJpy. tSeptembSf 
 
 lines ? The Great Lakes ? The coast lines ? The 
 river valleys and basins ? 
 
 17. Note the regions marked "Low" and "High." 
 Which marks a storm center ? Where have most of these 
 entered the United States during September ? 
 
 t8. How does the wind blow about these centers ? 
 Can you discover any uniformity in this regard ? 
 
 19. What has been the direction of storm movement 
 during September ? 
 
 20. Has the movement been visibly influenced by 
 mountains, river valleys, or coast lines ? 
 
 Books for Reference. Light Science for Leisure Hours. Hum 
 boldt Library, No. I, chapter on Tornadoes. 
 
September] 
 
 METEOROLOGY. 
 
 57 
 
 Scpl.OcLN'oT.Dec.JaD.Feb.MchAprJIIayJuno J'fAug.Sept. 
 
 w 
 
 .IB" 
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 12" 
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 63° 
 
 
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 62' 
 
 
 
 
 
 
 
 
 
 
 
 67" 
 
 
 
 
 
 
 
 
 
 Chart I. — Showing variation in the slant of the sun's rays at Chi- 
 cago from September to March inclusive. Record taken from the 
 shadow-stick of the eighth grade. Cook County Normal Practice 
 School. (Not absolutely correct.) 
 
 9 hours 
 
 
 21st 
 
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 U7tl 
 
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 17th 
 
 25th 
 
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 Chart II. — Showing the variation iii the length of day and night 
 during the year at Chicago. 
 
September] 
 
 METEOROLOGY. 
 Octoboi; 
 
 59 
 
 Septemlter 
 
 Novciuber 
 Sccoiuber 
 January 501 
 
 Fefcriiary 
 
 Chart V. — Showing prevailing winds at Chicago for each month 
 from September to May inclusive, 1890-gi. 
 
 ^ . . Se pt. Oct. MoY. Dpc. Jnn. Fob. March Apr. May June July Ang. St-p t. 
 
 .5 
 
 1.0 
 
 1.0 
 
 2.0 y 
 2.S 
 8.0 '■ 
 8.S 
 4.0 
 4.5 " 
 
 5.0 y 
 
 Chart VI. —Showing rainfalLat Chicago for each month from Sep- 
 tember to May inclusive, iSgOrgi. 
 
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astronomy. 
 
 GENERAL DIRECTIONS. 
 
 In following up these observations with explanations, 
 it is necessary to be provided with a globe, or a good 
 substitute, and objects to represent the sun, moon, and 
 planets. 
 
 If an open space on the floor, a few feet square, is avail- 
 able, a spot in the middle should be selected to represent 
 the position of the sun, and ellipses drawn around it with 
 light lines of paint to represent the orbits of the planets. 
 
 The surface of a large table may be used if floor room 
 cannot be obtained. Representing the distance of the 
 earth frorn the sun by i,.the distance of the planets may 
 be approximately represented as follows : Mercury ^ ; 
 Venus f ; Earth i ; Mars ^ ; Jupiter 5 ; Saturn 9 ; Uranus 
 20 ; Neptune 30. For the purposes of illustration in the 
 following lessons it will be more convenient to represent 
 the earth's distaiice on a ^larger scale than that on which 
 it would be practicable to represent the whole solar sys- 
 tem. The varying length of shadow should be observed 
 throughout the year. To do this, take a strip of wood 
 two feet long and two inches in width, and to one end 
 nail an upright strip of same width and four inches 
 high. At noon place the long strip in a horizontal posi- 
 tion on a north and south line with the upright toward 
 the south. With a pencil and ruler draw a line across 
 the horizontal strip marking the limit of the shadow cast 
 
 61 
 
62 NATUKE STUDY. [September 
 
 by the upright. Note the date each time. The angle 
 made by the sun's rays may be found thus : Take a stiff 
 piece of cardboard six inches square, describe upon it a 
 circle, and if a protractor be at hand, lay off one-half 
 the circumference in degrees. Tack or paste this to a 
 piece of wood of same size as the cardboard and one- 
 half inch thick ; along the edge of this, opposite the 
 semicircle that is marked off in degrees, tack a straight 
 strip of wood half an inch square and one foot long. 
 Cut from a piece of tin or thin brass a pointer six inches 
 long, and swing it on an axis or pivot fastened at the 
 center of the circle. Make the end opposite the pointed 
 ,one heavier, so that it will always hang down when the 
 dial is upright. This may be accomplished by cutting 
 that end considerably longer than necessary and then 
 rolling it up till it falls within the circle on the dial. To 
 number the degrees on the dial, place it upright so that 
 the stick which is fastened to the base will be horizontal. 
 The pointer will then be vertical, and zero degrees may 
 be marked at this point. As either end of the stick is 
 raised the pointer will still remain vertical, and indicate 
 the number of degrees it is raised from the -horizontal. 
 To get the angle of the sun's rays, place one end of the 
 stick at the extreme edge of the shadow and allow the 
 other to rest on the top of the upright which casts it. 
 The pointer will give the number of degrees the sun is 
 above the horizon. 
 
 The most important conception for the children to get 
 in this study is that of time, and a conception of space is 
 next. When necessary, daily practice should be given 
 the children in telling the exact time of day by clock or 
 watch, until they can do so without hesitation. Of course, 
 merely telling the time of day will not in itself give a con- 
 
September] ASTRONOMY. 63 
 
 ception of time, and such exercises as will enable them to 
 grasp brief periods must be given in connection with it. 
 As for example, let them find out how long it takes them 
 to walk home ; or, the length of the recitation period, or 
 of the morning and afternoon sessions of school, the 
 recess and noon periods, etc., and they will soon fix in 
 their minds a stock of time units which will be of great 
 service. 
 
 1. What do you notice about the relative length of day 
 and night at the beginning of the month ? 
 
 2. With a globe and some object to represent- the sun, 
 find out the relative positions of the two bodies when day 
 and night are thus related in length. 
 
 3. How does the length of each vary during the month ? 
 
 4. Using the globe as before, explain this change. 
 
 5. How has the length of the noon shadow changed ? 
 By using the globe explain this. 
 
 6. Observe as accurately as possible the two points on 
 the horizon where the sun rises and set's on that date in this 
 month when day and night are equal. Fix these points 
 with respect to yourself by means of a tree, post, or some 
 permanent mark, and keep in mind for reference in future 
 observations. A line connecting these two points runs 
 east and west. Compare the length of day and night. 
 This date is the time of the Autumnal Equinox. 
 
 7. Make a brief note of the condition of animal and 
 plant life at this time and preserve for future reference. 
 
 Among the interesting constellations that may be ob- 
 served during this month are : Great Bear, Little Bear, 
 Draco,. Cassiopeia, Cepheus, Pegasus, Sagittarius, Lyra, 
 Cygnus, Dolphin, Hercules, Corona, Berenice's Hair. 
 
 Books for Reference. Science Primer, Astronomy, Lockyer. 
 The Wonders of the Heavens, Humboldt Library, No. 14. 
 
(Beoarapb^. 
 
 Geography is defined as a description of the earth. 
 This embraces everything that may be said of the earth, 
 but it is usually understood to have a more limited mean- 
 ing. It is sometimes said to be a study of the earth as a 
 finished product ; that cannot be strictly true, for it is no 
 more a finished product to-day, in the sense that it is in a 
 fixed condition, than it ever was. It has been constantly 
 changing from the remotest periods of time under the 
 operation of certain laws, and those laws are still affect- 
 ing it. The changes in the earth itself, and in its relations 
 to the other portions of the universe, have produced cor- 
 responding modifications in living things ever since mun- 
 dane life began to exist. They are so gradual as to have 
 had but the most trifling import in the time spanned by 
 human history, yet it is believed that by them the earth 
 has been brought out of a nebulous condition to its present 
 state. Life, both animal and plant, by its amazing plas- 
 ticity adapting itself to almost every corner of the globe, 
 has managed to survive and perpetuate itself throughout 
 countless ages of a vast period, in whiqh the changes have 
 been almost incredible. 
 
 Geography, as it is to be understood here, is the study 
 of the earth in its present condition as a cause, of which 
 life upon it is the effect. It comprehends a study of the 
 earth in its present relation to life, and a study of life, as 
 it now exists in its adaptation to the earth. 
 
 64 
 
September] GEOGRAPHY. 65 
 
 DIRECTION. 
 
 Teach the cardinal points and apply in giving the 
 direction of the wind, movement of clouds, etc. (see 
 Meteorology), and in the location of articles in the room, 
 school-yard, and vicinity. 
 
 Countless problems may be proposed by both teacher 
 and pupils which will give zest to the work and cultivate 
 a habit in the children of keeping their bearings when 
 moving about from place to place. The unpleasant ex- 
 perience which most people have had of being " turned 
 round," when in a strange place, as to the points of the 
 compass, is probably due chiefly to the fact that they do 
 not habitually observe fixed landmarks with respect to 
 the cardinal points on the horizon while traveling. The 
 pupils should be practiced in this until it becomes a fixed 
 hahit, and they are able to hold the different directions 
 in mind without conscious effort. 
 
 With this work, map making properly begins. If one 
 pupil says that in going home he travels three blocks east 
 and two north, let him show how the path looks on the 
 blackboard. Let him locate his home and the school- 
 house with respect to each other. This will necessitate 
 the teaching of direction as applied to maps. 
 
 LATITUDE AND LONGITUDE. 
 
 In beginning with pupils to use latitude and longitude 
 in the location of places, if it can be avoided, never use a 
 flat map. A globe is the only thing that can give a cor- 
 rect idea of the parallels and meridians as they are re- 
 lated to each other. 
 
 I. Locate the equator and the poles on the globe. 
 What is the position of the equator between the poles ? 
 
66 NATURE STUDY. [September 
 
 2. Huw far from the equator to the poles ? Teach the 
 number of degrees in a circle, half circle, and quadrant. 
 
 3. When the rays of the sun just reach either pole, 
 where are the vertical rays ? On what date is this the case ? 
 
 4. What do you notice about the length of day and 
 night at this time ? 
 
 5. When the sun is vertical at the equator, what is the 
 angle of the rays in our latitude at noon ? (See Astron-- 
 omy for September.) 
 
 6. What determines the size. of the angle at this time ? 
 
 7. How would the angle change if we moved north ? 
 If we moved south ? If we moved east or west ? 
 
 8. If you know the angle of the sun's rays at noon at 
 a given place when the sun is vertical at the equator, how 
 can you find the latitude of that place ? 
 
 9. In what latitude have the severest storms originated 
 in the United States this month ? (See Signal Service 
 Map Studies for September.) 
 
 iQ. How many degrees of longitude has the heaviest 
 storm passed over ? 
 
 rr. In what latitude have the heaviest rains fallen ? 
 
 12. What latitude has been least visited by storms ? 
 ' 13. In what latitude do the isotherms vary most widely- 
 from their general course ? In what latitude do they vary 
 least ? 
 
 14. Since the earth rotates once in twenty-four hours, 
 through how many degrees d^oes each point on the earth's 
 surface pass in that time ? 
 
 15. Upon what circles are the degrees measured ? Are 
 the degrees of the same size qn different circles ? 
 
 16. Through how niany degrees will any given point 
 pass in one hour of time ? .On what circle would a point 
 pass through the greatest number of miles .? 
 
September] GEOGRAPHY. 67 
 
 Longitude is reckoned east and west from an estab- 
 lished meridian, usually that passing through Greenwich, 
 near London, or the meridian passing through Washing- 
 ton. 
 
 17. How many degrees of east or west longitude can 
 
 be reckoned ? Where will there be no longitude ? Where 
 
 no latitude ? 
 
 NORTH AMERICA. 
 
 1. Between what parallels does North America lie? 
 Between what meridians ? 
 
 2. What contrasts between the northern and southern 
 parts, due to difference in latitude, are found in animal 
 life, vegetation, habits, character, and occupations of the 
 people ? 
 
 3. What are some of the advantages of a country that 
 extends through many degrees'of latitude ? 
 
 4. What are the greatest disadvantages due to the same 
 conditions ? 
 
 5. How did difference of latitude, as a cause, enter 
 into the questions involved, in the great civil war in the 
 United States ? 
 
 6. When it is sunrise at New York City, how long be- 
 fore sunrise at San. Francisco ? 
 
 7. When it is sunset at St. Louis, how long after sunset 
 at Washington ? 
 
 To make the pupils familiar with maps and their use, 
 they should begin by modeling and drawing maps of the 
 school-room, school grounds, and surroundings. Mark 
 the natural features of surface, and locate the buildings, 
 etc., that are to be found upon it. Locate on map and 
 globe all places mentioned in his,tory and other subjects 
 studied. This. should be as much a matter of habit as it 
 is to look for the meaning of a word in a dictionary. 
 
(Beolog^. 
 
 The conception of space is of first importance in this 
 study, and that of time is second. Means should be pro- 
 vided in the beginning to enable the pupil to train himself 
 accurately in judging distances, horizontal and vertical, 
 and areas. The deficiency of pupils, even of high school 
 age, in this respect is generally very great. This is almost 
 wholly due to lack of actual practice ; they have talked a 
 great deal about rods and acres, buf have never measured 
 them. 
 
 The units must be adapted to the age and comprehen- 
 sion of the children, but, as needed, one-fourth, one-half, 
 and, if possible, one mile should be laid off, so that the 
 limits may be plainly seen and the distances well fixed in 
 mind. There should be similar opportunities given to 
 study one foot, one yard, one rod, and one hundred yards. 
 For the study of heights, units of ten, twenty-five, and, if 
 possible, fifty and one hundred feet should be marked off 
 on the side of the school-house or some tree. The square 
 foot, square yard, square rod, acre, and later the square 
 mile, will be needed in the estimation of areas. 
 
 It is well to give much attention from the start to the 
 collection of specimens. Every region will furnish an 
 abundance of many different kinds, and they possess an 
 immense advantage over collections in some other 
 branches- of natural history, from the fact that they re- 
 quire little care, except an occasional dusting, and are 
 practically imperishable. Fragments of different rocks, 
 
September] .GEOLOCY. ' 6g 
 
 various kinds and forms of pebbles, and fossils of all 
 kinds, should, when possible, be gathered and neatly ar- 
 ranged. There can hardly be a stronger stimulus for the 
 imagination than that which one receives from the proper, 
 study of a fossil, and there is certainly ilothing which 
 will so broaden one's conceptions regarding the vast ages 
 that make up the earth's history. Arrange in a tray or 
 box certain typical specimens of those belonging to the 
 immediate neighborhood, with which the pupils may com- 
 pare their specimens as they find them. Among these 
 maybe granite, marble, limestone, sandstone, slate, coal, 
 etc. The name should not be given to them by the 
 teacher until they have compared their specimen with the 
 types and learned some of its characters. None the less, 
 however, should the pupils be led to study the dynamical 
 side of the subject. There are everywhere plenty of ex- 
 cellent examples of either building or wearing away, — per- 
 haps both, — which possess an abiding interest. Whatever 
 it may be, whether a crumbling cliff, a building beach, a 
 deepening gulch, or a slowly filling marsh, it makesbut 
 little difference. There to-day the Titans maybe seen 
 making and unmaking the world, as they have been doing 
 it for unnumbered ages in the past. 
 
 1. In looking over the country about you, can you tell 
 what has been the most important agent in its formation ? 
 
 2. Is the same force still at work ? Is it working 
 rapidly or slowly ? 
 
 3. What other'forces have left their impress upon the 
 country ? Are they still acting ? 
 
 4. Are there any evidences as to whether, these forces 
 ever worked more rapidly or more powerfully than 
 now ? 
 
 5. Can you find any place where the land is being torn 
 
7° NATURE STUDY. [September- 
 
 down ? What is doing it ? What becomes of the ma-' 
 terial when torn away ? 
 
 6. Are there any forces which oppose the tearing 
 away ? 
 
 7. Are there any marshes, large or small, in the vicin- 
 ity ? How much of their history can you read in them ? 
 
 8. What was their relation originally to the nearest lake 
 or stream ? 
 
 9. Are they now filling up with earth, or being-hallowed 
 out ? ' 
 
 10. What is vegetation doing for the marsh ? The 
 water ? 
 
 1 1. How does a sod affect the wearing forces oi atiy 
 region ? What are the effects of forests ? 
 
 12. Is the cultivation of the soil in anyway changing 
 the formation of the country ? 
 
 13. What kind of rock underlies the surface ? Do you 
 find more than one kind ? 
 
 14. Are they in layers, i. e., stratified, or in masses that 
 show no stratification ? 
 
 15. If stratified, are the strata horizontal or inclined? 
 When inclined the rock is said to dip. The line along 
 which the edge of the rock cuts the surface is called the 
 strike. It always runs atright angles with the dip. 
 
 16. What is the angle of dip measured from the hori- 
 zontal ? 
 
 17. Does the dip have the same angle in all places? 
 Does it have the same direction ? 
 
 Books for Reference. Humboldt Library, No. 6, Town Geol- 
 ogy. Shaler's First Book in Geology. 
 
fIDineralogi?. 
 
 Give special attention to the collection and arrange- 
 ment of different metals and minerals. Provide a small 
 tray with compartments, in which there should be placed 
 typical specimens of such, at least, as are likely to be 
 found in the vicinity. Place with each one a label bear- 
 ing its degree of hardness, its luster, color, diaphaneity, 
 streak, taste or odor, and name. The scale of hardness 
 consists of ten minerals, showing a regular gradation in 
 hardness from talc, one of the softest, to diamond, one of 
 the hardest minerals. It is as follows : Very soft — i,talc; 
 2, gypsum ; can be scratched with finger-nail, or very 
 easily with a knife. Soft — 3, calcite ; 4, fluorite ; can- 
 not be scratched with the nail, but, easily scratched with 
 a knife. Hard — 5, apatite ; 6, orthoclase ; not easily 
 scratched with 'a knife; scratches glass. Very hard — 
 7, quartz ; cannot be scratched by a knife, scratches 
 glass ; 8, topaz, scratches quartz. Adamantine — 9, cor- 
 undum ; scratched by the diamond and itself. 10, dia- 
 mond } not scratched by any other mineral. 
 
 Luster or glance refers to the light, both as to quality 
 and quantity, which is reflected from the surface. The 
 meta/lic luster is that of the metals. All the other kinds 
 of luster are embraced under the general division non- 
 metallic. The chief varieties are : Vitreous, like glass ; 
 pearly, as in mica or pearl ; resinous, as in resins, sulphur 
 and sphalerite ; silky or satiny, as in satin-spar ; greasy or 
 waxy, as in serpentine. 
 
72 NATURE STUDY. [September 
 
 The degrees of diaphaneity are expressed as trans- 
 parent, translucent, and opaque. The streak is obtained 
 by powdering a little of the mineral by means. of a file, 
 or by drawing it over a piece of ground glass. 
 
 Use the magnet in the examination of metals, and find 
 but which are magnetic and which are not. When a 
 mineral is found by a pupil he should prepare a written 
 description of it, including the characteristics above 
 given, by comparing it with the specimens labeled in the 
 tray. The teacher may then add the name. The col- 
 lecting should be encouraged throughout the year. 
 
 From the beginning the pupils should be taught, in the 
 grammar grades, at least, the best means by which a com- 
 plete but concise record of their observations may be kept. 
 Although it may appear a little tedious at first, its value 
 will be more and more apparent as the record grows. The ; 
 irksomeness of tbe task is usually chiefly due to the fact , 
 that the pupil is urged tp record observations -n^hicli he , 
 • has not really made, and, being no part of his experi- 
 ence, he naturally has no interest iii^them.j He should, 
 record briefly only what he can find out for himself. 
 The blank form for a mineralogical record,' here appended, ■ 
 may be prepared upon the sheet, eight and one-half 
 by eleven inches, which was recommended on a previous 
 page for science work. This will give spiace enough for 
 ten minerals, aiid will be of uniform size with the sheets 
 lipon which his other written work is prepared. 
 
 Books for. Rkference. Crosty's Tables for; the Determination 
 of Common Minerals, Guttenburg's Courseln Mineralogy for Young 
 People (Agassiz Association Course), Crosby's Common Minerals 
 and Rocks, - ' 
 

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Suggestions to Teachers for Using the Mineralogicai 
 Eecord. 
 
 Each pupil should have a blank record. When he finds a mineral, its description is to 
 be written in the blank foruj under the proper heads — the appended outline being 
 used OS a guide. Render the pupil as little assistauce as possible ; he must be self-reli- 
 ant. Do not hurry. When the ^)upil has done his best, the amount vai-yingwith age 
 and practice, the teacher may give him the name of the ihineral. Crosby's Tables for 
 the Detennination of Common Stiuerals is a most valuable manual f oi" teachers. 
 
 I. SCALT5 OF HABDNESS. 
 
 1. Talc, ( VEEif yoFT ; can be scratched with finger nEiil, or vei-y easily with a 
 
 2. G-ypsum, f knife. 
 
 3. Calcite, I 3oFT ; cannot be scratched with finger nail, but easily scratched 
 1. Fluorite, | with a knife. 
 
 6. Orthocfase J ^^^^ ! ^o*- easily scratched with a knife ; scratches glass. 
 
 7. Quartz,) viPTt-v niaT. ■ i Cannot be scratched with a knife ; scratches glasa. 
 
 8. Topaz, f VERTHAUD, j Scratches Quortz. 
 
 9. Corundum,! AT..M««t.™E. .i Scratched by the diamond and itself . 
 10. Diamond, f adamantine, | Not scratched by any other mineral. 
 
 II. Spbcibtc Geavitt. 
 1. Weigh in air. 
 ^. Weigh in water.- 
 S. Specific Gravity=weight in alr+loss of weight in water. 
 
 III. Form. 
 
 Botryoldal— Surface Krape-like. 
 Mammillary— Same, but larger, 
 
 Tufaceous— Porous, mineral Incrustations formed from solu- 
 tions. 
 Concretionary—Rounded masses. 
 Gteode— Hollow concretion. 
 
 Stalactitic— Hanging from under surface of a rock, cone-shaped. 
 Stalagmitic— Formed on floors of caverns from dripping water. 
 Stratified— Deposited inlayers. 
 Granular, coarse or fine— Small crystals. 
 Compact— Crystals invisible to unaided eye. 
 Foliated— In layers. 
 FiBrous— Thread-like, 
 Columnar— Stout, fibrous. 
 Amorphous— Without crystallization. 
 
 IV. TENACaTT. 
 
 1. Brittle— Breaks easily. 
 
 2. Malleable— Flattens mto thin sheets under hammer. 
 
 5. Sectiie— May be cut into thin slices. 
 
 4. Flexible— Retains its form when bent. 
 
 6. Elastic— Comes back to original form when bent. 
 
 V. LUSTBB. 
 
 1. Metallic, as in metals. 
 
 Vitreous, as In glass. 
 
 2. Non-Metallic. 
 
 Pearly, as in pearl and mica. 
 Resinous, as m sulphur, sphalerite, reRins, 
 Pitchy, as in caunel coelI.' 
 Silky or satiny, as in satin spar. 
 G-reasy or waxy, els in serpentine. 
 Imll, as in chalk. 
 
 VIII. Acid Tests. 
 1. Insoluble. 
 
 VI. Streak. 
 
 Color obtained by rubbing the mineral over the surface of a piece of ground 
 glass or over a file. ^ 
 
 VU. Diaphaneity. 
 
 1. Transparent. Semi-transparent. 
 
 2. Translucent. Sub-translucent. 
 
 3. Opaaue. 
 
 Use H CI (hydrochloric acid), or dilute Ha S 04 (sulphuric acid), 
 or both. Use a little of the mineral in a test tube. 
 
 { With effervescence ; with or without heat. 
 2. Soluble. < Without effervescence ; with or without heat. 
 ( Gelatinizes— Becomes Jelly-like. 
 
 IX. Flame Tests. N. B. Use a fine splinter of the mineral, or a thin edge in the 
 flame of an alcohol lamp or bunsen burner. Note the 
 color imparted to the flame. 
 
 1. Fusible— Melta. 
 
 2. Infusible— Does not melt. 
 
 3. Decrepitates— Breaks into small pier- es with crackling sound. 
 
 4. Intumescea— Swells up without fusion. 
 
 74 
 
The larvse of several different species of moths (large 
 green and brown worms) are usually abundant at this 
 time, and should be collected. Put them in small boxes 
 covered with mosquito netting, and feed with fresh leaves 
 of the plant upon which they were found. They will soon 
 spin a cocoon and enter upon a new stage of existence. 
 Carefully preserve these through the winter, and in the 
 spring the moth will appear. There is not a more fruit- 
 ful series of observations possible in the school-room for 
 children than that of watching the wonderful transforma- 
 tion of insects. Ants may be kept under observation 
 during the entire year in glass jars filled with fine damp 
 earth. A better method^ however, is as follows : Get a 
 tinsmith to fasten a small moat, an inch deep and one 
 and a half inches -wide, around a smooth piece of inch 
 board, one foot square, ■ On this board, equidistant from 
 the moat on all sides, lay a pane of glass, ten inches 
 square. On each edge of this, glue a strip of glass, leav- 
 ing small passage ways at opposite corners. Fill the 
 shallow vessel thi]s formed with finely sifted earth, and 
 cover it with another pane of glass of same size as the 
 lower one. Fill the moat with water. Take from an 
 ant-hill a small box of earth and ants a;ll together, and 
 place them in a little heap on the top of the glass. By 
 thrusting a small stick into the den through the passage- 
 ways left at the corners, to give them a place for a beginning, 
 with a little care the ants can be induced to enter and go 
 
16 iVATURE STUDY. [October 
 
 to work. Gradually remove the earth from the top of 
 the glass, wipe clean and keep in the dark by covering 
 the whole with a pasteboard lid, about two inches high. 
 Food — crumbs, sugar, and bits of meat — can be placed 
 under this on the glass. The changes made from day to 
 day in the earth, and the management of the larvae, 
 visible through the glass, are sources of unfailing interest. 
 If a common mud or snapping turtle can be procured, 
 place it in a box of wet sand with a loose lid over it, and 
 in a few weeks it will disappear and remain out of sight 
 till spring, and furnish a text for the interesting subject 
 of hibernation. 
 
 1. What birds have disappeared within the past few 
 weeks ? Note the date when last seen, 
 
 2. Can you tell which leave first, the old ones or young 
 ones ? 
 
 3. Watch for mTgrating flocks of geese from the north. 
 
 4. AVhat becomes of the insects during the cold nights ? 
 Doany of them migrate ? 
 
 5. What becomes of the butterflies? Of the bees? 
 Of the grasshoppers ? Of the flies ? 
 
 6. Can you' find any preparing to live oyer winter ? 
 
 7. Examine the burrows. of earthworms ; are the worms 
 as active as they were last month? 
 
 8. Gather a number of snails from the bottoms of ponds 
 and preserve in glass jars. 
 
 A STUDY OF TISSUES. 
 
 It is of fundamental importance that pupils should have 
 in the outset of the study of physiology correct concep- 
 tions as to the more important tissues of the animal body. 
 The following outline is intended to be used as a guide in 
 making them acquainted with these tissues, and to give 
 
October] ZOOLOGY. 11 
 
 an idea, of their uses. Procure a sheep's leg cut off so as 
 to include what is commonly called the knee joint and 
 the attached muscles a few inches above it. Each pupil 
 should have a specimen which must be perfectly, fresh 
 and clean. The distaste that many pupils acquire for 
 this kind of work, in the majority of cases, arises from 
 carelessness of the teacher on this point. The use of 
 good specimens gives the teacher a perfect right to require 
 each pupil to do the work, and, feeling this, but few will 
 raise any objection. 
 
 THE MUSCLE. 
 
 1. Note the reddish flesh forming the ^o^^ of the muscle. 
 
 2. The slender cord attaching the body to the bone is 
 the tendon of the muscle. Is it elastic or inelastic ? Can 
 it be pulled loose ? Try pulling in different directions. 
 
 3. Note how it is attached to the bone. The point of 
 attachment of the tendon which moves least in any mo- 
 tion of the part is called the origin of the muscle ; the 
 other attachment is its insertion. Locate the origin and 
 insertion of the muscle which flexes the forearm. 
 
 4. Note the thin sheath covering the body ; it is called 
 the perimysium. 
 
 5. Cut the body crosswise and note the parts which 
 compose it. They are best seen in boiled meat. The 
 bundles thus shown are called fasciculi. 
 
 6. Follow out toward the tendons the white threads, 
 and note the formation of the tendon. 
 
 7. Find tendons in your own body ; find the bodies of 
 the muscles to which they are attached. 
 
 8. What advantage in the tendon ? 
 
 9. What is the advantage of its inelasticity? 
 
 10. What uses can you discover for muscle ? 
 
73 NA TURE stud v. [Octobef 
 
 CONNECTIVE TISSUE. 
 
 1. Examine the white, thin tissue surrounding the 
 muscle. 
 
 2. What are its characteristics ? Is it elastic ? This 
 tissue is very abundant in the specimen, as well as in the 
 whole body. It is called connective tissue. It is to be 
 found almost everywhere, binding the different parts to- 
 gether. What characteristics especially adapt it to this 
 end? 
 
 3. In how many forms does it appear in this specimen ? 
 Note the tendons, the perimysium, and the threads which 
 ramify the muscle body. 
 
 THE BONE. OSSEOUS TISSUE. 
 
 1. Note the slender shaft and its enlarged extremities. 
 
 2. What advantage in the enlargement of the ex- 
 tremities ?. 
 
 3. Look for the sheath closely surrounding the shaft. 
 What kind of tissue is it ? The sheath is called the peri- 
 osteum. 
 
 4. Look for the cavity in the shaft called the medullary 
 cavity. Note the contents, called the marrow. 
 
 5. Split the bone ; note the difference in the character 
 of the bone at the extremities and in the shaft. 
 
 6. In the extremities it is called spongy or cancellated ; 
 in the shaft, compact bone. 
 
 7. Note the red marrow in the spongy bone. 
 
 8. What advantage is gained by the tubular form of 
 the bone ? 
 
 9. AVhat advantage in the spongy character of the 
 bones at the ends ? 
 
October] ZOOLOGY. 79 
 
 TO. Can you see any means by which the bone is nour- 
 ished ? 
 
 11. Place a piece of bone in the fire and thoroughly 
 burn it. Put it on live coals, and let it remain over 
 night. 
 
 12. How does the burnt bone diifer from the fresh 
 bone? 
 
 13. After the burning is completed, what must be the 
 nature of the substance remaining ? 
 
 14. Place another small bone in a mixture of one ounce 
 of hydrochloric acid to a pint of water. Note the changes 
 that occur. 
 
 15. How does the part which remains unaffected after 
 a day or two differ from what remains after burning ? 
 This is the animal matter that is in bone. 
 
 16. What properties of bone are derived from the min- 
 eral matter it contains? What from the animal matter? 
 
 17. Animal matter is most abundant in bones in early 
 life, and mineral matter is most abundant in old age. 
 
 18. When are bones iriost likely to be distorted ? When 
 most easily broken ? 
 
 19. Why will bones, distorted for some time, assume 
 permanently this new form ? 
 
 20. What school habits are most likely to distort bones ? 
 
 21. What bones most frequently suffer distortion ? 
 
 22. How many in every ten people that you know are 
 free from these distortions ? 
 
 FAT— ADIPOSE TISSUE. 
 
 i. Look for this about the joint andmuscle. 
 
 2. Squeeze a small piece between the fingers. What is 
 obtained ? 
 
 3. Can you think of any use for it ? 
 
8o NATURE STUDY. [October 
 
 THE JOINT. 
 
 1. What motions are possible at this joint ? Locate 
 those joints in your body which have this motion only. 
 
 2. Such are called hinge joints. Define a hinge joint. 
 
 3. Find the cords which bind the bones together. 
 These are called ligamenls. How do they resemble ten- 
 dons ? How do they differ from them ? 
 
 4. What tissue in the ligaments ? How many can you 
 find at this joint ? 
 
 5. Open the joint with a knife. Note the sticky fluid 
 found inside. It is called Synovia, or the Synovial Fluid. 
 What use can you discover for it ? 
 
 6. With your knife carefully separate the ends of the 
 bones in the joint. 
 
 7. The two surfaces which rub over each other are 
 called the articular surfaces. The soft translucent tissue 
 covering these surfaces is cartilage. When found on the 
 ends of bones in a joint, it is called articular cartilage. 
 The meeting of two bones, as in a joint, is called an 
 articulation. 
 
 8. Why should the ligament be inelastic ? 
 
 9. What causes a sprained joint ? How is the joint 
 injured when sprained? 
 
 10. What must take place in a dislocation? 
 
 11. What occurs in a stiffened joint ? 
 
 12. Review these lessons, and note the use of the word 
 tissue. Can you write a definition of it ? 
 
Botany. 
 
 Watch the plants as a whole as the season changes. 
 Note the disappearance of the sap, the drying of the leaf, 
 the maturing fruit, the hardening of the new wood in the 
 twig, and the newly-formed bud, in which is carefully 
 packed away the destiny of the plant. Animals may 
 hide in tlie earth or flee away to a milder clime, 
 but the plant must face the blasts of winter where it 
 stands, and it prepares itself accordingly. It is a most 
 interesting phase of life. Continue to collect seeds and 
 nuts of all kinds, and carefully dry and preserve them in 
 envelopes. 
 
 1. Examine closely a branch, and find out how and 
 where a leaf breaks away from the twig. Does the 
 petiole or leaf-stalk break ? What kind of a mark or 
 scar remains ? 
 
 2. Are thejre any buds liewly formed ? What, is the 
 relation of these, in position, to the leaf ? 
 
 3. Are there more buds than one to the leaf ? 
 
 4. Can you find, on the older twigs, buds of previous 
 years which did not open ? ' 
 
 5. What influences cause the leaves to change color 
 and drop off? 
 
 6. Does the bark peel readily from the twig ? Is it 
 merely drying fast to the wood ? 
 
 7. How much new wood has been formed this year ? 
 
 8. Where has it grown, in the center or at the circum- 
 ference of the branch ? 
 
82 NATURE STUDY. ^October 
 
 9. Nuts, and the seeds of most weeds, are classed as 
 dried fruits. Why is it they are uniformly of dull colors ? 
 
 10. Can you understand why the edible portion of nuts 
 is protected by a shell, while in berries and such fruits it 
 is not so covered ? 
 
 11. What animals devour nuts? Do they in any way 
 assist in scattering them ? 
 
 12. How else are nuts distributed? Will they float in 
 water ? 
 
 13. How are they protected while unripe and on the 
 tree ? How, when they open and fall ? 
 
 14. Can you make out the various layers of the ovary 
 in the acorn, hickory nut, walnut, and chestnut ? 
 
 15. Is the form of the nut of apy advantage to it ? 
 
 16. Note the various contrivances by which the seeds 
 of weeds, etc., are scattered. How do some manage to 
 use the -wind ? What part of the flower in the dande- 
 lion and thistle becomes the sail ? 
 
 17. What sized plants bear seeds with prickles? Do 
 you see the reason why the size varies within narrow 
 limits ? 
 
 18. What part of the flower becomes the prickle ? 
 
 19. Are the prickles in any case fastened to the seeds 
 themselves ? 
 
 20. If the seeds are caught in the fur or hair of ani- 
 mals, does it not defeat the aim of the plant in producing 
 the prickle ? 
 
 2 1 . Examine a number of these under a lens, and sketch, 
 showing the structure. 
 
 Books for Reference. Humboldt Library : No. 116, chapter 
 xi. No. 33, Vignettes from Nature, chapters xi, xvi, xvii, xxi, and 
 xxii. No. 64, The Distribution of Life. No. 26, chapter xvii. 
 
pb^sics. 
 
 EVAPORATION. 
 
 1. Place small amounts of water in various shaped ves- 
 sels and allow them to stand exposed to the air for sev- 
 eral days. 
 
 2. What becomes of the water ? 
 
 3. Under what circumstances will it evaporate most 
 rapidly ? 
 
 4. Note- varying effects of a wide extent of surface, 
 depth, currents of air passing over the surface, surface 
 protected from currents as in a corked bottle, direct 
 sunlight, darkness, heat, and cold. 
 
 5. What causes mud to dry up ? 
 
 6. What becomes of the dew ? Frost ? 
 
 EBULLITION. 
 
 1. As heat is added to a vessel, what effect is there 
 upon the rate of evaporation ? 
 
 2. Note the changes that occur as the water comes to 
 the boiling point ? 
 
 3. What becomes of the first bubbles? What do they 
 contain .' 
 
 4. What causes the peculiar noise when a vessel of 
 water simmers ? 
 
 5. Note the bubbles when boiling begins. Where do 
 they originate ? How do they change in size ? Why ? 
 
 6. What are these bubbles ? 
 
 83 
 
84 NATURE STUDY. [October 
 
 7. Hold a thermometer in the steam above the water ; 
 does the temperature vary after boiling begins ? 
 
 8. Is the water still receiving heat from'the flame? 
 
 9. What becomes of this heat ? If you hold your 
 hand near the flame, does the heat continue to increase 
 while you hold it there ? Why does it not in the same 
 way increase the temperature of the water ? 
 
 10. Try boiling alcohol. Does the thermometer, used 
 as before, show the same temperature ? 
 
 CONDENSATION. 
 
 I Where does the water go when the mud dries up ? 
 Is it destroyed ? 
 
 2. How does water change its form when it evapo- 
 rates ? What is its form before it evaporates ? . (Liquid.) 
 Afterward ? (Vapor.) 
 
 3. Is it visible as it disappears from the pan by evapo- 
 ration ? Explain this. 
 
 4. Can it be rendered visible ? What is it then called ? 
 
 5. What change takes place in the vapor when it be- 
 comes visible ? 
 
 6. Explain why it is sometimes foggy in the mornings ? 
 
 7. What causes the fog to disappear ? 
 
 8. Can you account for the formation of clouds? 
 
 9. When are they lowest ? Why ? 
 
 10. What is the history of a drop of rain ? 
 
 DISTILLATION. 
 
 Take a quart or more of the " hard cider " produced 
 by th^ fermentation of yeast. (See Chemistry for Sep- 
 tember.) Put it into a retort with a long neck, or an 
 ordinary bottle with a bent glass tube fitted tightly 
 through the cork. Suspend this in a vessel of boiling 
 
October] PffYSTCS. 85 
 
 water, and conduct the vapor through the tube into a 
 small bottle partly immersed in a vessel of cold water. 
 Distil until about one-third has passed over into the smaller 
 bottle. Redistil until alcohol is obtained sufficiently- 
 pure to show by the flame test. 
 
 1. Why is the smaller bottle irdmersed in cold water ? 
 
 2. Why suspend the other one in boiling water instead 
 of placing it next the flame directly ? 
 
 3. Does the liquid in the flask boil ? 
 
 4. Why not boil the liquid in the flask ? 
 
 S- How is^it that we can gradually separate the alcohol 
 from the remainder of the liquid by this process ? 
 
 6. In how many ways does the alcohol obtained differ 
 from fresh juice of the fruit from which it was distilled ? 
 
 7. Try burning it ; taste it ; note the odor ; allow a 
 little to evaporate from the back of the hand. 
 
 8. Compare with water. 
 
 Books for Reference. Humboldt Library : No; 2, Forms of 
 Water. 
 
(tbemistri?. 
 
 SOLUTION. 
 
 Provide some or all of the following substances : com- 
 mon salt, alum, saltpeter, chalk, washing soda, bichro- 
 mate of potash, blue vitriol, copperas, and prussiate of 
 potash. Each pupil should have a small bottle, about the 
 size of the one-eighth-ounce morphia bottle, which may 
 be procured at a trifling cost of any druggist. Fill each 
 nearly full of cold water and label. Take the tempera- 
 ture of the water, before beginning, with a thermometer. 
 
 1. Drop a small amount of the different substances, 
 finely powdered, into the different bottles. What be- 
 comes of it ? 
 
 2. Drop a small lump in ; does it disappear ? Why is 
 the disappearance more rapid when the substance is finely 
 powdered ? How has the temperature changed ? 
 
 Continue to add the finely powdered substance with 
 constant stirring, until it no longer disappears, but begins 
 to settle on the bottom. Gradually warm the water by 
 placing the bottle on a sand-bath. If not heated slowly 
 the bottle will crack. Test-tubes or thin glass beakers 
 are much better for this purpose. 
 
 3. What effect does the heat have upon the substance 
 at the bottom ? 
 
 4. Add more of the substance until the water boils 
 and no more will dissolve, and then set aside to cool. 
 
 Those substances which disappeared in the water are 
 
Octoberl CnEMtSTkY. §7 
 
 said to be soluble in water. Water is a solvent. They are 
 said to dissolve, and the mixture of water and the dis- 
 solved substance is a solution. 
 
 S. Are all the substances named soluble ? 
 
 CRYSTALLIZATION. 
 
 Pour a little of the above solutions while hot into shal- 
 low dishes, and set aside until the liquid evaporates. Sus- 
 pend a string in the solution remaining in each of the 
 bottles, and observe for a few hours. 
 
 1. How does the form of the solid, which soon appears, 
 differ from what was added to the water ? 
 
 2. Do the crystals which form in the solution differ 
 from those which remain after evaporation from the shal- 
 low dishes ? 
 
 3. Take a small amount of a solution and evaporate it 
 by boiling ; how does the rate of evaporation affect the 
 crystals ? 
 
 4. Are the crystals of each substance al^ alike ? 
 
 5. Solids which are deposited from solution, or which 
 solidify from a melted state in such regular forms, are 
 said to be crystalline. Those which solidify without the 
 crystalline form are amorphous. 
 
fIDeteoroIool?. . 
 
 1. How does the temperature at evening, night, and 
 morning coriipare with that at similar times during Sep- 
 tember ? Will the changes noted in any other column of 
 yQur record suggest the cause for this ? 
 
 2. How does the average temperature of the day differ 
 from that of September ? 
 
 3. What is the direction of the prevailing wind ? Com- 
 pare with September. 
 
 4.. How has the prevailing wind affected the tempera-- 
 ture ? 
 
 5. Has it shown any marked influence upon the barom- 
 eter ? 
 
 6. Has it brought cloudy or clear weather, wet or dry ? 
 
 7. From what direction did the heaviest rain come? 
 From what direction did the greatest number come ? 
 Can you assign reasons for this ? Consult maps and the 
 globe. 
 
 8. What influences, if any, has the nearest mountain 
 range or large bodyof water had upon the temperature 
 and rainfall ? How can you tell what their influence is ? 
 
 9. What kind of cloud has been most frequently noted ? 
 Does the general character of the clouds differ from that 
 of last month ? 
 
 10. Does any particular kind of cloud usually imme- 
 diately precede a heavy rain ? 
 
 11. Have you noticed any fogs ? When are they most 
 dense ? At what time do they disappear ? 
 
.October] METEOROLOGY. H 
 
 12. In what regions are they most dense ? 
 
 13. What was the character of the day and night pre- 
 ceding the fog ? 
 
 14. Does it always follow rain ? 
 
 15. What becomes of it when it is dissipated ? 
 
 STUDY OF SIGNAL SERVICE MAP. 
 
 16. Compare the temperature of the " Low " with that 
 of the " High " area. Can you account for the exceptions 
 to the rule ? 
 
 17. Does the heaviest rainfall, as given on ,the margin 
 of the map, accompany the " Low " area ? 
 
 18. Do the isotherms show as inarked a. deviation 
 from the general direction as they did in September ? 
 
 ' Do the deviations occur in the same regions ? 
 
 19. What is the direction of the wind with respect to 
 the " High " area ? 
 
 20. Where was the storm center during the heaviest 
 storm in this region for the month ? 
 
Hetronomi?. 
 
 1. What change noticed in the length of day and night ? 
 
 2. Compare with the change during September. 
 
 3. Compare with the change in position of the noon 
 shadow. 
 
 4. Are the spaces between two successive marks of 
 the same length as they were in September for the same 
 period of time ? Can you show why there is variation ? 
 
 5. Using the globe arrd sun, explain the differences 
 discovered- 
 
 6. What time elapses between two successive full 
 moons ? 
 
 7. By means of a globe and sun, and another object to 
 represent the moon, show what the relative position of 
 the three bodies is when the moon is full. 
 
 The constellations to be observed are all of thos'e given 
 in preceding month, and in addition : Perseus, Androm- 
 eda, Serpentarius. Note the change in position, since 
 last month, of the different constellations. 
 
 How can we account for it ? 
 
(BeoQrapb^. 
 
 DRAINAGE. 
 
 GENERAL CONDITIONS. 
 
 T. What becomes of the water that falls as rain upon 
 the land ? Mention three ways by which it is removed 
 from the surface. (See Physics and Geology for Octo- 
 ber.) 
 
 2. What determines the direction of the flow of waters 
 from the land ? 
 
 3. What conditions determine its velocity ? 
 
 4. What conditions affect the size of a river, (a) its 
 length, (J)) its volume of water ? 
 
 NORTH AMERICA. 
 
 1. Which ocean, with its arms, receives the larger 
 amount of water from the continent of North America? 
 
 2. What does this indicate as to the number of the 
 great slopes of the continent ? 
 
 3. Where do they show the line of the great continen- 
 tal water-parting to be ? 
 
 4. By modeling, represent the continental outline with 
 this great water-parting and the two slopes. 
 
 5. Do the rivers in the eastern slope indicate the posi- 
 tion of a secondary water-parting ? What is its direc- 
 tion and position ? Represent the two slopes from this 
 water-parting. 
 
92 NATURE STUDY. [October 
 
 6. Judging from the direction of the rivers in the 
 northern slope, where are the great depressions ? 
 
 7. Are there any minor divisions in the slope, as indi- 
 cated by rivers ? 
 
 8. In the southern slope of the continent, do the 
 rivers indicate any other water-parting ? 
 
 9. Where is this, and what is its direction ? Indicate it 
 in the model. 
 
 10. What directions do the rivers flow from this water- 
 parting ? 
 
 11. Where is the lowest line between the great conti- 
 nental water-parting and the last one found ? 
 
 12. Study the course of the rivers in the southern conti- 
 nental slope between these two water-partings ; what must 
 be the general form and character of the surface of this 
 region ? 
 
 13. What things contribute to form the great rivers of 
 this region ? (See Studies of Signal Service Maps.) 
 
 14. In the eastern half of the Mississippi basin, is there 
 any well-marked transverse water-parting ? 
 
 15. Compare the two halves of the basin in this re- 
 spect. 
 
 16. Since no great river systems are found on the 
 coast slopes, what must be the character of those slopes ? 
 What is their direction from the water-partings ? 
 
 17. Make a complete model of the continent, showing 
 the water-partings and slopes, the lines of lowest depres- 
 sion, the chief rivers and lakes. 
 
 18. In what way did the continental slopes affect the 
 settlement of the country ? 
 
 19. Why were the earliest settlements in the interior 
 made along the northern border of the United States ? 
 
 3o. What advantages did the early French routes into 
 
October] GEOGRAPHY. 93 
 
 tlie interior possess over those of the English and Span- 
 ish ? 
 
 21. In what way have the different slopes affected the 
 occupations of the people ? 
 
 22. Why has the Atlantic coast slope always been a 
 manufacturing region ? 
 
 23. Why^does New York excel Philadelphia in trade 
 with the interior ? 
 
 24. What has determined the location of the great 
 cities of the Mississippi basin ? 
 
 25. What natural features have fixed the chief routes of 
 commerce ? (The line where the slopes meet at their 
 lower edges or borders.) 
 
 26. How do the continental slopes affect the commerce 
 between the North and South ? 
 
 27. How do the slopes affect the commerce between 
 the East and West ? 
 
 28. How have the great slopes affected the develop- 
 ment of the Pacific coast region ? 
 
 29. How have the continental slopes affected the com- 
 merce between the Atlantic and Pacific coasts ? 
 
 Books for Reference. How to Study Geography, Francis W. 
 Parker ; Earth and Man, Guyot. 
 
<5eoI09l?. 
 
 EROSION AND SEDIMENTATION. 
 
 Select some small stream that may be studied for some 
 distance along its course. The small gullies formed by 
 a heavy shower will answer very well. Certain river val- 
 leys in northern Italy that were once partially filled. with 
 glacial drift now abound in stone-capped clay pillars 
 many feet in height. These have been formed by the 
 rain wearing away the earth around the stones while that 
 immediately under them was protected from its action. 
 Similar pillars in miniature may be seen after a hard rain 
 on any exposed clayey surface where thjere are small bits 
 of stone. The height of the pillars indicates roughly the 
 amount of soil torn away by the rain. The sun then 
 dries them out, and, crumbling down, they are soon again 
 at a common level with the surface. Trifling as this pro- 
 cess may seem, the amount of soil thus beaten up and re- 
 moved by the rain, in the course of a year, must be 
 enormous. 
 
 1. How does a heavy rain affect the surface of the 
 ground ? How do you account for any minute elevations 
 that remain standing after a hard rain ? 
 
 2. What causes a stream to be crooked ? Does it ever 
 tend to straighten its channel ? How ? 
 
 3. In what part does it cut the deepest channel ? 
 
 4. In what part the widest ? 
 
 94 
 
October] GEOLOGY. 9S 
 
 5. Upon what does the swiftness depend ? 
 
 6. When two branches unite, is the single channel 
 thus formed as largeas that of both branches put to- 
 gether ? 
 
 7. Can you notice any difference in the character 
 of the sediment in different parts of the course ? Dip up 
 a little of the water in different places and allow it to 
 settle. 
 
 ,8. In what part of the course of the stream do you find 
 the largest pebbles ? 
 
 9. Where are they most rounded and worn ? 
 
 10. What determines where in the course of a stream 
 they shall be deposited ? Study the order of deposition 
 in a pool or lakelet. As a further illustration, shake up 
 different kinds of material in a glass jar, and allow them 
 to settle. 
 
 11. In what part of the stream's course is the finest mud 
 dropped ? 
 
 12. Does the stream build new material along its banks ? 
 Under what conditions ? 
 
 13. Cut down through some of the material thus de- 
 posited, and note the arrangement ; is there any regu- 
 larity ? 
 
 14. Examine the material deposited at the mouth of the 
 stream ; how is it arranged ? 
 
 15. Under what conditions will it not be deposited ? 
 
 16. What are some of the things which assist the stream 
 in widening its channel ? What influence does drift have 
 upon it ? 
 
 17. What causes the formation of waterfalls ? 
 
 18. What determines whether the descent from a higher 
 to a lower level shall be by a cascade or by rapids ? 
 
 ' 19. Study the face of some cliff, a railroad cut, the sides 
 
96 NATURE STUDY.' [October 
 
 of a trench, or newly made excavation ; is there evidence 
 of deposition from water ? 
 
 20. Can you tell whether it was deposited by running 
 or still water ? 
 
 21. Can you see. any reason why certain rocks are to be 
 found in strata ? 
 
 22. Can you tell if the rocks that dip were deposited 
 in that position ? Compare with the depositions in the 
 glass jar. (See 10.) 
 
 23. If not deposited thus, what evidence is there that 
 they were uplifted ? 
 
 24. Did the upheaving force act slowly for a great 
 length of time, or rapidly for a shorter period ? 
 
fllMneralog^. 
 
 Gather a handful of coarse sand. Put it in a jar and 
 thoroughly wash by shaking it up with water repeatedly, 
 until freed from silt. 
 
 1. Examine some of the grains under a lens ; can you 
 find any. crystals ? 
 
 2. Are they entire or fragmentary ? 
 
 3. Ho.w many different kinds can you find ? 
 
 4. Can you tell where the sand came from ? 
 
 5. Examine particles of the soil and compare with a 
 bit of the powdered rock which underlies it ; are they 
 the same ? 
 
 6. Has the soil been formed by the weathering or rot- 
 ting of the underlying rock ? 
 
 7. What other agent has aided in the soil formation ? 
 
 8. Examine the rough surface of a piece of marble ; 
 can you see any crystals ? 
 
 9. In the same way examine a piece of granite ; how 
 many different minerals does it contain ? - 
 
 10. Coarsely powder a small piece ; are the fragments 
 crystalline ? Which is the softest ? Which the hardest ? 
 Granite is made tip of quartz, feldspar, and mica ; the 
 feldspar decomposes and becomes clay. What becomes 
 of the quartz ? 
 
There is hardly a more useful auxiliary to the science 
 work which relates to animal life than an aquarium. If 
 it be possible to have a strong metal-framed one. connect- 
 ed with a steady water supply, it will save much trouble, 
 but one may be managed very well without such con- 
 veniences. If no connection with pipes can be made, it 
 it better to have several of medium size than to have one 
 large one. Fish globes, eight or ten inches in diameter, 
 are inexpensive and will be found very useful. 
 
 A small aquarium may be mad;2 thus : use an inch 
 board one foot wide and one foot long for the bottom, 
 and two boards of the same thickness and width, ten 
 inches high, for the ends. Three-eighths of an inch from 
 the edge on either side, with a saw, make a groove one- 
 quarter of an inch deep, and wide enough to receive 
 loosely double strength glass. Groove the end boards 
 and fasten them to the bottom with screws so that the 
 grooves will exactly match. I*artially fill the grooves 
 with soft putty, or better, aquarium cement, and press 
 into each side a pane of glass. By making the bottom 
 board eleven and one-half inches long, an ordinary ten 
 by twelve window pane will be the proper size. When 
 the glass is pressed to the bottom of the groove, draw the 
 two ends in at the top until the glass is held firmly and 
 then fasten them in place by narrow strips of wood, 
 one on each side of the tank, placed on top of the glass 
 and screwed to the end pieces. These strips also pro- 
 
November] ZOOLOGY. 99 
 
 tect the hands from injury while working with the speci- 
 mens in the aquarium. Before filling with water, the 
 inner surface of the bottoni and e"nds should be well 
 rubbed with oil or paraffine and the grooves inside the 
 glass well packed with putty. The bottom should be 
 covered with an inch or two of sand and coarse 
 gravel. 
 
 Two or three of this size will enable one to preserve 
 safely a large variety of specimens, and sufficient in 
 amount to keep up an interesting study of animal life 
 throughout the winter. Indeed, if the supply falls short, 
 they may be restocked at any time of the year. By drag- 
 ging the bottom or edges of a pond or ditch, which is 
 covered with leaves and grass, with a hand rake, using a 
 net, one may usually in the midst of winter gather an 
 abundance of minnows, tadpoles, snails, crawfish, frogs 
 water-beetles, etc. 
 
 GENERAL OBSERVATIONS. 
 
 1. Are any birds to be found at this time ? Are the 
 birds that have migrated superior to those that remain in 
 intelligence ? 
 
 2. Are they winter residents ? 
 
 3. Have they been here all the year or have they come 
 from some other locality ? 
 
 4. What is their food ? How do they find protection 
 from storms ? 
 
 5. Where do they stay at night ? 
 
 6. Is their winter garb different from that of summer ? 
 
 7. Are they mated, in flocks, or solitary ? 
 
 8. Look for insects under stones, boards, leaves, etc. 
 Have they lined their nests in any way as a protection 
 against the cold ? 
 
100 NATURE Study. [November 
 
 9. If they are not active keep them for a short time 
 in a warm room. 
 
 10. Do they show signs of life ? 
 
 11. In the same way, search for earthworms. 
 
 12. What substitute have these animals for migration ? 
 
 13. What do they do for food ? 
 
 14. Animals lying through the v/inter in a dormant 
 state are said to hibernate. 
 
 15. Pat a common mud-turtle in a box of wet sand 
 and cover loosely with a lid. Keep the sand wet. 
 
 16. Note the time when he disappears ; he will prob- 
 ably not be seen again for months. 
 
 17. How do you think the chances for life of a hiber- 
 nating animal compare with one that is migratory. 
 
 18. Why does the animal hibernate wh^n kept in a 
 warm room in winter time ? Does the animal display 
 intelligence in hibernating ? 
 
 ANIMAL COVERINGS AND WARMTH. 
 
 1. What changes do we make in our clothing as winter 
 approaches ? In material ? Color ? Thickness? Tex- 
 ture ? 
 
 2. How do the brute animals make similar prepara- 
 tion ? 
 
 3. Is the winter plumage of birds the same as that of 
 summer ? 
 
 4. How do birds preen their feathers ? Why ? 
 
 5. How are the coverings of water-fowl especially 
 adapted to their mode of life ? 
 
 6. Study the arrangement of the feathers on a bird ; a 
 pigeon or sparrow may be readily obtained for the pur- 
 pose. Are the feathers distributed evenly over the 
 body? 
 
November] ZOOLOGY. tot 
 
 7. Is there any obvious advantage in the manner in 
 which the feathers are distributed ? 
 
 8. Mention the uses you can see for feathers ? 
 
 9. What animal can you name that is covered with 
 fur ? Name one covered with hair ? What difference 
 is there between fur and hair ? Examine a dog and a 
 cat. 
 
 10. Can you suggest any reason why one animal is pro- 
 vided with fur and another with hair ? 
 
 11. Which is the better protection against injury? 
 Which is the warmer covering ? 
 
 12. Where are fur-bearing animals found ? Where are 
 those with a hairy covering found ?■ Compare wool with 
 both hair and fur ? 
 
 13. Read something of the history and habits of the 
 fur and wool bearing animals. 
 
 14. Study the scales of a fish and snake ; what is their 
 chief use in each case ? 
 
 15. Do the coverings of fishes and snakes change in 
 any way with the seasons ? 
 
 16. If possible, secure a snake skin that has been shed 
 and examine it closely ; how does the snake get out of it ? 
 Are the scales shed ? 
 
 17. Is the right side out ? Note the transparent cover- 
 ing that was over the eye. 
 
 18. How does the covering of the turtle differ from 
 that of both the snake and the fish ? 
 
 , igi Do insects have skins ? How does the outside of 
 an insect's body differ from most other animals studied ? 
 
 20. What peculiarity in the covering of a crawfish ? 
 What is its most important use ? 
 
 21. Can you see how it is possible for the animals 
 which have such hard coverings to grow ? 
 
I02 NA7'URE STUDY. [November 
 
 22. How do the different modes of life of the various 
 animals observed correspond to their coverings ? 
 
 THE SKIN OF THE HUMAN BODY. 
 
 1. Compare the skin on the back of the hand with that 
 on the palm in color, thickness, sensitiveness, and mark- 
 ings. 
 
 2. Why is the greater thickness on the palm ? 
 
 3. On what other parts of the body is the skin similar 
 to this ? Why ? 
 
 4. What is the effect of manual labor on the skin in the 
 palm ? 
 
 5. Is there any difference in the causes which operate 
 on the palm and on the sole of the foot ? 
 
 6. What causes the creases in the palm ? 
 
 7. Note the short hairs covering the back of the hand ; 
 examine with small magnifying glass. At the root of each 
 hair is a small oil gland which pours out upon the surface 
 a minute quantity of oil. Notice the softness and flexi- 
 bility of the skin. 
 
 8. When is it ', that the skin on the hands becomes 
 harsh and chapped ? 
 
 9. How is oil affected by cold weather ? How must it 
 affect the flow from the glands in the hands ? 
 
 10. How do the hands feel after having had them in 
 soap-suds ? What must be the effect of the soap on the 
 oil? 
 
 11. Why should the skin be wiped dry after washing^ 
 
 12. What is the best way to prevent the hands from 
 becoming chapped ? 
 
 13. What would you suggest as the natural remedy ? 
 The outer layer of the skin which sometimes may be 
 
 rubbed up as wliite scales, and which forms the clear skin 
 
November] ZOGLOGY. 103 
 
 in a blister, is the cuticle or scarf skin. As it dies and 
 is worn off it is replaced by the true skin underneath. 
 When dry, it cracks and exposes the sensitive layer lying 
 under it. 
 
 A small cake of pure mutton tallow rubbed oyer the 
 hands at night is a simple and effective remedy. It 
 should not be smeared on in great quantity. Nature 
 never oils the skin in that way, and we should imitate her 
 in this respect. 
 
 14. What is perspiration ? Is it pure water ? 
 
 15. What causes tend to increase perspiration ? To 
 diminish it ? 
 
 16. Passing outward through the skin, and opening at 
 its surface, are very many minute tubes that convey the 
 perspiration from the sweat glands ; these are situated in 
 the deeper layers of the skin. The openings of these 
 glands may be seen through a magnifying glass in rows in 
 the palm. 
 
 The sweat glands in health are continually throwing off 
 from the body waste matters which are carried to them 
 by the blood. 
 
 17. How must the heat of the body be affected by the 
 evaporation of perspiration from its surface ? 
 
 18. Do you become warmer or cooler when you per- 
 spire freely. Since the skin thus assists in maintaining a 
 proper heat in the body, it is a heat regulator. 
 
 19. Rub a little oil briskly on the hand ; what becomes 
 of it ? Has it evaporated ? 
 
 20. Why is it that liniments may be applied to the 
 skin for ailments that lie deeper, as in case of a sprain ? 
 The skin is an organ of absorption. 
 
 21. On what part of the body is the skin most useful 
 in giving us the sense of touch ? 
 
104 NATURE STUDY. [November 
 
 22. The sensitiveness of the skin in different parts may 
 be tested by using a pair of dividers with sharp points 
 thus : close the eyes and allow some one to touch the 
 skin in various places, now with the single point, then 
 with the double point. Find where you can distinctly 
 distinguish the two points when they are closest together. 
 
 23. Try in this way the palm, back of hand, cheek, 
 tongue, lips, back of neck, arm, ear, etc. 
 
 24. How many important uses 'have we found for the 
 skin ? ,, 
 
 25. Examine one of ^he finger-nails. Note the opaque 
 area near the base ^Ued the lunula, and also how the 
 skin is attached around the inner end. 
 
 26. Does, the skin grow fast to the edge of the 
 nail ? 
 
 27. Why does the skin sometimes break and peel back- 
 ward from the base of the nail ? 
 
 28. To prevent this, loosen the skin by running around 
 the edge the dull point of a knife. 
 
 29. In what way are the nails most useful ? What 
 happens if they are allowed to grow too long ? If 
 trimmed too closely ? How does the care of the nail 
 affect the shape of the finger-tips ? 
 
 30. How does biting the finger-nails spoil them ? 
 
 31. Why is a knife better than scissors for trimming 
 them ? The nail is made of thin layers, and scissors, es^ 
 pecially dull ones, tend to separate them. 
 
 32. Of what use to us is the hair on the head? 
 
 33. Can you give a good reason for brushing and 
 combing it ? 
 
 34. Note the white powdery flakes that may be some- 
 times brushed from the head. Where do they come 
 from ? 
 
November] ZOSLOGY. 105 
 
 35- Compare these with the cuticle which^ may be 
 rubbed from the back of the hand. 
 
 36. What gives the softness and flexibility to the hair ? 
 
 37. What is the effect of using soap and water upon it? 
 Why is it so ? 
 
 38. Why is it necessary to wash the hair? If the 
 scalp is healthy no oil is needed ; and if it is not, oil will 
 do but little good. Treat the scalp much the same as 
 you do the skin on other parts of the body. 
 
 39. How many distinct uses of the skin maybe named ? 
 
 40. How may it best be cared for as an organ of pro- 
 tection ? Contrast the effects of indoor and outdoor 
 occupations upon it. What are the effects upon the skin 
 of bodily exercise in fresh air ? 
 
 41. How may its usefulness as an organ of touch be 
 increased ? 
 
 42. In what occupations is a refined sense of touch 
 necessary ? Of what use is it to a physician ? How do 
 the blind utilize it ? 
 
 43. Test yourself as to this sense. Can you distinguish 
 by touch a one-cent piece from a dime ? A five-cent 
 piece from a two-cent piece ? Sugar from salt ? Salt 
 from sand ? Can you distinguish flannel from heavy cot- 
 ton cloth ? Printed from unprinted paper ? 
 
 44. How is the usefulness of the skin promoted by 
 bathing ? 
 
 45. How does the work of the skin necessitate frequent 
 change of clothing ? 
 
 Books for Reference. .As a text-book, Martin's Human Body. 
 Humboldt's Library, No. 4, Man's Place in Nature. See also the 
 Nos. previously recommended in work for September and October, 
 
Botany. 
 
 The activity of plant life outdoors has ceased, and 
 but little can be done with the study this month except 
 to examine the dormant condition of those plants which 
 live through the winter, and to note the provisions made 
 for the succeeding season by those that do not. The 
 nice adaptation of the plants to their changed environ- 
 ments is the chief point to be observed. 
 
 1. Have the plants completed their preparation for 
 winter ? 
 
 2. Can you find any that continue to grow until the 
 leaves fall ? 
 
 3. Do the first frosts kill any of the newly grown 
 twigs ? Examine as many different kinds of trees as 
 possible. 
 
 4. What changes have the new twigs undergone since 
 summer ? 
 
 5. Can you find any plants that have been entirely 
 killed? 
 
 6. How will such plants be reproduced next season ? 
 
 7. How does the number of seeds produced by plants 
 that are killed each year by frosts compare with the num- 
 ber produced by plants that live from year to year ? 
 Which class of plants seems to have the better mode of 
 scatteringits seeds? Take plenty of time in working up 
 this topic so that a large number of examples can be 
 cited by the pupils. 
 
 8. Are there any seeds to be found ? Can you find 
 
November] BOTANY. lo) 
 
 any which by some means have been planted ? Re- 
 move a small pan-full of earth to the warm school-room 
 and see if any self-planted seeds will grow. 
 
 9. Can you find any plants which came from the seed 
 last spring that have been entirely killed by the frost ? 
 Such plants. are called annuals. 
 
 10. Plants which live over from year to year are called 
 perennials. 
 
 11. Look through the garden for plants whose roots 
 or underground stems are still alive, but whose tops may 
 be dead. Do you know what the entire life history of 
 such a plant is ? Examples, parsnip and turnip. Such 
 plants are called biennials. 
 
 References. See October. 
 
If)b^sic0. 
 
 HEAT. 
 
 In the experiments to be performed, it is the intention 
 to have the pupils prepare' the apparatus under the di- 
 rection of the teacher and do all the work. 
 
 The teacher must see that the directions are closely 
 followed that the conditions may be as nearly perfect as 
 possible. Ideal results are not to be expected, but for 
 what is lost in this respect, compensation may often be 
 found in a close study of the disturbing elements which 
 rendered them inaccurate. Interpretation of the results 
 of all the experiments must be insisted upon, and con- 
 cise statements, together with descriptions of the appa- 
 ratus, in many cases accompanied with drawings, should 
 be .required. 
 
 In some instances, teachers fail because they do not 
 allow the pupils sufficient time in which to prepare their 
 apparatus. With the mind fixed upon an expected result, 
 they too often force the experiment regardless of proper 
 precautions which should have been taken. In describing 
 an experiment 'the pupil should always be required to 
 state what precautions are necessary to be observed. 
 There is as much for the pupil, often, in the careful prep- 
 aration and manipulation of the apparatus as there is in 
 the outcome of the experiment itself. 
 
 In the following work, witli^a little care on the part of 
 
November] PHYSICS. tOQ 
 
 the teacher, a good deal may be accomplished in the cul- 
 tivation of a " temperature sense " in the pupil. While 
 it does not rank high among the senses in usefulness, and 
 in most persons it is but poorly developed, it should not 
 by any means be neglected. With but little practice the 
 pupils will be able to judge, with considerable accuracy, 
 of the different degrees of temperature of water between 
 the freezing point and that of 130° or 140° Fahren- 
 heit. 
 
 The central thought to be developed in these lessons 
 on heat is, that heat is energy which expresses itself in 
 different ways owing to the manner in which it is directed 
 and to the medium employed. Almost the only expres- 
 sion with which the pupils are familiar is that of temper- 
 ature, and that heat should be able to perform work 
 without increasing the temperature is something that is 
 hard to get them to realize. The fact, however, that 
 heat continually passing into a vessel of melting snow or 
 ice does not raise the temperature while the ice is melting 
 is enough to start them to thinking in an intelligent way 
 upon the subject. The uniform temperature of water 
 after it has been raised to the boiling point, although heat 
 is constantly added, is illustrative of the same point. To 
 the question as to what this excess of heat which passes 
 into the water, in either case, does, the pupil can hardly 
 find a wrong answer, if cautiously and properly directed. 
 
 RADIATION, ABSORPTION, AND REFLECTION. 
 
 1. Heat an iron rod or bar in a flame till red hot, re- 
 move, and hold the face or hand near it on different 
 sides. What is noticed as to the direction in which heat 
 passes off ? Heat thrown from a body thus is said to be 
 radiated. 
 
no NATURE STUDY. [November 
 
 2. What becomes of the heat radiated from a body ? 
 Is it destroyed ? 
 
 3. Does the rod radiate all its heat ? When will radia- 
 tion cease ? 
 
 4. By what contrivances are rooms heated by radia- 
 tion ? 
 
 5. Why does the earth become cooler after sunset ? 
 
 6. Which becomes cold faster, the land or the water? 
 
 7. Why is it that dew forms at nightfall ? 
 
 8. Why is the formation of dew dependent upon the 
 clearness of the night ? Consult your Meteorological 
 Record for the facts upon which to base your answer. 
 
 9. Compare and contrast with (8) the conditions under 
 which fog forms. 
 
 10. When any body is held near a warmer one, how is 
 the former affected by the latter ? Anything so warmed is 
 said to get its heat \rj absorption. 
 
 11. Is the absorption of heat affected by the smooth- 
 ness or roughness of the surface of the body ? 
 
 12. Does color affect the result ? When opportunity 
 offers, spread two small squares of cloth, one white and 
 the other black, upon snow in the sunshine ; after a 
 time notice the rate of melting underneath each one. Try 
 different materials of each color ; is the rate of melting 
 dependent upon the color or material and texture of the 
 cloth ? 
 
 13. Heat which strikes a body and is again thrown off 
 is said to be reflected. 
 
 14. Are good radiators also good reflectors ? 
 
 15. Are good radiators good absorbers ? 
 
 16. Which of the above qualities should a good stove 
 possess ? 
 
 17. Should a stove be kept with a brightly polished 
 
November] PHYSICS. m 
 
 surface ? Should the surface be smooth or broken by 
 ornamentation ? 
 
 TEMPERATURE. 
 
 1. Provide a small vessel of water and a thermometer. 
 The water should have a temperature of 50° or 60°. 
 Hold the fingers in this till familiar with the sensation. 
 Place the thermometer in the vessel and note the temper- 
 ature. 
 
 2. Apply heat until twenty degrees hotter, and again 
 let the pupils test with the fingers and then measure with 
 the thermometer. In this way, test with the hand and 
 measure with the thermometer until the fingers can be 
 held in it but a few seconds only. 
 
 3. Begin again with the temperature first taken and by 
 adding snow or ice reduce to the freezing point, testing 
 with the fingers and reading the thermometer as before. 
 
 4. Repeat these experiments, changing the temperature 
 ten degrees each time instead of twenty. 
 
 5. After holding the fingers a short time in ice water, 
 dip them in water having the temperature at which you 
 began ; does it feel warmer or cooler than before ? The 
 pupil should test with his fingers and express his judg- 
 mentas to the temperature in each case before using the 
 thermometer. 
 
 6. Why is testing the temperature in this way with the 
 fingers likely to be untrustworthy? 
 
 7. Note the temperature of the school-room ; it should 
 
 be about 68°. Compare with that of a hall-way. Daily 
 
 practice should be given in judging the temperature of 
 
 the room. 
 
 EXPANSION. 
 
 I. Fasten one end of a small iron rod or wire, a foot 
 long, tightly in a small support of some kind. Against 
 
112 NATURE STUDY. [November 
 
 the free end arrange an index finger in such a way that 
 it will move over a dial. The index should be several 
 inches long and the wire should rest against it near the 
 pivot. 
 
 2. Apply heat to the rod throughout its length ; note 
 the movement of the index. What does its movement 
 indicate ? 
 
 3. Withdraw the heat ; does the rod still rest against 
 the index ? 
 
 4. Substitute a brass rod for the one of iron and note 
 the movement of the index. 
 
 5. Cut or punch a hole in a piece of tin large enough 
 to just allow a rod to pass through it smoothly. Heat 
 the rod and try passing it through the hole. What does 
 this indicate? Cool the rod and try again. 
 
 6. Can you see any reason why a blacksmith should 
 heat the tire of a wheel before putting it on ? 
 
 7. Why is there a space between the ends of the rails 
 in a railroad ? 
 
 8. Why heat the bolts and rivets used in putting to- 
 gether the parts of iron bridges and boilers ? 
 
 9. Allow each pupil to fill a small bottle level full of 
 water which has been colored with a little indigo or m\. 
 Pass a glass tube a few inches long and of small bore, say 
 one-eighth of an inch, just through the cork ; it should 
 not project below the under surface of the cork. Press 
 the cork tightly into the bottle and the water will,rise in 
 the tube ; see that no bubble of air rests underneath the 
 cork and that none are clinging to the inside of the bottle. 
 The water should stand in the tube so as to be visible 
 above the cork, and the point to which it rises should be 
 marked. This is easily done by slipping down over the 
 tube a small piece of paper. 
 
November] PHYSICS. I13 
 
 10. Place this in a shallow pan containing sand, and 
 heat gradually over the alcohol lamp. 
 
 11. Can you notice any movement of the water in the 
 tube ? Why is the tube used ? 
 
 12. What is the effect of heat upon the water? 
 
 13. Make a drawing of the apparatus used and explain 
 why each successive step is taken in its arrangement. 
 
 14. Using the same apparatus, place the bottle in a 
 vessel containing snow or ice mingled with salt. Watch 
 sharply the column of water in the tube. 
 
 15. Compare its movements with those when the bottle 
 was heated. 
 
 16. In order to test the temperature, one bottle with a 
 wide mouth should be prepared with the tube and also a 
 thermometer through the cork. At what temperature 
 does the water begin to rise in the tube ? Does it expand 
 beyond its original volume ? 
 
 17. From these two experiments can you think of what 
 changes and movements the water in a pond must undergo 
 in being frozen ? 
 
 18. Why does ice form at the top and. not at the bottom 
 of a pond or stream ? 
 
 19. What would likely be the result if the ice should 
 begin to form at the bottom ? 
 
 20. Prepare the bottles again as above, but fill them 
 only about half full of water and push the tube through 
 the cork until it reaches nearly to the bottom. 
 
 21. Clasp the upper part of the bottle in the hands and 
 watch the tube. 
 
 22. Compare carefully the conditions of this experi- 
 ment with those in the last. What essential difference 
 between them ? 
 
114 MATURB study. [November 
 
 23. Heat the bottle, as before, over a lamp ; account 
 for the result observed. 
 
 25. If possible, procure a bladder or a small rubber 
 bag partially filled with air ; warm it gently and account 
 for the result. 
 
 Books for Reference. — Humboldt Library, No. 120. The, 
 Modern Theory of Heat; and The Sun as a Storehouse of Energy. 
 
Cbemistr?. 
 
 In this and other science work it will sometimes be 
 necessary to have a means of getting a strong heat without 
 smoke. If gas is at hand it is best to procure a Bunsen 
 burner and attach it to a jet with a rubber tube. An 
 alcohol lamp, however, will mak& a good substitute. To 
 make one of these, take a small bottle and perforate the 
 cork, making a round opening three-eighths of an inch in 
 diameter. With a small piece of tin make a tube an inch 
 or two long that will tightly fit the hole through the cork, 
 allowing it to project a short distance above. The seam 
 of the tube need not be soldered. Roll a small flat 
 lamp wick tightly and pass it through the tube. A large- 
 sized thimble may be used as a cap for extinguishing the 
 flame and to prevent waste of alcohol when not lighted. 
 The cork should rest loosely in the bottle when in use. 
 A much better lamp is made by using a metal-capped 
 tooth-powder bottle that may be bought of any druggist 
 for five cents. This equals any alcohol lamp of its size 
 that is made specially for the purpose, and it is much 
 cheaper, and will answer all purposes where heat is re- 
 quired in performing the experiments suggested in this 
 book. 
 
 1. Take a small stick of wood and cut it into fine 
 pieces ; set fire to another similar one and let it be con- 
 sumed. Watch closely the changes taking. place. 
 
 2. How has the wood been changed in the first in- 
 stance ? Are there any changes in amount ? 
 
 "5 
 
Ii6 NATURE STUDY. [November 
 
 3. Has there been any change whatever in the substance 
 of the wood ? 
 
 4. What was the first change noticed in the burning 
 wood ? Note the charring. 
 
 ^ 5. Does anything remain after burning has ceased ? 
 What is it ? 
 
 6. Does it in any way resemble the wood ? 
 
 7. Is there in what remains either as great bulk or 
 weight as there was in the wood>? 
 
 8. What has become of the part that has disappeared ? 
 
 9. Allow the smoke to strike a piece of porcelain or 
 glass ; what collects on the surface ? 
 
 10. Does the soot in any way resemble the wood ? 
 
 11. Was it a part of the wood? 
 
 12. Hold the flame of an alcohol lamp under and 
 near the soot on the plate ; what becomes of it ? Is it 
 totally consumed ? 
 
 13. What is the greatest difference, in result, of the 
 above operation on wood ? 
 
 14. In the first instance there -wsiS a. physical change ; 
 in the second a chemical change. 
 
 15. Try lowering the lighted stick into a wide-mouthed 
 bottle ; try again with a bottle or jar of larger size ; com- 
 pare the burning under such conditions with those in the 
 first instance. 
 
 16. What conditions seem to be necessary for the 
 burning of the wood ? 
 
 17. Is the air in the bottle changed when the stick is 
 burned in it ? 
 
 18. Pour into a clean bottle half an inch of lime- 
 water and shake it ; does it change ? 
 
 19. Now burn a match in the bottle and shake again ; 
 is the lime-water changed ? 
 
November] CHEMISTRY. 1 1? 
 
 20. Does this recall ,the results of any experiment of 
 a previous month ? 
 
 21. Drop a piece of marble into a small bottle of strong 
 vinegar or into water mixed with hydrochloric acid ; how 
 does the action differ from what takes place when it is 
 put into water ? (See Chemistry for October.) 
 
 22. Use a piece of limestone in place of the marble ; 
 describe closely what occurs. 
 
 23. What do the bubbles contain ? Lower a lighted 
 match into the bottle. 
 
 24. By means of a bent tube through the cork, draw 
 some of the gas formed out in.to a small amount of lime- 
 water ; do the results with the lime-water and match re- 
 call any previous experiments .■' This is a test for car- 
 bon dioxide gas. 
 
 25. What tests proved it to be different from air ? In 
 wliat respects is it like air ? 
 
 26. Place in a Florence flask or pint bottle a handful 
 of pieces of marble, cover them with water and add 
 hydrochloric acid till gas comes off freely. Through a 
 bent glass tube in the cork convey the gas to the bottom 
 of another wide-mouthed bottle or a beaker. 
 
 27. After a few mirtutes, with a movement as of pour- 
 ing, invert the beaker over a burning taper or match ? 
 How do you account for the result ? 
 
 28. Why is it possible to collect this gas in an open 
 beaker as we did ? Why is it possible to pour it like 
 water ? 
 
 29. When the bubbling ceases, pour off the liquid and 
 dry the solid that remains ; does it differ from what was 
 used originally ? 
 
 30. Will acid act upon it again as it did at first ? 
 
Il8 NATURE STUDY. [November 
 
 31. Try the vinegar with chalk or limestone or mar- 
 ble that has been mixed with water. 
 
 32. Have the substances in the above experiments 
 undergone physical or chemical change ? 
 
 33. Take a small amount of sulphur and mix 
 thoroughly with about the same quantity of iron filings ; 
 can you distinguish the two substances in the mixture ? 
 
 34. Can you separate the two substances ? Blow upon 
 the heap. 
 
 35. Pass a magnet back and forth near the mixture ; 
 what is the result ? 
 
 36. Make another similar mixture of sulphur and fil- 
 ings in a cup ; warm gradually over the burner. 
 
 37. Watch closely and describe the changes that take 
 place ? 
 
 38. After the action ceases, examine the substance 
 formed and compare with the original materials. 
 
 39. Can you distinguish the sulphur ? How does it 
 differ from the filings ? The new substance thus formed 
 is called iron sulphide. Instead of writing the word iron 
 in full, the symbol Fe is generally used, and instead of 
 the word sulphur the symbol S is written. Iron sulphide 
 has for its symbol, Fe S. In the first instance the iron 
 and sulphur formed merely a rnixture ; in the second a 
 combination. What is the difference ? 
 
 40. Which experiment with the filings and sulphur 
 more closely resembles that with the acid and marble ? 
 
 41. In what important particular are they different ? 
 
 42. In how many of the experiments performed could 
 you distinguish new substances that were formed ? 
 
 43. What were the tests used which proved their pres- 
 ence ? 
 
November] CHEMISTR Y. 1 1 9 
 
 44. How does the new substance which was formed in 
 the bubbles of vinegar differ from the Fe S in the last ex- 
 periment ? 
 
 Books for Reference. Remsen's Introduction to the Study of 
 Chemistry. 
 
fll^eteoroIogl?♦ 
 
 I. How does the mean temperature for the first week 
 compare with that of the first week in October ? What 
 causes the difference ? 
 
 , 2. Is the direction of the prevailing wind the same 
 as it was for October ? Is it a cold or a warm wind ? 
 
 3. How can you account for its direction ? 
 
 4. What wind is accompanied by a clear sky ? How 
 does this wind affect the temperature ? 
 
 5. What wind has accompanied the rains? Are the 
 rains more or less frequent than they were in the preced- 
 ing months ? 
 
 6. How does the amount of rainfall compare with that 
 of the preceding months ? 
 
 7. What is the most common form of cloud observed ? 
 
 8. How have they changed in character? Are they 
 higher or lower than they were in September ? 
 
 9. Which is the more common this month, frost or 
 dew ? 
 
 10. What is the character of a night preceding a frost ? 
 
 II. Does the frost form upon all objects outdoors ? 
 
 12. How does a windy night affect the formation of 
 frost ? A cloudy night ? 
 
 13. Examine some frost crystals under a lens. 
 
 14. Are they uniform in shape and size ? Are frost 
 crystals frozen drops of dew ? 
 
 15. What difference is therebetween the conditions for 
 forming dew and those for forming frost ? In what re- 
 spects are they the same ? 
 
November] METEOROLOGY. 121 
 
 i6. Has the barometer in any way indicated the change 
 noted in the weather ? 
 
 17. What was the mean height of the barometer on the 
 clear days ? 
 
 i8. What was its mean height on the rainy or stormy 
 days ? 
 
 19. In what month has the barometer shown the great- 
 est range of movement ? In which the least ? 
 
 20. In what month has there been the greatest fluctua- 
 tion in the weather ? In what month the least ? 
 
 21. Is there any uniformity in the temperature which 
 accompanies a falling barometer ? Is it the same or dif- 
 ferent with a rising barometer ? 
 
 STUDY OF SIGNAL SERVICE MAPS. 
 
 22. Do the isotherms vary more or less this month 
 from their general direction than they did last month ? 
 
 23. Where is the variation greatest ? What cause can 
 you assign ? 
 
 24. In what part of the country has there been the 
 heaviest rainfall ? 
 
 25. Where has there been the most snow ? 
 
 26. Where is the'region of lowest temperature ? 
 
 27. Have the mountains the same effect upon the 
 isotherms that they had in September ? 
 
 28. Do the coast lines exert the same influence upon 
 the isotherms as last month ? 
 
 29. What was the lowest isotherm that passed through 
 this locality during the month ? 
 
 30. What was the lowest latitude of that isotherm in 
 September? In October? 
 
 31. What inference may be derived from its varying 
 position ? 
 
astronomy. 
 
 The facts that have been noted from time to time as to 
 the variation in the length of day and night, the change 
 of season, the changing shadow, the different position of 
 the rising and setting sun on the horizon, should all be 
 used in giving the pupils a clearer idea of the earth and 
 the sun in their relative positions, and also broader con- 
 ceptions of these bodies themselves. To accomplish the 
 latter end, the pupils should be trained to think of the 
 earth and the sun without the use of the globe for illus- 
 tration. Make the same use of the symbol in this case as 
 in all others ; use it only as an aid to the conception of 
 the object, but ^o not let it entirely take the place of the 
 object, inasmuch as then the pupil's conception must be 
 of the symbol only. 
 
 1. Compare the length of day and night with that 
 of preceding months. 
 
 2. Is the rate of variation each day the same during 
 the month ? How does it differ from that of October 
 and September ? 
 
 3. In what direction is the noon-mark changing ? 
 Why? 
 
 4. Is it changing more or less rapidly than it did in the 
 preceding months? 
 
 5. Are the facts observed thus far sufficient to prove 
 the revolution of the earth around the sun ? 
 
 6. What other supposition can you make that would 
 account for the phenomena observed ? 
 
November] ASTRONOMY. 123 
 
 7. Use a globe, if necessary, to illustrate your meaning. 
 
 8. Has the diminishing day had anything to do with 
 the changing season ? 
 
 9. Show to what other cause the change in season is 
 due. 
 
 10. What time elapses between two new moons ? 
 
 11. Show what the position of the moon must be with 
 respect to the earth and sun when it is new. Why is it 
 crescent shaped ? 
 
 12. In what direction do the horns point? Why do 
 they point in this direction ? Does the direction vary ? 
 Why? 
 
 13. Does the moon always follow the same path across 
 the sky ? 
 
 14. Where does the new mpon always appear first ? 
 Why? 
 
 15. Where is it when between old and new ? 
 
 16. The constellations to be observed are the same as 
 those for October. 
 
 Books for Reference. Astronomy Science Primer, by Lockyer. 
 Newcomb's Astronomy, Briefer Course. See previous months. 
 
(Beograpb^. 
 
 CLIMATE OF NORTH AMERICA. 
 
 By a judicious reference to the Signal Service Maps, 
 and to maps of the continent, upon which are marked 
 the isotherms, a detailed study of the climate of North 
 America may proceed from month to month. It must 
 not be expected that the pupils will generalize sufficiently 
 to be able to see all the laws underlying the distribution 
 of heat and moisture ; yet such use of the maps will 
 assist them to collect in a practical way a large number 
 of the facts upon which the laws are based, and which 
 open the way for a clear understanding of the laws 
 further along. The data gathered from the study of 
 physical maps should be used to supplement and extend 
 the knowledge and experience they have gained from 
 their own observations recorded in the Meteorological 
 Record. 
 
 1. What regions of the United States show the greatest 
 contrasts as to rainfall during the month ? 
 
 2. Note the latitude of the two" regions ; also the ele- 
 vation, the winds which traverse them, and their nearness 
 to the sea. 
 
 3. Can you tell what conditions have most affected the 
 rainfall ? 
 
 4. Which condition has the most to do with the tem- 
 perature of the two regions ? 
 
 J«4 
 
November] GEOGRAPHY. 125 
 
 5. What difference is noted in the temperature of the 
 two places ? 
 
 6. Contrast the character of the prevailing winds upon 
 the Pacific slope with those upon the Atlantic. How do 
 the two regions differ in temperature in the same lati- 
 tude ? 
 
 7. Is the difference in temperature dependent upon the 
 winds ? Note the direction from which they come in 
 each case. 
 
 8. Compare the rainfall of the interior between the two 
 great mountain systems with that on the coasts. What is 
 the direction of the prevailing wind in the interior ? 
 
 9. Compare the rainfall in the northern and southern 
 regions of the interior. Upon what does the difference 
 depend ? 
 
 . 10. How can you account for the difference in tem- 
 perature of the northern and southern divisions of the 
 interior ? 
 
 11. What contrasts in temperature and rainfall are 
 noted between the mountainous parts and the lowlands ? 
 
 12. What contrasts, that you know of, between the peo- 
 ple of different regions are due to difference in climate ? 
 
 13. Are any differences that may exist between the 
 people on the Pacific coast and the Atlantic coast due 
 to difference in climate ? Are the differences as well 
 marked as they are between the North and the South ? 
 Why? 
 
 14. Contrast the people of the far north with those of 
 the extreme south, as to character, habits, occupation, 
 etc. How does the climate affect them ? 
 
 15. How does difference of climate affect the produc- 
 tions in our latitude ? 
 
 16. Where are there the greatest contrasts in the pro- 
 
126 NATURE STUDY. [November 
 
 ductions in the same latitude ? Are these due to climatic 
 differences ? 
 
 17. Compare the rainfall for the month of the region 
 just east of the Rocky Mountains with the region just 
 west of the Appalachian Mountains ; how do you account 
 for the difference ? 
 
 18. Where do the winds that sweep the two regions 
 come from ? 
 
 DRAINAGE OF SOUTH AMERICA. 
 
 1. Note, by the examination of a good map of South 
 America, the ocean which receives the greatest part of 
 the drainage waters ; compare in this respect with North 
 America. 
 
 2. From the flow of the rivers, how can you tell the 
 location of the continental slopes ? Bound the slopes. 
 
 3. Where is the great continental water-parting ? 
 
 4. How does it compare in relative position with the 
 great continental water-parting of North America ? How 
 does it compare in direction ? 
 
 5. What resemblance in the two continents as to their 
 great slopes ? Compare the two -Pacific slopes. The 
 Atlantic slopes. 
 
 6. Do the rivers in the north of each continent indicate 
 any similarity in the slopes in these regions ? 
 
 7. What minor water-partings are indicated by the 
 rivers of the eastern slopes ? 
 
 8. How does the position of the minor water-partings 
 differ from those of North America? How do they 
 compare in direction ? 
 
 9. Compare the slopes of the interior with those of 
 North America. 
 
 IP, In what directions does the interior slope ? 
 
November] GEOGRAPHY. 12? 
 
 1 1. What resemblance and difference can be discovered 
 in the great river systems of the two continents ? 
 
 12. What differences as to their minor river systems ? 
 
 13. What part of the continent must receive the great- 
 est rainfall ? 
 
 14. Compare the northern and the southern parts as to 
 rainfall, basing the comparison upon the size of the 
 rivers. 
 
 15. Compare the regions as to rainfall with correspond- 
 ing parts of North America ; what difference noted ? 
 Why? 
 
 16. What inference, based upon the great rivers, can 
 you make respecting the fertility of different regions of 
 the eastern slope ? What inference in this respect about 
 the western slope ? 
 
 17. Where is .the greatest river basin ? What are its 
 boundaries ? The second, and third in size ? 
 
 18. How does the general slope of these basins as 
 wholes differ ? ' 
 
 19. Compare the Brazilian Highland with the Appa- 
 lachian. 
 
 20. In what latitude are the greatest rivers ? In what 
 latitude are the smallest rivers ? Compare with North 
 America. 
 
(Bcolog^. 
 
 PEBBLES. 
 
 Have each pupil take the entire collection of pebbles 
 gathered during the preceding mouths and assort them 
 with respect to their different characteristics, such as 
 shape, color, material, etc., and by a careful considera- 
 tion learn something of their history. This work should 
 be preceded by as much actual field work as possible. No 
 teacher ought to hesitate to begin such field work, simply 
 because of a lack of experience. It is the want of actual 
 contact with things that renders so much teaching un- 
 satisfactory to the teacher and obscure to the pupils. 
 Visit some stream and spend a few hours studying the 
 pebbles that line its banks. No matter how insignificant 
 the'brook may be, it will hardly fail to afford abundant 
 illustration of the force of water in pebble-making. For- 
 tunate indeed is the teacher who can also visit, with his 
 classes, the shore of a lake or the sea, and there study 
 the same force at work under different conditions. - The 
 wind here plays a part equally important with the water, 
 and the two together, through the ceaseless rolling waves, 
 are as destructive as the swiftest current. The mobile 
 water curling in graceful breakers and spreading itself 
 out in thin layers on the beach, seems to possess but 
 little of the force necessary to accomplish the results 
 wrought out along every shore. But a cupful of water 
 
November] GEOLOGY. 129 
 
 taken from one of these waves will show that it carries a 
 multitude of sand grains that rasp each other and the 
 shore continually. In the larger waves, great quantities 
 of pebbles are constantly rolled in and out with the ad- 
 vancing and retreating waters, and the grinding, grating 
 sound accompanying the alternate movements tell some- 
 thing of the great work that is going on. In times of 
 tempest, the force is increased a thousand fold. With a 
 thundering roar, the water, laden with great bowlders, 
 hurls itself in some places against the shore with a force 
 suflScient to demolish the most substantial works of man ; 
 elsewhere, it rolls up immense heaps of sand, gravel, and 
 stones, and leaves them perhaps hundreds of miles from 
 the starting-point of their journey. If in addition to these 
 illustrations it is possible to study and compare with them 
 the action of the glaciers, the interest will be greatly 
 increased. 
 
 The different forms of the glacial pebbles, the different 
 manner in which they are deposited, the means by which 
 they were carried, will all furnish rich material for care- 
 ful thought and study. It is an excellent exercise for 
 the reasoning powers to trace the history of a pebble 
 from its present condition and surroundings, back 
 through its various stages to its origin in some distant 
 cliff in a remote age. How much of this history can be 
 written, will depend upon the age and experience of the 
 pupils ; some will perhaps read its history only to water 
 which rolled it and made it round ; others will follow it 
 to a particular lake or stream, and still others may see 
 its footsteps leading to some cliff. It little matters how 
 far they go, or how far short of the end they may have 
 to stop, if in accounting for them they learn to properly 
 use and interpret the conditions under which the pebbles 
 
13° NATURE STUDY. [November 
 
 are found. It is not enough for a full conception that 
 they follow merely the footsteps of the pebbles through 
 space ; the element of time is one of greatest importance, 
 but it is a factor that can never be anything but vague 
 in the minds of the most highly trained, and too much 
 must not therefore be expected of young pupils. No 
 effort should be spared, however, to broaden their ideas 
 in this direction, inasmuch as a lack of this conception 
 stands in the way of many people who cannot receive 
 the modern theory of the earth's development. 
 
 Whether all or but one of the above illustrations of 
 the results of water action are at the command of the 
 teacher, let it once more be urged that the means at 
 hand be used. It is the universal experience that not 
 only do the facts so learned remain longer in the mind, 
 but that such lessons often prove to be initiative of a 
 line of observation and thought that lasts through 
 life. 
 
 1. Where were the pebbles in your collection found ? 
 
 2. Can you distinguish those that were found on the 
 banks of a stream from those found on the shore of a 
 lake? 
 
 3. What have you observed in the arrangement of 
 pebbles on the river bank or lake shore ? Is it exactly 
 the same in both cases ? 
 
 4. Have you found pebbles in any considerable quan- 
 tity at a distance from water ? Does the water reach 
 the place in times of floods ? 
 
 5. How can you account for this remoteness of pebbles 
 from water? Are they like the rocks found in the quar- 
 ries in the vicinity ? 
 
 6. Can you tell whether they were deposited by run- 
 ning: or still water ? 
 
November] GEOLOGY. t^^ 
 
 7. Can you tell whether the water was shallow or 
 deep ? 
 
 8. Were they deposited on a shore or in the middle of 
 a lake or stream ? 
 
 9. Are there any other evidences of water'action near 
 by? 
 
 10. Can you form any estimate as to the length of time 
 since they were deposited ? 
 
 11. What things on the surface will assist in giving 
 some idea of the time ? 
 
 12. Are there any large trees in the vicinity ? What 
 is the depth of the vegetable mold ? Is the sod well 
 formed ? 
 
 13. Which gives the best evidence of the length of 
 time since the peb^bles were deposited, the trees, the 
 vegetable mold, or the sod ? 
 
 14. What is the nature of the ground with which they 
 are mingled, sandy, clayey, or loamy ? 
 
 15. How does the surface of a pebble differ from that 
 of a freshly broken stone ? 
 
 ^ 16. How does it differ from one that has been exposed 
 to the air for a long time ? 
 
 17. What makes this difference in surface ? 
 
 18. Assort the pebbles with respect to shape ; what is 
 the most common form ? 
 
 19. Why should they be rounded ? Upon what does 
 the shape appear to depend ? 
 
 20. Is it the hardness of the material in the pebbles 
 or its arrangement that does the more tn determine their 
 shape ? 
 
 21. Assort and rearrange the pebbles again with re- 
 spect to the material composing them ; compare as to 
 color, hardness, etc. 
 
132 ISTATURE STUDY. [Novembef 
 
 22. Can you tell how it is that many different kinds 
 are found together? 
 
 23. Does any one kind of material prevail to any great 
 extent more than the others ? 
 
 24. Is any of the rock composing the pebbles to be 
 found in neighboring quarries ? 
 
 25. Can you recall whether or not the ledges that may 
 usually be seen projecting from a cliff or hillside are of 
 the same kind of rock ? 
 
 26. What evidence have you seen that such cliffs are 
 wearing away ? 
 
 27. A great variety of rock may be picked up by a 
 stream traversing many miles of country, but how is this 
 variety possible with a lake ? 
 
 28. How does the force which rounds off the pebbles 
 in a stream differ from that in a lake or on the seashore ? 
 
 29. What part does the water really play in both cases? 
 
 30. Can you think of any conditions which affect the 
 rate at which pebbles will be transported ? Is this course 
 a direct one to the mouth of the stream ? 
 
 31. Under what conditions will they be deposited 
 along the banks ? - - ' 
 
 32. Under what circumstaces will they be dropped in 
 mid-stream ? When will such be moved again ? 
 
 33. Upon what conditions will those along the bank 
 be allowed to remain ? 
 
 34. Is it likely that pebbles left in sand on the build- 
 ing bank of a river will be again disturbed ? 
 
 Books for Reference. See September. Also Humboldt Library, 
 No. 38. Chapter i. 
 
niMneralog^. 
 
 An interesting variation in the study of thi? subject 
 this month will be found in a consideration of common 
 mineral fuel. 
 
 The pupils should supply themselves, as far as possible, 
 with specimens of bituminous, anthracite, cannel, and 
 splint or block coals ; also, with examples of peat and 
 coke. A good specimen of lignite is likewise needed to 
 complete the list. 
 
 Compare the different specimens as to weight. Which 
 is the heaviest ? The lightest ? 
 
 1. The weight of a solid or liquid compared with an 
 equal bulk of water is called its specific gravity. , To 
 find the specific gravity of a solid, weigh it first carefully 
 on an ordinary balance ; then suspend it from one of 
 the scale pans by means of a fine thread, and immerse 
 it entirely in a small vessel of water, and obtain its Weight 
 submerged. The weight in air divided by the loss of 
 weight in water is the specific gravity. 
 
 2. Which specimen has the greatest specific gravity ? 
 which the least ? Do you notice any correspondence 
 between the specific gravity and the hardness ? 
 
 3. What difference in luster do you notice ? Are they 
 sufficiently well marked to ^nable one to distinguish the 
 different. kinds of coal? Some kinds show a play of 
 different colors, and are known as peacock coal. 
 
 4. How do they differ in hardness ? If you have 
 
134 NATURE STUDY. [November 
 
 different varieties of the same kind, i. e., specimens from 
 different mines, can you notice differences in tliem ? 
 
 5. Try witli a lighted match to set fire to the different 
 specimens, selecting sharp edges or corners for the pur- 
 pose. Which one burns , easiest ? Which with most 
 difficulty ? 
 
 6. Note the odor of the burning substance in each 
 case ; how does the peat differ from the rest ? 
 
 7. What difference in the ways of burning in grates and 
 stoves ? 
 
 8. Compare the coke with the different coals. ,It is 
 the carbon left after burning the coal to rid it of other 
 substances in its composition. It is used in smelting 
 iron. (See Mineralogy for December.) 
 
 9. All the coals, and peat included, originate in the 
 same way, but each different kind represents a different 
 stage in formation. It is the result of immense beds of 
 vegetable material becoming deeply covered in succeed- 
 ing ages by the rock and earth nojv found above the coal 
 seams. Peat is coal in its earliest stage of formation, 
 and anthracite is coal in its latest, and completed stage. 
 It has been changed from the bituminous variety, to that 
 of its present character, by means of heat and pressure. 
 
 10. Examine a piece of the " lead " of a pencil ; this 
 substance is called graphite and is pure carbon. It is 
 also known as plumbago. 
 
 11. If possible, get a piece of native graphite ; note 
 its luster and peculiar feel. 
 
 12. What other use has this mineral besides that in 
 the manufacture of leadrpencils ? 
 
 Reference. Read Applied Geology, by S. G. Williams. 
 
Zoology. 
 
 GENERAL OBSERVATIONS. 
 
 1. Can any of the summer birds be found ? If so, 
 where do they stay ? 
 
 2. Have you found any newcomers ? Have they 
 come from the north or south ? What is their food ? 
 Do they sing ? Are they building nests ? 
 
 3. Is there any insect life abroad ? Watch sharply on 
 warm days and in sheltered places. 
 
 4. Hunt for earthworms. How deep do they burrow 
 in winter ? 
 
 5. In what condition do the fish spend the winter? 
 The craw-fish ? Frogs ? 
 
 6. Look for these under leaves and in mud along the 
 sides and in the bottom of ponds. 
 
 7. Do tadpoles live over winter ? 
 
 ANIMAL MOVEMENTS. 
 
 The following studies should be based upon what the 
 pupils have been able to observe about their own move- 
 ments, as well as those of the common domesticated ani- 
 mals. Ample opportunity should be given beforehand 
 for the observations to be made, and the discussion 
 should not be carried beyond the limits set by those ob- 
 servations. By this, it is not intended to circumscribe 
 too closely any legitimate reasoning that the pupils may 
 
 135 
 
13^ NATURE STUDY. [December 
 
 attempt, but merely to guard against the really vicious 
 habit that some pupils have, in the beginning, of setting 
 up some theory independent of any actual observation, 
 and trying to defend it by vague speculations. That 
 rapid progress may be made, pupils should be encouraged 
 to be candid and to be ready to give up promptly any 
 theory or supposition as soon as it can"be shown to be 
 inconsistent with the facts of observation. > 
 
 1. Why is it necessary for most animals to move from 
 place to place ? Such animals are said to have the power 
 of locomotion. 
 
 2. Do you know of any animals that cannot move 
 about? How do they get their food? How are they 
 protected from their enemies ? 
 
 If possible, secure specimens of coral, sponges, and 
 oysters in the shell. The points of attachment may easily 
 be discoverpd and something of their modes of life may 
 be learned. 
 
 3. How does the power of flight' affect the life and 
 habits of birds ? Consider the advantages in food- 
 getting, and in means of escape and attack, that are due 
 to flight. 
 
 4. How has it affected their distribution ? What bar- 
 riers are difficult for birds to overcome ? 
 
 5. Make a study of the way different animals walk ; 
 first examine those that walk on four legs, as the cat,, 
 dog, horse, cow, rabbit, squirrel, and any others that can 
 be seen. 
 
 6. Contrast the cat and dog ; what is the order in 
 which they place their feet in taking a step ? 
 
 7. Note the motions of the trunk of each as they step ; 
 what difference do you notice ? 
 
 8. What gives the cat its stealthy tread ? Its velvety 
 
ecember] ZOOLOGY. 137 
 
 p^ws contribute partly to it, but they are not the only 
 cause. Notice as the cat steps how the body sinks 
 slightly at the joints where the fore-limbs are hinged to 
 the body at the elbow, and that the same is noticeable in 
 the hind limbs at the heel joint, though somewhat less in 
 amount. These movements, due to the great flexibility 
 of the joints in the foot, and to the fact that when the 
 fore-paw is put to the ground the leg is not vertically 
 under the body but obliquely forward, give a spring to 
 the step that is wanting in all other classes of quadrupeds. 
 
 9. Compare the movements of the cat with those of 
 the dog ; what reason can you think of for the difi'erence 
 in their gait ? 
 
 10. What habit or need pf these animals has done most 
 to fix their gait ? 
 
 11. Compare the movement of the horse and the cow ; 
 in what order do they place their feet in walking ? 
 
 12. In what order are the horse's feet placed in trot- 
 ting ? What i§ the order in pacing or the rack ? In 
 galloping? 
 
 13. Does a cow trot ? How does the movement of the 
 hind legs differ from that of the horse ? 
 
 14. Can you see wherein lies the greater capacity of 
 the horse for speed ? 
 
 15. How does the locomotion of the rabbit differ from 
 that of the cat and dog? What is the order in which the 
 rabbit moves his legs.? 
 
 16. How do the rabbit and the cat differ in making a 
 spring? 
 
 17. What is there in the life of the rabbit that makes 
 him draw his hind legs under him in a crouching atti- 
 tude? 
 
 18. In which are the hind quarters, compared with the 
 
138 NATURE STUDY. [December 
 
 fore quarters, the more developed, the rabbit or the cat ? 
 Compare both of them with the dog. 
 
 19. How do the movements of the squirrel's legs differ 
 from those of the rabbit's ? 
 
 20. Which of the animals studied does the squirrel 
 resemble most in locomotion ? 
 
 21. Compare the development of its different parts 
 with that of the rabbit, dog, and cat ; which does it most 
 closely resemble ? 
 
 22. In what kinds of places do these animals live in 
 their wild state ? How are their movements fitted for 
 such places ? 
 
 23. In animals that walk on two legs, to what uses are 
 the other pair of limbs devoted ? 
 
 24. How does the movement upon two limbs affect the 
 position of the body ? Why is the position of the bird 
 less upright than that of man ? 
 
 25. What are the advantages of the upright position for 
 man ? 
 
 26. Is there any advantage in turning the toes out in 
 walking ? What joint permits of this turning of the toes 
 outward ? 
 
 27. Which is the easier mode of walking, with the feet 
 parallel, or diverging outward at the toes ? Which is the 
 natural and which the acquired way ? Observe children 
 learning to walk. 
 
 28. What difference in the bearing or carriage of per- 
 sons is caused by the direction given the foot in walking? 
 Take a few steps very slowly, and study the position of 
 the body at each step. 
 
 29. In walking with the feet parallel, compare the 
 transverse space between the tracks with the space when 
 the toes diverge. 
 
'December] ZoSlOGY. 139 
 
 V 
 
 30. Which mode of walking contributes more to erect- 
 ness of attitude ? Why ? Test by walking slowly. It 
 will te noticed that in walking with the feet parallel, 
 there is a slight rolling motion at the hips, and that the 
 body sways somewhat from side to side. The swaying is 
 increased since the feet are usually placed a little wider 
 apart transversely, in order to broaden the base. The 
 body is bent slightly forward when taking steps thus. 
 
 ■ When the toes are turned outward, the distance trans- 
 versely between the feet is less, and the swaying motion 
 at the hips is partially lost. 
 
 The body is more easily held erect in walking with the 
 diverging steps. 
 
 The Indian in his long journeys seemed to prefer 
 carrying his feet parallel, while the white man turns his 
 toes outward, as a rule. If one practices until he earn 
 walk well either way, an alternation of the two methods 
 will be found to be restful when taking long walks. 
 
 31. By what means is the body protected from jars in 
 walking ? Which of the above-described modes of walk- 
 ing gives the more elastic step ? 
 
 32. With the shoe removed, notice how the foot spreads 
 gradually as the weight of the body is thrown forward 
 upon it ; what part of the foot should touch the ground 
 first in order to reduce the jar most ? 
 
 33. Why do tight shoes make the step inelastic ? 
 
 34. Why do high-heeled shoes render it difficult to 
 walk with the natural step ? 
 
 35. What is the chief use of the arms in man ? To 
 what is their difference in function, from that of the fore 
 limbs in most animals, due ? 
 
 36. Compare their movements with the wings of a bird ? 
 the fore legs of the horse, dog, cat, and squirrel. 
 
J4<^ NATURU StUJ:)V. [Dfecember 
 
 37. What general modification in form and attitude of 
 the trunk accompanies the increasing freedom of move- 
 ment in the fore limbs ? 
 
 38. In what movements is the hand superior to- the 
 corresponding part in other animals ? Note the position 
 of the thumb and fingers. 
 
 39. What change in the position and attachment of the 
 arms is associated with their great mobility ? 
 
 40. What substitutes for legs do such animals as worms 
 and snakes have ? 
 
 41. Study the movements of a fish in the aquarium ; 
 what is the chief organ of locomotion ? 
 
 42. What seems to have determined the shape of the 
 body ? 
 
 43. How does it turn itself? How does it rise and 
 sink ? 
 
 44. Does it require any effort on the part of the fish to 
 remain in the usual position ? Observe the position in 
 which a dead fish floats. 
 
 45. By what means is it kept in an upright position ? 
 
 46. Since the flight of a bird through the air and the 
 swimming of a fish in the water are somewhat analogous, 
 why is it that the modes of propulsion in the two cases are 
 so very different ? 
 
 Note. Additional topics will be given under this head in the 
 spring. 
 
 THE SKELETON. 
 
 It is desirable in this study to have some prepared 
 skeleto'ns ready for class use. A human skeleton should 
 be procured if possible, both on account of its size and 
 of the practical interest it possesses for pupils. - Skeletons 
 may be prepared quite easily from any small animal. 
 
December] ZOdlOGY. 14I 
 
 After killing the animal, such as, a frog, mouse, or bird, 
 with chloroform or ether, cut all the meat away that 
 comes off without clanger of breaking a bone or separ- 
 ating a joint, and remove the contents of the body cavi- 
 ties. Then make a caustic potash solution, one ounce to 
 a pint of water, and soak the carcass in this, at short in- 
 tervals, removing the flesh as fast as it softens. To re- 
 move the brain separate the skull from the spinal 
 column, and use a crooked wire. With care in preparing 
 the solution so that it will not be too strong, the flesh may 
 be cleaned off before the ligaments soften enough to, al- 
 low the bones to Separate at the joints, and one may in 
 this way secure an articulated skeleton. If the bones 
 become separated, however, they may be mounted 
 diagrammatically by sewing them to stiff cardboard. 
 
 1. Name several animals that you are sure have bony 
 skeletons. 
 
 2. Name some. that do not have skeletons. 
 
 3. Name some that have the skeletons on the outside 
 of the body. 
 
 4. Of what use is our skeleton to us ? 
 
 5. Of what use are the bones of our limbs ? Of 
 what additional use are the bones of the skull ? 
 
 6. What uses can you discover for the ribs ? Notice 
 carefully the act of breathing. 
 
 7. Note in the prepared skeletons the two parts : the 
 trunk, including head and neck, and the limbs, upper 
 and lower. 
 
 8. Can. you find such divisions in the skeleton of a 
 frog ? In the birtl ? The mouse ? The squirrel ? 
 
 9. Which, on the whole, most closely-resembles our 
 own ? 
 
 10. In what respects are, they all alike ? 
 
142 Nature STUDV. [December 
 
 11. Which is most unlike our own ? Which animal 
 most closely resembles us in action ? 
 
 12. Examine the skull of each. Wherein -do they 
 differ most ? 
 
 13. Which contains relatively the largest cavity ? 
 
 14. Which animal shows the greatest amount of 
 intelligence ? 
 
 15. Which the least ? 
 
 16. Note the bones composing the skull. Look for 
 the notched lines where they are joined. These are 
 called sutures. 
 
 17. Do the bones move one upon the other? 
 
 18. Do they form a complete box ? Are any of the 
 skulls incomplete in this respect ? 
 
 The large opening at the base of the human skull, the 
 foramen magnum, is the passage for the spinal cord ; 
 the smaller openings, front and back, are for the passage 
 of nerves and blood-vessels. 
 
 19. How can you account for the difference in the 
 shape of the heads of these animals ? 
 
 20. What gives this difference of aspect chiefly, the 
 bones of the face, or those of the skull ? 
 
 21. In what respects are the trunks all alike ? Which 
 are most alike ? Between which are the greatest differ- 
 ences ? 
 
 22. Which of the animals are most alike in their 
 resting attitude ? 
 
 23. Which are most alike when in action ? 
 
 24. Can you tell whether, it is the movements that de- 
 termine the general form of an animal, or the shape 
 that determines the general movements ? 
 
 25. Canyon see how the movements of the animals have 
 determined any of the features noticed in the trunk ? 
 
December] ZOOLOGY. 143 
 
 26. Which has done more to give shape to the trunk 
 as a whole, the position of the body while in motion or 
 while at rest ? Are all the animals alike in this respect ? 
 
 27. In which animal is the trunk the most flexible ? 
 
 28. How is the trunk rendered flexible ? In what part 
 ' is it most rigid ? AVhy ? 
 
 29. What are the advantages we derive from the flexi- 
 bility of the trunk ? Between the vertebrae are elastic 
 pads of cartilage. Each pad is fastened to the vertebra 
 above and the one immediately below it. The elasticity 
 of the pads and their attachments permit of flexibility 
 without the gliding of one bone over another, as in most 
 joints, which in this case would endanger the delicate 
 spinal cord within. Tliese pads, with the curves of the 
 spinal column, are usually thought to be largely instru- 
 mental in protecting the brain from jars and shocks inci- 
 dent to walking, jumping, and similar movements. That 
 this is not so to any great extent is evident to every one 
 who has unexpectedly stepped into a hole a few inches 
 deep. When knowingly taking such a step, the leg is so 
 held as to remove the jar by bending slightly at the joints ; 
 otherwise the position does not admit of this bending, 
 and the shock is conveyed to the base of the spinal col- 
 umn and thence to the brain, and, even in a trivial mis- 
 step, it is one that is very generally dreaded. 
 
 30. In which animal are the fore and hind limbs most 
 alike ? In which most different ? 
 
 31. Which animal uses its fore limbs most nearly as 
 we do ? 
 
 32. In which animal is there the greatest difference be- 
 tween the fore and hind limbs ? In which is there the 
 greatest similarity ? 
 
 33. In which animal is there the greatest difference in 
 
144 NATURE STUDY. [December 
 
 the use of the fore and hind limbs ? Note the relative 
 length of the fore and hind limbs. 
 
 34. Count the bones in the fore limb or arm of a man, 
 and compare with the other skeletons. 
 
 35. In which skeleton do the bones admit of the most 
 varied movement ? Which the least ? 
 
 36. What is the chief use of the fore limb that has the 
 greatest range of movement ? 
 
 37. Note the relative length of the bones in the upper 
 and lower arm in each animal. 
 
 t 38. In which animal are they relatively strongest ? 
 Note the relative length in each case. 
 
 39. Can you find bones in the fore limbs of the other 
 animals to correspond with all those in the arm of man? 
 
 40. Which is most like man's arm in use ? 
 
 41. How are the upper limbs fastened to the trunk in 
 each case ? Are they all alike in this respect ? 
 
 42. What cause can you see for the difference, in this 
 particular, between the mouse and bird ? Between man 
 and the mouse ? 
 
 43. In which animal are the hind limbs relatively 
 strongest? How do they compare with the fore limbs as 
 to the number of the bones ? 
 
 44. Note their attachment to the trunk ; how do they 
 differ in this from the fore limbs ? 
 
 45. How have the bodily movements affected the hind 
 limbs in each case ? 
 
 46. How do the movements of the bones in the hind 
 limbs differ from those of the corresponding bones in 
 the fore limbs ? Note the relative length of the bones 
 of the hind limb, and compare with the fore limb. 
 
 47. How has the attitude of the body modified the 
 hind limbs in each case ? 
 
December] ZOOLOGV. 145 
 
 48. How are they adapted to the movements of the 
 animal ? 
 
 49. In which skeleton is the foot most unlike the hand ? 
 In which is the greatest resemblance ? 
 
 50. In which are the movements and uses of the foot 
 and hand most nearly alike ? In which most unlike ? 
 
 51. Locate in four-footed creatures like the horse, 
 dog, cat, etc., these joints found in man ; toe joints, heel 
 joints, knee joint, hip joint, wrist joint, finger joints, el- 
 bow joint, and shoulder joint. 
 
^ Botany. 
 
 A few observations should be kept up this month on 
 the effects of frost and freezing on plants. 
 
 1. Sometime during a hard freeze examine the smaller 
 twigs. Are they frozen through ? How protected ? 
 
 2. Open the buds ; are they frozen ? What are the 
 ways by which the buds are protected ? 
 
 3. Are they wet through when it rains ? 
 
 4. Can you still distinguish the newly formed wood ? 
 
 5. Is any part of the twig still green ? 
 
 6. Look for seeds of weeds and other plants that have 
 been scattered about ; do they freeze ? Can you find 
 any that are sprouting ? 
 
 7. Can you tell whether or not it kills them? 
 
 8. Are- those that are buried in a few inches of earth 
 frozen ? 
 
 9. Look for acorns and other nuts ; how does the 
 freezing affect them ? 
 
 10. Can you find any plants whose stems have been 
 killed, but whose roots are still living ? 
 
 11. Do the roots of the trees freeze ? 
 
 12. Can you find any injurious effects of frost and 
 freezing on the trunks of trees ? 
 
 13. Can you find any growing plants ? 
 
 Z46 
 
pb^sics. 
 
 THE LEVER. 
 
 It is the intention that the lessons given upon the 
 lever should supplement those given in Zoology this 
 month on the movements of animals. The pupils must 
 provide themselves with small sticks about a foot long, 
 and a block of wood, stone, or iron an inch or two in 
 diameter. 
 
 1. Suppose the block were a weight that could not be 
 conveniently lifted by hand, illustrate with the stick the 
 different ways in which a bar might be used in lifting it. 
 
 2. The pupil should work with this problem until he 
 finds the three ways of using the stick as a lever. He 
 should see that in each case there is a fixed point about 
 which the lever moves which is called the fulcrum. Also 
 that in each there is a point where the power is applied 
 and another point where the weight is placed. He 
 should note that the form of the lever depends upon the 
 relative position of these three points, which are usually 
 represented by the letters F, W, P. The distance from 
 F \.o P \% the power arm, and from F to IV the weight 
 arm of the lever. The three kinds are distinguished as 
 first-class, when F is between P and W ; second-class, 
 when W is between i^'and P, and third-class, when P is 
 between F and W. It will be noticed that one need 
 remember only the point which lies between the ends in 
 
 147 
 
14S NATURE STUDY. [December 
 
 order to tell the class of lever, and in the order of first, 
 second, and third, the letters stand F W P, initials which 
 no pupil of Cook County Normal School will find it 
 difficult to remember. 
 
 3. How must the lever of the first class be used to lift 
 the greatest weight ? What do you notice about the 
 relative length of the two arms P F and W Ft 
 
 4. Use it again so that it will be of the least use in 
 lifting a weight ; is there any advantage in such use ? 
 Note again the relative length of the two arms. 
 
 5. In the same way, use the second and third class 
 forms of the lever. Note each time the relative length 
 of the two arms, and also as to whether the advantage 
 gained in each case is one of power in lifting the weight 
 or of distance through which it is moved. 
 
 6. Can the lever be so used that there will be no gain 
 of either power or distance ? 
 
 7. Is it possible to gain power with each form of 
 lever ? 
 
 8. What do you notice about the relative distance 
 through which the power and weight move in the second 
 class lever? Notice the same in the third class. 
 
 9. What determines the distance through which the 
 power or weight shall move ? 
 
 10. What forms of the lever have you seen workmen 
 use ? When do they use the first class ? When the 
 second class ? When the third class ? 
 
 11. Study some of the parts of the animal body as 
 levers. What are their uses ? 
 
 12. In studying the levers of the body, the pupil 
 should first be required to fix the limits or ends of the 
 lever, then the fixed point or fulcrum, then the weight 
 ^nd power, If this order be followed carefully, one step 
 
December] PHYSICS. 149 
 
 at a time,'it is not difficult to fix thie levers of the body 
 and to tell the different orders. 
 
 13. In the manner sugg.ested, locate and describe the 
 levers concerned in the following movements : (i) Flex- 
 ing the forearm ; (2) extending forearm ; (3) lifting the 
 entire arm . outward and upward from the body ; (4) 
 opening the mouth ; (5) closing the mouth ; (6) neck 
 rigid, tipping head backward and forward ; (7) throw- 
 ing the head from one shoulder to the other ; (8) 
 straightening up when the body' is bent at the hips ; 
 (9) lifting the body to tip-toe position ; (10) standing on 
 the heels and lifting the toes; (11) hold the foot clear 
 of the floor and tap it with the toes ; (12) in same posi- 
 tion lift the toes ;. (13) flexing the lower part of the leg ; 
 (14) in swinging the leg at the hip joint ; (15) in the rib 
 movement in breathing. 
 
 14. What class is most commonly found in the animal 
 movements ? 
 
 15. What advantages are derived in most cases froni 
 the form employee! ? 
 
 16. What disadvantages in the lever of the forearm ? 
 
 17. In what position can you get the most strength or 
 lifting power in the forearm ? Test this by straightening 
 the arm out on a table and then slowly flexing it against 
 the upper arm. 
 
 18. Can you find similar levers used in the movements 
 of other animals ? 
 
 fg. Why is it so difficult to hold an animal by its 
 hind legs ? Note the leverage and the class of lever in 
 the four-footed animals in the leg below the heel. 
 
 20. What kind of a lever is there in the wing of a bird ? 
 
 21. How do animals move that ^re not provided with 
 bones for levers ? 
 
15° NATURE STUDY. [December 
 
 22. The pupil should be asked to trace out the levers 
 that may be found in the wheel work of different ma- 
 chines. 
 
 EQUILIBRIUM OF BODIES. 
 
 In this subject many interesting experiments may be de- 
 vised and many illustrations may be drawn from the 
 experience of the pupil which will acquaint him some- 
 what with the force of gravitation and its action upon 
 bodies of different size, shape, and mass. 
 
 1. When a ruler or any body is held at rest in the hand 
 is there any evidence. that there is a force acting upon 
 it ? How is that force measured ? What is the meas- 
 urement of it called ? 
 
 2. When the hand is removed, what happens to the 
 object ? What kind of a line does it follow in its move- 
 ment ? What is this particular line called ? 
 
 3. Can you balance every body upon a point of sup- 
 port that is smaller than the base of the object ? Can 
 you balance any of the bodies in more 'than one posi- 
 tion ? Try such bodies as blocks of wood, balls, sticks, 
 etc. 
 
 4. The point in a body upon which the body will bal- 
 ance in any position is called the center of gravity. 
 Where is such a point in a ball of wood or iron ? 
 Where is it in a cube of wood ? 
 
 5. In order to find the center of gravity in any body, 
 suspend it from some point and note the direction of 
 the vertical line from the point of suspension through or 
 across the body ; now suspend it from another point and 
 note when the vertical line from the second point of sus- 
 pension intersects the first. The point of intersection is 
 the center of gravity. Does the center of gravity lie 
 within the body or on its surface ? 
 
December] PHYSICS. 151 
 
 6. Is it always within the body ? Where is it in a ring 
 or hoop ? In a holl.ow sphere ? 
 
 7. The vertical line from the center of gravity is 
 caWtd ihe. line of direction. In considering the stability 
 of bodies it is of the highest importance to keep the 
 
 , center of gravity and the line of direction constantly before 
 the mind. 
 
 8. When a cube rests on a table on one side, can you 
 see where the line of direction must be? 
 
 9. When you roll the cube from one side so that it will 
 rest upon another, what kind of a line does the center of 
 gravity describe ? 
 
 10. Compare the rolling of a ball with the turning of 
 the cube ; which is easier? How does the line described 
 by the center of gravity in the ball differ from that de- 
 scribed by the cube ? 
 
 1 1 Place a cone on its apex and try to balance it ; as 
 it falls over, what kind of a line is described by the cen- 
 ter of gravity ? 
 
 12. A body is said to have stable equilibrium when 
 • any movement which disturbs its equilibrium raises the 
 
 center of gravity j when any such movement lowers the 
 center of gravity it is in unstable equilibrium. When 
 the center of gravity moves in a line parallel with the 
 floorer other support the body is in indifferent or neutral 
 equilibrium. Test various bodies that you have handled, 
 such as the cube, cone, pyramid, ball, prism, etc. These 
 may be modeled in clay. 
 
 13. Can you place a cone in stable equilibrium ? In 
 unstable equilibrium? In indifferent equilibrium ? 
 
 14." In tipping anybody over notice the path of the 
 line of direction at the point where the body refuses to 
 come back to its original position. Under what condi- 
 
152 Nature STOBV. [Decembef 
 
 tions will the body always resume its first position when 
 its equilibrium is disturbed ? 
 
 15. Under what conditions do you find a body most 
 stable ? Least stable ? 
 
 16. Where is the center of gravity of your own body ? 
 
 17. Why is it more difficult to push one over forward 
 than backward ? Why may one be easily pushed over 
 sidewise ? 
 
 18. Why is a wagon with a high load of hay more 
 easily upset than one with the same weight, but less 
 bulk ? 
 
 19. Can you understand why tight rope walkers 
 always carry a heavy balancing pole ? Why does a 
 porter with a pack on his back lean forward, while if 
 the same weight were in a pail and carried in his hand 
 he would walk upright ? 
 
 20. Why is it difficult to walk on stilts at first ? Why 
 is it impossible to stand steadily upon them ? 
 
 21. Why does a ball roll down hill? Why does a bi- 
 cycle rider fall over sidewise when he stops ? A some- 
 what more difficult thing to explain is why he and his 
 wheel can remain upright while in motion ; can you see 
 the reason ? , 
 
 22. Thrust a pin half-way to the head in a medium 
 sized cork. Stick two penknives into th* cork one op- 
 posite the other and so that the handles will slant down- 
 ward below the end of the pin. Why will the cork 
 remain upright balanced upon the pinhead ? 
 
 HEAT. 
 
 A study of the following topics in this subject should 
 be applied in the explanation of whatever natural phe- 
 nomena the pupils may have observed, which rests upon 
 
December] PHYSICS. IS3 
 
 the principles here illustrated as a cause. Among the 
 points which may "be mentioned, are the cooling of sur- 
 faces upon which dew is formed, the origin and direction 
 of air currents, modes of ventilation, effects of different 
 kinds and colors of clothing upon the heat- of the body, 
 and so on. Careful consideration of the differences in 
 bodies as to their capacity for heat will assist to a clearer 
 comprehension of the relation of land and water masses 
 to climate. 
 
 Liquefaction. 
 
 1. Take two wide-mouthed bottles as nearly alike as 
 possible and fill one with ice and the other with the same 
 weight of water ; place both in a pan of boiling water 
 ovet a lamp or gas jet. 
 
 2. Note the temperature of ea^ch at intervals until the 
 ice is all melted. 
 
 3. Have the two vessels received the same amount of 
 heat ? Note the conditions carefully under which each 
 is placed. 
 
 4. What difference in temperature when the ice is 
 melted ? 
 
 5. Had the temperature of the bottle with the ice 
 in it risen at all at the moment it was melted ? What 
 change did the heat bring about in the bottle ? 
 
 6. After the ice has melted, does the thermometer in- 
 dicate any change ? 
 
 7. Remove to a sand bath and- raise the temperature 
 of the water until it boils. A thin glass beaker or vessel 
 of tin should be used for the purpose. 
 
 8. What is the temperature at which it boils ? Hold 
 the thermometer in the steam over the liquid. 
 
 , 9. Increase the heat by means of more burners ; does 
 the temperature rise ? 
 
IS4 Mature study. [December 
 
 10. What has been accomplished by the heat in these 
 experiments with the water and ice ? 
 
 11. JWhen heat is appHed to a body or fluid does it 
 always show itself as temperature ? When not shown as 
 temperature how is it expressed ? 
 
 Conduction of Heat. 
 
 1. In heating the metaUic rods (i) at one point, what 
 did you notice as to the effect upon the entire rod ? 
 
 2. Did the parts farthest from the flame become heated 
 by radiation ? 
 
 3. What parts became heated first ? What parts last ? 
 
 4. How does the heat get from one end of the rod to 
 the other ? 1 
 
 5. Procure pieces of different kinds of wire or rods, 
 such as copper, iron, and brass, one foot long. Twist 
 them together in pairs for two inches at one end and 
 from the point where they are twisted spread them apart 
 in something of a U shape. At some distance from the 
 twist, and at equal distances from each othfer, fasten by 
 means of shoemaker's wax small bullets or shot to each 
 wire. Support horizontally so that the twisted ends may 
 rest in the flame of the lamp. Protect the balls from the 
 radiant heat from the lamp with a screen. 
 
 6. From which wire do the balls drop first ? What 
 does that indicate ? 
 
 7. Which is the last in losing the balls ? 
 
 8. Bodies which become heated from particle to parti- 
 cle as in the case of the wires are called conductors. 
 
 9. What difference between heating by radiation and 
 conduction ? 
 
 10. Which is the better conductor, iron or copper ? 
 Brass or copper ? Iron or brass ? 
 
December] PHYSICS. ISS 
 
 11. Why does a piece of iron become heated when 
 lield in the hand ? Why does it at first feel cold ? 
 
 12. Why does wood feel less cold than iron to the 
 touch ? Why are iron handles sometimes tipped with 
 wood ? 
 
 13. Is the iron really colder than the wood ? 
 
 14. Why does our bed feel cold at first ? How does it 
 become warmed ? 
 
 15. Why does a blanket seem warmer than a sheet ? 
 
 16. Why is linen clothing worn in summer and woolens 
 in winter ? 
 
 17. Why is it regarded safer for one's health to wear 
 light woolens next the body, even in summer ? 
 
 Convection. 
 
 1. Fill a good-sized test-tube, or, better still, a glass 
 beaker, nearly full of water. Sprinkle into it a little 
 powdered chalk and heat gradually. 
 
 2. Look closely for any cjirrents that may be started 
 as indicated by the particles of chalk. 
 
 3. Make a drawing of the beaker, and mark with ar- 
 rows the direction of the currents. 
 
 4. Where does the water become heated first ? How 
 do the other portions become heated ? 
 
 5. Using light pieces of paper, look for currents 
 of air in the room. Try the space over the stove or 
 register ; also the cracks above the doors and at the 
 bottom. Open the window at top and bottoni half an 
 inch. Use a lighted candle or taper in looking for a 
 draught. 
 
 6. What is the cause of the air movements in the 
 room ? 
 
 7. Can you account for their direction ? Using a 
 
IS6 NATURE STUDY. [December 
 
 thermometer, find out where the lowest temperature is in 
 the room, and whether it is at the top or bottom. 
 
 8. Recall the experiment illustrating expansion of air, 
 which was performed in November. 
 
 9. How are those parts of the room distant from the 
 stove or register heated ? 
 
 10. Compare the heating of the air in the room with 
 the heating of the water in the beaker. 
 
 ir. The manner in which the water in the beaker and 
 the air in the room are heated is known as convection. 
 12.. How does convection differ from conduction ? 
 
 13. Fill a test-tube nearly full of water, and very 
 cautiously heat it near the top in the flame of the lamp ; 
 test at intervals with a thermometer the top and bottom 
 portions. A small piece of ice held at the bottom of the 
 water by a fragment of lead or a pebble will make the 
 contrast stronger. Great care must be exercised in 
 heating the test-tube in the last experiment, or it will 
 crack ; why is this ? 
 
 14. Does the water become heated throughout more 
 or less quickly than before ? 
 
 15. What makes the difference? By what process is 
 it heated in the latter case ? 
 
 16. Why is it not heated by convection ? 
 
 17. Study the mechanism of the kitchen range, and 
 explain how the water in the boiler is heated. 
 
 18. When the fire is starting, which part of the boiler 
 gets warm first ? Place the hands at different points on 
 the outside. 
 
 19. How does the water in the lake become heated ? 
 Explain why it is always cold a little distance below the 
 surface. How does the ocean become heated, by con- 
 duction or convection ? 
 
TDecember] FffYSICS. IS 7 
 
 20. How does the sun warm the earth ? 
 
 21. Is the air warmed directly by the 5un ? 
 
 22. Can you see any reason why it is colder on a 
 mountain peals; than it is on a low plain ? 
 
 23. Hold a piece of plain glass between the hand 
 and the sun ; can you notice any change in the amount 
 of heat that reaches the hand ? 
 
 24. Instead of the plain glass, use a common magnify- 
 ing glass or lens ; hold it so that the sunlight passing 
 through it is reduced to a small point. Allow this to 
 fall upon the hand or upon paper. How can you 
 account for the great heat at that point ? Is it hot out- 
 side the area of this spot ? Try to make a drawing 
 showing by lines the way the heat must come to the lens 
 
 »and the way it must leave it on the opposite side. Heat 
 bent out of a straight course by some substance which it 
 passes through is said to be refracted. Compare reflec- 
 tion with refraction. 
 
 Capacity for Heat. 
 
 1. In two vessels of the same kind, place equal 
 amounts of water ; raise the water in one of the vessels 
 to the boiling point and take the temperature. Find the 
 temperature of the water in the other vessel, and then 
 add the boiling water to it. 
 
 2. What is the. temperature of the mixture ? How 
 much was the cool water warmed ? How much was the 
 warm water cooled ? Is the number of degrees the same 
 in both cases ? Is the result what you would expect 
 from the experiment ? 
 
 3. Take a piece of lead weighingthree or four ounces. 
 If not already in a sheet, pound it out thin and roll 
 loosely. Suspend in a vessel of boiling water, and allow 
 it to remain until it has the same temperature as the 
 
158 NATURE STUDY. [December 
 
 water. Into another vessel put a weight of water equal 
 to that of the lead, and take its temperature. As quickly 
 as possible drop the lead into this vessel of water and 
 take the temperature. How much does the temperature 
 of the water rise ? How much does that of the lead 
 fall ? 
 
 4. In the same way use different substances, as zinc, 
 sheet iron, tin, brass, and copper. 
 
 5. Notice how much the water gains in each case and 
 how much the metal loses. 
 
 6. How much heat must have been in the metal when 
 taken from the boiling water ? What became of this 
 when it was dropped into the cooler water ? 
 
 7. Does the thermometer always tell us when heat is 
 added to a substance ? Recall the experiment of the 
 melting ice in the November work. 
 
 Sources of Heat. 
 
 1. How do we warm our houses ? What are necessary 
 in order that we may have a fire ? 
 
 2. When the wood or coal burns what kind of a change 
 takes place ? (See Chemistry for November.) 
 
 3. Have you ever known heat to be produced without 
 the use of fire ? 
 
 4. Try rubbing a nail with a file. Rub two sticks to- 
 gether. Rub the edge of a penny over the sleeve. 
 What results in each case ? 
 
 5. Pound a nail on a stone or iron block with a ham- 
 mer ; what is the result ? 
 
 6. What is the real difference between the two ways 
 of getting heat, that of burning the wood, and that of 
 making it warm by rubbing it ? 
 
Cbemistri?. 
 
 PREPARATION OF OXYGEN. 
 Materials Needed. 
 
 1. Test tubes, one for each pupil if possible, about six 
 inches long and three-quaiters of an inch in diameter. 
 
 2. A six-ounce Florence flask. 
 
 3. Corks to fit the above. 
 
 4. Glass tubing having a bore of about three-sixteenths 
 of an inch. A piece about eight inches long for each 
 pupil. Bend the tubes at a right angle two inches from 
 one end, and put the short end through a hole in the cork. 
 
 5. Glass bottles with wide mouths, at least one for each 
 pupil, and a few empty glass fruit jars. Morphia bottles 
 are very useful. 
 
 6. A pneumatic trough. Any vessel holding five or six 
 inches of water will answer. A small bench with a hole 
 in the center must be used for supporting inverted vessels 
 in the water with their mouths below the surface. To 
 make this take a strip of tin about eight inches long, four 
 inches wide, and bend up two inches at each end. This 
 will be strong enough to .support small jars and bottles. 
 
 7. Alcohol lamps or bunsen burners. 
 
 8. About an ounce of potassium chlorate and an 
 equal amount of black oxide of manganese for each pupil. 
 Test these materials by powdering a little of the potas- 
 sium chlorate and mixing with the same amount of the 
 
l6o NATURE STUDY. [Decembef 
 
 black oxide and heating in an open tube ; if the mixture 
 melts quietly they are safe ; if slight explosions occur, 
 throw the materials away, as they are not pure and are 
 dangerous. 
 
 Experiments, 
 r. Mix the powdered crystals of the chlorate with an 
 equal amount of the black oxide ; put about one inch 
 depth of this into a test tube and fix with a cork having a 
 tube through it as described above. Fill one or more 
 small bottles with water and invert in the pneumatic 
 trough, which should have four or five inches of water in 
 it. Place one of these upon the bench with the mouth 
 over the hole. Support the test tube over the flame so 
 that the end of the glass tube will be under the surface 
 -of the water in trough, but not under the bottle on the 
 tench. After the bubbles have escaped for a few mo- 
 ments, arrange the end of the tube under the hole in the 
 bench so that they will rise into the bottle. 
 
 2. Why not put the end of the tube under the bottles 
 at once ?' 
 
 3. Why fill the bottle first with water? 
 
 4. Can you see anything passing out through the 
 tube ? 
 
 5. What change do you notice in the materials in the 
 test tube ? 
 
 6. What is the nature of the substance rising into the 
 bottle of w'ater ? 
 
 7. When the water has left the bottle, remove it from 
 the hole, but keep the mouth below the surface. If gas 
 still comes off, collect if in another bottle. 
 
 8. Slip a piece of glass as a cover under the bottle 
 filled with gas, and holding it tightly in place, remove 
 the bottle and turn it quickly right side up. 
 
December] . CHEMISTRY. l6l 
 
 9. Provide a number of fine splinters. Light one of 
 tliem, and, when fairly blazing, blow it out and quickly- 
 thrust the glowing end into a jar or bottle that contains 
 air ; note carefully all that happens. 
 
 10. Light again, and in the same manner thrust it into 
 the jar filled with gas from the test tube ; what difference 
 do you notice? 
 
 11. What evidence that there is something in the jar 
 different from air ? 
 
 12. With a fresh supply of gas, repeat the experiment 
 suggested above in (g), using a short piece of a candle. 
 Fasten a light piece of wire around the candle by which 
 it may be lowered into the jar. 
 
 13. After the pupils have made oxygen for themselves, 
 it may be desirable to have a larger quantity and have it 
 collected in the fruit jars. To do this take about an 
 ounce of the potassium chlorate and mix with the man- 
 ganese as before, and use the Florence, flask. Heat 
 gradually, and when enough has been collected remove 
 the end of the tube from the water before removing the 
 flame. If this precaution is not observed, the water will 
 run back into the flask and break it. 
 
 14. Put a small amount of sulphur in a thimble and 
 ignite it ; by means of a wire wrapped around it for a 
 handle, lower it into a jar of the gas. 
 
 15. Ignite a piece of well-charred charcoal and lower 
 into a fresh jar of gas. 
 
 16. Fasten a small splinter to an iron wire, and after 
 lighting lower it into a jar of the gas. 
 
 17. Get a worn-out watch spring from a jeweler and 
 draw the temper by heating; and then straighten it ; 
 fasten to a stick as in (16) and, after igniting, lower it into 
 a jar of the gas. 
 
1 62 NATURE STUDY. [December 
 
 i8. In the same way try a narrow ribbon of zinc. 
 
 19. In the foregoing experiments, does the gas in, the 
 jars burn ? 
 
 20. In what respects is it like air ? 
 
 21. What happens after burning a substance, as wood, 
 in the jar for some time ? Compare this result with what 
 was observed when burning a taper in a bottle of air. 
 
 22. The gas collected in the jars used in these experi- 
 ments is called Oxygen. It is the element in the air which 
 enables us to have fires in our stoves and grates. 
 
 23. It is also the life-giving element of the air for ani- 
 mals. How does it enter our bodies ? 
 
 24. Why should chimneys have a good draught to 
 make good fires ? 
 
 25. Why do we fan or blow a fire to start it ? 
 
 26. Why do we need ventilation in a room ? 
 
 27. In what respects does oxygen differ from the car- 
 bon dioxide gas ? (See Chemistry for November.) 
 
 28. Write a list of the experiments perfprmed and state 
 the results obtained. 
 
1. Has the prevailing wind changed direction within 
 the last three months ? What may be given as causes ? 
 
 2. Has the cloudiness increased or diminished ? 
 
 3. How does the character of the rains differ ffom 
 those in September ? What causes the difference ? 
 
 4. From what direction do the heaviest rains come ? 
 
 5. In what month has the greatest number of fogs 
 been noted ? 
 
 6. What conditions are most favorable for the produc- 
 tion of fogs ? 
 
 7. Is the wind more or less variable than it has been in 
 the preceding months ? 
 
 8. What wind precedes the heaviest rains ? 
 
 9. What wind accompanies clearing weather ? 
 
 10. Is the temperature increasing or diminishing this 
 month ? What cause can be given ? (See Astronomy 
 for December.) 
 
 11. Is the rate of change in temperature more or less 
 rapid than it was in the preceding three months ? 
 
 12. When have most of the rains occurred, in the day- 
 time or during the night ? 
 
 13. Of those rains which occurred in the daytime, did 
 the greatep number fall in the forenoon or afternoon ? 
 
 14. Have the frosty mornings been followed by fair 
 or foul weather? 
 
 15. On what date did the first snow fall ? 
 
 16. From what direction do the snows come? 
 
 163 
 
l64 NATURE STUDY. [December 
 
 17. Do all the rains come from the same direction ? 
 
 18. Examine some single snowflakes closely ; are they 
 all alike ?. 
 
 19. Are they all of regular form? Why are some 
 flakes larger than others ? 
 
 20. How do snow clouds differ in appearance from- rain 
 clouds? 
 
 21. How does the history of a snowfiake resemble 
 that of a raindrop ? In what respect is it different ? 
 
 22. Does the barometer in any way herald the approach 
 of a snowstorm ? 
 
 23. At what temperature did the heaviest snow fall? 
 Did the temperature rise or fall after the snowing 
 ceased ? 
 
 STUDIES OF SIGNAL SERVICE MAPS. 
 
 24. Draw a line across the map connecting the points 
 farthest south where snow has fallen during the last 
 month. This may be called the snow line' for the 
 month. 
 
 25. Where does the snow line extend farthest south? 
 
 26. Where is its most northern point? 
 
 27. How many degrees of latitude are they apart? 
 How many miles are they apart north and south ? 
 
 28. How do the coast lines affect the snow line ? 
 
 29. On which coast is it farthest north ? Why is 
 it so ? 
 
 30. Which mountains have the most marked effect 
 upon it, the Rocky Mountains or Appalachiarj system ? 
 
 31. How does the course of the storms for this month 
 compare with that for the preceding months ? 
 
 32. Have the courses of the great rivers affected, ap- 
 parently, the direction of the storms? 
 
December] METEOROLOGY. 165 
 
 33. Have the mountains determined the course of the 
 storms ? 
 
 34. Have there been any great storms with rain in one 
 part-of.its area and snow in another part? 
 
 35. Contrast the Pacific slope with the Atlantic as to 
 rainfall and temperature this month. 
 
astronomy. 
 
 1. Compare the relative length of day and night in 
 December with that of preceding months. 
 
 2. What has been the average rate of change in the 
 length of day during the month ? Compare with the 
 former months. 
 
 3. Note the position of the noon shadow about, the 21st 
 of the month. Has it changed its position more or less 
 rapidly this month than it did in September ? 
 
 4. Stretch a string from the top of the upright piece 
 at the end to the point touched by the noon shadow in 
 September when the day and night were equal, and another 
 string to the point touched by the shadow in December 
 when the day is shortest. Note the size of the angle be- 
 tween the two lines. If possible, measure it. If these 
 two lines were continued into space, what two points in 
 the celestial sphere would be found ? 
 
 5. Note as directed in September the points on the 
 horizon where the sun rises and sets. Why is it that when 
 the shortest day is reached in this month the shadow does 
 not at once begin a retrograde movement on the shadow 
 stick. The time of the shortest day of the year is called 
 the winter solstice. This means the sun stands still. Can 
 you see a reason for the use of the word solstice ? 
 
 6. How have these positions changed since Septem- 
 ber ? 
 
 7. What suppositions can you make regarding the earth 
 and sun which will account for the changes ? 
 
December] ASTRONOMY. 167 
 
 8. Supposcyou were to draw lines across the sky mark- 
 ing the apparent path of the sun every day since Septem- 
 ber, what would be the relation of these lines to each 
 other ? 
 
 9. How much of the quarter circle on the horizon has 
 the sun traversed since the day and night were equal ? 
 
 ro. Compare the number of degrees estimated in (9) 
 with the size of the angle measured in (4). 
 
 11. Can you show, by means of the globe, on the sup- 
 position of revolution, what part of the earth's orbit has 
 been traversed since the autumnal equinox ? 
 
 12. How many days have elapsed since then ? 
 
 13. Does the fraction of a year which has passed since 
 the equinox correspond to the part of the orbit over 
 which the earth has passed since then ? 
 
 14. What supposition can you make that will explain 
 the lack of correspondence ? 
 
 15. Explain, by means of a globe, if necessary, why the 
 sun has seemed to change its position since September. 
 
 16. Write a brief description of the condition of animal 
 and plant life. Compare with September. To what 
 cause or causes are the differences due ? 
 
 17. Do you always see the same side of the moon ? 
 By means of a globe, sun, and moon, explain. 
 
 18. Can you see any reason for believing that the moon 
 revolves round the earth ? 
 
 19. If the moon revolves round the earth as the earth 
 moves through its orbit round the sun, can you tell what 
 kind of a line the moon must describe ? 
 
 20. Have any of the constellations which were seen last 
 month disappeared ? 
 
 In addition to those of last month that are still visible 
 are Auriga, Orion, and Gemini. 
 
(Beoarapb^. 
 
 NORTH AMERICA. 
 Soil and Productions. 
 
 1. What things can you name that affect the fertility 
 and productiveness of soils ? 
 
 2. Make use of a good physical relief map and study 
 the conditions which affect the productiveness of the 
 different regions. From what you know of plant life, 
 what are the primary conditions necessary for it. 
 
 3. Contrast the growth and general appearance of a, 
 plant during a wet season with its condition during a dry 
 one ? 
 
 4. What is the effect of heat and moisture upon the 
 plants that you have noticed ? 
 
 5. Use a map which shows the character of the vege- 
 tation in different regions ; what climate have those parts 
 where vegetation is most luxuriant ? 
 
 6. What contrasts in the products of the Atlantic and 
 the Pacific coast regions ? 
 
 7. Compare the northern half with the soutTiern on 
 each coast ; on which coast is the contrast greater ? 
 
 8. In the great central plain, contrast the eastern and , 
 the western halves ; in which half within the United 
 States are the productions more uniform ? 
 
 9. In which half do the agricultural productions extend 
 farther north ? 
 
Decemter] GEOGRAPHY. 169 
 
 10. Where are the great wheat-growing regions ? How 
 can you account for the wheat-growing region of 
 Texas, since a similar one is not to be found in Mis- 
 sissippi ? 
 
 11. Where is the rice production greatest? Contrast 
 the conditions that it requires with those necessary for 
 wheat. 
 
 12. Note the cotton-growing region; does the belt 
 reach the Rocky Mountains ? Can you see a reason for 
 this ? 
 
 13. Contrast the corn-producing regions with those 
 mostly devoted to wheat. 
 
 14. What is the relation of the tobacco and hemp re- 
 gions to those of cotton and corn ? 
 
 15. What grains flourish in a cooler climate than that 
 best adapted for wheat ? 
 
 ' 16. Make a study of the different fruit regions ; what 
 part of the continent includes the greater part of the 
 fruit-growing regions .'' 
 
 17. Compare and contrast the Atlantic and the Pacific 
 coasts. What are the staples of each ? 
 
 18. Where is the southern boundary of the apple region? 
 Where is the chief apple-growing district ? 
 
 19. What effect, if any, do the Great Lakes have 
 upon the surrounding country in the production of 
 fruit ? 
 
 20. What climate seems best suited to peacfi raising? 
 
 21. what is best adapted for oranges ? 
 
 22. What fruits are produced south of the United 
 States ? What ones are produced north of the United 
 States ? 
 
 23. Where do the fruits grow farthest north, along the 
 coasts or in the interior ? 
 
17° NATURE STUDY. [December 
 
 Minerals, 
 .24. From what parts of the continent are the minerals 
 chiefly obtained ? 
 
 25. Contrast t^e eastern and western highlands as to 
 the variety and kinds of minerals produced. 
 
 26. Locate the iron mines that are now being worked 
 most extensively. Where are the copper mines ? 
 
 27. Where are the bituminous coal regions ? The 
 anthracite coal fields ? , 
 
 28. Where are the gold and silver mines ? The mines 
 of quicksilver ? Of lead ? 
 
 29. Where are the petroleum deposits ? 
 
 30. What cities are the chief agricultural depots in 
 the north ? In the south ? 
 
 31. What are the chief mining cities? What is the 
 chief coke manufacturing city in the country ? 
 
 SOUTH AMERICA. CLIMATE. 
 
 1. Use a good physical map, upon which the ocean 
 currents and winds are clearly marked. Model the map 
 to get an idea of the climatic effect of the highlands, 
 river basins, and coast lines. 
 
 2. How does the latitude of South America affect its 
 climate ? Contrast it in this respect with North America. 
 
 3. Contrast the area of South America that lies within 
 the tropics with that of North America in the correspond- 
 ing latitude ; what climatic differences must be due to 
 these contrasts ? 
 
 4. In the same way compare the temperate regions of 
 the two continents. 
 
 5. What climatic difference must be due to the differ- 
 ence in the character of the coast lines of the two conti- 
 nents ? 
 
December] GEOGRAPHY. 171 
 
 6. What modification of the climate in the tropical re- 
 gions must be due to the difference in relief ? 
 
 7. How does the position of the great Andean highland 
 affect the climate within the tropics ? 
 
 8. What is the direction of the prevailing wind within 
 thetropics ? What must be its character as to moisture ? 
 
 9. What agencies for condensing the moisture in the 
 northern half of the continent ? 
 
 10. Contrast the western slope of the Andes within the 
 tropics with the eastern ; to what are the differences 
 due? 
 
 n. What do the rivers indicate as to the amount of 
 moisture east of the Andes ? 
 
 12. What ocean current sweeps the eastern shores in 
 the temperate regioiis ? Does it set toward or away from 
 the coast ? What is the direction of the wind ? _, 
 
 13. What ocean current skirts the western coast ? 
 What wind west of the mountains ? 
 
 14. Contrast the southern half of the Pacific coast with 
 the northern ; what causes the differences? 
 
 15. Contrast and account for the differences noted be- 
 tween the eastern and the western coasts of the southern 
 half of the continent. 
 
 16. Latitude 50° north or south is noted as embracing 
 regions where fogs are prevalent ;_ can you account for 
 this ? 
 
During the winter season, opportunity should be taken 
 to study atmospheric and aqueous agencies that are con- 
 stantly but slowly changing the face of the earth by means 
 of frost and ice. The action of these may be seen and 
 studied on a large scale, if one has a chance to visit a 
 cliff, a river shore, a pond or lake beach, and quarries. 
 One or more of these can hardly fail to be convenient in 
 almost every neighborhood, and, of course, whatever is 
 present should receive the larger share of attention. In 
 lieu of'^ cliff, however, a stone wall will sometimes make 
 a good substitute ; or, what is generally better, the bank 
 of some ditch will show how the water, soaking down and, 
 then freezing, loosens masses of earth which fall off and 
 form a talus at the bottom. A small stream, a roadside 
 birook it n;ay be, will often show exactly how a river's 
 banks are clutched by the icy fingers which sooner or 
 later carry away masses of earth, rock, and drift, and de- 
 posit it elsewhere. The ice which forms under a cliff, as 
 will be illustrated by that formed along any steep bank, 
 receives considerable material dropped from above, which 
 it bears away when thawed loose from the shore. Some- 
 times in beds of finest clay, large bowlders are to be found 
 that cannot well be accounted for, except on the suppo- 
 sition that they were dropped by floating ice, which 
 doubtless bore them to the spot from some distant place. 
 When the ice breaks up after a rain, .its work in gouging 
 and cutting the banks as it is carried along by the cur- 
 
 172 
 
December] GEOLOGY. 1V3 
 
 rent may be observed. The formation of ice dams or 
 gorges, and their subsequent bursting with the effects of 
 the flood which follows, may also be noticed in any stream, 
 at almost any sharp curve, or where some obstruction 
 chokes the channel. 
 
 The freezing and thawing of the ground is also an in- 
 teresting subject for observation and study. The freez- 
 ing of the soil uplifts and loosens it, so that erosion 
 takes place more easily. By the uplifting and -consequent 
 settling movements, the roots of grasses and other plants 
 are sonietimes left exposed, and are then killed. On hill- 
 sides, the effects are still more marked. Water falling in 
 hollows above stumps, trees, and rocks, by its alternate 
 freezing and thawing tends to push such objects a little 
 farther down the slope. This will be noticed in the spring 
 after a thaw, when trees will frequently be found uprooted, 
 and rocks will be moved a little from their winter bed. 
 
 In quarries, or where rocks have been long exposed to 
 the weather, by means of cracks or seams of softer ma- 
 terial which has been washed out, water finds access to a 
 greater or less depth below the surface. When frozen it 
 operates with great force in splitting the rocks apart. 
 
 1. Examine the ground in various places and find out 
 something as to the depth it is frozen. Study the influ- 
 ences which cause variation in the depth. 
 
 2. Compare places near a building, and on the differ- 
 ent sides ; on which side is it frozen deepest ? 
 
 3. Find a place where the ground is composed of clay ; 
 compare the depth to which it freezes with a place com- 
 posed of sand. Compare both with vegetable mold and 
 loam. What precautions must you observe in the selec- 
 tion of places of observation, that your results may be 
 trustworthy ? 
 
174 NATURE STUDY. [December 
 
 , 4. How can you account for the different depths fro- 
 zen in the various places ? 
 
 5. Compare a piece of ground covered with heavy sod 
 with one without vegetation ; which is frozen deeper ? 
 
 6. What difference in the freezing of the ground under 
 a large flat stone and that around it uncovered ? In the 
 same way examine the earth under a board, and compare 
 with that under a thin stone. 
 
 7. Compare wet with- dry places ; which freeze deeper 
 and the sooner ? 
 
 8. What effect does a forest have upon the freezing of 
 the ground ? 
 
 g. Compare places covered with snow with others 
 where the snow is blown away ; how do you account for 
 the different depths to which the ground is frozen ? 
 
 10. Does vegetation increase or diminish the pcissibil- 
 ities of the soil for taking up water ? 
 
 11. Does the depth to which ground freezes seem to 
 depend upon the water it soaks up ? 
 
 12. If there is opportunity, examine a freshly plowed 
 field and compare it with one that has settled compactly. 
 
 13. Can you see any signs of weathering away of the 
 stones in the walls in different buildings? 
 
 14. Secure specimens of the, different kinds of stone,, 
 and study the closeness of the grain in each. 
 
 15. Can you see a cause for their wearing away ? Are 
 there any cracks or seams ? 
 
 16. Does a stone freeze through like a lump of 
 earth ? 
 
 17. "When broken, can you find any frost crystals be- 
 low the surface ?. 
 
 18. Do stones take ap water like the soil ? To test this, 
 dry specimens of these, taken from walls and. elsewhere, 
 
December] GEOLOGY. 17S 
 
 and weigh them ; then soak in water for awhile, dry with 
 a cloth as much as possible, and weigh again. 
 
 19. Which ones gained most weight? How do they 
 rank as to durability in walls, etc. ? 
 
 26. Test in the same way pieces of mortar or cement 
 from walls or pavements, and also pieces of brick. 
 
 21. Compare in this manner different kinds of stone, 
 such as Hmestone, marble, flint, granite, sandstone, and 
 slate ; does their durability correspond in any way to 
 their absorptive powers ? 
 
If the pupils, during the preceding months, hq.ve been 
 reasonably industrious in making their collections, they 
 will, no doubt, have found, among the rest, one or more 
 varieties of iron ore. Good examples of this valuable ore 
 may usually be picked up along railroads where it has 
 been dropped from passing trains laden with it. If 
 there- are smelting furnaces near, it may be easily ob- 
 tained in quantity, and, usually, in great variety. If 
 possible, also, secure good specimens of pig iron, slag, 
 rolled bar, cast iron, and steel. With younger pupils a 
 collection of tools, utensils, instruments, etc., would be 
 valuable in illustrating the properties of each. Sample 
 sets of these may often be procured from manufacturers, 
 who are almost always willing to furnish them to any 
 school that will give suitable space for the exhibit. 
 Much of the wall space, between the blackboard and 
 ceiling, too often bare and unsightly, may well be given 
 up to this purpose. Such displays, by no means neces- 
 sarily coniined to this one subject, will often be used 
 directly, as means of illustration in teaching ; and in- 
 directly, by their constant presence, they will, in many 
 pupils, stimulate thought and impress the mind with some 
 notion of the useful industries. 
 
 The richest ores from which iron is obtained are mag- 
 netite, hematite, and limonite, classed as oxides ; and 
 siderite and clay iron-stone, among the carbonates. 
 For specific descriptions of these, the teacher is referred 
 
 176 
 
December] MINERALOGY. 177 
 
 to " Crosby's Tables for the Determination of Minerals," 
 a copy of which every teacher should have, and to Dana's 
 Manual of Mineralogy. The latter contains a brief de- 
 scription of the different kinds. 
 
 Pupils are generally anxious to know the names of the 
 different minerals that they find, and it is proper that the 
 teacher should give the names when convinced that the 
 questions are based upon something higher than idle 
 curiosity. As a rule, the teacher should give no help 
 until sure that the pupil himself has invested some 
 thought in the subject. To insure this, a blank form for 
 the description should be given the pupil, to be filled 
 out from his own study of the mineral. (See Mineral- 
 ogy for September.) When this has been done, the 
 teacher may then give the name, and feel fairly as- 
 sured that he is helping one who really wishes to 
 know. > Of course, these blanks cannot be completely 
 filled until the preceding lessons, upon the physical 
 characteristics of minerals, have been given and under- 
 stood. But they may be used to advantage from the be- 
 ginning, the pupil filling them out as the work proceeds. 
 Simple methods of making the tests with acids and 
 the flame are described in this book under the head of 
 Mineralogy in the work outlined for January and April. 
 The teacher is referred, also, to Crosby's Tables, or any 
 manual of determinative mineralogy. The acid test 
 is easily made, and will add interest from the start. The 
 flame tests should not be attempted until the pupils are 
 familiar with the more obvious characteristics. 
 
 I. What strongly marked characteristic is common to 
 all iron ores ? 
 
 2: Find the specific gravity of the different varieties ; 
 -what one is heaviest ? 
 
178 NATURE STUDY. [December 
 
 3. Powder a small piece of each kind and test with the 
 magnet ; which is most strongly magnetic ? Are any not 
 attracted at all ? 
 
 4. What is the hardness of each ? 
 
 5. What is the difference noticed in the streak. 
 
 6. Compare as to color ; what 6olor distinguishes the 
 magnetite ? 
 
 7. What difference in shade between limonite and hem- 
 atite ? If a specimen of specular iron ore, the purest 
 variety of hematite, can be found, it will be recognized 
 by its shining mica-like blades with a metallic luster. 
 
 8. Siderite, iron carbonate, is another variety less rich 
 in iron and varying much in its appearance. 
 
 9. Examine specimens of pig iron, cast iron, wrought 
 iron, and steel. How do they differ in appearance ? Can 
 you find any evidence of crystals in any of the speci- 
 mens ? 
 
 10. What different properties do they possess ? 
 
 11. Pig iron is obtained directly from the ore by smelt- 
 ing it in a large furnace with an intense heat. The ore 
 is mingled with broken limestone and coal. By means 
 of a hot blast the iron is melted out and settles to the 
 bottom, and the lighter impurities remain on the top. 
 At intervals the melted iron is drawn off into a number 
 of molds formed in sand, called pigs. This process 
 gives the crude iron. The succeeding processes, pud- 
 dling, hammerings and rolling, are designed to rid it of 
 its impurities and give it fiber and toughness. 
 
 Cast iron articles are made by pouring the melted 
 metal into molds of the desired form. 
 
 12. How many uses can you name for cast iron ? 
 
 13. What would seem to be its most useful property ? 
 
 14. Compare it in appearance with cast steel ? 
 
December] MINERALOGY. I79 
 
 15. What useful articles are made from steel ? What 
 are its valuable properties ? A most useful character- 
 istic of steel is that it may be so treated as to have dif- 
 ferent degrees of hardness and elasticity. Take a fine 
 steel knitting-needle and bend it. On being released it 
 regains its former shape by its elasticity. Heat to red- 
 ness and plunge into cold water, and it will become hard 
 and brittle and break easily. Heat again and allow it 
 to cool slowly, and it becomes softer. The process of 
 reheating and cooling of steel is called tempering, and,by 
 it many different degrees of hardness and elasticity are 
 obtained. 
 
 16. What are the chief uses of rolled iron ? How" 
 does a freshly broken surface differ in appearance from 
 that of cast iron or steel. 
 
 17. What are its most useful properties. 
 
ZOOlOQ^. 
 
 GENERAL OBSERVATIONS, 
 
 1. What animals are you sure must remain over 
 winter with us that are not to be found abroad ? 
 
 2. Why do not all animals migrate ? Is it due to 
 superior or to less intelligence,, or to neither ? 
 
 3. What animals that you are sure must remain here 
 during the winter provide themselves beforehand with a 
 
 ' supply of food ? Will such animals lay up a store of 
 food when kept as pets ? How do you explain this ? 
 
 4. What is the character of the food with which they 
 supply themselves ? 
 
 5. Where do such animals usually stay ? 
 
 6. Are there any that do not lay up a store of food 
 which live through the winter ? 
 
 7. Where do such animals live ? 
 
 8. Can you see any reason why all animals do not store 
 food for winter use ? 
 
 9. Does the activity of animals vary with the season ? 
 Is it economical for them to remain in a state of rest at 
 certain times ? 
 
 10. What animals that remain here during the winter 
 are active ? What is their food ? 
 
 11. Do you see any relation between the activity of an 
 animal and its food supply ? 
 
 12. Do animals which remain quiet during the winter 
 take precautions against the cold ? 
 
 189 
 
January] ZOOLOGY. l8l 
 
 FOODS. DIFFERENT KINDS. 
 
 1. Do you ilotice any difference between your summer 
 and winter diet ? 
 
 2. Compare closely the character of the food which 
 makes up a meal in January with that of a meal in July. 
 What articles especially relished in July that are omitted 
 now ? 
 
 3. Does the character of the food vary with the occu- 
 pation ? Contrast the diet of a man who does physical 
 labor with that of a- book-keeper. Does your own desire 
 for particular foods vary with the kind of work you do ? 
 
 4. What influences affect the amount of food you 
 take,? 
 
 5. Can you notice any change in your weight at differ- 
 ent times? How can you account for your losing in 
 weight at times and for your gaining at others ? 
 
 6. From your own observations, what different uses 
 can you see for food ? 
 
 7. What means have you of knowing whether an article , 
 is fit for food or not ? How does the nose assist in 
 making selection ? 
 
 8. Is the taste assisted by the sense of smell ? Close 
 the eyes and hold the nostrils, and try distinguishing 
 different articles of food by tasting them. 
 
 9. What parts of the mouth are concerned in tasting ? 
 Try touching different substances to the tip and back 
 part of the tongue, to the inside of the cheek, to the 
 gums, to the under side of the tongue. Where is the 
 sense of taste most acute ? 
 
 10. Is the same part equally sensitive to different 
 substances ? Try sour, sweet, and bitter articles to 
 different points of the tongue, 
 
l82 NATURE STUDY. [January 
 
 11. By means of a mirror and a good ligbt observe 
 carefully the surface of the tongue ; note the roughness 
 and the small individual elevations which cause it. Com- 
 pare with the tongues of the dog and the cat. 
 
 12. These elevations are called papillae. The smallest 
 in size are the filiform papillae, and the less numerous 
 but larger rounded dots are the fungiform papillse. 
 Draw the tongne well forward and press it down with a 
 spoon handle and notice a V-shaped row on the back 
 part ; these are the circumvallate papillae. The papillse 
 aid in giving us the taste of food. 
 
 13. Do all articles give us the sense of taste ? Mention 
 those easily tasted. Mention some that have little ot no 
 taste. Can you taste a stone ? Salt ? What causes the 
 difference? 
 
 14. Can the acuteness of taste be cultivated ? With 
 whom is tasting a business ? 
 
 15. What influences our likes and dislikes of certain 
 tastes ? Do young children sharply di-scriminate by 
 taste ? 
 
 16. What distinction is there between gratifying t^ste 
 and satisfying the appetite ? Is the taste as acute at 
 the end of a meal as it was at the begitining of it ? 
 
 17. Are foods that are the most pleasant to the taste, 
 the staple articles of diet ? 
 
 18. What seems to be the use of the sense of 
 taste ? 
 
 19. Do all the animals that you know of have the sense 
 of taste ? Of what use would it be to grain-eating birds ? 
 Do the dry seeds differ in taste ? How do birds find 
 out what kind of seeds they want ? 
 
 20. Do the brute animals determine whether or not 
 an article is fit for food by tasting ? 
 
January] ZOOLOGY. 183 
 
 COOKING. 
 
 1. Can you see any good reason for cooking food ? 
 In what way does it change meat ? 
 
 2. Does the taste we get from a piece of meat depend 
 upon the way in which it was cooked ? 
 
 3. The art of cooking is based upon a few simple prin- 
 ciples, which are determined by certain characteristic 
 properties of the different food-stuffs, and which are ex- 
 hibited when brought into contact with heat. The prin- 
 ciples are easily understood, and the facts may soon be 
 learned, but to become an expert in this most useful 
 art nothing will take the place of long and patient 
 practice. 
 
 4. Put a small amount of the white of an egg in a test 
 tube, and subject it to a sudden and strong heat ; what 
 change does it undergo ? 
 
 5- Try again, but let the heat be very moderate, not 
 enough to cook it ; does it undergo change ? 
 
 6. Put a little more of the white of an ^gg into a tube 
 or bottle, and pour boiling water upon it ; note the 
 change. Try again, and use slightly warm water ; what 
 difference in the results? 
 
 7. The principal substance of lean meat is similar in 
 its properties to the white of an egg. Now suppose you 
 wished to roast meat ; is it desirable to keep the juices 
 within the meat, or should they be allowed to escape 
 into the pan ? 
 
 8. Which would you advise at first, a quick or slow 
 heat ? Why? 
 
 9. In boiling meat, would you put it into hot or cold 
 water at the start ? Why ? How would it be if you 
 wished to make soup ? 
 
l84 NATURE STUDY. [January 
 
 10. In frying meat, should the pan be hot or cold 
 when the meat is put into it ? Why ? 
 
 11. Why is broiled meat usually juicy? 
 
 12. Many vegetables, such as beans, peas, and pota- 
 toes, are rich in starch, which when cooked swells up 
 and becomeff dry and mealy. In this condition it is 
 more easily digested than it is when in a compact 
 mass. 
 
 13. Obtain a little wheat and dry it ; when well dried 
 pound or grind it up very fine in a mortar. Add a little 
 water and stir well. 
 
 14. Note the tenacity of the dough thus formed. It 
 is due to a substance called gluten, which is the most nu- 
 tritious part of the grain. Starch is also present. The 
 bran is rich in mineral constituents. 
 
 15. Take a lesson at home in bread making, and write 
 a description of the process. ' 
 
 16. At what point is the yeast added? Why knead 
 the dough? 
 
 17. What is the -use of the yeast ? Recall the lessons 
 on fermentation. Why does bread sometimes sour be- 
 fore it is baked ? Why must it be kept warm while ris- 
 ing ? 
 
 18. Why bake the bread ? Why is baked bread full of 
 little cavities ? Why is fresh bread less healthful than 
 dry bread ? 
 
 HUNGER AND APPETITE. 
 
 1. How does the character of one's occupation affect 
 his appetite ? 
 
 2. What seems to be essential for a regular appetite ? 
 
 3. What seems to be the function or use of the feel- 
 ing of hunger ? 
 
January] . ZOOLOGY. l8S 
 
 4. Does the character of the occupation, mental or phys- 
 ical, affect the location of the feeling ? The demand 
 for more work material in the brain worker as well as in 
 the muscle worker is made through the appropriate or- 
 gan in the feeling of hunger: We never are hungry in 
 either our heads or our hands ; both of these parts refer 
 their wants to certain parts of the alimentary canal, the 
 organ that shall speak for them. 
 
 5. Is the feeling of hunger, if not satisfied, a per- 
 sistent one ? 
 
 6. If the hunger of a brain worker is not satisfied 
 when it occurs, what feelings are likely to follow ? What 
 feelings in the case of the muscle worker ? 
 
 7. What do these feelings which succeed hunger indi- 
 . cate as to the effect of labor upon the body ? 
 
 8. At what time is the appetite sharpest ? When is it 
 least ? 
 
 9. If you retire at night hungry, are you hungry when 
 you awake ? Why is this ? 
 
 10. Are there any emotions or external conditions 
 which tend to abate the feelings of hunger ? 
 
 11. Are there any external conditions which tend to 
 increase the feelings ? 
 
 12. How is one to know when he has taken enough 
 food ? If the meal be an agreeable and an uninterrupted 
 one, the loss of the hungry feeling may, perhaps, be 
 taken as a guide to the amount of food that should be 
 eaten. But it is possible for the pangs of hunger to be 
 satisfied by a greatly insufficient amount of food, as 
 any one can testify who has been called away from a meal 
 before he has eaten the usual amount. On returning the 
 feeling of hunger is generally entirely gone ; but that 
 there was an insufficient amount of food is shown by 
 
1 86 NATURE STUDY. [January 
 
 the subsequent feelings which come when work is re- 
 sumed. It would seem that the feelings of hunger can- 
 not accompany the work of digestion ; if any food is 
 taken into the stomach, no matter how small in amount, 
 and there is a pause in the meal, digestion begins and 
 hunger is no longer felt. 
 
 13. What have you noticed about the habits of differ- 
 ent animals after they have taken food ? Notice the dog, 
 cat, horses, and cattle. Are they active or do they rest? 
 How is it with a baby ? 
 
 14. How do your own inclinations and feelings change 
 after a full meal ? Can you account for this ? 
 
 15. Do domesticated and wild animals seem to observe 
 any regularity in their times of taking food ? Observe 
 the dog and the cat. When cattle are left quietly to 
 themselves, with good pasturage, they feed with tolerable 
 regularity about four times a day. They begin very 
 early in the morning, and feed for an hour or two ; and 
 then, if the day be warm, they seek the shade or a stream. 
 Before noon they sally forth again to graze and then they 
 spend the heated noontide in the shade. Another meal 
 in the afternoon is followed by a drowsy rest in the 
 shade ; then a full supper as the sun goes down brings 
 their day to a close. 
 
 16. Can you see anything in the habits of animals or 
 in the nature of their food which affects the periods of 
 their eating ? Does the age of -the animal have any 
 effect? 
 
 0:7. How do you account for the fact that many peo- 
 ple eat but twice a day ? In considering this question 
 account should be taken of the habits and occupations 
 of the individuals. 
 
 18. Under what conditions is it better to have a light- 
 
January] ZOOLOGY. 187 
 
 lunch at midday and a full meal in the evening ? When 
 the reverse ? 
 
 19. Do you know by experience of any ill effects from 
 taking a full meal of good food just before retiring at 
 night ? 
 
 20. What reasons can you suggest for the regular re- 
 currence of the times at which food is taken by animals ? 
 
 ' Book for Reference. Humboldt Library, No. 48, Life in Na- 
 ture. Chapters on Nutrition. • 
 
During the winter occasional observations should be 
 made upon plants, and the effects of frost and freezing ■ 
 may be noted. The phenomena of growth are perhaps 
 entirely absent, though in particularly mild winters it is 
 not unusual to find dandelions in full bloom at this time. 
 A very few days of mild weather in midwinter will be 
 sufficient to coax the chickweed, in sheltered places, to 
 spread out its delicate petals. But for most part, plants 
 seem to understand the treachery of these exceptional 
 warm periods, and refuse to pay them any heed. 
 
 1. Can you find any buds that have been killed by the 
 frost? Collect a large number and get the percentage 
 killed. 
 
 2. Where are the living parts of the buds ? 
 
 3. Do the central parts of the buds freeze ? 
 
 4. What can you find about the buds that acts as a 
 protection against frost ? 
 
 5. Do any birds or other animals use the buds for 
 food? 
 
 6. In what condition are the acorns and other nuts 
 that may be found at this time ? 
 
 7. Can you find any seeds that have sprouted and 
 afterward have been killed ? 
 
 8. Have' the nuts and seeds that are covered with 
 fallen leaves been frozen ? 
 
 g. Is there any sap between the bark and the wood ? 
 10. Is there any moisture in the wood ? Does the 
 water in the twig freeze ? 
 
 188 
 
pb^sics. 
 
 AIR. 
 
 There are few experiments requiring simpler apparatus 
 than those which will well illustrate many facts and 
 phenomena relating to air ; and it may be added, there 
 are few possessing greater attraction, or that are more 
 useful in explaining many interesting phenomena daily 
 observed. From the simplicity of the apparatus, how- 
 ever, and the common occurrence of the phenomena due 
 to air pressure, etc., it must not be imagined that the 
 conception of the real character of air is one easily 
 gained. The fact that the air is invisible renders its 
 study difficult and stands in the pupil's way of getting a 
 definite idea of what it really is. Some things indeed 
 seem to lead straight to a misconception ; for example, 
 since it floats above the surface of the earth, the ordinary 
 experience of the child leads him to believe that it is 
 without weight. It will be found that very few pupils in 
 grammar schools associate the rising of water in a tube 
 " by suction " with air pressure outside, which is its true 
 cause. They almost invariably have the notion that 
 there is some mysterious kind of pulling power inside 
 the tube. The experiments, therefore, which will assist 
 in giving the correct idea, should be repeated and ex- 
 tended until the pupils have the conception that the 
 rising of a liquid in the tube, and in all similar instances, 
 
19° NATURE STUDY. [January 
 
 is due to an unbalanced pressure. The explanation of 
 
 why water will rise in a pump stock is really as simple 
 
 as the one necessary to show why one end of a see-saw 
 
 goes up if only one person is on the board. The only 
 
 reason why the former is not understood as well as the 
 
 latter is because of the difficulty in conceiving that the 
 
 air has weight. 
 
 Elasticity of Air. 
 
 1. Fill a small bottle half full of water. Through the 
 cork pass a small, tightly fitting glass tube, which should 
 reach to the bottom of the water. If the cork is not air- 
 tight, cover with wax. (See Chemistry for January.) 
 If the tube is drawn to a fine point at the Upper end, the 
 experiment will be more interesting. 
 
 2. Blow strongly through the tube into the bottle and 
 quickly remove the end of the tube from the mouth ; 
 explslin what you observe. 
 
 3. What occupies the space in the bottle above the 
 water before blowing into it? Why is it possible to blow 
 air into the bottle ? 
 
 4. Does the air which was blown into the bottle escape 
 again ? 
 
 5. Is the water all driven from the bottle ? Upon 
 what does the amount which escapes depend ? 
 
 6. Can you explain why the water is not driven out of 
 the bottle by the air already there before blowing into it? 
 
 7. Can you think of any solid body which the action 
 of the air in the space above the water resembles ? 
 
 8. Remove the cork and invert the bottle in a small 
 basin or cup of water ; does the water enter the bottle? 
 Why ? 
 
 g. Push the bottle, mouth downward, into the vessel of 
 water ; does the water fill the bottle ? Why ? 
 
January] PHYSICS. 191 
 
 10. Pass a small funnel through the cork and connect 
 it tightly with wax ; press tightly into the bottle and fill 
 the funnel with water. Can you fill the bottle with 
 water in this way ? Why ? Try filling the bottle when 
 the funnel fits loosely in the mouth of the bottle. 
 
 Pressure of Air. 
 
 1. Warm giadually a test tube or bottle in the flame 
 of the alcohol lamp, invert it, and press it closely upon 
 the back of the hand ; as it becomes cool, what do you 
 observe ? 
 
 2. Was the bottle or test tube entirely empty before it 
 was heated? What was accomplished by warming it ? 
 Recall an experiment performed in Physics in the Novem- 
 ber work to explain this. 
 
 3. What must have taken place when the bottle 
 cooled ? 
 
 4. Hold the arm in different positions ; does the bottle 
 still cling to it ? 
 
 5. Remove the bottle (noting any sound made as it 
 is pulled away) and heat it again ; invert it over a saucer 
 of water with the mouth below the surface. 
 
 6. As it cools, what takes place ? How does it differ 
 from what happens when a cool bottle is so inverted in 
 water ? 
 
 7. Boil an egg until hard and remove the shell ; heat 
 as above, or by dropping a lighted taper into it, a bottle 
 with a mouth somewhat too small to allow the egg to 
 pass through readily. Moisten the edge of the opening, 
 and when quite hot, quickly place the egg in it, the small 
 end down. 
 
 8. Consider what takes place as the bottle cools. If 
 the opening is of the proper size the egg will pass into 
 
192 NATURE STUDY. [January 
 
 the bottle. By recalling previous experiments (see 
 Physics for November), devise an easy means of getting 
 the egg out of the bottle without injury to either. 
 
 9. Bend a glass tube, the size of a lead pencil, into 
 something like a U-shape so that each arm shall be three 
 or four inches long. Immerse completely in water until 
 filled. Fit a piston, made by wrapping a greased string 
 or strip of cloth around a stick or wire, to one end, and 
 remove the tube until half-way down and then withdraw 
 it. Watch the water in the tube. 
 
 10. Repeat the experiment, holding the tube in dif- 
 ferent positions — upside down, horizontal, etc. 
 
 ti. Hold the tube upright, and push the piston down 
 -half-way ; see that the other arm of the tube stands level 
 full of water. Place a finger tightly over this end and 
 slowly withdraw the piston. Does the water follow the 
 piston ? Remove the finger and note the result. In this 
 exercise note whether or not the piston is air-tight ; how 
 can you find this out ? 
 
 12. Repeat the experiment suggested in (ii), and with- 
 draw the piston entirely from the tube ; can you account 
 for what takes place ? 
 
 13. Place a small tube of any kind between the lips, 
 and, with the finger over the other end, suck the air 
 from it and apply the tongue to the end ; what takes 
 place ? Remove the finger and note the difference. 
 
 14. Close the lips and try drawing or sucking the 
 cheeks in between the teeth ; when well drawn in, what 
 is the effect of slightly opening the lips ? 
 
 15. Using the tube mentioned in (9), immerse it partly 
 in an upright position in water ; does the water rise in 
 it? Lift it out of the water slowly, and watch the water 
 inside the tube. 
 
January] PHYSICS. 193 
 
 i6. Immerse it again in the same way, close the upper 
 end tightly with the finger, and remove from the water ; 
 what difference do you see ? Remove the finger and 
 notice what takes place. 
 
 17. Fill a large bottle with a small opening level full 
 and invert it; does the water run out? If a small- 
 necked bottle cannot be obtained, get one with a good 
 cork, throughwhich a small hole may be drilled. 
 
 18. Sink a bottle or a tube below the surface in a 
 vessel of water, and let it lie on its side until it is com- 
 pletely filled ; turn it up mouth downward, and raise it 
 so that the mouth is just below the surface. Is there any 
 water still in the bottle ? 
 
 19. Can you give any reasons for what has taken place 
 in the foregoing experiments ? In the first one did the 
 bottle make any- mark upon the hand ? How could you 
 make such a mark with the bottle without first heating 
 it ? Try pressing the bottle firmly against the hand for 
 some time. 
 
 20. Why does heating the bottle first enable the water 
 to rise in it, as in (6), when it does not do so as in (8) 
 under elasticity ? 
 
 '21. Is the water drawn up into the bottle, or is it 
 pushed into it ? Is there anything inside to draw it ? Is 
 there anything outside to push it ? 
 
 22. Is the egg in (7) drawn into the bottle or pushed 
 into it ? What is there to draw or push ? 
 
 23. Can you make the air in the bottle push the egg 
 out again ? 
 
 24. When the piston is pushed down in (9), is the 
 water pushed or drawn out of the opposite end ? 
 
 25. While the piston is being withdrawn, is the water 
 when following it being pushed or drawn? 
 
194 NATURE STUDY. [January 
 
 26. Does the water refuse to follow the piston in (11) 
 while the finger remains on the opening in the tube? 
 Has the piston any means of drawing it ? If the piston 
 is not air-tight, how will it affect the results ? 
 
 27. If possible, procure a thick glass tube thirty inches 
 long having a bore of about one-fourth of an inch, and 
 also a small bottle of mercury. Stop one, end of the 
 tube and by means of a small funnel fill it with mercury. 
 Place the thumb over the upper end, and then invert in 
 a small cup of mercury. Does the mercury run out? 
 Measure the height of the column. If a barometer be 
 at hand compare the height of the mercury in the tube 
 with it. 
 
 28. Repeat the experiment, using water instead of 
 mercury. What difference between the water and the 
 mercury ? Mercury is thirteen and a half times as heavy 
 as water : how high a column of water would be sustained 
 by a pressure equal to that in (26) ? 
 
 29. What force holds these fluids up in the tube ? 
 Explain how the same force has acted in previous exer- 
 cises. 
 
 30. What use can you see for the barometer? Why 
 does the mercury sometimes stand higher than at others 
 in the barometer ? 
 
 31. Why must the barometer tube be closed at the 
 upper end ? Is there air in the space above the mer- 
 cury ? Why ? 
 
 32. Why is it that the mercury of the barometer enables 
 us to measure the pressure of the air and that in a' ther- 
 mometer measures temperature ? 
 
 33. From the foregoing experiments can you tell in 
 what directions air presses ? 
 
 34. The actual pressure of the atmosphere is about 
 
s January] PtlVStCS. 19? 
 
 fifteen pounds to each square inch of surface ; calculate 
 the pressure on top of a desk ; of a table ; on the floor 
 of a room. Why does not this great weight crush every- 
 thing beneath it ? 
 
 35. Why are our bodies nol crushed by this weight, 
 which on an average-sized man equals twenty tons ? 
 How does it affect people who ascend to great heights 
 in balloons ? Can you account for this ? 
 
 THE PENDULUM. 
 
 To follow the work on the equilibrium of bodies 
 planned for the previous month, an interesting series of 
 observations and experiments may be made with the 
 pendulum. They will afford fine opportunity for the 
 pupils to develop skill in making and delicacy in manip- 
 ulation. 
 
 1. Suspend from any convenient support a large bullet 
 by means of a small thread, two feet long ; when the 
 bullet is drawn a little to one side of its position of rest, 
 can you see why it swings ? 
 
 2. What kind of a path does the ball describe in 
 swinging? It is called an arc. When the ball is at one 
 extremity of the arc, what two forces are acting upon it? 
 Note carefully the line of direction of each force. Com- 
 pare with these two lines the direction through which 
 the ball really moves at each point in the arc. Why 
 does the pendulum begin to swing in the opposite direc- 
 tion ? 
 
 3. An oscillation or vibration is the motion from one 
 extremity of the arc to the other. The angle measured 
 by the arc is the amplitude of vibration. The time it 
 takes the ball to move through this arc is the time of 
 vibration. 
 
19^ JSTATURM study. [January 
 
 4. Swing the penciulum through a short arc and note 
 the number of vibrations to a minute. Vary tlie experi- 
 ment, making the arc longer and shorter, and count the 
 vibrations per minute ; what fact do you learn ? 
 
 5. Make another pendulum of same length, but use a 
 cork ball of same size as the bullet. Compare the oscil- 
 lations of the two pendulums. 
 
 6. Suspend another bullet by a shorter thread ; how 
 do its oscillations compare with the first one rqade ? 
 
 7. How long must it be so that it will vibrate just 
 twice as fast? Compare the length of the two. 
 
 8. What do you notice about the times of vibration and 
 the miviber of vibrations in a given time of the two pen- • 
 duluras ? Try those of other lengths. 
 
 9. Can you make one which will vibrate seconds ? 
 How long is it? What. does the pendulum of your clock 
 at home vibrate ? 
 
 10. What advantage in using the pendulum in meas- 
 uring time ? What is the use of the spring or wfeights 
 and the other parts of a clock? 
 
 11. What means were used for measuring time before 
 clocks were invented ? 
 
 12. Suppose a clock runs too fast, how can you prop- 
 erly regulate it ? Why ? Why do the extremes of winter 
 and summer affect the running of a clock ? 
 
 13. Suspend bars of wood having same length, but of 
 different shapes, such as conical, one suspended by the 
 base and the other by the apex, prismatic, spindle-shaped, 
 etc., and observe the oscillations of each ; can you ac- 
 count for the variations ? 
 
 14. Which is really the longest pendulum mentioned 
 in (13)? Which the shortest ? How can you decide ? 
 
(tbemistr^. 
 
 HYPROGEN. 
 
 In making hydrogen, and performing experiments 
 with it, the pupils should follow with great eare all the 
 directions given. It is easier and much better to pre- 
 vent an accident in laboratory work than it is to repair 
 the niischief done by one. The pupils should be trained 
 to make themselves certain of each step in any process 
 before taking it. When hydrogen is mingled with air or 
 with oxygen, the mixture is explosive. Upon this fact are 
 based all the precautions necessary to be observed iiithe 
 making of hydrogen, and in its management in the fol- 
 lowing exercises. With this single point in mind, it 
 is easy and practicable for pupils to perform a num- 
 ber of interesting and profitable experiments. It is 
 doubtful, however, if it be advisable for the teacher to 
 undertake such a course of experiments when the pupils 
 cannot do all or the essential part of. the work for them- 
 selves. It should be planned to have the pupils do. It 
 is not denied that they may be instructed by what 
 they see and hear the teacher do ; but there is so much 
 that the pupils can do for themselves, and the power they 
 gain by doing, by working out patiently all the details for 
 themselves, is so much greater, that it is nothing less than 
 deprivi,ng them of their rights to fail in meeting their 
 capabilities for work. Teachers are as far astray when 
 
 197 
 
198 MATVRB STUDV. [January 
 
 they do what the pupils should do, as they are when they 
 assume to think for them. 
 
 Materials Needed. 
 
 1. Procure a wide-mouthed bottle, holding two to four 
 ounces, for each pupil. Fit a piece of glaiss tubing, three 
 or four inches long, through the cork ; the upper end of 
 the tube should be drawn to a point. To do this, heat 
 the tube an inch from the end in the flame until soft, and 
 then pull it out to a fine thread and break it. The hole 
 in the upper end of the tube should not be larger than a 
 small pinhole. The cork, unless it be a good one, 
 should be well coated with wax. An excellent wax for 
 the purpose may be made and applied as follows : Hard 
 paraffine, two parts ; soft paraffine, one part ; melt to- 
 gether, and, while hot, pour a few drops into a vessel of 
 cold water ; remove these quickly while still warm, and 
 apply to the cork. A coating of tallow on the cork will 
 answer the purpose. 
 
 2. The bent tube used in making oxygen in previous 
 lessons ; a short piece of rubber tubing ; a clay pipe. 
 
 3. A piece of glass tubing, about half an inch in diame- 
 ter and two feet long. 
 
 4. A handful of scraps of zinc. 
 
 5. Hydrochloric acid. 
 
 6. Test-tubes, or small two-dram bottles. 
 
 Experiments. 
 I. Clip the zinc scraps into small pieces, and put 
 enough into the wide-mouthed bottle to, at least, cover 
 the bottom. Cover with water and add the acid until a 
 brisk bubbling takes place. Allow this to continue three 
 or four minutes till the air in the bottle has been driven 
 out. 
 
January] CHEMISTRY. 199 
 
 2. Press tightly into the bottle the cork with the tube 
 in it. What evidence is there of a change taking place 
 in the bottle. Wrap a towel or cloth around the bottle 
 as a precaution against a possible explosion. This will 
 prevent injury Trom flying pieces of glass. 
 
 3. Apply a lighted match to the tip of the glass tube. 
 This is called the philosopher's candle. What evidence 
 have you of the character of the work being done by the 
 acid and zinc ? 
 
 4. Are the bubbles formed inside the bottle filled with 
 air ? 
 
 5. Feel the sides of the bottle ; is the gas coming out 
 at the top of the tube steam? How can you decide this 
 question ? 
 
 6. Is the gas oxygen ? Is it carbon dioxide gas ? 
 
 7. How does the flame differ from that of ordinary 
 gas or a lamp ? 
 
 8. Hold a small piece of irpn wire in the flame for a 
 short time, and then, when cool, hold it for the same 
 length of time in the flame of a candle ; what differ- 
 ence in the result ? 
 
 g. How does the light-giving power of the flame differ 
 from that of a candle ? 
 
 ro. Take the large glass tube and lower it gently over 
 the flame ; with the flame at different heights inside the 
 tube, can you detect any sound ? 
 
 ir. While the sound is being produced, watch the 
 flame closely ; what changes, if any, does it undergo? 
 
 12. Can you account for the sound ? The full consid- 
 eration of this question had probably better be referred 
 to some future time when the subject of sound is being 
 studied. If possible, try tubes having different diameters 
 and of different lengths. 
 
200 NATURE STUDY. [January 
 
 13. What forms in the upper part of the tube when it 
 is held over the flame ? Can you account for it ? 
 
 14. Extinguish the flame ; hold a test tube inverted 
 over the' tube through which the gas is escaping. After 
 two or three minutes, remove the-test tube, and, still keep- 
 ing it inverted, apply a lighted match to its mouth. 
 Compare the result with a similar experiment performed 
 with oxygen. 
 
 15. In the same manner fill a test tube and remove it 
 and turn the mouth upward ; after a minute apply a 
 lighted match to the mouth. Is there any evidence of 
 gas in the tube ? ' 
 
 16. Fill the test tube again, remove, and keep it invert- 
 ed. Bring the mouth of the tube close to the mouth of 
 a second tube, also inverted, and incline it until the 
 mbuth of the first is turned upward under the second. 
 Apply a lighted match to the mouth of the second while 
 it is still inverted. These operations should be per- 
 formed as quickly as possible. 
 
 17. Connect the glass tube by means of the short rub- 
 ber tube with the stem of a clay pipe. With some strong 
 soapsuds blow some bubbles. When they break loose 
 from the pipe touch them with a lighted taper. Do not 
 apply the flame to the pipe bowl, nor to the bubbles 
 until they are entirely free from it. 
 
 18. What do the experiments, 14 to 17 inclusive, show 
 you as to the character of this gas ? The gas formed is 
 called Hydrogen. Its symbol is H. 
 
 19. In what respects is hydrogen like air ? How does 
 it differ from air ? 
 
 20. Compare it with the CO, (read carbon dioxide) 
 that was studied in November. 
 
 21. How do the pouring processes by which the 
 
January] CHEMISTRY. 201 
 
 gases were transferred from one vessel to another 
 differ ? 
 
 22. Compare the effects of CO^, O, and H, and air, 
 upon the lighted match. 
 
 23. Compare the methods by which CO^, O, and H are 
 obtained ; in what respect is the process the same in all 
 the cases ? 
 
 24. Examine the contents of the bottle after the bub- 
 bling has ceased ; is the zinc changed ? What kind of 
 a change has taken place ? 
 
 25. Try some of the fluid which remains upon fresh 
 zinc ; is it like the acid you started with ? 
 
 26. Will fresh acid continue to act upon the solids left 
 in the bottle ? 
 
 Book for Reference. Humboldt Library, No. 99, Nature 
 Studies, chap. i. 
 
flDeteoroIog^. . 
 
 1. In which month during the period included in your 
 record has the temperature been most diminished ? 
 Can you see a reason for this ? 
 
 2. In which month, in the same period, has there been 
 the least variation in temperature ? 
 
 3. Does the rate of variation in temperature corre- 
 spond in any way to the variation in length of the noon 
 shadow ? 
 
 4. Judging from the slant of the sun's rays, are we 
 receiving more or less heat from the sun than we re- 
 ceived in December ? What does the thermometer tell 
 us? 
 
 5. What has been the prevailing wind for the month ? 
 Compare with previous months. 
 
 6. Is the wind more or less variable than it was during 
 the autumn months ? 
 
 7. How has the prevailing wind affected the tempera- 
 ture ? 
 
 8. What wind has accompanied the lowest tempera- 
 ture ? The highest ? 
 
 9. What was the greatest range of temperature noted 
 in any week ? What was the range during the month ? 
 
 10. How does the number of rainy or snowy days com- 
 pare with that of December ? 
 
 11. How does the amount of rainfall compare with 
 previous months ? 
 
January] Mi: TRORdL 60 V. 40^ 
 
 12. From what direction do tlie rains come? Ttie 
 snows ? 
 
 13. Do you notice any uniform variation in tempera- 
 ture before, during, and after a storm ? 
 
 14. At wliat temperature has the most snow fallen ? 
 The heaviest rains ? 
 
 15. Does the size of the snowflakes vary with the tem- 
 perature ? 
 
 16. Does the barometer in any way indicate uniformly 
 the approach of a storm ? 
 
 17. Do rain and snow storms affect it in the same way ? 
 
 18. When does it show uniformly the greater height, 
 on warm or cold days ? What has been its greatest range 
 in each week and during the month ? 
 
 19. How do the clouds during this month compare in 
 kind and elevation with those of the previous months? 
 
 20. What differences, if any, do you notice between a 
 rain cloud and a snow cloud ? 
 
 STUDIES OF SIGNAL SERVICE MAPS. 
 
 21. What quarter of the United States has had the 
 Low Area most frequently during the month ? The High 
 Area? 
 
 22. What region has been visited by the severest 
 storms ? Compare with December in this respect. 
 
 23. What has been the most southern point reached 
 by the zero isotherm during the month ? What range of 
 latitude was crossed by this isotherm ? 
 
 24. What was the most southern point reached by the 
 isotherm 32° ? What range of latitude did it cover ? 
 
 25. Can you determine the direction of the great 
 storms during the month ? In what regions have they 
 originated ? 
 
204 Nature study. tJ^nuaiy 
 
 26. What places stand on the snow line during this 
 month ? Compare with December. 
 
 27. Where does the snow line bend farthest south? 
 Farthest north ? What is the range of latitude covered 
 by the snow line ? Can you see any reason for this vari- 
 ation ? 
 
 28. What influence have the Great Lakes had upon 
 the snow line ? The mountain systems ? The river 
 valleys ? 
 
 29. How does the climate west of the Rocky Moun- 
 tains differ from that on the east ? 
 
 30. Contrast the Atlantic coast with the Mississippi ' 
 valley. 
 
 Book for Reference. Humboldt Library, No. gg, Nature 
 Studies. Chapter on Snow. 
 
Hstronomi?. 
 
 The problems in this subject which offer themselves 
 for study in the changing seasons and recurring day and 
 night, and through the observation of the stars and the 
 planets, have been of deep interest to mankind since the 
 earliest times. They present every degree of difficulty ; 
 the simplest lie within the grasp of the primary pupil, 
 while the solution of those most abstruse has engaged the 
 highest intellectual power' of the human mind. 
 
 It is not necessary to take up all the problems that 
 may suggest themselves during any month ; but enough 
 should be considered to give a meaning to the daily 
 meteorological record that has been kept, so that keep- 
 ing it may not sink to the level of lifeless routine work. 
 If the records have been faithfully made, by this season 
 abundant data will be at hand, which will form a good 
 basis for most interesting' work. 
 
 1. How is the length of day and night changing this 
 month ? Is the change the same that occurred last 
 month ? 
 
 2. Compare the rate of change during, the first week 
 with that during the last one. Can you account for the 
 difference ? 
 
 3. Compare the rate of change during January with 
 the corresponding weeks in December. Can you ex- 
 plain why the rate is much the same ? 
 
 4. Is the period of daylight this month being length 
 ened by additions at both morning and evening ? 
 
 805 
 
io6 NATURE ^TUDV. [January 
 
 5. At which time is the greatest addition made ? Why- 
 should the additions not be the same at both ends of the 
 lighted period ? 
 
 6. Refer to the record for previous months ; is there 
 a corresponding difference while the day is growing 
 shorter ? Make use of a globe in trying to find out why 
 the lighted period is not either increased of diminished 
 by equal times, morning and evening. 
 
 7. When is the increase or decrease in day's length 
 nearly equally divided between morning and evening ? 
 When is it most unequally so divided ? 
 
 8. Examine the noon marks made this month. (See 
 description of apparatus in September work.) How do 
 the spaces between the marks compare with those of 
 previous months ? 
 
 9. What does the variation in the length of the space 
 indicate ? Try to illustrate by use of a globe. 
 
 10. Is the limit of the shadow moving in the same 
 direction as it did last month ? What is the meaning 
 of this ? Is it moving at the same rate ? Show why, 
 using a globe, this is so ? 
 
 11. Can you tell from a study of the noon marks 
 whether we are receiving more or less heat from the sun 
 than we received last month ? Consult your meteoro- 
 logical record a:nd note the variation in the temperature 
 this month. 
 
 12. What is the smallest angle that the sun's rays at 
 noon have made with the horizon ? Use the instrument 
 described in the September work for making the measure- 
 ment. 
 
 13. Try to show why this angle is smallest during this 
 part of the year. 
 
 14. What effects depend upon the size of this angle as 
 
January] ASTRONOMY. 207 
 
 a cause ? Is the angle increasing or diminishing at pres- 
 ent ? 
 
 15. What effects are noticeable at present that are due 
 to its changing size ? Is it affecting temperature ? 
 Why? 
 
 16. In which of the previous months was the angle 
 about the size that it is the last of January ? How does 
 that month compare with January as to temperature, 
 length of day and night, etc. ? Try to explain why they 
 are alike in some respects and different in others. 
 
 17. How are the points at which the sun rises and sets 
 moving on the horizon at present? Can you show why 
 this is so, usitig a globe ? 
 
 18. What is the greatest variation in the time of the 
 rising or setting of the moon on two successive days ? 
 
 19. Can you think of the conditions necessary that 
 would cause it to rise at the sametime every evening ? 
 
 20. Under what conditions would the moon rise in the 
 west and set in the east ? Would its appearance change 
 during the night ? (This is true of one of the moons of 
 the planet Mars.) 
 
 21. The planet Venus (see Astronomy for September) 
 moves around the sun in two hundred and twenty-five 
 days. Can you explain why this planet has changed 
 from an evening to a morning star ? Try to see the 
 planet moving in its orbit. and in its proper relation to 
 the earth and sun. Use symbols sparingly and only to 
 illustrate, not to take the place of the real objects. 
 
 22. How long does it shine as morning star and as 
 evening star respectively ? 
 
 23. Suppose the earth and Venus are on the same side 
 of the sun and in a line with it, what will be the position 
 of the three bodies at the end of one year ? 
 
2o8 NATURE STUDY. [January 
 
 24. Can Venus ever appear to us except as a morning 
 or an evening star ? 
 
 25. Will she exhibit phases corresponding to those of 
 our moon ? 
 
 26. In what position will we see the largest part of the 
 disk ? In what position will we see the smallest part 
 of it ? 
 
 27. Constellations the same as last month ; how have 
 they changed their positions ? 
 
 Books for Reference. Humboldt Library : No. 14, Wonders 
 of the Heavens. No. 20, The Romance of Astronomy. No. i, 
 ■ Light Science for Leisure Hours, Chapter on Venus. 
 
(Beograpb^. 
 
 SOUTH AMERICA. PRODUCTIONS. 
 
 The pupils should model a relief map, and with this 
 before them endeavor to work out the reason for the 
 character of the various productions, as far as they 
 are results of the climatic conditions of latitude, eleva- 
 ,tion, winds, rainfall, coast line, and ocean currents. 
 
 1. "Judging from the range of latitude covered by the 
 continent, what contrasts must be expected in animal 
 and vegetable productions ? 
 
 2. Compare South America with North America in 
 this respect. What different conditions will tend to pro- 
 duce contrasts- in the two continents in corresponding 
 latitudes ? 
 
 3. What contrasts in productions would you expect to 
 find in South America in the equatorial regions? 
 
 4. Is it possible that the productions belonging usually 
 to the- temperate regions may be found within the 
 tropics ? 
 
 5. 'What_ contrasts would you expect to find on the 
 opposite sides of the Andes Mountains within the 
 tropics .? 
 
 6. How must the productions of the Atlantic and the 
 Pacific coast lines differ within the tropics ? 
 
 7. Would you expect much contrast between the At- 
 lantic coast line and the interior in the equatorial region ? 
 
 8. Would you expect a similarity or contrast between 
 
 209 
 
2IO NATURE STUDY. Qanuary 
 
 the Pacific coast of South America and that of North 
 America ? 
 
 9. What are the most active influences which deter- 
 mine the productions on these coasts in the two conti- 
 nents ? 
 
 • 10. What must be the character of the Pacific coast 
 productions of South America in the temperate zone ? 
 
 11. Do you see any reas6n for their being different on 
 the eastern side of the mountains ? 
 
 12. Contrast this region with the corresponding lati- 
 tude of North America. 
 
 - 13. Where are the fertile river valleys in South 
 America ? 
 
 14. Locate on molded map the great forest area of the 
 continent. What are the conditions favorable for it ? 
 What valuable woods are obtained from this great forest 
 region ? Read a description of the Amazon river 
 basin. 
 
 15. How do the climatic conditions favor the great 
 grass plains of the Orinoco basin, the Llanos ? Are the 
 same conditions favorable to forests? 
 
 16. Where else are there grass regions in South 
 America ? 
 
 17. To what regions of North America do they corre- 
 spond ? 
 
 18. Locate on the map the region from which spices, 
 gums, and medicinal plants are obtained. 
 
 19. Locate in the same way the coffee-growing 
 region. 
 
 20. What do the exports from Buenos Ayres tell as to 
 the productions of the surrounding country ? Compare 
 with the exports of Rio Janeii"o. 
 
 21. Locate the. regions of greatest mineral wealth. 
 
January] GEOGRAPHY: 211 
 
 What minerals are found in the Andes Mountains ? In 
 the Brazilian highland ? 
 
 22. What are the chief cities of the mining regions? 
 Read the Story of the Incas and the history of the con- 
 quest of Peru. 
 
 Books for Reference. Guyot's Physical Geography. Humboldt 
 Library, Nos. ii and I2. The Naturalist on the River Amazon. 
 
(Beologi?. 
 
 The observations of the effects of frost and freezing as 
 agencies that are at work during the winter season in 
 changing the face of nature should be continued this 
 month along the lines commenced in December. The 
 experiment suggested under Physics for November, 
 showing the expansive force of freezing water, may with 
 profit be recalled or repeated and applied in this con- 
 nection. Examination should be made of the soil in dif- 
 ferent places to determine the depth to which the ground 
 is frozen under various conditions. It will be a matter of 
 interest and profit at this time, while outdoor work is 
 impracticable, on account of the inclemency of the season, 
 to consider the nature of fossils, and to try to read some of 
 the earth's history recorded by them. The early ideas 
 as to the origin and meaning of fossils were as monstrous 
 as they now seem curious and amusing. Of all the ob- 
 served acts in nature which man has, from time to time, 
 endeavored to reconcile to his preconceived notions of 
 the origin and history of this world, nothing has proved 
 more refractory than these foot-prints of a long bygone 
 age. Although it required some hundreds of years for 
 early scientists to get the first glimpse of the truth con- 
 cerning fossils, yet so obvious are the general facts of 
 their history, it was only necessary for the mind to ap- 
 proach the subject unbiased by preconceived notions 
 and beliefs to have their true character recognized. The 
 course of early inquiries into the nature of fossils affords 
 
January] GEOLOGY. 213 
 
 one of the strongest illustrations given on the page of 
 history of how one's prejudice or belief may become an 
 insurmountable barrier between him and the simple truth. 
 Even children of primary grades will, without prompting, 
 reason correctly about the origin of fossils, though of 
 course they lack almost totally the idea of the time in- 
 volved. 
 
 The fossil in itself is a matter of comparatively little 
 interest, but when it is used as a key to unlock the se- 
 crets of the past ; when through it the child calls up a 
 great picture of the world and nature as they mu;t have 
 been when it was a living thing ; when, with it in hand, 
 he sees the succeeding ages roll by, each with a charac- 
 ter of its own, then it becomes one of the most powerful 
 means at the teacher's command for broadening and 
 strengthening his pupil's conception of the universe. 
 The teacher must carefully avoid the mistake of being in 
 ~ too much haste. The idea to be attained is vast, and is 
 destined to forever grow. Let the pupil have ample 
 time to fill in his picture of those distant ages with land, 
 water, sunlight, darkness, plants, animals, air, blue sky, 
 lowering clouds, lightning, thunder, rain, snow, ice, and 
 everything that the existence of that one living thhig, 
 which we now know as a fossil, implied. Without due 
 deliberation and thought, something will be omitted which 
 will mar the symmetry of the creation and spoil the 
 beauty of the scene. 
 
 For an excellent resume of the early theories regard- 
 ing fossils, the teacher is referred to Lyell's Principles of 
 Geology, vol. i, page 33, et seg. 
 
 1. Examine the ground in the locations observed last 
 month ; has it been frozen to greater depth ? 
 
 2. If opportunity offers, notice a trench dug through 
 
214 NATURE STUDY. [January 
 
 the Street ; is the ground frozen deeper under the cobble 
 stones than it is under the sod ? Can you account for 
 the difference ? 
 
 3. Can you find any stones that are being crumbled by 
 frost ? 
 
 4. Where is the ground frozen to a greater depth, un- 
 dei: the trees or in an open space ? Where there is sod 
 or where the ground is bare ? 
 
 5. Can you notice any differences in freezing that you 
 know are due to differences in soils ? 
 
 6. Among the fossil plants that are perhaps most 
 easily obtained by pupils are some ojf those, ferns it may 
 be, of the Carboniferous or Coal Period. The following 
 questions and suggestions refer specially to such a fossil, 
 though they may readily be adapted to any fossil plant. 
 These, or at least the impressions of them, are frequently 
 found in the lumps of coal in the bin, and pupils should 
 watch fqr them. 
 
 7. Is there any doubtas to what has left its imprint 
 upon the stone or coal ? What are the marks that make 
 you certain of the correctness of your answer ? 
 
 8. Does it in any respect resemble any plants of the 
 present time ? Can you tell what part of the plant 
 it is ? 
 
 9. Is the fossil under examination the original plant, 
 or a cast of it ? By cast this is meant : that the space 
 that was once occupied by the plant has been filled with 
 a stony substance that bears the shape and marks of the 
 once living thing. If neither a cast nor the original sub- 
 stance, can you make out whether it is more than merely 
 the imprint of some plant ? 
 
 10. Can you discover any evidence that the leaves were 
 veined like those of the present day ? 
 
January] GEOLOGY. 2 IS 
 
 11. Can you form any idea as to the size the plant 
 must have been ? 
 
 12. From what you know of ferns which you have seen, 
 within what range of heat and cold is it likely that this 
 plant lived ? 
 
 13. Was the cold as severe as that of Greenland at 
 present ? Is it possible that snow may have fallen where 
 it grew ? Did it rain there ? Do you suppose the sun 
 shone upon it ? , How much warmer may the sun have 
 shone upon it than it shines upon us in summer? 
 
 14. Do you know where it was found ? Do ferns now 
 grow in that region ? How viay that region have differed 
 from its present condition when the fossil grew there ? 
 
 15. Is it likely that it grew on a high mountain ? Did 
 it grow in a desert ? Could it have grown in a 
 marsh ? 
 
 id. Is there evidence as to whether it grew in a forest 
 or in open fields ? What would you suppose concerning 
 the fertility of the soil that produced it ? 
 
 17. Can you tell whether or not it belonged to a plant 
 thatched its leaves? Was this fossil decayed before it 
 fell to the ground ? 
 
 18. Do you think this fossil plant bore as many leaves 
 as our plants do at present ? Were plants growing as 
 thickly on the ground as they do now? 
 
 19. How does it happen that fossil leaves are not 
 more abundant? Are the leaves that you noticed fall 
 last autumn likely to become fossilized ? 
 
 20. Did this fossil leaf decay after falling to the ground 
 as soon as most leaves do that you have noticed ? 
 
 21. What must have happened soon after it fell, which 
 started it on the way to become a fossil ? 
 
 22. Which is the more likely, that it fell in a wet place 
 
2l6 NATURE STUDY. [January 
 
 or in a dry one ? In which place would it probably be 
 more quickly covered ? 
 
 23. In which kind of covering, wet or dry, would the 
 more perfect imprint be made ? In which kind would 
 the leaf be the longest preserved ? In which would the 
 imprint be the better preserved before the rock hard- 
 ened ? 
 
 24. Was it covered with fine or coarse material ? 
 
 25. If you think it was buried in a dry place, what 
 agency, probably, did the work ? Can you by digging 
 down into the soil find leaves that are as perfect as this 
 one ? 
 
 26. On the supposition that it fell into a swamp, or 
 into water, by what means do you think it could have 
 been buried ? 
 
 27. If you think it fell into water, can you find any 
 evidence as to whether it was running or standing 
 water ? 
 
 28. If the fossil you have is a cast of the plant form, 
 how was that cast made? Would it be more easily 
 formed in dry or in wet ground ? 
 
 29. In case you have but the imprint, can you tell what 
 has become of the plant ? Why was the imprint not 
 destroyed ? 
 
 30. If your fossil came from a coal mine, or near it, do 
 you know what thickness of earth there wasaboveit? 
 How deep are some of the coal mines that you have seen 
 or read about ? 
 
 31. Are there layers of solid rock above the coal 
 seams ? 
 
 32. In what way, most likely, was this great covering 
 deposited ? 
 
 33. If this mass of earth and rock was deposited by 
 
January] GEOLOGY. 217 
 
 water, what change must have come over the region where 
 the fern grew ? What can you infer about the depth of 
 the water ? 
 
 34. Can you find any evidence that will show whether 
 the change was gradual or sudden ? 
 
 35. What is the most reasonable supposition that you 
 can make which will account for the region where the 
 fossil grew becoming covered with water. 
 
 36. What other change in the region must have oc- 
 curred after the mass of earth was deposited ? 
 
 37. What supposition can you make which will explain 
 how the water was removed ? 
 
 38. Is there any evidence of more than one sinljing, 
 and one elevation of the land ? 
 
 39. .After the water finally disappeared, by what means 
 do you think the fossil became exposed, if it was found 
 on or near the surface ? What agencies that you know 
 of are now at work that would tend to gnaw away its 
 covering ? 
 
 40. In looking back over the possible history of the 
 fossil, can you form any estimate of the length of time 
 included in it ? 
 
 41. In any region that you maybe familiar with during 
 . the past few years, has there been any perceptible depth 
 
 of material deposited ? What has placed it there ? 
 
 42. Has there been any perceptible deposition in any 
 lake, large or small, that you have had opportunity to 
 observe ? 
 
 43. Is there any way of telling how long it took the 
 water to gather to this region or recede from it ? 
 
 44. It has been estimated that the Mississippi River 
 carries down enougii sediment each year to cover a 
 square mile two hundred and sixty-eight feet deep. At 
 
2l8 NATURE STUDY. [January 
 
 that rate, how long would it take that river to remove a 
 layer one foot thick from its basin ? 
 
 45. At the same rate, how long would it take to expose 
 the fossil after the wat§.r had receded, supposing it to 
 have been buried five hundred feet deep ? If each of the 
 other periods in the history of the fossil were as long, 
 what would be its age ? 
 
 Books for Reference. Humboldt Library : No. 6, Town 
 Geology. No. 38, Geological Sketches, chap. vii. 
 
If the pupils have been industrious in collecting speci- 
 mens of the various. kinds of rocks and minerals of the 
 neighborhood, it will be interesting to examine them with 
 a view to learning something of their chemical proper- 
 ties. A few cents' worth of hydrochloric and sulphuric 
 acids in separate bottles will be all that is necessary. If 
 these cannot be obtained, use strong vinegar. 
 
 1. Powder a small amount of limestone and put it into 
 a small bottle or test tube, add a little hydrochloric acid, 
 and note the result. Gently warm the 'test tube over the 
 lamp ; what difference is noted ? 
 
 2. In the same way try the limestone with dilute sul- 
 phuric acid ; compare with the changes that occurred 
 with hydrochloric acid. Dilute the sulphuric acid with 
 five or six times its bulk of water, and allow it to cool 
 before using ; add the acid to the water, allowing it to 
 run slowly down the sides of the tube. 
 
 3. In a similar manner treat a piece of marble and 
 compare with the limestone. 
 
 4. Take some small pieces of Shells, those ^f oyster or 
 clam, and treat with acid ; how are they like the stones ? 
 If it can be obtained, try in the same way a piece of chalk 
 — not crayon. What is the result ? 
 
 5. The bubbling noticed when the stones were placed 
 in acid is called effervescence. Stones which dissolve in 
 acids with effervescence, a gas being formed, are said to 
 
220 • NATURE STUDY. [January 
 
 be calcareous. They are composed of the elements cal- 
 cium, carbon, and oxygen. 
 
 6. Treat a small piece of gypsum with acid, compare 
 it with the action of the acid on marble and limestone. 
 
 7. Break off a small piece of quartz from one of the 
 pebbles found on the lake shore or the banks of a stream, 
 and drop it into the acid ; is there a change? 
 
 8. In the same way try a piece of flint or any other 
 flinty hard stone in your collection ; does the acid affect 
 them ? Test also a piece of slate. 
 
 9. Treat a small piece of clay with acid ; does it dis- 
 solve ? 
 
 10. In the same way try a piece of sandstone ; does it 
 differ in any particular from any of the above ? 
 
 11. These hard stones, insoluble in acid, are called 
 silicious stones. They are composed of the elements 
 oxygen, and silicon. The clay is silicious, but contains 
 some impurities. 
 
 Book for RefereiJce. Humboldt Library : No 6, Town Ge- 
 ology. 
 
Zoology. 
 
 GENERAL OBSERVATIONS. 
 
 1. Keep a sharp lookout during the' month for return- 
 ing birds. It is too early to expect the return of any 
 great numbers, yet some may occasionally be seen. 
 
 2. Have the winter visitors returned northward yet ? 
 
 3. Are there any signs of returning spring through the 
 awakenin-g of animal life ? 
 
 PREHENSION OF FOOD. 
 
 The various ways in which different animals seize their 
 food and convey it to their mouths form interesting sub- 
 jects for study. The wonderful precision of the human 
 arm and hand in these movements is worthy of more 
 than passing attention. When baby begins to help itself 
 at the table, the movements are neither graceful nor ac- 
 curate. In attempting to seize the morsel, the unruly 
 shoulder-muscles, which at an early age are the ones 
 chiefly used in guiding the hand, bring the hand down 
 wide of the mark. After repeated efforts, almost by ac- 
 cident the hand comes within grasping distance, and the 
 fingers, without the slightest effort at individual arrange- 
 ment, close like the claws of a bird. The return move- 
 ment is equally awkward ; the shoulder-joint is stubborn, 
 the. elbow refuses to bend, the wrist fails in its duty, and 
 the chubby fist is sent on an excursion from ear to ear 
 
222 NATURE STUDY. [February 
 
 before the morsel is finally lodged within the anxiously 
 waiting mouth. But, see the result of persistent training. 
 After a little time the shoulder makes just the right 
 swing, the elbow makes exactly the right angle, the wrist 
 gives the hand the proper droop, and by an accurate and 
 definite turn of the hand and arm the fingers are mar- 
 shalled into their appointed positions and the food is 
 carried to the mouth with grace and ease. Absolute 
 freedom and precision of movement are acquired, and 
 the difficulties are mastered so early that, from our own 
 experience, we could not even know that they ever ex- 
 isted. If teachers and parents were to give as much 
 care to muscular training for other movements, such as 
 writing, walking, lifting, etc., as they do to thpse con- 
 cerned in getting food to the mouth, it is hardly too 
 much to .say, that, in the child's life, years of time and 
 tons of effort would be saved. 
 
 1. What animals, besides man, make use of their fore 
 limbs in managing their food ? What animals, that you 
 know of, niake no such use of these limbs ? 
 
 2. Is there an essential difference in the character of 
 the food of these two classes of animals ? 
 
 3. What movements of the squirrel's foreleg are like 
 the arm and hand ? In what respect are the paws unlike 
 the hand? 
 
 4. What is the foot-like character retained by the fore- 
 paws ? Why is this ? 
 
 5. If possible to do so, examine the hand of a mon- 
 key ; in what respect is it more hand-like than the fore- 
 paw of a squirrel ? 
 
 6. What differences between the cat and the dog in the 
 use of their forepaws in food-getting ? 
 
 7. Are the cat's forepaws- more or less hand-like than 
 
February] ZOOLOGY. 223 
 
 those of the squirrel? In what respects? The limbs 
 used in grasping are said to be prehensile. 
 
 8. How do animals without prehensile limbs seize their 
 food? 
 
 9. Does there seem to be any correspondence between 
 the shape of the head and the mode of food prehension ? 
 Notice the contour of the heads of the different animals 
 that make no use of their fore limbs in the prehension of 
 food ; compare them with the heads of those that use 
 their limbs for prehension. 
 
 10. Does the attitude of the body vary with the pre- 
 hensile character of the limbs ? 
 
 11. What parts of the face are concerned in the pre- 
 hension of food ? What parts are most used in taking 
 liquids? In taking solids? 
 
 12. Study and explain the process by which we take a 
 drink? (See Physics for January.) 
 
 13. What organs are concerned in this operation ? 
 
 14. Do the dog and the cat drink in exactly the same 
 way? 
 
 15. How do birds drink ? Why do they throw their 
 heads backward ? 
 
 16. How do the horse, the cow, and the sheep seize 
 their food ? 
 
 17. Why is the tongue of a cat rough? Is the dog's 
 tongue similar? Can you see a reason for what you ob- 
 serve ? Keep in mind the wild state of these animals. 
 
 18. A cow's food differs very much from that of a cat ; 
 yet her tongue is rough and rasp-like ; what reason can 
 you see for this similarity in the two animals ? 
 
 19. Can you account for any differences observed be- 
 tween the cow's tongue and that of a horse? 
 
 , 20. What use does the snake make ofJts tongue? 
 
224 NATURE STUDY. [February 
 
 21. In what way do we use our lips in taking food ? 
 
 22. What animals have you observed that make greater 
 use of their lips' for this purpose ? 
 
 23. Can yoir trace any correspondence between the 
 character of the food and the kinds of lips of different 
 animals ? 
 
 24. Are the teeth employed in the prehension of food ? 
 Compare different animals in this respect, such as the 
 horse, the cow, the sheep, the squirrel, the rabbit, the 
 snake, the dog, and the cat, with yourself. 
 
 25. .-Notice the movements and the work done by the 
 different parts of the mouth in chewing or masticating 
 food. 
 
 26. What appears to be the function of the tongue? 
 Of what tissue is it composed ? Tn how many ways can 
 you change its form ? How many different movements 
 does it have ? 
 
 27. With the finger-tip examine the surface of the 
 teeth. How many teeth have you ? 
 
 28. How many different kinds of teeth can you find 
 in your mouth ? 
 
 29. Compare your teeth as far as possible with the 
 animals mentioned in (24). What variations? 
 
 MASTICATION OF FOOD. 
 
 1. Notice the movements made by the jaws of different 
 animals in masticating their food. What are the move- 
 ments of your own jaw ? Is the movement always in the 
 same direction ? 
 
 2. Is the movement dependent upon the kind of 
 food? 
 
 3. Do the teeth correspond in either arrangement or 
 form with the movement of the jaws ? 
 
February] ZOOLOGY. 225 
 
 4. What organs keep the food between the teeth dur- 
 ing the process of mastication ? 
 
 5. What appears to be the particular function of the 
 tongue? How many movements has it? 
 
 6. What part do the front teeth play in mastication ? 
 How are they adapted to their work ? How many are 
 there that are alike? They are called incisors. 
 
 7. What appears to be the use of the teeth next to the 
 incisors on either side ? In what animals are they promi- 
 nent ? Do you make any such use of yours ? These are* 
 canine teeth. 
 
 8. What use is made of the teeth behind the canine 
 teeth ? How are they adapted to their work ? 
 
 g. In comparing yourself with other animals that differ 
 from you in their food and mode of mastication, do you 
 find corresponding differences in the teeth ? 
 
 10. The two teeth immediately behind the canine teeth 
 are called bicuspids, and the remaining ones are the 
 molars. How many teeth have you in all ? The last 
 molar, or wisdom tooth, is not cut until much later than 
 the rest, usually between the ages of seventeen and 
 twenty-five years. 
 
 11. The parts of a tooth are the crown, which is that 
 portion exposed above the gums ; the root or fang, which 
 is embedded in the jaw ; and the neck, that part beneath 
 the gum, but not in the bony socket. 
 
 12. What teeth are most prominent in the dog and in 
 the cat ? In the squirrel ? Why the difference ? 
 
 13. What is the movement of the jaws when the in- 
 cisors are employed ? The molars ? 
 
 14. Do the cat and the dog have the grinding 
 motion when using their back teeth ? What adapta- 
 tion do you see between the movements of their jaws, 
 
'226 NATURE STUDY. [February 
 
 the character of their teeth, and the kind of food 
 they eat ? 
 
 15. Some of the lower animals show a curious and 
 automatic regularity in the movements of the jaw in masti- 
 cation. The cow in chewing her cud will move her jaw 
 with great regularity from twenty-eight to thirty times 
 before swallowing the mass thus ground up. 
 
 16. What reasons can you see for brushing the teeth ? 
 Should a toothpick be used ? Never use a pin or 
 metallic toothpick of any kind, as it is likely to injure the 
 thin but very hard and brittle layer of enamel which 
 covers the outside of the tooth. Children should be 
 taught to cleanse their teeth regularly after meals as soon 
 as they are able to manage a brush. People usually be- 
 gin to pay serious attention to their teeth only after 
 irreparable mischief has been wrought by neglect. 
 
 INSALIVATION AND SWALLOWING. 
 
 1. What further preparation for swallowing, beside 
 being masticated, does the food undergo ? Where does 
 the moisture in the mouth come from ? 
 
 2. By closing the teeth and drawing the tip of the 
 tongue backward and forward, the fluid called saliva 
 may be noticed collecting under the end of the tongue. 
 This arises from two organs called salivary glands which 
 lie under the tongue, and whose office it is to provide 
 part of the fluid necessary to soften and partially dis- 
 solve and digest a portion of the food while it remains in 
 the mouth. The fluid is conveyed from the glands by 
 two tubes called ducts, one of which opens in each half 
 of the under part of the tongue. These openings may be 
 seen by looking into one's mouth, by means of a good 
 
February] ZOOLOGY. ^2? 
 
 light and a miiTor, by turning the tip of the tongue up- 
 ward. They appear about the size of pin-holes. Near 
 these two, other ducts open which come from similar 
 glands located farther back under the tongue. By 
 drawing the cheeks in between the teeth with a kind of a 
 sucking motion, note the moisture which seems to come 
 from the cheeks. Opposite the second molar teeth a 
 duct opens in each cheek which leads from a gland 
 located about midway betweed the ear and the angle of 
 the lower jaw. These are called the parotid glands ; 
 those farthest back undef the tongue are the sub- 
 maxillary, and those in front, the sublingual glands. 
 
 3. How does the saliva differ from pure water ? What 
 use has it besides that of softening and dissolving the 
 food ? 
 
 4. When the food has been fully prepared for swallow- 
 ing, to what point is it gathered ? It is then called a 
 bolus. 
 
 5. How is the bolus forced back out of the mouth ? 
 Note the position of the jaws during this act. 
 
 6. What part of the swallowing is beyond the control 
 of the will ? 
 
 7. What prevents the food from being crowded up- 
 ward into the nasal passages behind the mouth ? Notice 
 the muscular curtain with the elongated uvula hanging 
 down in the back part of the mouth. How does it help 
 in swallowing ? 
 
 8. On the side of the motith in this region look for 
 almond-shaped bodies called the tonsils. They secrete a 
 slippery substance called mucus. Note also the red 
 pillars of the fauces on the sides of the mouth at the 
 entrance to the throat ; these close in above the food and 
 keep it going downward. 
 
Botany. 
 
 This is the last of the winter months, according to the 
 calendar, at least, and it should not be allowed to pass 
 without giving the pupils opportunity to become familiar 
 with the winter condition of plants. Twigs from differ- 
 ent kinds of trees and of the same tree in different locali- 
 ties should be examined, with a view to ascertaining what 
 per cent, of buds is killed. It should also be noticed 
 whether the twigs themselves all survive alike. Unfor- 
 tunately, in this latitude, a few mild days sometimes come 
 in this month which coax the buds into unseasonable 
 activity. These are then caught by later frosts, and the 
 plant must fall back upon its reserve store. It should 
 be noticed which trees and plants are thus most sensi- 
 tive to the spring-like weather, and what ones are least, 
 or not all affected by it. 
 
 1. Can you find out whether the buds are frozen 
 through and through during the winter ? 
 
 2. What is the location of those buds that have been 
 killed, on theejidsof the branches or near the trunk ? A 
 bud that has been killed may be easily recognized by its 
 being brown or black in the center, while living buds are 
 green. 
 
 3. Have you been able to find any twigs that are 
 killed ? 
 
 4. Can you tell whether the toots have been frozen or 
 not ? 
 
 5. Are the grass-blades killed -in the winter? Are the 
 
 228 
 
February] BOTANV. 229 
 
 roots killed ? Dig up some of the roots and find out the 
 kind which some of the different grasses have. 
 
 6. Can you find any mosses that seem to be alive at 
 this season ? 
 
 7. Look on the different sides of the trunks of trees 
 for the green moss-like covering that sometimes may 
 be seen there. 
 
 8. Examine some pine trees of different kinds ; did 
 they shed any of their leaves in the fall ? 
 
 9. Are the leaves that remain on the trees living ? 
 Can you see any regularity in their arrangement ? 
 
 10. Are the leaves grouped the same way in different 
 kinds of pines ? 
 
 ir. Notice the pitchy substance under the bark ; what 
 is made from it ? 
 
 12. Find out how pitch, turpentine, rosin, and tar are 
 produced. 
 
pb^sics. 
 
 AIR. 
 
 A common and interesting application of the facts Ob- 
 served under this head last month may be found in the 
 so-called suction pump. If a short piece of tubing from 
 about a half to three-quarters of an inch bore can be ob- 
 tained, a model can easily be constructed. The straight- 
 sided Argand lamp chimney makes an excellent tube for 
 this purpose. In this sized tube, the working of the 
 valves may be seen. For these, two corks will be needed ; 
 one tightly fitting the lower end and one passing smoothly 
 into the tube. The latter may be made to fit as desired, 
 by wrapping it with a string. Bore a small hole through 
 the corks, and to the upper surface of each fasten by one 
 edge a thin piece of leather large enough to cover the 
 hole. This may be done by drawing a pin down through 
 it and clinching it on the under side. The piston rod 
 may be made by twisting together two wires, leaving 
 them spread at one end, so that they may be passed 
 through the cork, one on either side of the hole. 
 
 The Pump. 
 
 1. Why are the valves needed in a pump ? 
 
 2. Will the pump work if the lower valve is placed 
 some distance up the stock ? How high above the lower 
 end may this valve be located ? Recall the experiment 
 with the mercury last month to explain this.' 
 
 830 
 
February] PHYSICS. 23 1 
 
 3. What is the use of the piston ? 
 
 4. By what means does the water reach the spout of the 
 pump after it passes through the piston valve ? What 
 kind of a lever is the pump handle ? In the force pump 
 there is no valve in the piston, and the water is forced 
 out by a downward movement of the piston through an 
 opening between it and the lower valve. In the fire en- 
 gine the water is thus forced into an air chamber by two 
 such pumps, and to this the hose is attached. By what 
 means is the water forced through the hose ? 
 
 5. Can you see any advantages in forcing the water 
 out in this way instead of lifting it as in the suction 
 pump ? 
 
 6. What is the advantage of the air chamber ? Recall 
 the various properties of air studied in January; 
 
 7. Where should valves be placed in the force pump 
 of the fire engine ? 
 
 8. Is the flow of water into. the air chamber steady or 
 intermittent ? Compare this with the flow from the 
 nozzle of the hose ; can you account for the difference ? 
 
 The Siphon. 
 
 1. Bend a small glass tube similar to the one used in 
 the January work in Physics (the same one will do) so 
 that the two arms are of unequal length. Place the end 
 of the shorter arm in a bottle of water ; apply the lips 
 to the other end, and by suction start the flow of water 
 through the tube. 
 
 2. Can you give a reason for the continuance of the 
 flow ? 
 
 3. Reverse the ends and start the flow again ; does 
 it continue? 
 
 4. Hold the tube in such a way that the ends shall be 
 
232 NATURE STUDY. [Fel^runry 
 
 at the same level and start the flow ; what is the 
 result ? 
 
 5. What is the force that causes the water to begin 
 flowing through the tube ? 
 
 6. Where is the force applied ? 
 
 7. Try tubes that have arms of different lengths ; 
 with those having the same bore, what determines the 
 rate of flow ? 
 
 8. What is the force applied "which causes the flow to 
 stop when the arms are of the same length ? 
 
 9. Where is this force applied ? What is there to 
 overcome this force when one arm of the tube is longer ? 
 
 10. The siphon in a modified form is much used in 
 pumping water out of leaky boats. A jet of steam is 
 admitted at the elbow and forced out through one of the 
 arms ; by doing this, water may be made to flow out 
 through the short arm. Can you explain why this is so ? 
 Why not use the ordinary. form of the siphon in pumping 
 boats ? 
 
 11. What will determine the greatest len-gth that the 
 short arm may be in the ordinary siphon? 
 
 CAPILLARITY. 
 
 1. Examine closely the surface of water in a partly 
 filled glass ; is it exactly level ? 
 
 2. Dip a small piece of glass into a vessel of water ; 
 note the water in contact with the glass. Color the 
 water with a little red ink. 
 
 3. Hold two small plates of glass together along two, 
 of the edges so that the faces of the glass will be but 
 slightly separated ; notice the water between the pieces 
 of glass. 
 
 4. Cover the surfaces of a piece of glass with grease. 
 
February] PHYSICS. 233 
 
 and hold upright in water ; is the water the same as 
 before at the line of contact ? 
 
 5. Hold a glass tube of small bore, open at the end, 
 upright in a vessel of water ; note the water inside the 
 tube. Try tubes of very largq and very small bore ; 
 what difference between them ? 
 
 6. If mercury can be obtained, repeat the above exper- 
 iments, using it in place of the water. What difference 
 noted ? 
 
 7. When the glass surface is clean in the above exper- 
 iments, does it become wet when immersed ? 
 
 8. Does it become wet when smeared with grease ? 
 What difference noted at the line of contact in the two 
 cases ? 
 
 9. Does the mercury wet the glass ? Does it rise or 
 fall at the point of contact ? 
 
 10. The water is said to rise in the small tubes in the 
 above experiments by capillary attraction. Capillary is 
 from the word capillns, rneaning a hair. It is so named 
 because water fises best in the slender hair-like tubes. 
 
 11. How do the conditions for capillary attraction 
 differ from those which caused water to rise in tubes in 
 previous experiments? 
 
 12. Place one end of a string or strip of cloth in a 
 goblet partly full of water, and allow the other 'end to 
 hang over on the outside. Can you explain what takes 
 place? Is the rising of the water due to capillarity? 
 Study carefully the conditions. 
 
 13. Place the end of a stick , in a vessel of water. Can 
 you explain why it becomes soaked? Why does water 
 in a cask prevent the hoops from becoming loose? 
 
 14. How does the oil or alcohol in a lamp reach the 
 upper end of the wick. 
 
234 NATURE STUDY. [February 
 
 BUOYANCY OF LIQUIDS. 
 
 1. Tie a string to a small stone weighing about half a 
 pound and note carefully the weight as it is suspended 
 from the finger. Lower it into a vessel of water, and 
 note the difference in weight. What reason can you 
 assign for the difference ? 
 
 2. Place an egg in a tumbler or bucket of water ; 
 does it swim or sink ? Does it seem to have lost any 
 weight ? 
 
 3. Fill another tumbler with strong salt water, and 
 pour it slowly into the one containing the egg. Can you 
 account for the change in the position of the egg ? 
 
 4. Half fill a tumbler with water, and then, by means 
 of a tube reaching to the bottom, add brine until the 
 tumbler is full. Drop the egg in cautiously ; does it go 
 to the bottom ? 
 
 5. In what part of the tumbler is the brine ? Why add 
 it by means of a funnel or tube ? 
 
 6. Suspend a small stone beneath one of the scale 
 pans of a balance and by weights in the other pan bal- 
 ance it. Now hold it so that the stone is completely 
 immersed in a vessel of water. 
 
 7. What is the force which causes the opposite scale 
 pan to descend ? How is the force applied ? 
 
 8. How much weight must you add to the scale pan 
 above the stone to make the two sides balance ? 
 
 Each pupil may make a balance which will answer the 
 purpose very well. Use a small stick about eight inches 
 long for the beam. By means of three threads suspend 
 from each end the scale pans. These may be made from 
 a piece of tin two inches square by cutting it in one 
 quarter of an inch at each corner, so that the edges may 
 
February] PHYSICS. ^35 
 
 be turned up. The tin caps of small baking soda cans 
 may be substituted. D'rive pins down tlirough the ends 
 of the beam, and turn them up for hooks from which the 
 pans may be suspended. Drive a pin upward through 
 the middle of the beam by which the balance may be 
 supported. Pass another pin through the bottom of one 
 of the scale pans, and turn it up to form a hook from 
 which the stone may be suspended. Balance the two 
 pans by using fine sand. Small shot may be used for 
 weights. Any druggist will determine the number of 
 these to an ounce for you. 
 
 9. Fill a tumbler brimful of water and arrange it so 
 that the overflow may be caught in another vessel. 
 Suspend a small stone under the scale pan and balance 
 it. Immerse it in the tumbler of water and balance it 
 again. Weigh the overflow of water when the stone is 
 completely immersed. How does the weight of the over- 
 flow correspond with that necessary to balance the scales 
 after the stone is immersed ? Why is the weight obtained 
 for the overflow likely to be somewhat inexact ? Can 
 you see from the experiment what the lifting power of 
 water is ? 
 
 10. The weight of any solid or liquid compared with 
 the same bulk of water is its specific gravity. 
 
 Weigh a stone or other heavy body in the air, and then 
 weigh it in water ; the weight of what volume of water 
 does its loss in the latter case represent ? Recall the 
 experiment performed in (9). 
 
 11. Compare the weight of the body in air with the 
 weight of the volume of water found in (10). This will 
 give its specific gravity. 
 
 12. Since tin is heavy enough to sink in water, why is 
 it that a tin cup will float ? 
 
236 NATURE. STuriY. [February 
 
 13. Will an iron pot float ? If brolcen into fragments, 
 will the pieces float ? 
 
 14. How is it possible to build iron vessels that will 
 bear heavy cargoes ? 
 
 15. If a cup of mercury can be obtained, try to sink 
 different bodies into it, such as stone, iron, etc. Can 
 you explain why they float ? 
 
 16. Weigh a small block of wood ; drop it into a ves- 
 sel brimful of water, so placed that the overflow may be 
 caught and weighed as in (9). By means of a pin stuck 
 into the block, push it down just beneath the surface. 
 
 17. Weigh the overflow and compare with the weight 
 of the block ; by comparing this with the result obtained 
 in (9), can you explain why wood will float and iron or 
 stone will sink ? 
 
 PRESSURE OF LIQUIDS. 
 
 I. Take a tin fruit can, or one sirnilar to it, and in one 
 side make a vertical row of smooth holes an inch apart, 
 each large enough to admit a large-sized knittiiig needle. 
 Fit them with smooth pine plugs. 
 
 ~ 2. Fill the can with water and remove the upper plug ; 
 note the force of the jet and the distance the water is 
 thrown but. 
 
 3. Fill again and remove the second plug. Repeat 
 until the flow has been observed from each opening 
 separately and from all at once. 
 
 4. From which opening is the water thrown farthest ? 
 Upon what does the distance that it is thrown depend ? 
 
 5. Try the experiment again, using cans some of which 
 have larger and others smaller diameter, but of the same 
 height. The holes should be as nearly uniform in every 
 respect as possible. 
 
Febraary] PHYSICS. 237 
 
 6. Repeat the experiment, using cans of different 
 heights ; upon what does the force of the jet depend ? 
 
 7. Is the force of the jet affected by the volume of 
 water in the can ? 
 
 8. What is the force which causes the water to issue 
 in the jet ? In what directions is this force exerted ? 
 
 9. Cut a circular piece of cardboard an inch and a half 
 in diameter ; drop it cautiously on the surface of a goblet 
 of water. Press down upon this" the end of a lamp chim- 
 ney (a small one used for a night lamp will answer) and 
 pusli the cardboard below the surface. 
 
 10. What holds the cardboard against the bottom of 
 the chimney } What must be the direction of the pres- 
 sure ? ' , 
 
 11. Pour water cautiously into the top of the chimney; 
 when does the cardboard fall away from the chimney ? 
 How high is the column of water the pressure of which 
 holds the cardboard in place in the first instance ? 
 
 12. Make a drawing of the vessel with the lamp- 
 chimney and card pushed into it, and show by arrows 
 the direction the lines of pressure must take to support 
 the cardboard against ihe bottom. 
 
 13. Hold a cork so that it is half-way to the bottom of 
 a goblet of water ; what is the height of the column of 
 water that is pressing it downward ? What is the height 
 of the column pressing it upward ? Why does it rise 
 when you let go of it ? (Recall 17 under Buoyancy of 
 Liquids.) 
 
 14. In the same way show why a stone, a piece of lead 
 or iron, must sink ? 
 
 15. Under what conditions would a body remain sus- 
 pended in the midst of a vessel of water ? 
 
 16. When you place your hand at the bottom of a 
 
238 NA TURE STUD Y. [February 
 
 bucket of water, do you notice the weight of the water 
 on top ? Would you feel the weight if the bucket of 
 water were set upon the top of your hand ? How do the 
 conditions in the last two experiments differ ? 
 
 17. Why is it that fishes can live and can swim with 
 ease in the water at great depths ? Why do they become 
 distended when brought to the surface ? 
 
Cbemlstrij. 
 
 CARBON. 
 
 1. Hold a piece of glass or a plate over the flame of a 
 burning candle close to the wick. What collects on the 
 under side ? 
 
 2. Gather a little of the substance formed in (i) and 
 shake well in a bottle or test tube of water ; is it solu- 
 ble ? 
 
 3. Take a small amount of su'gar, half a teaspoonful, 
 and heat it in a shallow dish or spoon. Examine closely 
 the charred mass ; is it sugar ? While the sugar is heat- 
 ing, without burning with a flame, hold a cold glass or 
 porcelain plate over it ; what gathers on the surface ? 
 
 4. What kind of change has taken place ? Is the 
 charred substance soluble ? 
 
 5. Instead of the sugar,use a small piece of meat; 
 what result is obtained ? 
 
 6. Set fire to a piece of wood ; when well ablaze ex-' 
 tinguish, and notice the blackened end. , 
 
 7. Take a small wad of paper, and heat it for some 
 time in a test tube without allowing it to blaze ; what 
 kind of substance remains ? 
 
 8. Coarsely powder a small lump of soft coal and half 
 fill a common clay pipe. Cover the mouth of the bowl 
 with soft clay and place it in the flame of the lamp upon 
 some support, with the stem projecting upward. 
 
240 NATURE STUDY. [February 
 
 9. Watch the end of the stem and from time to time 
 apply a lighted taper. 
 
 10. Can you tell what is produced from the coal within, 
 the pipe bowl ? Note the odor at the end of the 
 stem. 
 
 11. What does the flame remind you of ? 
 
 12. When the flame dies out, remove the lamp and 
 allow the bowl to cool. Then remove the clay and ex- 
 amine the contents. 
 
 13. Has there been a change in the coal ? Compare 
 what you find within the pipe with the coal with which 
 you began. 
 
 14. Has it burned to ashes ? Does it remind you of 
 anything that you have examined in a previous month ? 
 (See Mineralogy for November.) It is in a manner 
 similar to this that coke is manufactured on a large scale. 
 Very large ovens are constructed and are lined with fire- 
 brick. There is one opening in the top through which 
 the oven is charged, and another at the side through 
 which the coke is withdrawn. After the coal has burned 
 for several hours, both openings are closed and the burn- 
 ing is completed without contact with air. The coke is 
 then withdrawn through the opening in the side, and the 
 oven is recharged. The heat of the oven is now suffi- 
 cient to start the burning without resorting to any other 
 means. The country blacksmith makes his own coke 
 usually on the open forge, but it is neither so easily nor 
 so well made as it is in the closed oven. 
 
 15. Where is the great coke-producing region of the 
 United States ? What is coke used for? 
 
 16. As direpted above, heat a pipe half filled with small 
 bits of oak wood ; can you get a flame at the end of the 
 pipe stem ? 
 
February] CHEMISTRY. Ht 
 
 17. How does what remains in the pipe differ from the 
 original wood ? 
 
 "Wood charcoal is made on a large scale by placing 
 sticks of wood in a compact pile which is covered first with 
 a layer of straw and then with earth and turf. Small 
 holes are left at the bottom and also one at the top. 
 Through the latter the pile is ignited, and when the burn- 
 ing is well started the opening at the top is closed, and 
 the pile is allowed to smolder for several days or weeks, 
 according to its size. Finally the holes at the bottom are 
 closed ; after the fire goes out the pile is uncovered, and 
 the wood is found in much the same condition that you 
 found it in the pipe. 
 
 18. Wet a small wad of paper with ammonia and drop 
 it into a clean bottle ; when the odor of ammonia is strong 
 in the bottle, remove the paper and drop in some pow- 
 dered charcoal. Cork and shake for a few minutes and 
 note the odor. Can. you account for the disappearance 
 of the ammonia gas after the bottle has stood for some 
 time ? The charcoal should either be fresh or else heated 
 red-hot and cooled under a glass just before placing in 
 the bottle of ammonia gas. 
 
 ig. Fold a small-sized circle of filter paper and place 
 it in a funnel. Fill it two-thirds full of powdered char- 
 coal. Pour upon this a dilute solution of indigo ; how 
 has it been changed by passing through the charcoal ? 
 Try some vinegar instead of the indigo solution. Small 
 filters ready cut are very cheap, and may be obtained from 
 any druggist. Fold it first in halves, then in quarters, 
 then in eighths. Press the creases with the thumb nail, 
 but avoid touching the filter between them. Open it up and 
 drop the pointed end into the funnel. Pour a gentle stream 
 of water into the filter, and see that it adheres closely to 
 
242 NATURE STUDY. [February 
 
 the inner surface of the funnel. It is then ready for 
 use. 
 
 20. Can you see any reason why charcoal is used in 
 filters and as a disinfectant ? 
 
 21. The charcoal obtained in the foregoing experiments, 
 is, as was learned in Mineralogy for November, carbon. 
 It is not, however, very pure. It is known as one of the 
 chemical elements ; that is, thus far, no one has been able 
 to separate it into simpler parts. Other forms of carbon 
 are the diamond (which is crystallized carbon), soot, lamp- 
 black, coke, animal charcoal, graphite, and mineral coal. 
 The formation of all of these except the diamond, graphite, 
 and coal, is somewhat familiar to us. It will be remem- 
 bered that in January we worked out the history of a fos- 
 sil fern-leaf which was found imbedded in coal. Further 
 search will show that the coal contains traces not only of 
 many ferns, but the remains of large trees and stumps 
 also. In fact the whole coal seam has been shown to be 
 the remains of a vast bed of vegetation that was buried 
 as the fossil fern was, and with it, long ages ago. Under- 
 neath is the layer of clay from which the great forest of 
 plants grew. Beneath the sediment that settled upon it, 
 the vegetable mass was gradually transformed into coal. 
 Where the covering was porous and the gases that were 
 formed escaped, the anthracite was formed ; where the 
 gases were retained bituminous coal was the result. It 
 is interesting to consider to what extent carbon enters 
 into all living things. The story of how it does so, though, 
 must be reserved for a future lesson. 
 
 22. Recall experiment (15) under Chemistry for Decem- 
 ber ; what was the substance in the jar after the charcoal 
 or carbon was burned in it? You will remember that a 
 lighted taper would not then burn in it, although it did 
 
February] CHEMISTRY. , 243 
 
 burn very freely in the gas O, which is another chemical 
 element. 
 
 23. What became of the O when the charcoal was 
 burned in it ? What became of the charcoal or carbon? 
 
 24. Where did the new substance come from ? Was it 
 a solid or a gas ? How did it differ from O ? How did 
 it differ from C (carbon) ? The new substance thus 
 formed by the burning (which was nothing but the two 
 substances forming a union) is carbon dioxide gas (CO,). 
 Recall the experiments in Chemistry for November by 
 which this substance was obtained. The explanation of- 
 its formation then will be given at another time. 
 
nDeteoroIogi?. 
 
 1. Has the temperature increased or diminished since 
 December ? Compare February with January. 
 
 2. Is the temperature increasing or diminishing at 
 present ? 
 
 3. How does the temperature now compare with that 
 of a previous month in which the days were about the 
 same length as those in February ? 
 
 4. Compare the rate of variation in temperature this 
 month with that of December and January ? 
 
 5. What is "the direction of the prevailing wind ? Has 
 it been a cold or a warm one ? 
 
 6. What wind has preceded rain or snow storms ? 
 
 7. Is there any uniformity in the veering of the wind 
 during a storm ? Can you see a reason for this? Con- 
 sult a signal service map ? 
 
 8. How does the character of a rain in this month differ 
 from one in the summer time ? 
 
 9. How does the amount of fogginess compare with that 
 of previous months ? When do they appear, if at all ? 
 
 10. At what temperature has most of the snow fallen ? 
 
 11. Has rain or snow been most frequent this month ? 
 
 12. What winds have been accompanied by a thaw ? 
 
 STUDIES OF SIGNAL SERVICE MAPS. 
 
 13. Can you see any relation in position or as cause 
 and effect between the Low Areas and the place of heavi- 
 est rainfall ? 
 
 244 
 
February] METEOROLOGY. 245 
 
 14. Do the Low Areas lie chiefly in the same region 
 which they occupied in previous months ? 
 
 15. In what quarter of the country have most of the 
 •great storms originated this month ? Compare with last 
 month. 
 
 i6. Which way do the storms travel ? Have there been 
 rain and snow at the same time in different parts of any 
 one storm ? 
 
 17. Is there any uniformity in the direction of the wind 
 in these great storms ? 
 
 18. What is the direction of the winds with respect to 
 the High Area? n 
 
 19. Trace a line through the most southern points 
 touched by the zero isotherm. How does its position 
 compare with that of l^st month ? 
 
 20. In the same way trace the snow line, and compare 
 with January. 
 
astronomy. 
 
 From the almanac it will be learned that Mercury wil' 
 appear as morning star February 6.* This planet is dis- 
 tant from the sun about thirty-five millions of miles (see 
 September), and has a diameter one-third that of the 
 earth. Its time of revolution is about eighty-eight days. 
 
 With objects to represent the sun, Mercury, and the 
 earth, it will be interesting to study the relative position 
 of the three bodies at different times during the year. 
 A diagram on the blackboard should also be used, and 
 the position of the planets Mercury, Venus, and the 
 earth, as seen at this season, should be marked as accu- 
 rately as possible. New figures should be added each 
 month which will show how their positions are changing. 
 
 1. Why is it that Mercury changes from morning to 
 evening star more frequently than Venus ? 
 
 2. Why is it seen as either morning or evening star 
 only for a comparatively short period ? 
 
 3. With Mercury, Venus, and the earth on the same 
 side of the sun, and in a straight line with it, what will 
 be their positions at the end of one month ? At the end 
 of Mercury's year ? 
 
 4. Will Mercury ever be visible at midnight ? 
 
 5. Show what the relative position of the earth, sun, 
 and Mercury is when the latter is evening star. When 
 it is morning star. 
 
 6. Can you find out by studying the rate of motion of 
 
 * True of the year l8gi. 
 246 
 
February] ASTRONOMY. 247 
 
 each planet how often it will be either a morning or 
 an evening star during a year ? 
 
 7. In which of the preceding months did the day's 
 length" correspond to that of this month ? 
 
 8. The length of the noon shadow on the measure at 
 the present time corresponds with what previous month ? 
 
 9. During which of the preceding months did the sun 
 rise and set at about the same points on the horizon that 
 it does now ? 
 
 10. Can you explain why at two different seasons there 
 should be the correspondence noticed in the observations 
 suggested by the last three questions ? Try to show 
 this by using the globe or by blackboard diagrams. 
 
 11. Is the, rate of variation in the day's length increas- 
 ing or diminishing this month? 
 
 12. Compare the day's length at Boston or New York 
 with that at New Orleans ; why should there be the dif- 
 ference noted ? Most almanacs give the length of day 
 at all of these places. 
 
 13. 'Is it the latitude or longitude that affects the day's 
 lejigth ? 
 
 ,14. Is the day increasing in length at both places at 
 the same rate ? Why does the rate differ ? 
 
 15. Is the difference in the rate of variation uniform 
 throughout the month ? 
 
 16. Can you by any observation of the heavenly bodies 
 tell in what direction the earth moves in its orbit ? 
 
 i7._ Note the position of some conspicuous constella- 
 tion, as Orion, at a certain hour, say eight o'clock in the 
 evening. Observe its position during the month, at the 
 same hour ; is it always the same ? Explain. 
 
 18. Constellations. — In addition to those mentioned 
 last month, Leo, Cancer, Canis Minor, and Canis Major 
 may be given. See Clarke's How to Find the Stars. 
 
C5eograpb^. 
 
 EURO-ASIA. RELIEF AND DRAINAGE. 
 
 The structure of this great land mass does not present 
 the same simplicity that is noticeable in the double 
 continent of the New World. By beginning with a 
 consideration of the rivers, their size, and their direction 
 of flow, a fair conception of the principal features of 
 relief may be obtained. The many strong contrasts 
 between the Old World and the New World which are 
 due to the difference in direction and position of the 
 great highlands should be carefully considered. The 
 pupils should in every case work out the problems 
 presented by means o^ map modeling and by use of the 
 best physical maps that can be procured for reference. 
 The study should be accompanied by stories and nar- 
 ratives that will keep the conception of the pupil from 
 being narrowed down to the area of sand in the 
 modeling pan before him. This will not be the. case if 
 sufficient time be taken to work in such pictures of the 
 countries as may be obtained from the many good books 
 of travel of the present time, and from the many excellent 
 magazine articles of a similar kind. Too much haste on 
 the part of the teacher is a common fault with many, and 
 it is a most serious one. The conception of a continent 
 is too vast in its scope to be obtained without long and 
 careful study. 
 
 243 
 
February] GEOGRAPHY. 249 
 
 I.. After modeling the outline of the land mass of 
 Euro-Asia, notice the direction of the chief highland 
 region. What contrast does it present with the cor- 
 responding great highlands of America ? 
 
 2. Note its position in the land mass ; in this respect 
 does it present similarity or contrast with the New World 
 highlands? 
 
 3. What is the direction of the great slope of the con- 
 tinent ? Note the direction of the longest rivers. 
 
 4. What ocean ■ receives the drainage of the greater 
 part of the continent ? Compare this with the New World. 
 
 5. Can you understand why the drainage waters are 
 not gathered into a very few great river systems, as in 
 North and South America ? 
 
 6. On which side of the great highlands are the greater 
 river systems ? Why is it so ? 
 
 7. North of the great highlands, do the rivers indicate 
 any secondary water-partings ? 
 
 8. Contrast the formation of river systems on the 
 opposite sides of the great highlands. To what is the 
 difference due ? 
 
 9. Note the direction of the rivers west of the Ural 
 Mountains ; what does it indicate as to the surface of 
 northeastern Europe ? From what other region do 
 European rivers flow ? 
 
 10. What do the rivers on either side of the Ural 
 Mountains indicate as to the character of this ridge? 
 
 11. From the general direction of the rivers, can you 
 locate the highest region of the great highlands ? 
 
 12. Where are the greatest depressions within the con- 
 tinental outlines ? 
 
 13. Are there any rivers in Asia that do not reach the 
 sea ? Why is this ? 
 
25° NATURE STUDY. [February 
 
 14. In how many directions do the largest Asiatic rivers 
 flow ? How many large rivers in each group ? Note 
 those on the north, the Obi, the Yenisei and the Lena ; 
 on the east the Amoor, the Hoang-ho and the Yang-tse- 
 kiang ; the Mekong and the Irawaddy on the southeast ; 
 the Brahmapootra, the Ganges and the Indus on the 
 south, and the Araoo Daria and Sir Daria flowing into 
 the Aral sea on the west. 
 
 15. Contrast this grouping of the rivers with those of 
 the New World ; what is the cause of the difference ? 
 
 16. What effect does the position of the highlands have 
 upon the development of Asia ? Why is the effect less 
 marked in Europe ? 
 
 17. What effect does the direction of the highlands 
 have upon the development of the continent ? Contrast 
 it in this respect with the American continents. 
 
 18. How does the direction in which the great rivers 
 flow affect their value to man ? 
 
 19. Compare the great plateaus of Euro- Asia with those 
 of the New World, as to their relation to the great 
 mountain system. 
 
 20. Compare the position of the highest mountain peaks 
 of Euro-Asia in the great highlands with these in the 
 great highlands of the Americas. 
 
 Books for Reference. Guyot's Physical Geography. Ritter's 
 Comparative Geography. 
 
Last month an attempt was made to trace the history 
 of a fossil plant. In many places the fossil remains of 
 animals are more abundant, and they are certainly of 
 equal interest. There are few schools in which at least 
 some of the pupils have not found fossil animals, or parts 
 of them, and they may be made available for the whole 
 school. The history of such fossils must be worked out 
 along much the same line as that followed with the plant, 
 but thedifferent environment requires a little modifica- 
 tion of treatment. 
 
 The way in which animal and plant remains become 
 buried beneath the cloud of sediment that is being con- 
 tinually thrown down on the floor of seas and lakes may 
 be illustrated by stirring into a jar of water a quantity of 
 fine mud or sand and then dropping into it bones, shells, 
 water-soaked sticks, leaves, etc. When the silt has set- 
 tled, pour off the water and allow the sediment to be- 
 come a dry cake. Then, by cutting or breaking it, the 
 bones, etc., will be found to be in a ti'ghtly-fitting mold. 
 Most pupils have noticed how sticks, etc., are buried by 
 every little stream in its sand bars and in the mud along 
 its banks.' 
 
 1. Continue the observations made last month as to the 
 depth to which the ground is frozen. Is it frozen to a 
 greater depth than it was then? 
 
 2. If it is possible to visit a quarry or an exposed ledge 
 
252 NATURE STUDY. [February 
 
 of rock, notice whether the frost is causing it to crumble. 
 Can you find any rocks that have been split by freezing ? 
 
 3. Notice the exposed sides of ditches or hillsides ; can 
 you see any effects of freezing ? Does vegetation in- 
 crease or diminish the effects of frost in such places? 
 
 4. Have you ever found, while in the woods or else- 
 where, the remains of animals that have died ? What do 
 you think must become of these after a time ? 
 
 5. What animals have you found thus in a state of de- 
 cay ? What parts were missing ? What parts will last 
 longest ? Have you ever found insects in this condition ? 
 Have you ever found worms or birds ? 
 
 6. Before the neighborhood where you live was settled, 
 do you know what wild animals lived there ? What be- 
 came of their bodies after death ? Have you ever found 
 their bones ? 
 
 7. Do you know of animals that bury their dead ? 
 Think of some of the accidents that might cause an ani- 
 mal to be covered with earth soon after death. Which 
 would-be more favorable, a forest or desert ? 
 
 8. Compare the chances of a land animal with those 
 of one living in the sea for being accidentally buried soon 
 after death ? Which is more likely to be eaten by some 
 other animal ? 
 
 9. Which kind of animal, land or water, is likely to - 
 decay the more rapidly ? Which one has in its body the 
 most material that will tend to resist decay ? What are 
 such parts ? 
 
 10. Have you ever found traces of any kind of the re- 
 mains of an animal ? 
 
 11. What are direct proofs you have that such traces 
 are the marks of a once living animal? 
 
 12. Can you tell whether it was a land or a water ani- 
 
February] GEOLOGY. 253 
 
 mal ? Of which class are the remains most abundant ? 
 Why? 
 
 13. What animal living now does it most resemble ? 
 
 14. If it be the remains of a water animal, can you 
 imagine something as to what its surroundings must have 
 been ? Did it live in sea, lake, or river ? In salt or fresh 
 water ? 
 
 15. Can you tell whether it lived in deep or shallow 
 water ? Was it clear or muddy ? What other evidence 
 is there that water once covered the region where it was 
 found ? 
 
 16. Can you tell what range of temperature the water 
 may have had ? 
 
 17. Did it eat ? If so, what must have been its food ? 
 
 18. Did the animal walk, swim, crawl, or was it fixed? 
 ig. Did it have an inside skeleton or an outside shell ? 
 
 20. What were the soft parts of the body? 
 
 21. Could it see and hear? Do you see anything 
 which would show whether it had a voice or the power of 
 making a noise ? 
 
 22. Can you tell whether there were many more ani- 
 mals like this one that lived at -the same time ? What 
 .way could you prove this ? 
 
 23. Have you any means of knowing how long the ani- 
 mals lived ? Have you any means of knowing how long 
 the water may have covered the region where this ani- 
 mal lived before it was born ? How Would you look for 
 evidence of this kind ? 
 
 24. Can you tell whether it lay very long before it be- 
 came covered ? 
 
 25. By what process do you think it was covered ? 
 
 26. Was it covered gradually or suddenly ? By fine 
 or coarse material ? 
 
2S4 , NATURE STUDY. [February 
 
 27. Do you have in the fossil the real substance of the 
 animal tissues ? 
 
 28. If the animal tissues are not present, can you find 
 any evidence as to whether their decay was slow or 
 rapid ? 
 
 29. How must the stony substance which took the 
 place of the tissues have been deposited there ? Is it 
 likely it was deposited there before the animal was com- 
 pletely buried ? 
 
 30. Is there any way of finding out whether the water 
 remained long in the region where it was buried ? What 
 would the amount of rock and earth above the stratum 
 in which the fossil was found indicate ? 
 
 31. Is there any way by which you could determine 
 whether or not the sea revisited the region where the 
 fossil was found after leaving it the first time ? 
 
 32. Suppose fossil plants were to be found in strata or 
 layers some distance above the stratum where the fossil 
 animal was found ; what chapter in the history of the 
 region would that unlock ? 
 
 33. When the water this last time left the place where 
 the fossil was found, is there any reason to believe that 
 the surface was higher than it is now ? 
 
 34. Can you find any evidence as to why the water left 
 the locality where the fossil was found ? Was the ground 
 uplifted ? 
 
 35. If the ground was uplifted, was the movement slow 
 and gradual or rapid and violent ? 
 
 36. What changes did the soft material in which the 
 remains of the animal were embedded undergo in the 
 coarse of time ? 
 
 37. Was the substance of the rock melted or affected 
 by great heat after the animal was entombed ? 
 
February] GEOLOGV. ii,i, 
 
 38. Can you think of any conditions which surround 
 animal life at present that must have surrounded this 
 fossil animal while living ? 
 
 39. Can you think of any conditions present now which 
 must have been absent at that time ? Which may have 
 been absent ? 
 
 ' 40. If the fossil you have is that of a land animal, can 
 you tell anything of its habits ? Did it likely live on an- 
 imal or vegetable food ? What part of its body that 
 could be preserved, would be the most useful in answer- 
 ,ing this question ? 
 
 41. Was it warmer or cooler than now when it 
 lived ? 
 
 42. In what respects must the history of a laijd fossil 
 differ from that of an animal that lived in the water ? 
 
 43. If animals like those whose fossil remains have 
 been examined do not exist now, can you assign any 
 reason for the race dying out ? 
 
 44. What natural change in conditions can you imagine 
 that might take place, which would tend to cause certain 
 of our living species of animals to die ont gradually, not 
 suddenly ? 
 
 45. What slight change would affect the earthworms ? 
 What would affect birds ? What would affect fishes ? 
 
 46. What artificial causes are removing animals from 
 the earth ? 
 
 47. What classes of animals now living will probably 
 never become fossilized ? Is it possible that such animals 
 may have existed when the fossil you have examined 
 lived ? 
 
 48. Do you think it would be possible for soft animals 
 now living, such as earthworms, to leave any traces of 
 their existence as fossils ? 
 
2S6 NATURE STUDY. [Februaty 
 
 49. From what you have studied about fossils, do you 
 thinlc fossilizatidn of animals and plants is the rule or 
 exception after death ? 
 
 Book for Reference. Humboldt Library : No. 33, Vignettes 
 from Nature, chap. viii. 
 
flDineraloa^. 
 
 Last month certain stones were examined, some of 
 whose properties were learned by means of acids. Some 
 additional facts may be learned this month about these 
 same stones by burning or roasting them in the fire. 
 
 1. Hold a small piece of limestone in the flame of the 
 lamp till red hot clear through. It^may be done by using 
 pincers or by means of a wire wrapped around it. Lay 
 aside till cool and moisten with water ; what change 
 takes place after some little time? The rapidity of the 
 change' depends upon the variety of limestone used. 
 
 2. What is thus formed ? What use is made of the 
 substance thus obtained ? When sand is added and the 
 mixture is wet, the lime and the silica of the sand unite 
 and form a strong cement. 
 
 3. In a similar manner burn a piece of gypsum ; when 
 cool add a little water and allow it to stand a few minutes. 
 What is the nature of the substance found ? Have 3^ou 
 seen it before ? For what is it used ? Why is it called 
 plaster of Paris ? 
 
 4. Make a small model of something of the clay used in 
 January and let it dry pa,rtially. Then burn it thoroughly 
 in the flame of the lamp ; what change is produced ? 
 
 5. In what does the value of clay for manufacturing 
 purposes consist ? What things are made from it ? 
 Where is it found ? Pure clay is white, but various im- 
 purities impart different colors to it when burned. The 
 
 257 
 
258 • NATURE STUDY. [February 
 
 redness of bricks is due to the presence of irpn oxide, a 
 compound of iron and oxygen. 
 
 6. Treat in the same way the silicious stones that 
 were used in January ; compare the results with those 
 obtained above. 
 
 7. Make a full comparison of the two classes of stones 
 examined during January and February. 
 
Zoology. 
 
 This month is, perhaps, the best one of the entire 
 year in which to commence the study of outdoor life. 
 One may now start, as it were, at the very beginning, 
 and for a time, if his wits be sharp, keep pace with the 
 advancing season as it spreads out on every hand. Every 
 bright, warm day, though it be wedged in between wintry 
 ones, is pregnant with hope to all things that live, and 
 the natural interest of the pupils should be properly 
 encouraged. Discouragement, however, is all too easy, 
 and a fruitful source of it is in much of the science read- 
 ing of the schools. A great deal of this is devoted to 
 the so-called " wonders " of nature, and when the pupil 
 fails to see anything of the kind about him, he is apt to 
 conclude that he is either not a good observer or that he 
 is in a poor locality. 
 
 Two things should be kept clearly in mind : first, that 
 what is read in any one book is not the result of one man's 
 observations alone, but, usually, that of very many people 
 whose successive lives have covered, perhaps, hundreds 
 of years ; and second, that the truly wonderful things 
 in nature are rarely the violent ones. Not the flood, the 
 tornado, the lightning, but rather the gentle rain, the soft 
 breeze, and the mild but life-giving sunbeam, have made 
 the earth what it is. 
 
 No one locality presents all of the interesting things 
 that may be studied in nature ; it is equally true that no 
 locality is entirely void of all of them. It may be said, that 
 
26o NATURE STUDY. [March 
 
 every region has some feature that will make it distinct- 
 ively an interesting place of study. To nature's students 
 her treasures are equally divided, and it should be the aim 
 of the teacher to have the pupils become interested in the 
 things at their feet. If they can find nothing there 
 worthy of their study, they will probably fail in their 
 search wherever they go. 
 
 The pupils should be impressed with the necessity of 
 bestowing great care upon the descriptions which they 
 prepare of the things they observe. To do this requires 
 no little skill on the part of the teacher. If a minutely 
 detailed description is insisted upon with beginners, the 
 work becomes tiresonie, because it is really beyond their 
 powers of observation, and it is therefore non-educative. 
 What is meant is merely this : whatever is really seen, 
 and attempted in the description, should be clearly 
 defined. For example, if the color of a bird is gray, it 
 should be stated gray, and not black or brown ; or, if it 
 is said that a bird walks on the ground, it should mean 
 " walk," and not hop. Pupils are usually anjcious to 
 know the names of birds and other animals which they 
 have seen. Even though the teacher may know the 
 name perfectly well from an imperfect description, it 
 should be a rule (to which, of course, there may be judi- 
 cious exceptions), that the pupil must give a description 
 sufficiently accurate to enable any one to recognize it at 
 sight, if he be familiar with the terms used. A pupil who 
 does not have sufficient interest and enterprise to do that 
 much work for the sake of the name he desires, would be 
 very little benefited if it were given him outright. He 
 must feel from the first that he will not be permitted to 
 get something for nothing ; that if he would have a 
 return he must first make an investment. 
 
March] 
 
 ZOOLOGY. 
 
 261 
 
 This month a calendar should be provide4 in which the 
 pupils can record their observations as the season ad- 
 vances. It-should be large enough to admit of the record 
 being made writhout crowding, and the writing should be 
 in a clear, bold hand. As a convenient form, the follow- 
 ing model is suggested. If a frame with glass be pro- 
 vided, with a hinged back, it will be kept cleaner, and 
 will present a neater appearance. In this may be re- 
 corded the times of the return of birds, the first flowers, 
 etc.. 
 
 NATURAL HISTORY CALENDAR. 
 
 189—. 
 
 OBSERVATION. DATE. PLACE. BY WHOM. 
 
 REMARKS. 
 
 GENERAL OBSERVATIONS. 
 
 1. Does animal life, this month, give any indications of 
 returning spring ? 
 
 2. Have you noticed any frogs, toads, or other animals 
 that hibernate during the winter ? Do they show any 
 effects of their long sleep and fast ? 
 
 3. Have any of the birds which rnigrated last spring 
 returned ? Have a,ny of the birds which visit us during 
 the winter disappeared ? 
 
 4. Do the returning birds come in flocks, in pairs, or 
 singly ? Can you tell whether the first ones that come 
 are the young or the old birds ? 
 
262 NATURE STUDY. [March 
 
 5. Do the males or females come first? What do 
 these birds do if overtaken by a cold snap ? 
 
 6. What is the food of the birds that return earliest ? 
 
 7. Do they immediately begin nest-building ? Can 
 you tell whether or not they repair the old nests? 
 
 8. What are the most serious dangers that threaten the 
 birds that first return ? 
 
 9. Do the returning birds seem to be as numerous as 
 those that migrated last fall ? 
 
 10. Have they changed their plumage ? Do the birds 
 sing? 
 
 11. What kinds of insects, if any, are abroad this 
 month ? Study their habits. Where do they live ? 
 
 12. Upon what do they depend for food ? In what 
 way are they adapted to getting it ? 
 
 13. Are they the prey of any other animals ? Upon 
 what do they rely for safety, defense, concealment, or 
 flight ? 
 
 14. Examine some of the cocoons that were spun last 
 fall, and may now be easily seen upon twigs of trees and 
 bushes ; are there any signs of life about them ? 
 
 15. Observe some of the ant-hills, or other haunts of 
 ants, that were noticed last fall ; are there any signs of 
 activity? 
 
 16. Have you seen any of the work of earthworms 
 this spring ? Can you find any near the surface ? 
 
 THE CIRCULATION. 
 
 1. Place two fingers of the left hand over the region 
 of the pulse, in the wrist of the right arm, and count 
 the pulsations. Take the average per minute for five 
 minutes. 
 
 2. Place the fingers in the region of the temples, a lit- 
 
March] ZOOLOGY. • 263 
 
 tie in front of and above the ear, and count the pulsa- 
 tions felt there. Compare with the number felt in the 
 wrist. 
 
 3. Rise, and count again in a standing position. 
 
 4. Take vigorous exercise of some kind for a minute, 
 and count again. Place the fingers about the middle of 
 the chest, a little to the left of the breast-bone ; can you 
 notice pulsations there ? 
 
 5. Do you notice any correspondence between the pul- 
 sations of the chest and the wrist ? Between those of 
 the wrist, temples, and chest ? 
 
 6. When were the pulsations slowest ? When most 
 rapid ? 
 
 7. Does the number of respirations increase with vig- 
 orous exercise ? 
 
 8. The pulsations felt in the chest are due to the al- 
 ternate contraction and expansion of the heart. Each 
 contraction forces a quantity of blood out into a set of 
 slightly elastic tubes called arteries. These are dis- 
 tended each time they receive the blood, and in conse- 
 quence a pulsation is felt wherever the artery lies near the 
 surface. 
 
 9. Cross the legs so that one knee rests over the 
 other ; notice the toe of the ,foot uppermost ; can you 
 explain why it cannot be held perfectly still ? 
 
 10. From your own observations, can you tell how 
 exercise affects the blood-flow ? 
 
 11. What effect has violent exercise upon the appear- 
 ance of one's face ? Can you explain this ? 
 
 After passing through the arteries, the blood enters a 
 dense network of very minute tubes called capillaries. 
 While the blood passes through the capillaries, important 
 transfers take place. The nutriment, digested in the 
 
2^4 NAl'URE STUDY. [March 
 
 alimentary canal, and received into the circulation by 
 the capillaries and other absorbent vessels which lie in 
 its walls, now passes out to renew the tissues by soaking 
 through the walls of these minute vessels. At the same 
 time, waste materials, dissolved in the fluids which bathe 
 the tissues, soak through the walls into the blood, and 
 are carried to the organs of excretion — the lungs, kid- 
 neys, and skin. How do we know that the blood circu- 
 lates ? This is by no means an easy question, or it 
 would not have taken so many centuries for wise 
 men to find out the fact. Two hundred and ,fifty 
 years ago it was not only unknown, but the idea was 
 ridiculed. 
 
 12. Note the blue veins lying just under the skin ; 
 have you any proof that blood is flowing through them ? 
 Which direction ? ' 
 
 13. Hold the hand loosely downward and shake it 
 gently ; how do the veins change in appearance ? 
 
 14. Hold the hands above the head, and shake them in 
 the same way ; what difference is noticed ? 
 
 15. While holding the hands downward as in (12), 
 press with a finger on a vein, and slip it toward the fin- 
 gers ; note carefully the appearance where the veins fork. 
 Small pocket-like valves are placed here to prevent a 
 backward flow of blood. Can you tell in which direction 
 they prevent the blood flow ? 
 
 t6. From the capillaries (see 10) the blood passes 
 through the veins to the right half of the heart, and 
 thence to the lungs, where it enters the capillaries of 
 these organs. (See Respiration.) From the lungs, the 
 blood returns to the heart, the left half, and is forced out 
 into the arteries again, which carry it to the system. 
 
 17. Wrap a string tightly around a finger about an 
 
March] ZOOLOGY. 265 
 
 inch from the end ; can you tell why it swells up and 
 changes color ? 
 
 18. With a pin, or needle, make a slight prick through 
 the skin, and draw a large drop of blood. This opera- 
 tion is not painful in the least. 
 
 19. Is the blood perfectly fluid ? 
 
 20. Do not disturb it for some time, but closely ob- 
 serve any changes that may take place. 
 
 21. Note the clot that forms; does the entire drop 
 become solid ? 
 
 22. The matter that becomes solid in the clot is 
 C3.\\e.A fibrin ; the part that remains \\qyi'\d is VaS serum. 
 How does the serum differ in appearance from the 
 blood ? 
 
 23. If the drop is large enough, transfer the clot to a. 
 clean piece of glass, and move it about with a pin in a 
 httle clean water; does any of it wash away? In this 
 way the solid fibrin maybe separated, from the red color- 
 ing bodies of the blood called corpuscles. 
 
 24. A large quantity of fibrin may be easily obtained 
 thus : Catch a basin of blood in a butcher shop from 
 a freshly killed animal, and with a bundle of twigs or 
 wires whip it vigorously for a few minutes. The fibrin 
 will collect in a stringy mass on the sticks from which it 
 must be removed, and then thoroughly washed until 
 freed from the red corpuscles. This may then be pre- 
 served indefinitely in alcohol for class use. 
 
 25. Is the clotting of blood of any importance to ani- 
 mals ? 
 
 26. What effect does a brisk rubbing of the surface of 
 the body have upon the circulation ? 
 
 27. How does a hot bath affect the circulation .^ How 
 does cold water affect it ? 
 
266 NATURE STUDY. [March 
 
 28. In case of headache from over-study, which would 
 be more apt to afford relief, a hot or a cold foot-bath ? 
 Why? 
 
 29. Why will cold water sometimes relieve a headache, 
 and at other times hot water ? 
 
 30. What animals can you name that you are sure have 
 red blood ? Do you know of any without it ? 
 
 31. Examine the pulse of a young child, and also that 
 of an old person ; what differences do you notice ? Com- 
 pare with your own. 
 
 32. Compare your own pulse with that of your friend's, 
 of about the same age ; note both the rapidity and 
 strength of the beat. At first you may not be able to 
 detect any difference, but a practiced physician would 
 probably find no two exactly alike. 
 
 33. Place the ear near the body of a dog ; can you 
 locate the heart ? Does the rate of beating depend upon 
 the size of the aninjal ? 
 
 34. In the same way examine a cat, a horse, a cow, or 
 any other animal you may have opportunity to observe. 
 
 The time has come when every teg.cher must make a 
 demand upon his school board for a microscope for his 
 school. No similar outlay will give the teacher such a 
 vast increase in power to interest and instruct his pupils. 
 Its use, within the past few years, has revolutionized our 
 notions concerning the nature of most, if not all dis- 
 eases, and it has done more to place the practice of 
 medicine upon a scientific basis than anything else since 
 the demonstrations of Harvey. Without its use it is 
 absolutely impossible for the pupils to get any but the 
 most vague conceptions of the extreme delicacy of those 
 parts of the body that are concerned directly in the vital 
 processes, and consequently need the greatest care. 
 
March] ZOOLOGY. 267 
 
 Believing, therefore, that before the usefulness of this 
 book is outlived, very many teachers will have one at 
 their command, the following directions for showing the 
 circulation of the blood are given. The manipulation of 
 the microscope for school purposes can be learned in ten 
 minutes from a book that is generally sent frith the out- 
 fit, and no teacher should hesitate because he has had 
 no previous instruction. 
 
 (a) Procure a small tadpole, and place it under a wet 
 cloth on a strip of glass. Allow the end of its tail to pro- 
 ject, and cover it with another thin piece of glass. Keep 
 moist, and examine with an inch, three-quarter, or a half- 
 inch objective. This observation is of historic interest. 
 About two hundred and twenty-five years ago, by this 
 means, the circulation of the blood became a demon- 
 strated fact. This occurred ten years after Harvey's 
 death. 
 
 (h) Procure a small water-newt (lizards the children 
 will call them), having external fringe-like g-ills near the 
 mouth. Place in a watch-glass of water, and, as he lies 
 still, watch the pulsating currents through the looped 
 vessels in the gills. It is indescribably beautiful. A 
 very young tadpole will do as well for the purpose. 
 
 (c) Allow a hen to sit upon some eggs for four or five 
 days. Perforate with a pin the large end of one of them. 
 Break away the shell from the upper side, making a hole 
 as large as possible without disturbing the contents. 
 Remove the membrane and examine the delicate net- 
 work of blood vessels that is exposed. Use direct light 
 from above. Look_for the pulsating heart. It is safe to 
 leave the description of this beautiful sight to the ob- 
 server. 
 
 {d) Procure a live frog and wrap it in a wet cloth, ex- 
 
26S Mature study. [March 
 
 posing one hind foot. Tie it to a thin strip of wood 
 three inches wide. By means of thread tied to the toes, 
 spread them so that the web will be somewhat stretched, 
 and then fasten it over a hole in the board, that the 
 light may be reflected upward through it from a mirror. 
 Keep moist. This is a little more difficult to manage 
 than those given above. 
 
 [e) In the instances above given the blood will appear 
 colored. Procure a small spider with semi-transparent 
 legs. Confine it lightly between two glass slips. You 
 will be able to follow a single corpuscle clear down his 
 leg to his "toes" and back again. It looks like a pebble 
 being rolled and pitched along by a current. Can you 
 detect color in the blood ? 
 
 (/) A little later in the spring procure a very young 
 crawfish. You can hardly fail to find a mother " craw " 
 with hundreds of the little fellows clinging to her swim- 
 merets. Coiffine him very carefully as directed above, 
 and examine. You can see the corpuscles chasing each 
 other all through the body, legs, and antennae or feelers. 
 A, marvelous thing to behold ! 
 
 Reference. Humboldt Library : No. 48, Life in Nature. 
 
Botany. 
 
 During this month the pupils should be alert for the 
 first evidences of spring that appear in plants. If the 
 observations indicated in the previous months have been 
 made, they will be ready to notice the earliest changes 
 that occur. The character and tendency of the lessons 
 should be to lead the pupils in the end to a thoughtful 
 consideration of nature's great miracle wrought in this 
 spring-time renewal of life. The opening of a bud is a 
 matter of common observation, and yet it cannot be said 
 to be a simple or commonplace thing. It is the result of 
 causes both near and remote, many of which are apt to 
 escape unnoticed. The opening of the buds and the 
 sprouting seeds that may soon be seen are a verification 
 anew of every law in nature's code. The persistence for 
 ages of certain plants, cultivated and wild, in different 
 latitudes, furnishes strong proof of the uniformity of 
 these laws in their operation. The distribution of the 
 viiie, olive and fig, for example, in Europe, would indicate 
 that the climate has remained almost absolutely un- 
 changed for a great length of time. It is said that a 
 change of one-half of a degree in the mean annual tem- 
 perature would seriously affect the growth of these 
 plants, and render their cultivation difficult, perhaps im- 
 possible, in regions where they now flourish. There 
 could hardly be a finer illustration, either of the sensi- 
 tiveness of the plants to their environment, or of the 
 269 
 
ayo KArChi: ^TUDV. [March 
 
 marvelous balance among those conditions which com- 
 pose it. 
 
 The observations made on the waking plant should be 
 accurate and systematic, within the capacity of the pupils, 
 and a record of the changes ought to be kept. Each 
 pupil should be required to select a tree conveniently lo- 
 cated for daily study. - In connection with this, a study 
 of the wood, bark, mode of branching, etc., may be pur- 
 sued before the buds are far enough advanced to require 
 much attention. 
 
 1. Make a drawing of tlie tree selected for study, 
 being careful to, have the different parts in proper pro- 
 portion. 
 
 2. Is the general figure of the tree symmetrical, as you 
 view it from all sides ? 
 
 3. Can you notice any difference between the north 
 and the south sides ? Between the east and the west 
 sides? 
 
 4. Do trees that grow in the woods modify or change 
 each other in shape ? 
 
 5. Can you tell what deterrpines the height above 
 ground at which a tree begins to branch ? Compare 
 trees that are isolated with those of the same kind in 
 forests. 
 
 6. What variation do you notice in the shapes of the 
 tops of different trees ? 
 
 7. What seems to determine the shape of the top? 
 Compare the shape of a pine tree with that of an apple 
 tree ; all stems like the former are called excurrent, and 
 all like the latter are deliquescent. Excurrent means, lit- 
 erally, running out ; deliquescent means melting or dis- 
 solving ; can you see the force of these meanings when 
 the terms are applied to tree tops ? 
 
March] BOTANY. 271 
 
 8. .What peculiarities of growth give rise to these two 
 forms of tree-tops ? 
 
 9. Woody plants fifteen or twenty feet in height, or 
 under, are called shrubs ; above this height, trees. Will 
 all shrubs become trees if allowed to grow ? 
 
 10. Can you by examination determine the extent to 
 which the roots of a tree spread ? Compare with the 
 spread of the top. 
 
 11. The main stem or trunk of a tree, and the root 
 growing straight downward, are sometimes called the 
 axis of the plant. The stem is the ascending, and the 
 roots the descending axis. Is there a clearly marked 
 plane of division between the ascending and descending 
 parts ? 
 
 12. Procure a piece of a branch two or three inches in 
 diameter, and make a study of the wood. Can you tell 
 in what part of the branch the oldest wood is to be 
 found ? When is the new wood added ? 
 
 13. Make two drawings, one of a cross, and the other 
 of a longitudinal section. 
 
 14. The wood may usually be distinguished as heart- 
 wood, or duramen; and sap-wood, or alburmini. Can you 
 distinguish the two kinds in )'our specimen? What are 
 the differences between them ? 
 
 15. What causes the circular markings that may be 
 seen in a cross section? Are they alike on all sides of 
 the branch ? What will affect the thickness of the rings? 
 Compare the upper and lower halves of a branch. The 
 north and south sides of the stump of a tree. Which 
 ring was formed last ? Notice the soft spongy sub- 
 stance in the center of the twig called pith ; what 
 is the shape of a cross section of the pith-tube? 
 How does it differ from the wood ? Split a twig care- 
 
272 NATURE STUDY. [March 
 
 fully out to the terminal bud ; does the pith reach 
 the bud? 
 
 i6. Notice any radial markings that may be seen in a 
 twig ; does any one cross more than one ring ? Are they 
 found in the bark ? These lines are called medullary 
 rays. 
 
 17. Split the twig, and try to discover the structure of 
 the medullary rays. Compare the wood found in the 
 rays with that about them. 
 
 18. Can you see these rays ia any of the articles of 
 furniture about you? How must the wood be cut to 
 show them to advantage ? How do painters imitate their 
 appearance ? 
 
 19. Can you see any pores in the wood ? Wet one end 
 of a dry piece, and try to blow through it from the other ; 
 is there any evidence that the air passes through ? Are 
 the pores openings into continuous tubes ? 
 
 20. Compare the bark on the trunk of the tree with 
 that found on the twigs ; are there the same layers in 
 both ? What happens if the bark be removed down to 
 the wood ? 
 
 21. How does the bark differ from the wood ? How 
 is it joined to it ? Is there a distinct division between 
 them ? 
 
 22. On the twigs, the layers usually found are the cor- 
 tex, or cortical layer, which is the dark outer covering ; 
 the green layer immediately under it, and the liber next 
 the wood. Are these all present in the older twigs and 
 in the tree trunk ? Find out why the name liber is given 
 to one layer ? What use is made of the cortical layer in 
 some trees ? 
 
 23. The specks often to be found in the bark of twigs 
 
March] BOTANY. ^73 
 
 are called lenticels ; how are they formed ? Is their ar- 
 rangement regular? 
 
 24. Make a careful -examination of the entire tree this 
 month, and be ready to note the first changes that occur 
 in the spring. 
 
pbipsics. 
 
 LIGHT. 
 
 In beginning the study of light, it is of first import- 
 ance that an extended series of simple experiments be 
 devised which will clearly illustrate the fundamental 
 principles of the subject. The observations and experi- 
 ments may be made in such a way as to arouse the deep- 
 est interest on the part of the pupil, and the best thought 
 of which he is capable. The principles underlying the. 
 subject are comparatively few, and may be stated in the 
 simplest language ; but their application is so varied and 
 far-reaching that nothing but a great abundance of simple 
 illustrative experiments in the beginning will ever make 
 them clear. Teachers, here, if anywhere, are apt to make 
 the fatal mistake of supposing that a glib statement of a 
 principle implies mental possession of the concept it 
 embodies. Space will not admit of a sufficient number 
 of observations and experiments being described, in this 
 connection, to make the subject clear ; but such bave 
 been selected as, it is believed, will best indicate to the 
 teacher the kind of work that should be done. 
 
 The apparatus needed is simple, cheap, and easily ob- 
 tained. It is necessary to darken the room for some of 
 the observations, and the teacher should be able to do 
 this quickly. If the windows are provided with solid 
 shutters, there is no difficulty ; but if there be slats in 
 
 274 
 
March] PHYSICS. 275 
 
 the shutters, the end can be attained by tackhig over 
 -them light-proof paper of some kind. A small hole, half 
 the diameter of a lead pencil, in an east, south, or west 
 window, will admit a beam of sunlight that can be util- 
 ized in' a variety of interesting ways. Where there are 
 no shutters, curtains may be substituted with but little 
 trouble. A small looking-glass and a lamp reflector, 
 that may be obtained at any lamp store at small cost, 
 will be needed in a study of reflection. For a lens, the 
 magnifying glass used in botanical work will answer. 
 Directions were given in the September work for making 
 a suitable prism. 
 
 1. Why is it (without considering the eye) we can see 
 an object, such as a book, in the room in daylight, but 
 cannot see it in the darkness at night? 
 
 2. Why is it that we can see it after dark, if a lighted 
 lamp is brought into the room ? In seeing the book, 
 does the light first pass from the lamp to the eye and 
 then to the object, or first to the book and then to the 
 eye ? 
 
 3. Hide the lamp from sight, but place it so that its 
 light falls upon the book ; is the book visible ? 
 
 4. With the lamp in the same position, hold a thick 
 piece of paper between the eyes and the book ; is it still 
 visible ? 
 
 5. What two things are necessary to enable us to see 
 the book ? 
 
 6. Why is it that we can see a lighted lamp when if is 
 brought into a dark room, but cannot see a book, chair, 
 etc. ? The lamp is said to be luminous and the book is 
 non-luminous. 
 
 7. Give all the examples you can of each kind of body. 
 
 8. How can you make a non-luminous body be- 
 
276 NATURE STUDY. [March 
 
 come luminous ? How can you make it non-luminous 
 again ? 
 
 9. Heat a wire red-hot in a darkened room, using your 
 alcohol lamp ; can you see it from all sides? Why ? 
 
 10. Take three pieces of cardboard six inches square. 
 Place one on top of the other and cut a very small hole 
 through all of them ; place these upright several inches 
 apart. Opposite the hole in one of the cardboards place 
 a lighted candle ; can you so place the other two pieces 
 that the light will shine through the holes in all three ? 
 If so, what do you notice about the three holes with 
 respect to each other ? 
 
 11. Wlxy is it the light will shine through all three 
 only when they are in a certain position ? 
 
 12. Arrange a lamp and book as in (3) and try to see 
 the book by looking through the holes in the three 
 cards ; what do you notice about the position of the 
 holes when the book becomes visible ? What do these 
 experiments show you about the lines or rays of light? 
 
 13. Where does the light come from. in (3) whicli 
 makes the book visible ? Describe the path, it must take 
 from the lamp to the eye. In the same way, in daylight, 
 describe the paths of the rays of light which make the 
 different objects about you visible. 
 
 14. Instead of the book used in (3), place a small 
 looking-gla.ss, and, if a sunbeam can be substituted for 
 the lamp, it will be better. What difference, do you 
 notice in the visibility of the two objects ? 
 
 15. Can you see both the book and the glass equally 
 well from all positions ? 
 
 16. Explain why there is a difference in the visibility 
 of the two objects. What difference do you notice in 
 their surfaces ? 
 
March] PHYSICS. 277 
 
 17. The light from the book is said to be diffusedX\%'a\.^ 
 and that from the looking-glass is reflected. By which 
 kind of light do you see most of the objects about you ? 
 What is essential to a good reflector ? Good reflectors 
 are called mirrors. A mirror with a flat surface is called 
 Biplane mirror. 
 
 18. When rays of light strike a mirror, what happens 
 to them ? The rays, from the object to the mirror are 
 ca.\\eA incident rays, and those from the mirror are called 
 reflected rays. 
 
 ig. Conceal the book as in (3) from the eye, but place 
 it so that rays of light will pass from it to a mirror : 
 can you so place yourself with respect to the mirror that 
 the figure of the book will appear ? Do you really see 
 the book ? How can you prove that you do or do not 
 see it ? 
 
 20. Explain how the mirror brings the appearance of the 
 book into view. To do -this, recall (3), (4), and (5) re- 
 lating to the visibility of an object. When is the object 
 itself visible ? The appearance of an object as seen in a 
 mirror is called its image. 
 
 21. Which rays determine the direction in which the 
 image is seen, the incident, or reflected rays ? 
 
 22. Allow a small beam of light to fall upon a mirror 
 arid be reflected ; make the beam more distinctly visible 
 by striking two black-board erasers together near it. 
 Erect a perpendicular line, called a normal, to the sur- 
 face of the mirror at the point of reflection ; note the two 
 angles thus formed. The one between the normal and 
 the incident beam is the angle of incidence ; between 
 normal and the reflected beam, the angle of reflection- 
 Compare these two angles. 
 
 23. Support horizontally a light straight stick about 
 
2 78 NATURE STUDY. [March 
 
 two feet long on its ends eight or ten inches from the 
 floor or table. From its middle point suspend a plumb 
 line. A bullet partly split and thgn closed upon a small 
 thread will do for this. Fill a goblet or pan with water 
 blackened with ink, and place it under the line so that the 
 weight will be below its surface. In the side and near 
 one end of the stick, drive -a tack or small nail, and 
 standing at the other end, place the eye in such a position 
 that its image will appear where the string touches the 
 water. Compare the distance the eye is from the point 
 where the plumb line is attached to the stick with the dis- 
 tance the tack is from it. Make a drawing of the ap- 
 paratus, showing by a line the course of the incident ray 
 from the tack, and the reflected ray to the eye. Point 
 out the angles of incidence and reflection. What does 
 this experiment show as to their relative size ? 
 
 24. Can you see any reason why an image should appear 
 to be behind the mirror ? Can you by drawing a figure 
 representing a mirror, an object, its image, and lines 
 representing the rays of light, show how far behind the 
 mirror the image must appear ? 
 
 25.. Is the image seen by means of the mirror a real 
 one, /. 'e., does it really exist behind the mirror ? Such 
 an image is called a virtual image. 
 
 26. Hold a printed page before a mirror ; explain why 
 the letters appear changed. . 
 
 27. Can you explain why a surface which diffuses 
 light does not give us images of objects ? 
 
 28. Allow a beam of light to strike a concave mirror ; 
 what peculiarity do you notice about the reflected rays ? 
 Explain why they form a cone of light, by using what was 
 learned in (22) and X^s)- The point at which the rays 
 meet is called the principal focus of the mirror. Meas- 
 
March] PHYSICS. 279 
 
 lire its distance from the middle point of the mirror. 
 The middle point of the mirror is called the center of the 
 mirror. 
 
 29. In constructing & normal [set 22) to the surface, 
 notice its relation to the sphere of which the mirror forms 
 a part. Where in the sphere do all the normals meet ? 
 This point is called the center of curvatiire. A line 
 drawn through the center of curvature to the center of 
 the mirror is the principal axis ; all other lines through 
 the center of curvature to the mirror are secondary axes. 
 
 30. Darken the room and hold a small lighted candle 
 close to a concave mirror ; what are the points of differ- 
 ence between its image here and the one it forms in- a 
 plane mirror ? In what respects are the two images 
 alike ? 
 
 31. Move the candle back from the mirror until it is 
 between the principal focus and the center of curvature. 
 Hold a sheet of paper, for a screen, back of the candle ; 
 carefully compare the image here produced with the one 
 seen in (30). 
 
 32. Make a diagram of the mirror and the candle. 
 Draw two or more lines, representing rays of light, from 
 the tip of the flame to the mirror ; show what will be- 
 come of those rays when reflected. Recall what was 
 learned in (23). At what place in the reflected rays do. 
 you find the image ? This point is called the conjugate 
 focus. 
 
 33. The image formed in (32) is called a real image ; 
 how does it differ from a virtual image ? See (25). 
 
 34. Move the candle away from the mirror ; what be- 
 comes of the image on the screen ? As the candle is 
 farther removed, where does the image next appear ? Is 
 it a real or a virtual image ? 
 
28o NATURE STUDY. [March 
 
 35. Again diagram, as in (32), and find where the re- 
 flected rays from the candle meet ; at what place along 
 the reflected rays do you find the image? Explain why 
 the image is inverted here, and why upright in (30). 
 
 36. Notice where the candle is, with respect to the 
 center of curvature and principal focus, when.the image 
 appears on opposite sides of it ; that is, between the 
 candle and mirror, and beyond the candle. Try to ex- 
 plain why you can see a real image in either place. 
 Recall what was learned in (3), (4), and (5). Do not 
 confuse what is riecessary to see an image with what is 
 necessary to form one. 
 
 ■37. Show by a diagram why the size of the image 
 varies with the position of the object. 
 
 38. Hold the candle before the convex surface of the 
 reflector ; in what respects is the image the same as that 
 formed by a plane mirror ? In what respects is it dif- 
 ferent ? 
 
 39. Explain the formation of the image in the convex 
 mirror by diagrams, keeping constantly in mind the laws 
 by which those formed by plane and concave mirrors 
 were explained. 
 
 40. It will be interesting to illustrate how light varies 
 in intensity with the distance from its source. Make 
 from cardboard three screens, one six inches square, 
 one a foot square, ■and one eighteen inches square 
 Draw lines across the last two, dividing them into areas 
 each six inches square. Fasten each screen in an upright 
 a few inches in height. This may be made by splitting a 
 stick, into which the card may be slipped and fastened 
 with a tack. A small block will answer for a base. 
 
 41. Place the smallest card three feet from the flame ; 
 how far from the flame must the second in size be placed 
 
March] PHYSICS. 281 
 
 to be exactly covered by the shadow of the first ? At 
 what distance from the flame must the largest be placed 
 to be exactly covered by the shadow of the second ? 
 
 42. With the th'ree cards in these positions, what do 
 you notice as to the amount of light that each would re- 
 ceive from the flame ? How much would each six-inch 
 square on the second and third screen receive, as com- 
 pared with that received by the smallest card ? 
 
 43. How would the intensity vary at the points occu- 
 pied by the second and third cards, as compared with 
 that occupied by the first ? 
 
 44. Does the edge of the card make a clear-cut shadow 
 at its margin ? Hold a pencil between a light and a 
 screen ; how does the edge of the shadow change as it is 
 moved toward or away from the screen ? 
 
 45. If -possible, use a flat flame, and examine the 
 shadows cast by the edges and by its flat surface. Make 
 a diagram, drawing lines from the different parts of the 
 flame to different parts of the object, and to the shadow 
 beyond,; can you account for the peculiarities noticed in 
 the shadow ? 
 
 46. The'dark central part 'of the shadow is called the 
 umbra J the light border is called \.he. petiumbra. 
 
 47. Can you explain the difference that may be noticed 
 between the shadow of an object cast in the moonlight and 
 that from one illuminated by electric light ? 
 
 Reference. Humboldt Library ; No, 37, Six Lectures on Light. 
 
(Ebemistri?. 
 
 NITROGEN. 
 
 Nitrogen is less interesting than any of the gases that 
 have been examined. On account of its abundance in 
 the atmosphere and the important function it performs, 
 however, it is thought best to make some study of it. 
 The pupils should very early be taught about the- con- 
 stituents of air, and should know the chief properties of 
 each ; also, as far as possible, by simple experiment, they 
 should be taught about the origin, the cause of variation, 
 and the effects of each upon themselves and other living 
 things. 
 
 1. Nitrogen may be made in several ways, none of which 
 are very suitable to be performed by youngchildren. Two 
 methods will be given, which are perfectly safe and pre- 
 sent but few difficulties. The most instructive way is as 
 follows : Take a piece of phosphorus half the size of a 
 pea, and dry it with blotting paper. Place it in a small 
 cup or upon a bit of porcelain, which may be floated 
 upon a small block of wood in a pan of water. Ignite it, 
 and immediately place over it an empty glass fruit jar. 
 When the burning has ceased, allow the white fumes to 
 clear away, and then invert the vessel, without allowing 
 the water to escape, as directed in the experiments with 
 oxygen. 
 
 2. The second method is to take two _parts of bichro- 
 
March] CHEMISTRY. 283 
 
 mate of potash (about one ounce) and ammonium chlo- 
 ride one part. Grind the two together until fine and 
 well mixed. Heat in a flask arranged as directed in the 
 experiment with oxygen, and collect in a jar over water. 
 By the latter method the gas may be generated in a flask, 
 and a test-tube full may be caught by each pupil as it 
 forms. -The cost of the material in either case need not 
 be more than fifteen or twenty cents, to supply fifty 
 pupils with two or three test-tubes of the gas. 
 
 3. Why does the phosphorus continue to burn after the 
 jar has been inverted over it in (i) ? 
 
 4. What does the rising of the water in the vessel, as 
 the burning ceases, indicate ? 
 
 5. Light a long splinter and thrust it into the jar of 
 gas ; each pupil may do this with his test-tube. The gas 
 may be kept until wanted by holding the thumb over its 
 mouth. 
 
 6. What is the effect upon the blaze ? What other gas 
 with which you have experimented has the same effect ? 
 
 7. Into another and perfectly clean test-tube full of 
 the gas, pour a little lime-water; does it undergo any 
 change ? What gas causes lime-water to become milky ? 
 
 8. The gas formed in the above experiments is nitro- 
 gen ; compare it with the other gases that you have 
 made in previous experiments. 
 
 "9. When the phosphorus burned in the air in the jar, 
 the oxygen combined with it and phosphoric acid was 
 formed, which was then dissolved in the water, leaving 
 the nitrogen in the jar ; why could we not get pure nitro- 
 gen by burning a candle in the jar instead of phosphorus ? 
 10. Note the amount of water in the jar after the phos- 
 phorus stopped burning ; how does it compare in bulk 
 with the gas above it I 
 
284 NATURE STUDY. [March 
 
 11. What gas did the water, in rising, take the place 
 of? 
 
 12. The air is a mixture consisting of one-fifth oxygen 
 and four-fifths nitrogen ; what would happen if it were 
 pure oxygen ? If it were pure nitrogen ? Recall the ex- ■ 
 periments with oxygen ? 
 
 Air. 
 
 13. Take a tumbler partly filled with lime-water and 
 expose it to the air of the room for an hour or two ; can 
 you see any change ? What else is proven thus to be in 
 the air? 
 
 14. Fill part full a wide-mouthed bottle with air taken 
 from near the fioor of the school-room, and add half an 
 inch of lime-water ; shake the water well in the bottle. 
 Repeat the experiment, taking the air from near the 
 point of influx ; does the lime-water indicate the presence 
 of CO,? 
 
 15. In the same way test a bottle of air taken from 
 different points near the ceiling. (How can you get a 
 bottle of-air from any point in the room ?) 
 
 16. Is the CO, more abundant in one place than an- 
 other ? Why is it ? Test a bottle of air taken from out 
 doors. 
 
 17. What is the fruitful source of CO, in a school- 
 room? 
 
 18. Fill a small vessel with snow and salt, and watch 
 the outside surface of the vessel closely ; what does this 
 experiment prove to be in the air besides the gases 
 already shown to be there ? 
 
 ig. Place a small amount of chloride of lime in a dish, 
 and let it stand a short time ; can you notice any 
 change ? Explain. 
 
March] CHEMISTRY. 285 
 
 20. Look at a sunbeam as it streams into the room ; 
 what does it prove the presence of in the air ? 
 
 21. What contrivance do animals have for straining 
 the solid particles from the air before it enters the lung ? 
 (See Respiration for April.) 
 
flDeteoroIOG^. 
 
 March is the fickle month of the year, and the ap- 
 proach is usually awaited with feelings of mingled hope 
 and dread. To most people, all semblance, even, of 
 natural law appears to be wanting in the spiteful play 
 of the elements that are apparently uncontrolled. In 
 the gales that generally blow, now from one direction, 
 now from another, in the wintry days that are sometimes 
 slipped in between those having the genuine touch of 
 spring, and in the cautiously swelling buds that often 
 come forth only to be nipped by the last lagging frosts, 
 ttiere is, indeed, good ground for the reputation that 
 the month sustains. It will be no less instructive, how- 
 ever, to try to trace the sudden changes of this rnonth to 
 their causes, than it is in those months of more steady 
 meteorological behavior. 
 
 1. In which one of the preceding months was the 
 temperature nearest that of the present one ? 
 
 2. Compare the causes that combine in each month to 
 produce the temperature noticed. In what way are the 
 causes different ? 
 
 3. In what respect are the causes which operate now 
 the same as those present in September ? 
 
 4. What influences give to March and September their 
 different character ? 
 
 5. Compare the two months as to temperature; is 
 there any correspondence in the average temperature or 
 in the rate of change ? 
 
 S8$ 
 
March] METEOROLOGY. 287 
 
 6. Compare the, rate of variation witli that of each 
 month since the lowest temperature of the year was 
 reached ; is the rate increasing or diminishing ? 
 
 7. Make a similar comparison with the months preced- 
 ing the date of the lowest temperature ; how does the 
 rate during, that period compare with the rate which 
 follows the minimum point ? 
 
 8. Compare the barometric record with that of Sep- 
 tember ; what is the mean height and the greatest range 
 of movement in each month ? ' 
 
 9. Compare, in the same way, with the record for 
 December ; with which month does it most nearly 
 correspond ? 
 
 10. Can you, from your record, determine whether or 
 not the height of the barometric column is affected by 
 cold? 
 
 11. At what temperature during the month has it stood 
 highest? At what temperature, lowest? 
 
 12. Can you find any relation between the character of 
 the weather and the height of the barometric column ? 
 
 13. What is the prevailing wind this month ? Is it 
 generally cold or warm ? 
 
 14. What was the prevailing wind for September ? , For 
 December ? 
 
 15. What wind prevailed when the temperature was 
 lowest ? When it was highest ? 
 
 16. What wind brings a cloudy sky ? Is it like the 
 preceding months in this respect? 
 
 17. Has the character of the clouds changed since 
 December ? Compare with those months in amount of 
 cloudiness. 
 
 18. Is the number of rainy days greater or less than in 
 the winter months ? 
 
288 NATURE STUDY. [Marcli 
 
 19. From what directions do the heaviest rains come ? 
 
 20. Are the rains followed by cooler or warmer 
 weather ? 
 
 STUDIES OF SIGNAL SERVICE MAPS. 
 
 ii. In what quarter of the country have Low Areas 
 most frequently appeared ? Compare with September 
 and December. 
 
 22. What has been the course of the great storms dur- 
 ing the month ? How does the path compare with that 
 of previous months ? 
 
 23. Can you tell what influence the Great Lakes have 
 had upon their course ? The mountains ? The river 
 valleys ? 
 
 24. Where has there been the heaviest rainfall ? Com- 
 pare with September and December. 
 
 25. Is the amount of rainfall increasing or decreasing, 
 as compared with the winter months ? 
 
 26. What has been the lowest temperature recorded? 
 Compare with September and December. In what region 
 was it recorded in each case ? 
 
 27. Compare the isotherms that cross the country this 
 month with those of Septemben Is there any difference 
 in general direction ? 
 
 28. What is the most northern isotherm this month? 
 In September ? What does this indicate ? In the same 
 way compare the most southern isotherms. 
 
 29. Do the isotherms bend about the Great Lakes the 
 same way in both March and September? Compare with 
 December. 
 
 30. In the same way note the effects of the mountains 
 and coast lines in the different months. - 
 
Hstronom^. 
 
 March, the herald of spring, is a month in which 
 observations under this head are fraught with especial 
 interest and profit. The sun, mounting the meridian, as 
 shown by the shortening shadow^ and_ creeping almost 
 stealthily northward around the horizon, mere loth to 
 close his eye at night, more eager to begin his labors in 
 the morning, seems instinct with plans for a season 
 which, though ten thousand times repeated, is ever new. 
 The teacher who fails to seize the conditions presented 
 at this time, loses one of the best opportunities of the 
 entire year to broaden and strengthen his pupils' concep- 
 tion of the universe. It is wrong to suppose that the 
 formation of the great conceptions which are necessary 
 for an intelligent appreciation of nature is a matter that 
 maybe postponed tilla definite time, and then be gained 
 at once. They are never gained except through growth, 
 and, whether physical or mental, that implies small addi- 
 tions through patient and prolonged observations. 
 
 1. Can you find any previous month in which the noon- 
 marks correspond to those recorded during this one? 
 
 2. What suppositions regarding the movements of the 
 earth can you make which will account for the observed 
 facts ? What is the correct one ? Give the proof. 
 
 3. When did the noon shadow begin its retrograde 
 or backward movement? Has the rate of movement been 
 uniform since that time ? 
 
 4. In what previous month was the rate of the advance 
 
 2S9; 
 
290 NATURE STUDY. [March 
 
 movement of the noon-marks the same that it is now 
 in the retrograde movement ? . Using a globe, explain 
 why it is so. 
 
 5. On what date this month do you find equality of 
 day and night ? For how much of the earth is this true? 
 This is the Vernal Equinox. 
 
 6. How long since this was the case before ? Count 
 the days, using the almanac. When, between those 
 two dates, was there the greatest inequality ? 
 
 7. How many complete seasons have elapsed since the 
 same equality was noticed before ? 
 
 8. How many seasons yet remain to make a full year ? 
 Count the days ; what do you notice about the relative 
 length of the two parts of the year ? 
 
 9. What suppositions can you make which will account 
 for the observed inequality in the two parts of the year — 
 that part including fall and winter, and that including 
 spring and summer ? Find out which supposition is 
 correct. 
 
 10. What effect, if any, must this inequality in the two 
 parts of the year have upon the seasons included in those 
 parts respectively ? 
 
 11. On the date when a day and night are equal, this 
 month, note on the horizon the points of the rising and 
 setting sun. In what previous month did they coincide 
 with those of the present ? 
 
 12. How long has it been since the sun rose and set in 
 the same place that it does now ? Explain the facts. If 
 necessary, illustrate with a globe. How far has the sun 
 moved along the horizon since the shortest day of the 
 year ? Since a day and night were equal before ? Using 
 a globe, explain. 
 
 13. When day and night are equal, measure the angle 
 
March] ASTROMOMY. 2$t 
 
 that the sun's rays make with the earth ; can you deter- 
 mine, from what you observe, your latitude ? 
 
 14. Can you by the same means determine your 
 latitude on December 20 ? 
 
 15. What fact would it be necessary for you to know 
 in order to determine your latitude in the same manner 
 on any day of the year ? 
 
 16. In what latitude is the day longest in this month ? 
 Where are they increasing in length most rapidly ? 
 Explain this. (See April Astronomy for remarks on the 
 use of symbols.) 
 
 17. For whom does the sun rise for the first time in 
 some months, about the middle of this month ? For 
 whom does it set ? 
 
 18. It will be noticed that Jupiter has changed from an 
 evening to a morning star within the last month ; explain 
 how the change has been made. (See Astronomy f6r 
 September for the relative distances of the planets from 
 the sun.) 
 
 19. The period of revolution of Jupiter is twelve of 
 our years, lacking fifty days. Its time of rotation is four 
 and a half minutes short of ten hours. Its mean diameter 
 is eighty-five thousand miles, but there is a difference of 
 five thousand miles between its equatorial and polar 
 diameters. Its volume is over thirteen hundred times 
 that of the earth, but it weighs only three hundred times 
 as much. Its mean distance from the sun is four 
 hundred and eighty millions of miles. 
 
 20. Make as large a circle as possible, on the blackboard, 
 to represent Jupiter's orbit, and another to represent that 
 of the earth ; and upon the latter locate the earth at the 
 point where it is to be found this month ; in what position 
 must Jupiter be to appear as morning star ? 
 
292 NATURE STUDY. [March 
 
 21. How long will it continue as morning star? 
 
 22. When a planet is seen in the same direction as the 
 sun, or, in passing by it, approaches nearest to it, it is 
 said to be in conjunction with the sun. It is inferior con- 
 junction, if the planet lies between the earth and sun, 
 superior conjunction if the planet lies on the opposite side 
 of the sun from the earth. When a planet is on the 
 opposite side -of us from the sun, that is i8o° from 
 superior conjunction, it is in opposition. 
 
 23. In what positions will the earth and Jupiter be 
 farthest apart ? When will they be closest together .? 
 What will be the distance between the planets in each 
 case ? 
 
 24. Does Jupiter present to us the same phases that 
 are shown by Venus and our moon? 
 
 25. Constellations same as preceding month. ~ 
 
 Reference. Humboldt Library : No. 20, Romance of Astronomy. 
 
(Beograpb?. 
 
 EURO-ASIA. CLIMATE. 
 
 By consulting good physical maps, it will be found that 
 the climatic conditions of Euro-Asia are vastly different 
 ' from those presented by the Americas in corresponding 
 latitudes, and that there are also marked contrasts in the 
 same latitude in its own wide extent. The study should 
 be supplemented by sand modeling as before, but the 
 same precautions necessary in the use of devices in other 
 subjects apply with equal force here. (See Astronomy 
 for April.) 
 
 1. What, is the general direction of the great air- 
 currents over the northern part of Euro- Asia ? Compare 
 their direction on the eastern and western coasts; can 
 you account for the variation that you notice ? 
 
 2. Note the direction of the wind south of the Hima- 
 laya Mountains ; how does its character differ from that 
 on the northern slope ? 
 
 3. What contrasts in climate are presented between 
 that part of the continent lying north, and that part lying 
 south of the great axis ? 
 
 4. Contrast the two regions with those of the same 
 latitude in North America. 
 
 5. In which of the two continents are the conditions 
 more favorable for uniformity of climate ? Why ? 
 
 6. In what part of Euro-Asia would you expect the 
 
 893 
 
Z94 NATURE STUDY. [March 
 
 greatest extremes ? What conditions are present to pro- 
 duce them ? Study the course of the isothermal lines. 
 
 7. Where would you expect the greater uniformity of 
 climate, north or south of the Himalayas ? Why ? 
 
 8. Compare the temperature of the eastern and western 
 coasts ; can you see causes for variation ? 
 
 9. Compare the coasts with the interior ; what cause 
 operates mainly to produce variation ? 
 
 10. Compare the variations mentioned in (6) and (7) 
 with corresponding regidns in the Americas ; can you see 
 reasons for a difference ? 
 
 11. Contrast the climatic effects of the Gulf Stream' 
 with the Japan current, and account for the difference in 
 climatic influence. 
 
 12. In what r-espect are the climatic conditions on the 
 southern coast of Euro-Asia different from those of the 
 Gulf coast of North America ? In what respect are they 
 alike ? 
 
 13. In what respect do the conditions differ on the 
 Mediterranean Sea from those on the southern coast of 
 Asia ? 
 
 14. What influences combine to produce the heavy 
 rainfall of southern Asia ? Compare with southern 
 Europe. , 
 
 15. Compare the region of heaviest rainfall with that^ 
 of North America ; what similarity do you notice in the 
 location ? Why is the amount less in the latter con- 
 tinent ? 
 
 16. Contrg.st the rainfall of the great area north of the 
 continental axis with that south of it ; why does it 
 diminish" toward the north? 
 
 17. Consider the rainfall in the great peninsulas and 
 
March] GEOGRAPHY. 295 
 
 peninsular projections that extend south from the con- 
 ^tinent of Euro-Asia? 
 
 18. Compare Arabia with Hindostan ; can you account 
 for the difference ? In the same way compare the Malay 
 peninsula with that of Spain. 
 
 19. How can you account for the difference in rainfall 
 in the British Islps and Newfoundland ? 
 
 20. Why is the rainfall north of the continental axis 
 in Europe greater than that north of it in Asia? 
 
 21. How can you satisfactorily account for the desert 
 regions in the highlands of Asia ? 
 
 22. What reason can you assign for the desert of 
 Arabia ? 
 
 23. The monsoons which blow from May to October 
 toward the southern Asiatic coast from the southwest, 
 and from October to May in the opposite direction, i. e , 
 from the northeast, are the important climatic factors of 
 this region. 
 
 24.. Have you learned anything in physics about air 
 which will help you to explain the monsoons and their 
 change of direction ? > 
 
 25. What climatic conditions, favor the largest cities of 
 southern Asia ? 
 
 26. Are there any cities that have prospered under 
 adverse climatic conditions ? 
 
 27. How does the climate of a country affect the char- 
 acter of a city ? 
 
 28. Contrast the character of the people of southern 
 with those of northern Europe ; to what extent may the 
 differences noted be attributed to contrasts in climate ? 
 
 29. Are there any noticeable differences between the 
 people that live in the mountainous regions and those of 
 
29*5 NATURE STUDY. [March 
 
 low countries that are due to climatic contrasts ? Com- 
 pare those on the coasts with those in tlie interior. 
 
 30. Can you see any constant relation between the in- 
 telligence and thrift of a people and the climate, in a 
 study of Euro-Asia ? 
 
(Beolog?. 
 
 During this month observations on frost action should 
 be continued. The effects of freezing and thawing will 
 be shown in various ways. The manifestations of these 
 forces are usually very slight, and they will possess interest 
 and be instructive only as the pupil can be led to picture 
 ■in his own mind what the results must be after a great 
 lapse of time. The idea of time is one for which the 
 teacher should work with the pupils unceasingly. 
 
 Geological pictures have not always presented them- 
 selves to the student of nature as they now do to those 
 who are imbued with the more modern notions as to 
 nature's way of doing. Formerly the pictures were filled 
 with catastrophic action, which annihilated the old, and as 
 suddenly established a new order of things. Then came 
 a long time of absolute rest, or at least a period of trifling 
 change. Now, one sees in the picture constant unrest, 
 it is true, but modification so slight and so gradual, that 
 nothing is destroyed except those things that, apparently 
 through a loss of plasticity, fail to keep pace with the 
 incessant change. 
 
 Thus far w.e have examined what may be considered 
 some of the mechanical agencies which are at work mold- 
 ing and changing ,the face of the globe. There are 
 others equally potent and certainly of no less interest, 
 though they are not matters of such common observa- 
 tion. The agencies now meant are those called organic, 
 and to gain some conception of these we will include in 
 297 
 
298 NATURE STUDY. [March 
 
 our study for this month a piece of coral. In many 
 places, pieces of coral may be found in the common 
 stones that are abundant — limestones. When they cannof 
 be so obtained, it often happens that some of the pupils 
 possess specimens of their own. At least, it will be com- 
 paratively easy to secure clam, mussel, oyster or snail 
 shells, and these will give some idea as to how mineral 
 matter may be deposited by animals, which is a necessary 
 conception. From this, it should-be the aim to have the 
 pupils picture for themselves the history of the great beds 
 of limestone. * 
 
 1. Put a small piece of a shell of some kind into a test- 
 tube and add a little acid. (See Mineralogy for Janu- 
 ary.) Does this recall any experiments previously per- 
 formed ? 
 
 2. What kind of stone does this remind you of ? (See 
 Mineralogy for January.) 
 
 3. Examine an oyster, clam, or mussel as it lies on the 
 half shell ; also look carefully at the outer surface of the 
 shell. Can you tell how the animal forms this shell ? 
 
 4. Can you see the starting point of growth ? 
 
 5. Can you tell whether or not the shell grows in thick- 
 ness ? 
 
 6. Can you find out from what part of the animal the 
 material is secreted which increases the width of the 
 shell ? 
 
 7. Notice the thin membrane that lies closely against 
 the inner surface of the shell ; this is the mantle of the 
 animal. 
 
 8. Examine a piece of coral ; what kind of a substance 
 does it appear to be ? 
 
 9. In what respects does it differ from most kinds of 
 stone ? 
 
March] GEOGRAPtlY. 299 
 
 10. Use the acid test ; what stones that you have ex- 
 amined before does it resemble ? 
 
 11. If you have a specimen of the branching coral, ex- 
 amine the curious little rosette like pits along the sides ; 
 what similarity do you find among them ? 
 
 f 2. These little pits were once occupied by small jelly- 
 like animals (not insects, as we frequently hear them 
 named) ca,lled coral polyps. As they grew, they secreted 
 the ston)f_ substance, tiot as the oyster does, in a covering, 
 but in the lower part of the body. These minute animals 
 can live only in the warm, clear waters of the tropical 
 seas, and at a depth not exceeding one hundred and 
 twenty fee,t. . They are so small and delicate that one 
 would almost at first think that they would have to live 
 in the quiet places of old ocean, but the reverse is the 
 case. Can you see why the dashing waves and the sweep 
 of great ocean currents are necessary for their existence ? 
 You can scarcely make a mistake in the answer. The 
 myriads of these little polyps which live together, in the 
 course of time build up great masses of stone. The 
 waves break off the branches, which settle to the bottom, 
 and in this way a solid wall is formed. These are often 
 built out a little distance from an island, and coming to 
 the surface form coral reefs. These great rock walls are 
 sometimes thousands of feet deep ; what reasonable sup- 
 position can you make which will account for this, since 
 the polyps can live only at the depth given above ? 
 
 13. Judging from the location where the polyps live, 
 what would be the effect finally upon their stony struc- 
 ture ? 
 
 14. Look closely at the texture of the strong coral ; if 
 it were to be worn away by the water^ would it likely 
 make a fine or a coarse material ? 
 
300 NATUR& STUDY. [March 
 
 15. What would become of the material thus worn off, 
 as well as that wh'ich would be derived from the shells of 
 dead animals such as the clam and oyster ? 
 
 16. Would this material retain any of the form of the 
 original shells or corals ? 
 
 17. What property of the original shell or coral would 
 still be retained by the material worn away ? 
 
 18. In the examination of any of the stones that you 
 have seen, have you found any fragments of corals or 
 shells ? 
 
 ig. What would such fragments indicate as to the ori- 
 gin of the stones ? 
 
 20. In what kind of stones were such fossils found ? 
 What does that tell as to their history? 
 
 Reference. Humboldt Library : No. 6, Town Geology ; No. 
 no Story of Creation. 
 
HDineralog?. 
 
 It will be useful at this time to begin a little closer 
 study of the minerals that may have been collected dur- 
 ing the year. They may be readily sorted ^nd classified 
 by very small pupils with respect to their structure, which 
 in many cases is quite obvious to the naked eye. The 
 external form of most of the minerals in their collections 
 has, no' doubt, been determined by forces which have 
 had nothing to do with forming the mineral originally. 
 That is, they are probably fragmentary and angular, or 
 rounded as the water-worn pebbles. Here the external 
 form is of no use in the description of the mineral. 
 Sometimes, a few may be found whose form is not due to 
 such causes, and attention should be given to them 
 as they occur. 
 
 1. Look among your collection for stones that areseen 
 to be hollow ; sometimes they are rounded pebbles- so 
 worn away as to expose the hollow within. Such a stone 
 is called a geode. 
 
 2. Note the inner surface of the geode ; is it covered 
 with crystals or is it smooth ? Sometimes its inner sur- 
 face is covered with a layer full of rounded protuberances. 
 This forni of mineral is said to be botryoidal. 
 
 3. Haye you any stones in your collection which were 
 formed in rounded masses ? An examination of the sur- 
 face will usually show at once whether they are water- 
 worn or not. Such stones are called concretions, and are 
 said to be concretionary. , 
 
 30J 
 
302 Nature study. [March 
 
 4. Have you any specimens in which the material is 
 arranged in layers, as in slate ? This is said to be 
 stratified. 
 
 5. Sometimes about springs of certain kinds the water 
 deposits a porous incrustation of rocl<. It is very light, 
 and often sponge-like in appearance, and is called 'tufa. 
 It is said to be tufaceous. 
 
 6. In caves, sometimes the water which drips from the 
 roof leaves hanging an icicle-like mineral deposit which 
 is called a stalactite. The rock is described as stalactitic. 
 The water dripping to the floor there heaps up a mound- 
 like rock which is called a stalagmite. Such a rock is 
 stalagmitic. 
 
 7. Can you find in your collection any distinct crystals ? 
 Are they perfect ? How many faces have they ? 
 
 8. Examine some specimen that clearly shows a gran- 
 ular structure, and by cafefully tapping it separate some 
 of the grains. Are they crystals ? Are there any per- 
 fect crystals among them ? Such minerals may be 
 described as coarsely or finely granular, according to the 
 size of the grains. 
 
 9. When the grains are too small to be detected by 
 the naked eye, the mineral is compact. 
 
 10. Procure a piece of mica ; it is sometimes used in 
 stove-doors. What is the peculiarity of structure ? It 
 \?, foliated. 
 
 11. If possible, procure a small piece of asbestos; 
 such a mineral is fibrous. 
 
During this tnontli, usually, great abundance of ma- 
 terial for outdoor study appears. The calendar started 
 in the previous month will rapidly fill up, and as the 
 days go by will prove to be an interesting and instruc- 
 tive record. Collections of every kind should be en- 
 couraged, and informal talks and discussions should be 
 permitted as often as time and the disposition of the 
 pupils will warrant. 
 
 GENERAL OBSERVATIONS. 
 
 1. Watch for the first appearance of earthworms ; 
 why are they so abundant after a rain ? Do they come 
 down in the rain ? 
 
 2. Let the pupils each select and measure off a square 
 yard of ground in different locations and count the num- 
 ber of entrances to burrows that are found. What is the 
 average ? 
 
 3. In what locations are they most numerous ? Where 
 are they fewest ? 
 
 4. What is the meaning of the small heaps of earth at 
 the entrance of a burrow ? 
 
 5. How do they bore their way through the ground ? 
 Put one or more in a glass of damp earth for a few days 
 and watch it. 
 
 6. Carefully clean away the little heaps of earth from 
 about the burrows in a square yard, and the next morn- 
 ing gather all that has been cast up during the night, 
 
 303 
 
304 NATURE STUDY. [April 
 
 Dry, and weigh it ; at the same rate how much would be 
 brought to the surface on an acre in one night ? In three 
 months ? 
 
 7. Do they bring up as much in day-time as they do 
 at night ? What kind of weather seems to suit their 
 work the best ? 
 
 8. What must be the effect of their work upon, the 
 soil ? How must it affect objects lying on the surface of 
 the ground ? Notice stones and flag pavements that 
 have begun to sink. 
 
 9. Follow out a. burrow and find its depth, and make a 
 diagram of it. Is there more than one worm to a bur- 
 row ? The burrow may be followed by using a small 
 wire probe, the ground being dug away as it is pushed 
 carefully into the hole. 
 
 10. Does the earthworm eat? If so, what is its food 
 and when does it feed ? What are its enemies ? Does 
 it fight or seek safety in flight ? Upon what does it de- 
 pend as means for concealment ? How do birds find 
 them ? 
 
 11. Why is it so much alike on all sides? Why is it 
 not exactly alike all around ? 
 
 12. In what respect does it resemble a snake? How 
 does it differ from one ? Can you see why it differs ? 
 
 13. Why are its two ends so much alike? Are they 
 exactly alike ? Why are they at all different ? 
 
 14. Compare its movements with those of a snake ; 
 can you find any scales or legs ? 
 
 15. Draw it gently backward through the fingers and 
 examine its sides under a lens. Count the segments of 
 the body ; do they vary in different specimens ? 
 
 16. Does the earthworm breathe ? Look for respira- 
 tory movements along the body. 
 
April] ZodlOGV. 305 
 
 17. Can it live in water ? Expose a worm on a piece 
 of paper to the siui ; is there any evidence of distress ? 
 Can you tell what ails it ? Put it into a dish with a little 
 water in it and expose again; does it seem asuncom- 
 fortable as before ? 
 
 18. Examine the worm in a good light with a lens ; 
 can you see any trace of a ci-rculation ? Lying along the 
 back is a pulsating tubular organ which assists in keep-' 
 ing the circulating fluid in motion. The true blood is 
 not red, but rather milky in appearance, and does not cir- 
 culate in closed vessels as in our own bodies. 
 
 19. Can the earthworm see objects? What plan can 
 you devise which will fairly test this ? Does it distin- 
 guish between light and darkness ? 
 
 .20. Can it hear ? What evidence can you gather on 
 this point ? 
 
 21. Test it for the sense of touch. Also for the sense 
 of smell. 
 
 BIRDS. 
 
 1. What influences bring the birds north in the spring ? 
 
 2. What do those that arrive this month have to feed 
 upon ? 
 
 3. Are there any that feed entirely while on the 
 ground ? Are there any that never feed on the ground ? 
 Have you noticed any taking food while in flight ? 
 
 4. Why do some birds hop while others walk or run ? 
 Why do certain birds climb trees ? Why cannot they all 
 do it?- 
 
 5. Compare the flying of different birds ; what things 
 determine the character of the flight ? Notice shape of 
 body, wings, etc., and the proportion of the different 
 parts. 
 
 6.- What enables a bird to have such speed in flight ? 
 
3o^ ■ NATURR STUDY. [April 
 
 Compare the line of flight of different birds ; is there any 
 uniform difference between those which fly great dis- 
 tances, and those that fly but a short distance at a 
 time ? 
 
 7. Does the size of the tail affect the character of the 
 flight ? Is the tail used for any other purpose than that 
 of assisting in flight ? 
 
 8. Are there any good flyers that have very short 
 tails ? Is there any substitute for the tail in such cases ? 
 
 9. How do birds dispose of their legs when flying? 
 Compare those of widely different kinds. 
 
 10. How do birds manage to cling to a small twig 
 when asleep ? Have you found any that do not roost in 
 trees ? 
 
 11. How do birds seize their food? Are there any 
 that use both claws and beak ? Are there any that use 
 but the beak ? 
 
 12. Do you know of any birds that live upon the flesh 
 of other animals ? How do they differ from those that 
 live on insects and seeds ? 
 
 13. At what time do birds sing most ? Why do they 
 sing ? Which sings the more, the male or female ? 
 
 INSECTS. 
 
 In the study of insects, it is necessary to collect them 
 in some way in which they may be speedily killed, and 
 yet not be spoiled for examination. This may be done with 
 a cyanide bottle, prepared as follows. Drop into a wide- 
 mouthed bottle three or four lumps of cyanide of potas- 
 sium the size of a small marble. Pour in half an inch of 
 water and then sprinkle evenly with plaster of Paris, until 
 a dry cake is formed. Wipe inside and outside with a 
 dry cloth and close with a tight cork or cap. Any drug- 
 
April] ZOOLOGY. 307 
 
 gist will prepare one for a few cents. A wide-mouthed 
 morphia bottle is a very convenient size. 
 
 Insects dropped into this bottle will be quickly killed 
 and yet preserved in a perfect state for examination. 
 
 Insects may be mounted and preserved thus : slice 
 ordinary bottle corks into pieces one-fourth of an inch 
 thick and g'lue them to the bottom of a box or tray. A 
 cigar-box answers the purpose very well. Pass a pin 
 through the insect, in beetles through the right-hand half 
 of the abdomen, in butterflies, etc., through the center of 
 the middle division of the body, and set it upright in 
 the cork. Keep a small camphor ball in the box, to kill 
 the pests that attack them. 
 
 Some insects, such as butterflies, etc., must be dried 
 with wings spread before being mounted permanently in 
 a tray. Take two strips of smooth, soft wood three 
 inches wide and about two feet long. Leaving a space 
 one-fourth inch wide between them, nail them side by 
 side to two blocks of wood, one on each end. The 
 upper surface of these blocks should be cut slightly 
 slanting toward the middle, so that the strips when nailed 
 on will be somewhat trough-like. Tack underneath the 
 space between the strips a piece of soft wood, card-board, 
 or cork. Pass a pin through the body of the insect, as 
 directed above, and pin it fast to the cork, placing its 
 body in the space between the strips. Draw the wings 
 forward to the natural position, and fasten by pinning 
 narrow strips of paper across them. 
 
 1. Collect and sketch the insects that first appear ; 
 when are they to be found ? 
 
 2. Are they youiig ones-, or have they lived through 
 the winter ? 
 
 3. What is their food ? Of what are they the prey ? 
 
3o8 NATURE STUDY. [April 
 
 4. What means of escape and defense have £hey ? 
 
 5. When are they more frequently abroad, in daytime 
 or night ? 
 
 6. What modes of concealment have they ? 
 
 7. How does their flight differ from that of a bird ? 
 
 8. Do any insects possess wings .without having the 
 power of flight ? 
 
 9. How does the number of wings vary in different 
 kinds ? How are they used ? 
 
 10. How do they walk or run? Make a sketch show- 
 ing the order in which they move their legs. 
 
 POND LIFE. 
 
 1. Secure a mass of frogs' eggs from a pond or ditch 
 and place them in a jar of water. Toads' eggs are dis- 
 tinguished by their being in long strings. 
 
 2. What are the earliest signs of life ? Can you dis- 
 cover movements before the eggs are hatched ? 
 
 3. As soon as hatched, examine one of the tadpoles 
 closely ; how does it swim ? 
 
 4. Has it any appendages ? Look closely about the 
 mouth for gills ? 
 
 If a microscope can be obtained, place one of the little 
 creatures on a piece of glass with a little water (a watch 
 glass is best) and examine the gills. The blood flow 
 thus revealed is a thing of rare beauty. 
 
 5. It is difficult to preserve the same specimens 
 through all the changes, and new ones must be obtained 
 as needed. 
 
 6. What becomes of the external gills ? How do they 
 breathe? Look just behind the mouth for a small open- 
 ing ; this leads to internal gills. 
 
 7. What is their food ? Is the number of tadpoles 
 
April] ZOOLOGY. 3°9 
 
 which develop into frogs relatively large or small ? 
 Why ? 
 
 8. Do you notice anything different in the early life of 
 a toad from that of a frog ? 
 
 RESPIRATION. 
 
 1. Standing erect, inhale slowly a full breath. Through 
 what openings does the air enter ? 
 
 2. Can you close the mouth and inhale through the 
 nostrils ? Can you inhale equally well through the mouth 
 alone ? 
 
 3. What muscles of the trunk seem to be most con- 
 cerned in inhaling air? In exhaling? 
 
 4. What changes occur in the shape or size of the chest 
 in breathing ? With a string or tape measure find out 
 how many inches the chest varies in size. 
 
 5. In what part does it change most ? 
 
 6. Is the air filling the lungs the cause or effect of 
 the expansion of the chest? Close the mouth and nos- 
 trils and try the movements of inhalation. 
 
 7. What experiments in Physics will explain the process 
 of inhalation ? 
 
 8. How do the ribs move in inhalation ? In exhala- 
 tion ? 
 
 The chest cavity is separated-from that of the abdomen 
 by a dome-shaped muscular partition called the dia- 
 phragrri. By contraction, the diaphragm is somewhat 
 flattened, and the.chest cavity is enlarged vertically, thus 
 assisting in inhalation. When relaxed, the contents of 
 the abdomen, which have been compressed during its 
 contraction, force it back into itsdome shape, thus a.ssist- 
 ing in exhalation. 
 
 9. What position is best for full breathing ? 
 
31° 
 
 NATURE STUDY. [Ap"l 
 
 10. What is the meaning of the occasional long breath 
 we take ? Of yawning ? 
 
 11. Why do sad thoughts cause us to sigh ? 
 
 12. Do the common animals, dog, cat, horse, cow, 
 etc., breathe through the mouth or nostrils? 
 
 13. What advantages in taking breath through- the nos- 
 trils ? 
 
 14. How do people who snore breathe, through the 
 mouth or nostrils ? Open the mouth and make full in- 
 spiration through both mouth and nostrils. Can you tell 
 where the snoring sound is formed ? 
 
 15. With a mirror examine the back of the mouth. 
 Note the fleshy flap hanging down toward the throat. 
 The air passes on both sides of this to 'and from the 
 throat when the mouth is open, and causes it to flutter 
 more or less rapidly, thus producing the peculiar iifand 
 of snoring. ; 
 
 16. Can you make the snoring sound with the mouth 
 closed ? 
 
 17. Count the number of respirations to-tke mifl^iiii^:, 
 take average per minute for five minutes. '\ 
 
 18. How do your movements affect the number of 
 respirations ? Take the number after vigorous exercise. 
 
 19. How do the movements affect the general charac- 
 ter of the respirations ? 
 
 20. In ordinary breathing are the lungs filled to their 
 utmost capacity ? Try breathing in additional air after 
 a quiet inspiration has ceased. 
 
 The extra amount thus taken into the lungs is called 
 complemental air. That which passes in and out in ordi- 
 nary quiet breathing is called tidal air. 
 
 21. After an ordinary expiration, can you still force 
 outward an additional amount? This is called supple- 
 
April] ' ZOOLOGY. 311 
 
 mental, of reserve, air. After all has been forced out that 
 is possible, some air still remains in the lungs; this is 
 called residual air. 
 
 22. Prepare a small amount of lime-water and breathe 
 into it through a tube. Does this recall any other exper- 
 iment ? 
 
 23. What was it that changed the lime-water in the 
 former, experiment ? 
 
 24. Try stirring fresh lime-water with a glass rod, so 
 as to mix it with pure air. Does it show the same 
 change ? 
 
 25. Is the air, when it leaves the lungs, of the same 
 composition it was when it entered them ? 
 
 26. What are the effects you have noticed upon your- 
 self when in a poorly ventilated room containing several 
 persons ? 
 
 27. Fill a jar with water and invert it in a pneumatic 
 trough, as directed in lessons on oxygen. Take full 
 breaths and by means of a tube fill the jar with air from 
 the lungs. 
 
 28. Test the air in various ways ; note the odor. Try 
 burning a splinter in it. Can you tell what the air lacks ? 
 What has become of the missing part ? What has it 
 gained from the body ? 
 
 29. Inwhat respect are our bodies like a burning stick ? 
 (See Chemistry for March and also previous lessons 
 in Physics.) 
 
 Reference. Humboldt Library : No. i, Light Science for Leisure 
 Hours. See " The dust we have to breathe.'' No. 92, Formation of 
 Vegetable Mold by Earthworms. 
 
Botany, 
 
 During this month much attention should he given to 
 germination, as the young plantlets appear. It is impos- 
 sible to cast in any single outline a set of directions which 
 will exactly suit the environment of every teacher. 
 The time has come, however, when teachers should 
 cease trying to follow some one else -step by step ; 
 no one has ever risen in his work by following, no matter 
 how perfect the leader. An outline, at best, can only- 
 furnish a teacher with hints and suggestions as to how he 
 may utilize his own conditions. It adds immensely to 
 the vitality of the work with the pupils, if the plants that 
 come up at random outdoors be used as specimens for 
 study. It is surprising how small a spot will furnish an 
 abundant supply for an entire school. That the whole 
 process of germination may be observed from the begin- 
 ning, however, it is well to have seeds planted in some 
 manner in the school-room also. There are many devices 
 that may be used successfully for this purpose, but, on 
 the whole, there is perhaps nothing better than some 
 suitable vessel filled with clean sand. 
 
 A pan that has proved useful and convenient is one 
 made of galvanized iron, thirty inches long, eight 
 inches wide and four inches deep. By filling it 
 two-thirds full of sand, space enough is left above 
 to admit of glass being placed over the young plants 
 if the weather be very severe ; but this precaution 
 is rarely necessary. By allowing to one pupil a space 
 
April] BOTANY. 313 
 
 of three inches, such a pan will accommodate eight 
 persons, and there will be a six-inch space left as 
 common ground in which odd or curious forms may be 
 grown, such as bulbs, underground stems, etc. Five 
 pans of this kind will equip, at a trifling outlay, an ordi- 
 nary school-room with a useful outfit that will last for 
 years. No trouble or time is required beyond what is 
 necessary to keep the sand moist and the pan near a 
 window. The pans when wejl made are water tight, 
 without being soldered, and will be found very useful in 
 other seasons in many experiments in physics and chem- 
 istry when pneumatic troughs are needed. The develop- 
 ment of buds may be observed by placing small twigs in 
 bottles of water. A few wide-mouthed bottles, such as 
 may be easily procured by the pupils, will enable them 
 to watch without trouble the development of the buds of 
 every different kind of tree and shrub in the neighbor- 
 hood. Some of the twigs start their buds, when treated 
 thus, quite slowly ; others develop almost at once, and 
 not a few not only put forth leaf and flower, but plenty 
 of roots too. The twig should not be more than six 
 inches long and should have a terminal bud, that its 
 functions maybe studied. 
 
 GERMINATION. 
 
 1. Plant some of the seeds that were gathered last fall. 
 (See September Botany.) With beginners use large 
 seeds of some kind first. Plant carefully, placing the 
 seeds in different positions and at different depths. 
 
 2. Make the conditions different for the same kind of 
 seeds. Place some in the dark, or cover with a tin cup 
 or flower pot. Plant some in dry sand. Keep some 
 cold and others- warm. 
 
314 NATURE STUDY. [April 
 
 3. As the seeds begin to grow, write a list of what ap- 
 pear to be the most favorable conditions for development. 
 
 4. Do different seeds, under the same conditions, grow 
 etjtially well ? 
 
 5. Where does the plant get its first food to give it a 
 start before it has either leaf or root outside the seed 
 co^ts ? 
 
 6. When the seed coats burst, as growth begins, closely 
 examine what is inside ; what parts of a plant can you 
 recognize ? 
 
 7. As growth proceeds, watch daily what becomes of 
 the different parts of the seed ; what parts do not con- 
 tinue with the growing plant ? What parts develop as 
 the plant grows ? 
 
 8. Are the seeds you find sprouting outdoors near 
 the parent plant ? Can you tell how they came to be 
 planted where they are ? 
 
 9. Scrape away the surface of the ground from some 
 spot and take up a box of earth that has been buried 
 several inches. Put this in a suitable, place and watch 
 for the sprouting of any seeds it may contain. Take up 
 a small box of earth from the surface in another place ; 
 how many different kinds of plants grow from it ? 
 
 10. In some place not likely to be. disturbed, mark off 
 a square yard of ground and Count the different kinds of 
 plants it produces. Can you tell where the seeds that 
 sprout in this space came from ? 
 
 11. With what adverse influences do the sprouting 
 seeds and young plants have to contend ? 
 
 12. Look for plants of the same kind in different loca- 
 tions ; compare the growth of those under trees or in the 
 shade of buildings with those away from such influences. 
 Compare those growing in sand with those in soil. 
 
April] BOTANY. 31S 
 
 13. Do they grow alike on different sides of a house ? 
 
 14. Compare the chances of those that start early with 
 those that sprout later. 
 
 A SEED. 
 
 Synopsis of the terms that may be used at the teacher's 
 discretion, in a study of the seed. 
 
 I. Outer parts. 
 
 Hilum or scar ; the point where it was attached 
 
 to the pod. 
 Micropyle ; minute opening near the hilum. 
 Seed coats ; outer, testa ; inner, tegmen. 
 
 II. Inner parts. 
 
 Cotyledons ; the thickened leaves in which nour- 
 ishment is stored. When there are two cotyle- 
 dons, the plant is a dicotyledon j when but one, 
 it is a monocotyledon' Find examples of each. 
 
 Plumule ; small terminal bud lying between the 
 cotyledons, or embedded in it when there is 
 but one. 
 
 Caulicle or Radicle ; small stem within the seed 
 coats. 
 
 Embryo ; the plantlet within the seed coats. 
 
 DEVELOPMENT OF BUDS. 
 
 1. Which seems to be in advance, the sprouting of the 
 seeds, or the unfolding of the buds ? 
 
 2. Which is the more serious loss to a plant, the de- 
 struction of a seed, or the loss of a, bud? Which are 
 destroyed in greater numbers, seeds or buds? 
 
 3. Compare, as well as you can, the ratio of the seeds 
 that are destroyed to those that produce plants with that 
 of the buds that are destroyed to those that survive. In 
 
3i6 NATURE STUDY. [April 
 
 the production of which does nafure seem to be the more 
 extravagant ? 
 
 4. Are the buds all equally advanced in all parts of the 
 tree? Compare the opposite sides'and the top of the 
 tree with the bottom. 
 
 5. Are they all equally advanced on the same branch ? 
 On the same twig ? Try to account for any irregularity 
 in development, you find. 
 
 6. Do all of the buds develop ? What is the location 
 of those that remain dormant, if any are found ? 
 
 7. Is there any advantage to the plant in having dor- 
 mant buds ? 
 
 8. Cut off the outer end of a few twigs and watch the 
 effect on the development of the buds that remain. Pick 
 off all the buds from a few twigs and watch the result. 
 
 9. What is the function or use of the terminal buds ? 
 Look for the former positions of the terminal bud on 
 the same branch ; why does it leave a scar each year ? 
 
 10. What is a bud ? To answer this, examine as large 
 a one as you can find (a lilac will do) that is just begin- 
 ning to swell. Dissect a bud and find in the center the 
 tender growing point. What is the difference between a 
 bud and a seed ? 
 
 11. Can you find any buds on the trunk of a tree? 
 What evidence can you find that they are there ? 
 
 12. Do roots produce buds? How do you account 
 for sprouts that sometimes come up from the roots of 
 trees ? 
 
 13. Examine some of the fruit trees for flower buds; 
 which unfold first, flower or leaf -buds ? 
 
 14. Do you find any buds growing about the same 
 point in pairs or clusters ? Do all of such buds develop ? 
 
 15. Are these buds always arranged in the same way 
 
April] BOTANY. 317 
 
 in the group? Does the arrangement differ in the same 
 plant ? 
 
 The following synopsis of the terms needed in the 
 study of buds is appended to assist the teacher. The 
 proper name should be given when it is needed in de- 
 scription. 
 
 "' BUDS. 
 
 I. As TO POSITION. 
 
 1. Terminal ; at the end of the twig. 
 
 2. Lateral ; along the sides of the twig. 
 
 (a) Axillary ; in the leaf-axil ; that is, the upper 
 
 angle between the leaf and the stem. 
 
 (b) Accessory ; buds clustered about the axillary 
 
 buds. 
 
 (c) Adventitious ; buds that are produced ir- 
 
 regularly on the branch or trunk. Often 
 develop when the regularly arranged buds 
 are destroyed. 
 Nodes are the points on the stem at which 
 the buds are produced ; internodes, the 
 spaces between the nodes. 
 
 II. As TO ACTIVITY. 
 
 1. Active ; those that develop. 
 
 2. Dormant ; those that form, but do not develop. 
 
 Note the effect on these of destroying the 
 active buds. 
 
 III. As TO COVERING. 
 
 1. Scaly; covered with dry, tough, bark -like layers. 
 
 2. Naked ; without scaly covering. 
 
 3. Hidden ; those buried under or in the bark. 
 
 ^ IV. As TO ARRANGEMENT. 
 
 I. Opposite ; two at the same node and opposite, 
 
3i8 NATURE STUDY. [April 
 
 2. Whorled ; three or more arranged around the 
 
 same node. 
 
 3. Alternate ; in ranks along the stem, not being 
 
 opposite or whorled. 
 
 UNDERGROUND FORMS OF THE PLANT AXIS. 
 
 This season of the year is an appropriate time in 
 which to study underground stems and those roots 
 which, preserved through the winter, are now ready to 
 send forth vigorous growths and make woodland and 
 meadow gay with early flowers. As great a variety as 
 possible should be collected. 
 
 1. if they grow in the neighborhood, gather the under- 
 ground part of the common blue flag (the iris), or calamus 
 (sweet flag), Solomon's seal, or blood- root. Are these 
 roots or stems ? What evidence can you find on either 
 side ? Can you find any evidence as to how long they 
 have been growing ? 
 
 2. Compare these with the common potato ; what 
 differences do you find ? What are the eyes of the 
 potato ? Plant some of these and watch how and where 
 the young potatoes are formed. What becomes of the 
 old potato ? The potato and all underground parts 
 like it are called tubers. Those like the blue flag are 
 called rhizomas. 
 
 3. Examine the thickened underground part of an 
 Indian turnip (Jack-in-the-pulpit). How does it differ 
 [com a tuber or a rhizoma ? It is called a corm. 
 
 4. Examine the underground part of a lily or an onion. 
 •Cut it so as to make various sections ; what part of a 
 
 plant does it most resemble ? What part of the plant 
 forms the overlying scales of the onion ? What forms 
 its solid base from which roots are produced ? Under- 
 
April] BOTANY. 319 
 
 ground parts like the lily and onion are called bulbs. 
 How do they differ from the forms previously examined ? 
 What, have they in common with them ? An onion is 
 called a tunicated bulb ; in the lily bulb and others, 
 where the layers are small, it is said to be scaly. 
 
 ■5. Examine the underground parts of the hepatica 
 or buttercup ; how do these differ from those first ex- 
 amined ? Are they roots or stems ? W.liere they are 
 clustered in this way they are said to be fascicled. Where 
 they are thickened they become tuberous. 
 
 6. Can you find any plants with a main root growing 
 straight downward ? This is called a tap root. These 
 become thickened sometimes so as to become conical, 
 spindle-shaped, napiform, or turnip-shaped. What ex- 
 amples of -these can you find among our common vege- 
 tables ? 
 
 7. Do stems ever produce roots above ground ? Un- 
 der what-conditions and for what purposes ? 
 
 8., Can you see what features distinguish a root from 
 a stem ? " ' - 
 
 9. Can you understand why such plants as many of 
 those mentioned above can produce early flowers ? 
 
In continuing the study of Light this month, we shall 
 find that images may be formed in a very different way 
 from that by which they were produced with mirrors. In 
 their explanation, however, it will be seen that nothing 
 is involved that has not already been considered in 
 previous lessons, except the fact of refraction and its laws. 
 If the work indicated for the preceding month has been 
 well illustrated, no difficulty will be found here. 
 
 1. Through a small hole in the window shutter admit 
 a beam of sunlight into a darkened room ; allow it to 
 strike the side of a glass vessel filled with water.- A use- 
 ful tank for this purpose can be made by any tinner for 
 a few cents. It should be about six inches long by four 
 in depth and width. The bottom and ends should be 
 made of tin, with edges turned in so as to admit of glass 
 sides being slipped in. Putty well on the inside. 
 
 2. Hold the vessel so that the beam will strike the 
 sides perpendicularly ; can you trace the path of the 
 beam through the water ? Can you trace it after it leaves 
 the water on the opposite side ? 
 
 3. Notice the kind of a line it follows from the point 
 where it enters the room to the place where it. should 
 strike the wall or a screen beyond the vessel of water. 
 
 4. Hold the vessel so that the beam will strike the 
 sides at an acute angle ; follow its course through the 
 water and to the screen. Do you notice any change in 
 
 320 
 
April] PHYSICS. 321 
 
 its course ? Compare its course with that which it follows 
 in the air. 
 
 5. Turn the tank around on a vertical axis and watch 
 the path of the ray ; upon what does its variation from a 
 straight line depend ? 
 
 6. A beam of light thus bent from a straight course 
 when it passes into or through different substances is said 
 to be refrac-ted. What difference do you see between re- 
 fraction and reflection ? 
 
 7. The direction in which a beam of light is refracted is 
 always referred to a normal (see 22, Physics for March) 
 drawn (within the refracting substance) to the point on 
 the surface where the beam enters it. When the beam 
 enters the water in the vessel, is it refracted toward or 
 away from the normal ? 
 
 8. Draw a norrfial to the point where the beam enters 
 the air again ; in what direction is the beam refracted ? 
 Turn the tank or vessel in different directions ; can you 
 find a position where the refracted beam does not take 
 the same direction with respect to the normal ? 
 
 9. Is there any position in which the beam is not re- 
 fracted at all ? 
 
 10. Place the end of a pencil or stick in a vessel of 
 water ; what doyou notice at the point where it enters 
 the water ? 
 
 11. -Make a drawing of the vessel, the water and pencil, 
 and, by lines, show the course of the rays of light that 
 passed upward through the water from the pencil. Do 
 you see the pencil, or its image, below the surface ? 
 
 12. In a tin cup, place a penny and hold it so that it 
 cannot be see when looking across the rim into the vessel. 
 Cautiously add water, and watch for the appearance of 
 the penny. Is it the penny or its image .that appears? 
 
322 NATURE STUDY. [April 
 
 13. As in (11), make a drawing showing the course of 
 a ray of ligtit from the penny to the eye. 
 
 14. Is it the reflected or refracted part of the ray from 
 the penny that brings what we see into view ? 
 
 15. Hold an ordinary lens or magnifying glass be- 
 tween the sun and a sheet of paper ; move the paper back 
 and forth until the light spot is brightest and smallest. 
 
 16. How large in diameter is the beam of light from, 
 the sun that strikes the surface of the lens ? Why should 
 it be conveyed to a point by passing through the lens ? 
 Before trying to answer this, examine the lens ; what do 
 you notice about its surfaces ? Draw a vertical section 
 so as to show the curvature of both surfaces ; construct 
 lines which will be normals to different parts of the 
 surface ; are they parallel ? If not, where would they 
 meet ? 
 
 17. Is any line that is normal to one surface, normal 
 also to the other ? 
 
 18. In a drawing similar to the one above, draw a line 
 on one side, representing a ray of light to the lens some- 
 where between its center and circumference ; construct 
 normals and shbw what its path would be on entering 
 and leaving the lens. To another point on the same 
 side of the lens draw a line representing another ray, and 
 in the same way show its course through the lens and 
 beyond. What is the relation of the two lines after 
 leaving the lens ? Can you now account for the bright 
 spot observed in (15) ? 
 
 19. Take a thin strip of wood three inches wide and 
 two and a half feet long. Mark off one side in inches. 
 Ill any convenient way mount a common single lens 
 magnifying glass so that the light will pass through it 
 horizontally and fall upon a screen. The latter may 
 
April] P/jysics. 323 
 
 consist of a piece of card-board six inches square. A 
 low block with a groove sawed in it to recive the card- 
 board, which may be fastened with glue or a tack, will 
 make a support. 
 
 20. Place the lens and screen on the strip of wood. 
 On the opposite side of the lens from the screen, place a 
 small lighted candle, and move it into a position where 
 it will throw an image on the screen. AVith which kind 
 of mirror was a similar image formed ? 
 
 21. Make a diagram of the lens, object, and image, 
 and trace (see 32, Physics for March) lines showing 
 the course of the rays of light from the object to the 
 image. 
 
 22. Place the lens so that the size of the image is the 
 same as that of the object ; draw lines showing why this 
 is so. 
 
 23. Place object and lens in such a position that the 
 image is less than the object ; can you show by lines 
 why it is smaller ? Is the image formed in each of these 
 experiments real or virtual ? In what ratio does the 
 image vary with the distance of the object from the 
 lens ? 
 
 24. Look through the lens at a letter or other small 
 object ; do you see the object,, or an image ? 
 
 25. Prove by lines which it is. If it is an image, is it 
 real or virtual ? Why is it enlarged ? Prove by drawing 
 lines showing their path of light from the object to the 
 eye. 
 
 26. Admit a beam of light through a small hole in the 
 window shutter. Hold a screen so as to catch the 
 spreading rays ; can you see the image of any objects 
 outside ? 
 
 27. Compare the image in position, size, etc., with the 
 
3^4 NATURE STUDY. [April 
 
 object ; how does moving the screen bacliward and for- 
 ward affect it ? 
 
 28. Why should an image form under these conditions ? 
 Make a diagram showing by a vertical section the posi- 
 tion of the object, the shutter, and the image on the 
 screen ; recall what was learned in March about reflec- 
 tion and the visibility of objects. 
 
 29. Allow a small sunbeam to pass through a prism (for 
 directions for making one, see Physics for September). 
 
 30. Note the rays that fall upon the screen, and com- 
 pare with the sunbeam. How many colors can you dis- 
 tinguish ? In a diagram, show the course of the beam 
 through the prism. 
 
 31. Catch all these colored rays on a concave mirror, 
 and reflect them to a screen ; what color is the light at the 
 focus ? What does this prove as to the sunbeam before 
 it strikes the prism? Which rays are most refracted as 
 they leave the prism ? Which the least ? 
 
 32. Hold some white object in the red rays ; what color 
 does it appear to be ? Try in the same way the different 
 colored rays ; what is it in this case that seems to deter- 
 mine its color ? 
 
 33. What colored rays are carried to the eye in each 
 case ? When the sunbeam, not refracted, falls on the 
 object, what color does it appear to be ? 
 
 34. Inordinary daylight look at some red object ? what 
 kind of light strikes it ? What kind must be diffused.from 
 it? Try in the same way objects of different colors. 
 The rays not sent to the eye from the object are ab- 
 sorbed by it. 
 
 35. What colored rays are absorbed by an orange ? 
 What ones are absorbed by a white surface ? By a black 
 surface ? 
 
April] PHYSICS. 325 
 
 36. Is color something belonging to the object itself ? 
 
 37. Can you apply what you have learned about refrac- 
 tion of light by a prism, to show how a rainbow is formed ? 
 Under what conditions is it seen ? Make a diagram show- 
 ing the relative position of the bow, the sun, and the 
 observer. 
 
 38. What is there in the atmosphere to break the sun- 
 light up into the colored rays ? How are these rays di- 
 rected to the eye of the observer ? 
 
 39. Can you give a reason why the colors in the rain- 
 bow stand in the order in which you se,e them? 
 
 40. Why is the rainbow in the form of an arc of a cir- 
 cle ? Did you ever see one in form of a circle, entirely 
 above the horizon ? Why ? Have you ever seen one at 
 noon ? Have you ever seen one in the west ? 
 
 41. Can you, from what you have learned, give any 
 satisfactory explanation of rings around the sun and 
 moon? 
 
Cbemistri?. 
 
 WATER. 
 
 1. Dissolve a small quantity of salt in a bottle or test- 
 tube of water ; when the salt disappears, is it destroyed ? 
 Is it changed to anything else ? Proof. Has it united 
 with the water ? 
 
 2. Fit a bent tube through a cork that will fit the flask 
 or test tube and gently heat it over your lamp. Hold the 
 vessel in such a position that the steam that comes through 
 the tube may be caught in a cool receiver. Taste the 
 drops of water that soon appear ; are they fresh or salty ? 
 Does this enable you to answer the last question in (i)? 
 
 3. What is this process called ? (See Physics for Oc- 
 tober.) 
 
 4. Take a small piece of perfectly clean glass ; place 
 upon it a large drop of hydrant or spring water, and hold 
 it over the lamp until it has evaporated. Is there any de- 
 posit left on the glass? What is it ? Can you burn it in 
 the flame ? What does the burning or the failure to burn 
 prove ? 
 
 5. Take a drop of the purest filtered water you can get 
 and evaporate it as in (4) ; is there any solid matter left? 
 
 6. What is removed from water by filtering it ? What 
 still remains in it ? Try filtering a salt solution, using 
 filter paper. (See 19, Cheraistry for February.) Can 
 
 ycu taste the salt in the filtrate, that is, in the filtered 
 part? 
 
 336 
 
April] CHEMISTRY. .327 
 
 7. Distil some hydrant or spring water as directed in 
 (2) and evaporate on your glass some of the drops formed 
 from the steam ; is there any deposit left? What did 
 distillation do for the water ? 
 
 8. How and where is distillation of water carried on in 
 nature ? 
 
 9. When it rains, catch in a perfectly clean- vessel some 
 rain water ; evaporate a drop of this in your glass. Is 
 there any solid matter left ? Compare it, as to purity, 
 with hydrant water filtered. 
 
 10. How does spring water gather its solid matters ? 
 What parts cannot be filtered out ? 
 
 11. Powder a small lump of gypsum, and add it to a 
 bottle of rain water, or distilled water. Shake it thor- 
 oughly and filter ; are there any traces ot the gypsum 
 visible in the filtrate ? 
 
 12. Dissolve some soap in hot water and keep the 
 solution in a bottle labeled Soap Solution. 
 
 13. Add a little of the soap solution to a test tube of 
 distilled, or rain water, and shake it. Add, also, some 
 of the soap solution to the filtrate obtained in (11) ; what 
 difference do you notice in the two tubes? The first is 
 called soft water, the latter hard water. 
 
 14. Boil some of the filtrate, and then add soap solu- 
 tion ; does boiling affect the hardness ? 
 
 15. Take a tumbler of lime-water and blow your breath 
 into it through a tube ; recall an experiment in Chemistry 
 for November. (See 24, Chemistry for November.) 
 
 16. Continue blowing until the water clears; this may 
 take some minutes. Filter. 
 
 17. Divide the filtrate, and test one part with the soap 
 solution ; is it hard or soft water? 
 
 18. Boil the other part of the filtrate, and test with 
 
328 NATURE STUDY. [April 
 
 soap solution ; compare with what you observed in 
 
 19. The hard water containing gypsum is said to be 
 permanent hard water ; that containing limestone or 
 chalk, is tempofary hard water. 
 
 20. The explanation of the formation of hard water in 
 the second instance is this : the carbon dioxide from the 
 breath unites with the lime in the water and forms car- 
 bonate of lime. By continuing the blowing the excess 
 of carbon dioxide dissolves the carbonate, and the water 
 containing .this in solution is hard. 
 
 21. Can you see why boiling temporary ^hard water 
 renders it less hard ? 
 
 22. Add to some of the filtrate obtained in (16) some 
 - clear lime-water ; when the mixture clears, test a little 
 
 of the clear part with the soap solution; is it soft or 
 hard ? Explain. 
 
 23. Which requires the greatest amount of soap to be 
 used in washing, hard or soft water? What difference 
 do you notice in the feel of the two kinds of water ? 
 
 24. An interesting test for a small quantity of salt in 
 water may be made as follows : Put a ten-cent piece into 
 a small amount of dilute nitric acid ; when it is dissolved, 
 evaporate the solution. Rediss^lve the crystals formed 
 in distilled water. This is silver nitrate, which also con- 
 tains some copper which gives the bluish tinge. Bot- 
 tle, in a clean dark-colored bottle, or else keep in the dark. 
 Label it properly. 
 
 25. Thoroughly wash and rinse two bottles or tumblers, 
 and partly fill each with pure distilled water. In one, 
 dissolve a piece of salt about the size of a pin-head. 
 
 26. Add a drop or two of the silver nitrate to the 
 beaker of pure water ; can you notice any change ? 
 
April] CHEMISTRY. ' ^ 329 
 
 27. Add a drop or two to the vessel containing the 
 grain of salt ; what change do you notice ? , 
 
 28. With the silver nitrate test the hydrant water, rain 
 water, spring water, and well water, if it can be ob- 
 tained 
 
The meteorological influences of April are usually of 
 a very different kind from those of the preceding months. 
 .For six months they have been negative in character, 
 but from now forth they are positive ; they no longer 
 play the part of a destroyer, but rather that of a creator. 
 These benign influences are to be seen and felt by all, 
 and the pupils, properly guided, will be interested in 
 tracing them to their cause. 
 
 1. Can you notice any difference in the character of 
 the wind this month ? To what is the difference due ? 
 
 2. What is the prevailing direction of the wind ? Has 
 it changed within the last month ? 
 
 3. In what month studied has the wind been most 
 variable ? 
 
 4. Is the prevailing wind accornpanied by wet or dry 
 weather ? Can you give a reason for the observed 
 facts ? 
 
 5. What wind usually accompanies a clear sky ? Com- 
 pare with previous months. 
 
 6. Are the clouds changed in their character this 
 month ? Notice their height and compare with previous 
 months. 
 
 7. Compare the fogginess of this month with that of 
 preceding ones ; can you account for the difference 
 noticed ? , , 
 
 8. Under what conditions are the heaviest fogs formed? 
 What conditions about you are especially favorable for 
 
April] MRTEOROLOGY. 331 
 
 their formation ? When fogs disappear, what becomes 
 of them ? 
 
 9. What difference do you notice between April rains 
 and those of the winter months ? 
 
 10. How does the amount of rainfall now compare 
 with that of October ? With December ? 
 
 11. Compare the number of rainy and clear days with 
 that of previous months. 
 
 12. Compare the temperature of this month with that 
 of March. 
 
 13. In what autumn month did the earth occupy the 
 same relative position with respect to the sun ? Compare 
 the temperature for the two months. How does the 
 "rate of change correspond ? 
 
 14.' Compare the rate of change in temperature this 
 month with that for March. 
 
 15. What wind accompanies the highest temperature ? 
 The lowest ? Compare with March and December. 
 
 16. What is the greatest range in the movemeiit of the 
 barometric column ? Compare with March and Octo- 
 ber. 
 
 17. Has there been any uniformity in the barometric 
 record just before storms ?' 
 
 18. Does the movement of the barometric column cor^ 
 respond in any way to that of the thermometer ? 
 
 19. Have there been any mornings without eithe^" 
 frost or dew ? 
 
 20. Can you find any places where the ground is still 
 frozen ? 
 
 STUDIES OF SIGNAL SERVICE MAPS. 
 
 21. What isotherm crosses nearest where you live this 
 month ? Is it changing its position in either direction ? 
 
332 NATVRe: STUDY. [April 
 
 22. What isotherm crosses the Gulf States ? Compare 
 with March. 
 
 23. Compare the position of the isotherms that cross 
 the country this month, with those of the month referred 
 to above in (13). Try to explain any difference noticed. 
 
 24. Where have the Low Areas generally been formed 
 this month? Compare with March. 
 
 25. What has been the direction of the great storms ? 
 Can you notice any difference from that of preceding 
 months ? 
 
 26. Compare the temperature of the Low Area with that 
 of the High Area ; does it bear the same relation that it 
 did in preceding months? 
 
 27. In what quarter of the country has there been the 
 heaviest rainfall ? Compare with the autumn month re- 
 ferred to above in (13). 
 
 28. In what place does the heaviest rainfall occur 
 with respect to tlie Low Area ? 
 
 29. What is the uniform direction of- the wind about 
 the Low Area ? Have you found any exceptions to the 
 rule ? 
 
 30.' Do the Great Lakes appear to affect the course of 
 the storms ? Note the effect of the mountain.s, valleys, 
 and coast lines. 
 
aetronom^. 
 
 In view of the importance of the point to be enforced, 
 it will not be considered out of place here to speak spe- 
 cifically of what has been hinted at before concerning the 
 proper use of symbols and diagrams in illustrating this 
 subject. The teacher should sharply discriminate be- 
 tween the pupil^s ability to comprehend an illustration, a 
 mere device, and his power to grasp or form a concept 
 of the real thing to be taught. A pupil, pointer in hand, 
 may glibly explain a diagram on the blackboard which 
 illustrates the vartous movements of the heavenly bodies 
 and their mutual relations, without having the faintest 
 glimmer of those great educative conceptions of space, 
 time, and force, which are the true outcome of the' study 
 when properly conducted. Specific rules of procedure 
 which will suit all cases cannot be given ; it should be 
 constantly borne in mind, however, that the true ideas 
 must come from small beginnings, but, if properly started, 
 they will be of perennial growth. Something which falls 
 within the bounds of the pupil's experience should be 
 seized upon, and from it his mind, unaided, should be 
 led outward toward the source of the phenomenon to the 
 very limit of his power of thought, and then, only, may 
 a device be relied upon to safely perform its proper func- 
 tion of illustration. 
 
 r. Compare the movement of the noon shadow with 
 that of last month ; what do you notice about the rate 
 of movement ? 
 
 333 
 
534 MATURR STVDV. [April 
 
 2. With what previous month do the marks most nearly 
 coincide ? 
 
 3. How does the rate of movement correspond with 
 that of the same month ? 
 
 4. Is the rate of movement of the noon shadow increas- 
 ing or diminishing? 
 
 5. What angle do the sun's rays now make with the 
 earth ? Compare with December. 
 
 6. If the apparent path of the sun could be traced 
 across the heavens daily, what kind of a line would be 
 formed ? 
 
 7. Can you determine from a measurement of the 
 angle of the noon shadow how high the sun would ap- 
 pear to one at the North Pole ? How high would it ap- 
 pear to one on the Arctic circle at noon ? 
 
 8. Where on the globe is the longest day at this time ? 
 Explain why it is so. 
 
 9. Where is the shortest day? Are the days and 
 nights equal in length anywhere ? 
 
 10. How many degrees on the horizon has the sun 
 moved since the vernal equinox ? How many degrees 
 has it climbed the meridian in the same time ? 
 
 11. How many 'degrees has it moved on the horizon 
 since the winter solstice in December? 
 
 12. Is the rate of change in the day's length increasing 
 or diminishing ? Explain why this is so. 
 
 13. Is the increase of the day's length made by equal 
 additions morning and evening? 
 
 14. When are the variations at morning and evening 
 most nearly equal ? When are they most unequal ? 
 
 15. In what part of the year is the variation greatest 
 in the morning ? When is the variation greatest at even- 
 ing ? 
 
April] ASTRONOMY. 33S 
 
 i6. To what causes are the differences noted in (15) 
 ' due ? 
 
 17. About the middle of this month it will be floticed 
 that Mercury appears as evening star. How have the 
 earth and it changed in relation to each other since it 
 was seen as morning star ? (See Astronomy for Febru- 
 ary). 
 
 18. Additional constellations : Crater; Berenice's Hair. 
 
 Reference. Humboldt Library : No. 14, Wonders of the Heavens. 
 
(Beograpl)^. 
 
 EURO-ASIA. PRODUCTIONS. 
 
 1. Where are the greatest differences in productions 
 between the northern and southern, or eastern and west- 
 ern divisions of this great continent ? Why ? 
 
 2. What contrasts are presented in the productions 
 between those of the coast and the interior ? 
 
 3. Does the eastern or western coast differ more 
 widely from the interior in productions. Why ? 
 
 4. Are the river valleys important in their bearing 
 upon the productions ? Which ones are most important ? 
 
 5. Where is the most important grain region ? What 
 conditions favor it ? What cities lead in grain exports? 
 
 6. Is the grain region found in the same latitude in the 
 different parts of the continent ? 
 
 7. Compare the latitude of the grain districts in Euro- 
 Asia with that of North America. 
 
 8. Where are the timber regions of Euro- Asia ? What 
 varieties are to.be found ? What are the climatic condi- 
 tions found in a timber region ? 
 
 9. How does the character of the forests in the north- 
 ern latitudes differ from that of those in the southern ? 
 
 10. Compare the latitude of the northern timber-line 
 in Euro-Asia with that of North America ; how can you 
 account for the difference noticed ? 
 
 11. What differences are there between the produc- 
 
 336 
 
April] GEOGRAPHY. 337 
 
 tions of the Mediterranean countries and those of south- 
 ern Asja ? What influences combine to giv6 them some 
 similarity ? What is the difference in latitude? 
 
 12. In what regions are the fruits of the temperate 
 zone grown ? 
 
 13. Where are the vine, the olive, and fig cultivated ? 
 Compare with the same latitude of North America. To 
 what is the great contrast chiefly due ? 
 
 14. Where are the great meadow-lands of Euro- Asia ? 
 Which do these more closely resemble, those of North 
 America or South America ? 
 
 15. In which of the three continents mentioned in (14) 
 is the character of the productions mostly dependent upon 
 latitude ? 
 
 16. Compare the effects of the great mountain ranges 
 in these continents upon the' productions. 
 
 17. Locate the chief mineral regions of Euro-Asia. 
 What minerals are of most importance ? 
 
 18. What ones of value in the Ural Mountains? 
 
 19. Where are precious stones found? Where are 
 gold and silver found ? 
 
 20. Where aire the valuable iron niines ? Coal mines ? 
 Where is tin found ? 
 
 21. Does the character of the productions of a country 
 make its impress upon the people? Compare the agri- 
 culturists of Europe with those that work in mines ; 
 what differences in their character are due to their differ- 
 ent occupations? 
 
 22. Where are the most thrifty peoples of Euro-Asia 
 located-? Is their thrift due to any extent to the kind of 
 productions in their countries ? 
 
 23. What is the character of the vine-growers ? Of 
 the grain-raisers ? 
 
338 NATURE STUDY. [April 
 
 24. Is the intelligence of a people in any great measure 
 dependent upon the productions of the countries in which 
 they live? Illustrate the point in Euro-Asia. 
 
 25. Are the conditions of the present tending to reduce 
 or increase the importance of the relation which- exists 
 between the character of a people and the productions of 
 their country ? 
 
' Last month we considered the geological importance 
 of an organism which has done, in connection with other 
 creatures of the same character, a work almost inconceiv- 
 ably vast in making the earth's crust what it is. This 
 month we must consider the work of another class of 
 organisms, which is of less extent, perhaps, but hardly less 
 interesting. The study relates to the work that plants are 
 doing, and have done, when under certain conditions, at 
 building on the earth's surface. The work should be 
 preceded by a visit to a swamp, and as close a study of 
 it as the age and experience of the pupils will warrant. 
 
 1. What are some of the conditions which have caused 
 the swamp ? 
 
 2. Is it the result of a stream or a lake ? Is it being 
 filled by sediment that is washed in from the adjacent 
 land? 
 
 3. Examine some of the mud ; what is its color ? 
 Does it consist of sand grains ? 
 
 4. Is it like clay mud found in drier places in times of 
 wet weather ? Dry some of it, and compare with clay 
 and sand. 
 
 5. Using a pole as a probe, can you tell how deep it is ? 
 
 6. Where does the soft material come from that is not 
 washed in from adjacent higher ground ? 
 
 7. Can you find the remains of either animals or plants 
 in the mud ? Do they seem to be decaying ? 
 
 8. In some of the great bogs of the world, some marvel- 
 Qusly well preserved specimens have been found. " In 
 
 339 
 
34° NATURE STUDY. [April 
 
 1747, in an English bog, the body of a woman was found, 
 with skin, nails, and hair almost perfect, and with sandals 
 on her feet. In Ireland, under eleven feet of peat, the'body 
 of a man was found clothed in coarse hair-cloth." (Le 
 Conte.) 
 
 9. Can you tell what effect the vegetation that now 
 covers the swamp has upon it ? 
 
 10. Can you tell whether the vegetation ever differed 
 from what it now is ? Was it a swamp when the vegeta- 
 tion differed ? 
 
 11. Does the vegetable matter decay as it falls to the 
 earth. each year ? 
 
 12. When the black material of which the swamp is 
 composed is dried and ignited, will it burn ?- 
 
 13. If it burns, what does this show its history to be ? 
 
 14. Peat swamps are found in Irelarid, France, and 
 many other parts of middle and northern Europe. They 
 are much more abundant in the north than in the south. 
 They are rarely found south of 36° latitude. 
 
 15. The Great Dismal Swamp of Virginia is an ex- 
 ception. It is forty miles in length, north and south, 
 and twenty-five miles wide. There is a depth of fifteen 
 feet of vegetable matter. 
 
 16. Why is it that peat bogs are much more common in 
 the north than in the south ? 
 
 17. What kind of climate would be best for them ? 
 Why ? The peat formation in the Dismal Swamp is 
 rendered possible by the large trees with dense foliage 
 which grow there. Can you see a reason ? 
 
 18. What happens to vegetation that falls to ground 
 in the southern or very warm countries ? 
 
 19. Can you picture to yourself how it would be possible 
 for a peat bog to be transformed into a coal bed ? 
 
 7,0, Where is peat now used largely as fuel ? 
 
fiDineralool?. 
 
 Pupils are always greatly interested in making those 
 tests which produce some mysterious changes in the sub- 
 stance used. It is often not possible for them to under- 
 stand what those changes really are (who does under- 
 stand them ?), but such work is stimulative of thought 
 and inquiry, and is perfectly legitimate with those pupils 
 who can handle the material and apparatus themselves. 
 Through this kind of work will be acquired the habit of 
 carefully examining such things as come under their 
 notice, and also the skill necessary to enable them to do 
 so. The outcome of the habit is self-reliance, a factor of 
 inestimable worth in the make-up of character. The 
 apparatus needed for certain instructive flame-tests is so 
 simple that no pupil, even in remote country districts, 
 need be without the means of informing himself of im- 
 portant and interesting properties of all the different 
 minerals in his locality. Directions for making an 
 alcohol lamp are given under Chemistry for November. 
 
 A small pair of sharp-pointed steel forceps or tweezers, 
 such as are in common use by jewelers, will be useful, 
 it may be said, a necessity. In addition, there should 
 be provided two pieces of hard glass tubing, each 
 about three inches long, one closed at one end and the 
 other open at both ends. A few small pieces of red and 
 blue litmus paper will also reveal interesting facts about 
 some minerals when heated in the tubes. Enough may 
 
 341 
 
342 NATURE STUDY. [April 
 
 be obtained of any dfuggist, for five cents, to supply a 
 whole class. 
 
 1. Select from the minerals, collected by the pupils, a 
 number of different kinds, and break off some very small 
 pieces or splinters of each. 
 
 2. Take up one of these with the forceps — ^it should not 
 be larger than a pin's head — and hold it steadily in the 
 tip of the flame just below the bright part. Does it 
 melt ? Look sharply at the thin edges of the points of 
 the piece. When melted thus it is said to be easily fusible. 
 When minerals cannot be melted, they are infusible. 
 Some minerals, here infusible, might fuse in a flame with 
 blowpipe. 
 
 3. In the same way hold a small lump of salt. Does 
 it melt ? What becomes of it ? Minerals which fly to 
 pieces when heated are .said to decrepitate. 
 
 4. Can you detect any odor when the mineral is 
 heated ? Heat a small piece of sulphur and note the 
 odor. Note the odor from a srnall piece of soft 
 coal. 
 
 5. Some minerals color the flame. To get this color, 
 hold the mineral in the edge of the blue part of the 
 flame. The wick should be new and clean and the 
 alcohol pure, so that the flames may be as nearly colorless 
 as possible. 
 
 6. Hold a small piece of salt in the flame ; what is the 
 color ? This is called the sodium flame. 
 
 7. Try a small piece of calcite in the same way ; what 
 difference in tinge is noticeable ? 
 
 8. Try a piece of copper wire. What is the color ? 
 Dip the wire intojiydrochloric acid and hold in the flame. 
 What is the color ? 
 
 9. Take a small piece of potassium chlorate that was 
 
April] MINERALOGY. 343 
 
 used in making oxygen. (See December.) Wliat tinge 
 has the flame ? This is the potassium flame. 
 
 10. Place a very small amount of the powdered 
 rnineral, not more than half the size of a pea, in the 
 closed tube and heat gradually over the lamp ; watch 
 closely ^;he sides of the tube. Are there any drops of 
 moisture ? 
 
 11. Try a small amount of marble ; does it undergo 
 any change ? 
 
 12. Try a little powdered gypsum ; what change 
 noticed ? 
 
 13. Separate those minerals which contain water from 
 those which do not have it, as shown by this test. 
 
 14. Try a little sulphur in the tube ; what collects on 
 the sides of the tube ? 
 
 15. Use a little powdered iron pyrites ; note the sides 
 of the tube. Is there any odor ? 
 
 16. The substance formed on the sides of the tube is 
 called a sublimate. This process is called sublimation. 
 Compare with distillation. 
 
 17. Repeat the experiment, using the open tube. 
 Place the mineral some distance within the tube and hold 
 it but slightly inclined, so that the mineral will not slide 
 out. 
 
 18. Note the odor. Does sublimation take place as 
 before ? 
 
 19. Moisten a small slip of the litmus paper in clean 
 water and hold in the tube so that the vapors will strike 
 it. Which color is affected ? 
 
 20. To get the meaning of this, moisten each kind 
 with a little acid ; which color is affected ? Try, in the 
 same way, moistening each with a little ammonia. The 
 blue litmus paper is thus a test for acids, being changed 
 
344 N-A TURE STUD Y. [April 
 
 to red by them, and the red is a test for alkaline sub- 
 stances, the color being changed to blue by them. 
 
 21. Do all of your minerals give off acid vapors ? Try 
 the above tests with quartz. 
 
 22. These exercises with minerals may be extended so 
 as to include all the specimens in their collections. 
 
Some one has said that the child is a natural born sav- 
 age. Whether this savagery is due to inherited traits 
 that root far back in his remote ancestry, or to a gross 
 ignorance concerning the creatures about him, the result 
 of criminal neglect on the part of his teachers, is a ques- 
 tion that will bear discussion. Both sides may, perhaps, 
 contain a half-truth. Certaiii it is, however, that as the 
 child learns more and more of the habits of the living 
 things about him he becomes less cruel in his treatment 
 of them. Cruelty to animals and their wanton destruc- 
 tion is the concrete, as well as the most pronounced, 
 hateful, and brainless expression of that worst of all 
 traits of human character — selfishness. The teacher of 
 natural science fails in a most important function of his 
 work if the pupils that pass from under his care are not 
 ever afterward entirely humane toward the lowly members 
 of creation. If the teaching of elementary science in 
 the public schools could accomplish no other end beyond 
 that of making the children more thoughtful, tender, 
 and considerate toward the brute creation, it would be 
 well worth all the time and attention its most enthusiastic 
 advocates claim for it. 
 
 The robbing of birds' nests by the " bad boys " of 
 every community is a pastime that is as common as it is, 
 unfortunately, destructive. The natural timidity of the 
 birds is a thousandfold increased, and many a bush, tree, 
 or thicket that might become the abode of a family of 
 
346 NA TURE STUD Y [May 
 
 feathered songsters is rendered silent, tenantless, and 
 dreary by the untimely raids of juvenile vandals. It is 
 only because the misgivings, which naturally arise about 
 the propriety of giving such directions in an elementary 
 work, are outweighed by the hope that the teacher's con- 
 stant supervision aVid humane judgment will at all times 
 prevail in properly directing the pupils, that instructions 
 are here given as to the collection and preservation 'of 
 nests and eggs. Whatever collections are made by the 
 pupils should be for the school of which they are mem- 
 bers. Taking nests and eggs for mere pastime or by 
 individuals who have neither the means nor the intention 
 of permanently preserving them should not be permitted 
 at all. The birds can well afford to spare a nest and a 
 set of eggs of each kind for the school, and in the end 
 they will be the gainers through the greater consideration 
 in treatment which they will receive at the hands of the 
 pupils who thus learn about them. 
 
 No nest or eggs should be taken unless ^it is certainly 
 known to what kind of bird they belong. Nests near 
 dwellings and schools should not under any circumstances 
 be disturbed, as they afford easy opportunity for the 
 study of the habits of the birds. A nest should not be 
 taken until it is certain that the full set of eggs has 
 been laid. To preserve a nest, remove it carefully, with- 
 out displacing any of the materials, and sew it through 
 and through with a very fine wire. This may be done so 
 that the wire will not be visible except on very close ex- 
 amination, and yet all the parts will be held firmly to- 
 gether. Do not draw the wire tightly enough to change 
 the shape of the nest. Make a stand as follows : Take five 
 pieces of annealed iron wire, about six or eight inches long 
 and about fifteen gauge. Twist them together for three 
 
May] ZOdLOGY. 347 
 
 or four inches from one end to make a stem, and spread 
 the wires ap^rt at the other end so as to form in basket- 
 like support to receive the nest. Make a hole of suit- 
 able size in a block one inch thick and four inches square, 
 and insert the end of the stem formed by twisting the 
 wires as directed above. Put the nest in position and 
 bend the wirqs about it so as to hold it in place. Attach 
 a label bearing the name, date, location, and other data 
 regarding the nest. Nests thus mounted will bear a great 
 deal of handling in class use. 
 
 To preserve the eggs, they must be blown. Break a 
 large sized knitting needle in two in its thickest part and 
 file the thick end down to a tapering three-sided point. 
 This makes a serviceable drill. Draw a small glass tube 
 to a fine point, and at about an inch from the pointed 
 end bend it to nearly a right angle. In the side of the 
 egg, drill a single hole, twirling the drill rapidly and 
 lightly between the thumb and forefinger, the size being 
 dependent upon the size and freshness of the egg. 
 Place the tip of the blow-pipe described above, at the 
 entrance of the opening (it need not be thrust into the 
 egg), and, by blowing gently, the contents will be forced 
 out. Fill the mouth with clean water, and by means of 
 the blow-pipe inject it into the egg and thoroughly rinse 
 it out. Do not wet or smear the outside, and do not 
 wash off the mud or any other matter adhering to the 
 outside of the shell when the egg was found. After 
 rinsing until the water comes out clear, inject, by means 
 of a small glass syringe (a medicine dropper will do), a 
 httle water in which a very little corrosive sublimate (a 
 deadly poison ! !) has been dissolved. After draining 
 it out, the eggs may be put away in the nests or trays 
 prepared for them. When the eggs contain embryos, as 
 
348 NATURE STUDY. [May 
 
 is frequently the case, a large hole must be drilled and 
 the contents be cut to pieces with a pair of sharp 
 pointed scissors and either rinsed out or removed with a 
 hooked pin. 
 
 , If the egg is large enough, with a fine pointed pen 
 write the name of the egg on the shell with ink and also 
 number it. If too small, then use the number only. In 
 either case, record the name and number in a check 
 book, and also note the conditions under which it was 
 found. A brief history of the nest and eggs and their 
 environment is interesting, and in the end very valuable. 
 Place the number and name on the same side through 
 which the hole is drilled and make it the under side as 
 the egg lies in the tray. 
 
 BIRDS' NESTS AND EGGS. 
 
 1. Make a study of the materials found in different 
 birds' nests ; what points of similarity and contrast do 
 you find between those that build on the ground and those 
 that build in trees ? 
 
 2. Which class of birds build the more elaborate nests, 
 the ground or arboreal ? 
 
 3. Where are the materials for the ground nests ob- 
 tained ? What objects does the bird appear to have in 
 view in selecting a site ? 
 
 4. Are the materials uriiformly of the same kind in 
 the arboreal nests ? 
 
 S- By what devices are different nests held in place ? 
 Are they the same in nests of the same kind of bird in 
 different places ? ■ 
 
 6. Where is the material obtained ? Do the birds 
 prepareit in any way before building it into the nest ? 
 
May] ZOOLOGY. 349 
 
 7. How do they carry the materials ? Do both sexes 
 engage in the work ? 
 
 8. Note and compare the different locations selected. 
 Can you see the advantages of each ? 
 
 9. Do the birds display intelligence in building their 
 nests, or can you account for all you see through inherited 
 instinct ? What would be a fair test as to whether blind 
 instinct or intelligence guides the bird ? 
 
 10. Can you find any odd or new adaptations to the 
 surrounding conditions in any of the nests ? 
 
 11. What are the devices for concealment, natural and 
 artificial ? 
 
 12. Is there any correspondence between the color of 
 the bird and the character of the nest ? 
 
 13. Compare the nests of the brightly colored birds with 
 ^those that are dull colored. Is there any attempt made 
 
 to sirhulate the surroundings in any way ? 
 
 14. At what time in the day are the eggs laid ? Aawhat 
 intervals ? 
 
 15. Can you see any reason for the coloring and pecu- 
 liar marking of some of the eggs ? Can you see why some 
 eggs are pure white ? 
 
 16. Is the number of eggs laid uniform with the same 
 kinds of birds ? 
 
 17. Note the time when the female begins to sit ; what 
 does the male do during this period? 
 
 18. How long before the young birds appear? Note 
 the date. 
 
 PARTS OF AN EGG, AND THE EMBRYO. 
 
 (Use a hen's egg.) 
 Some teachers will have opportunity at this point to 
 suggest and conduct a series of most interesting observa- 
 
3S-0 NATURE STUDY. [May 
 
 tions on the incubation of the hen's egg. Among the 
 pupils there will doubtless be some who are -the owners 
 of a flock of chickens. If so, it is not difficult to find 
 one or more hens that are willing to do their part of the 
 experiment by sitting upon a nest of eggs. Start with 
 about twelve eggs in the nest and replace those taken out 
 until the total number reaches twenty-one or twenty-two. 
 Mark each new egg put into the nest with the date so that 
 they may be removed in proper succession. When the 
 egg is removed, always keep that side uppermost which 
 was so in the nest. With a knife point or pin puncture 
 the large end. Can you see why this is done ? Then 
 tap lightly on the upper side of the shell until enough is 
 broken to make, when it is removed, a hole about the 
 size of a penny. Carefully remove the membranes, and 
 look for any changes that may have taken place within. 
 If a compound microscope be at hand, there may be seen, 
 within a few hours, most wonderful evidence of a new life 
 that has just begun. (See Zoology for March.) Even 
 to the unaided eye the changes are very soon well 
 marked. Examine an egg every twenty-four hours, and 
 note the progress- of development. It is well to remove 
 the embryo chick and preserve the series for further 
 study. To do this, immerse the egg, the opening upper- 
 most, in a vessel of strong salt water. With fine-pointed 
 scissors cut around the area, plainly visible, occupied by 
 the embryo chick and let it float out of the shell. Catch 
 it on a bit of cork or smooth soft wood and keep it 
 spread with pins. Sink this in weak alcohol. As the 
 development proceeds, less trouble will be experienced 
 in removing the embryo. Small wide-mouthed ointment 
 bottles are excellent receptacles in which to preserve the 
 specimens. Each bottle should have a label bearing the 
 
May] ZOOlOGY. 35 1 
 
 date when the embryo was removed and its age in 
 days. 
 
 1. Note the general shape and size ; what is the 
 ratio of the length to the breadth ? 
 
 2. Carefully remove the shell from one side ; how many 
 linings inside of it ? 
 
 3. Note the clear white called thealbumen. Also the 
 yellowish center, called the yelk. 
 
 4. Observe the small white spot on the upper side. This 
 is called the germjnal spot-. Observe this spot when the 
 process of hatching begins. Did you ever see it anywhere 
 except on lop of the egg? What advantage in this ? 
 
 5. Remove the shell from a hard boiled egg ; do the 
 contents entirely fill the shell ? What reason can you as- 
 sign ? 
 
 6. What is the very first evidence of life in the egg ? 
 In what length of time did it appear ? 
 
 7. Can you -find any evidence of internal organs? 
 What ones appear to be the most necessary ? 
 
 8. Which appears first, the outline of lire bod}', the 
 skeleton, or the internal organs ? 
 
 9. Where does the nourishment necessary for growth 
 come from ? Does the embryo chick eat ? How does it 
 get its food ? Does it need air ? Does it breathe? 
 
 10. How soon can you notice the formation of any 
 external organs ? What are they ? Which part of the 
 iody is most conspicuous ? 
 
 11. Notice very carefully the first appearance of the 
 legs and wings ; can you observe any differences ? 
 
 12. How soon do bodily movements begin ? 
 
 13. When do feathers first appear ? In what parts of 
 the body are they found ? How are they arranged ? 
 
 14. What becomes of the contents of the shell ? 
 
352 NATURE STUDY. [May 
 
 15. Why is it that the chick has no use for its beak 
 while developing in the shell ? Does it use its stomach ? 
 Why? 
 
 16. What is the first use it makes of its beak ? 
 
 17. After what length of time does it leave the shell of 
 its own accord ? 
 
 18. What changes take place in its mode of living 
 when it leaves the shell ? 
 
 19. Compare its feathers with those of the mature 
 bird ; do the feathers themselves change ? 
 
 20. Compare the new-born chick with new-born 
 animals of other kinds in vigor, intelligence, and self- 
 dependence. 
 
 THE CRAWFISH. 
 
 1. Collect some crawfish and place them in an aquarium 
 or jar of water for daily observation. 
 
 2. Note the character of the places where they are 
 found ; is the water clear or muddy, still or running ? 
 
 3. How many ways have they of moving. Contrast 
 these ways. Study the flexible part of the body ; it is 
 called the abdomen. Make a drawing of it. 
 
 4. What is the chief means of propulsion in swimming ? 
 Compare the parts and form of the tail-fin during the 
 stroke with that during the return. By what contrivances 
 is the resistance reduced during the latter movement ? 
 
 5. Do the legs perform any function in swimming ? 
 What is their position when it swims ? 
 
 6. Study how the animal walks ; are all the limbs used 
 in performing this movement ? 
 
 7. Can you see the use of the short limbs under the 
 hinder part of the body ? These are called sunmmerets. 
 
 8. Can the animal see where he is going when swimming 
 tail foremost ? What peculiarity do you notice about 
 
May] ZOdLOGY. 353 
 
 the eyes ? Examine the eye under a lens ? Is it sensitive 
 to the touch ? 
 
 g. By what means does he move his eyes ? 
 
 10. What is the food of the crawfish ? How does 
 he seize it ? 
 
 11. How do his prehensile organs differ from those 
 used most in walking ? 
 
 12. What advantage do you see in the great number 
 of joints ? How do we manage to execute even a greater 
 variety of movements with fewer joints ? 
 
 13. Note the different parts concerned in bringing the 
 food to his jaws. Is the food cut, crushed, or ground by 
 the jaws ? What can you see of the movements ? 
 
 14. How does the crawfish breathe ? Does it come to 
 the surface of the water for air ? 
 
 15. Lift slightly the shell-like covering of the forward 
 end of the body by taking hold of its edges ; note the 
 little brush-like gills lying close to the side of the body. 
 
 16. Can you discover the means by which fresh water 
 is continually furnished to the gills ? Put the animal in- 
 to a shallow 'pan of water and watch carefully with this 
 in view. 
 
 17. Which way does the current of water flow ? 
 
 18. Can the crawfish live when removed from the water ? 
 Why is this ? ^yhy can we not live long if placed under 
 water ? ^ 
 
 19. Has the crawfish the sense of touch ? By using 
 a pencil or any other means find the organs of feeling. 
 
 20. Has it the sense of hearing ? Do not try to answer 
 this question until you have made a proper test. In- 
 vent some way by which a test may be applied. Can 
 you locate his ears ? ^ 
 
 21. Try to find a crawfish with eggs or young ones at- 
 
354 NATURE STUDY. [May 
 
 tached. Tf one with the eggs be found, note the move- 
 ments of the swimmerets. Why is this ? 
 
 22. How does a crawfish fight or defend himself ? If 
 any' should have a limb torn off in combat, put it in a 
 small tank by itself and observe what takes place in a few 
 weeks. 
 
 23. How is it possible for a crawfish to grow, since the 
 stiff, hard covering is on the outside of the body ? Have 
 you any proof that the shell is shed sometimes ? 
 
 24. How many distinct things are done by the various 
 appendages of the crawfish ? How many are devoted to 
 each particular kind of work ? 
 
 25. The following synopsis of the external characters 
 is appended to assist the teacher : 
 
 Cephalothorax ; the anterior inflexible part of the 
 body. Note its covering, the carapace, and its pro- 
 jecting spine in front, the rostrum. 
 
 Abdomen ; posterior flexible part of the body. 
 
 Eye-stalks ; appendages carrying the eyes. 
 
 Antennules ; pair of small feelers. 
 
 Antenn3e ; pair of large feelers. 
 
 'Mandibles ; jaws. 
 
 Maxillse ; two pairs next behind mandibles. 
 
 Maxillipedes ; three pairs next behind maxillae. 
 
 Great chelae ; largest claws, one pair. 
 
 Legs ; remaining pairs on the cephalothorax. 
 
 Swimmerets ; abdominal appendages. 
 
 Telson ; middle piece of tail fin. Compare it with 
 the other abdominal segments. 
 
 SEEING. 
 
 I. Try reading from a book, standing in the follow- 
 ing different positions : Facing the light, with the back 
 
May] ZodLOGY. 3S5 
 
 to it, and with it at one side. Which enables ycu to see 
 most clearly ? Try to give a reason. (Recall lessons in 
 Physics for March.) 
 
 2. Try to read holding the book at different distances 
 from the eye ; what is the best distance for you ? If you 
 are compelled to hold this book at much less than fifteen 
 inches you are probably near-sighted. 
 
 '3. Can you see near and distant objects distinctly at 
 the same time ? Look at the window sash and then at some 
 object beyond. Can you account for the fact that a little 
 time intervenes before the latter becomes distinct ? Why 
 is it bad for the eyes to read while on a vehicle in mo- 
 tion ? 
 
 4. What is the effect on one's vision to pass from a light 
 room to a dark one ? From a dark one to a light one ? 
 To understand this, stand facing a strong light. Hold a 
 mirror to one side toward a dark wall or surface. Sud- 
 denly turn and look into the mirror ; watch narrowly 
 the small black opening in the eye called the pupil. How 
 does it change ? 
 
 5. Turn quickly toward the light and hold the mirror 
 in front ; what change is noticed ? The curtain which 
 by contracting and relaxing alters the size of the pupil, 
 is the Yr/V. Note its color. 
 
 6. Watch the changes of the pupil in a cat's eye and 
 compare with your own. Observe the pupil in an owl's eye. 
 Can you see a reason for its great size ? 
 
 7. Can you give a reason, from what you have seen, 
 why one should have a steady light and not a flickering 
 one ? What precaution would you suggest when going from 
 a dark room to a brilliantly lighted one ? 
 
 8. Why are objects less distinct at first when there is a 
 sudden change in the intensity of the light ? 
 
35^ NATURE STUDY. [May 
 
 9. Of what use are the eyebrows ? Of the eyelashes ? 
 
 10. Why do not the eyelashes interlock when we wink ? 
 Can you see a good reason for winking ? Can you stop 
 winking if you so will it ? 
 
 II.. Examine a cat's eye when she winks. Close it 
 quietly with the hand and allow it to open slowly ; do you 
 notice anything different from your own eye ? Examine 
 your eye carefully! , 
 
 12. Examine the eyes of other animals for the same 
 thing ; the dog, the frog, the bird, the turtle, for example. 
 
 13. Can you see why we shed tears when a cinder gets 
 into the eye ? Why do we do it when hurt severely in any 
 part of the body ? Why, when we feel extremely sad? 
 
 14. What becomes of the moisture in the eyes under 
 ordinary circumstances ? Standing before a mirror, pull 
 the lower lids out slightly and look for a hole on the small 
 elevation at the inner end ; this is the opening into a tube 
 which leads to the nose. Can you find a similar opening 
 in the upper lid ? Through this tube the water is drained 
 off as fast as secreted under usual conditions. The tear 
 gland is situated above the eyeball, about midway between 
 the outer angle of the eye and the middle of the bony arch. 
 
 15. Note the thickened but flexible edges of the lids ; 
 they are kept smooth by oil, which is poured out at the 
 roots of the lashes. Sometimes this is in such quantities 
 that the eyes are glued together in the morning ; if so, 
 slightly moisten the edges with saliva. To prevent this, 
 wash the eyes well with warm water, and then bathe freely 
 with cold water before retiring. Use them less at night. 
 
May is a month of flowers. At no season of the year 
 do they seem so beautiful and so fresh as now. Where 
 a few weeks ago there was naught but the bare earth or 
 brown leaves, the relics of a past season, the magic of the 
 sunshine has now brought forth the delicate blossoms as 
 the harbingers of a new life. Botany, in the past, has 
 meant largely a rending to pieces of these flowers in an. 
 endeavor to find their name by means of an artificially ar- 
 ' ranged key. The key has its place and is useful, but it is 
 not designed for children or beginners of any age. It is 
 not likely to lead to an intelligent study of plant life. To 
 secure this, much attention should be given to the habits 
 of plants — for plants as well as animals have habits, one 
 is tempted to say, likes and dislikes^ — and it is through 
 these that easy entrance is made to the study. The flower, 
 ■however,ds but one part of a plant, and its study should 
 not be separated from the study of the plant as a whole. 
 
 Since children are so universally attracted by flowers 
 almost from the dawn of existence, it is frequently, a 
 matter of great astonishrnent to teachers to find how dull 
 a subject the study of the flower sometimes becomes to 
 their pupils. It must ever be kept in mind that children 
 are most deeply interested in objects through their func- 
 tions. Now the only function which the child can see 
 for the flower is to make woodland and meadow beautiful 
 for his own pleasure ; and since it can perform this func- 
 tion only in its entirety, he cannot be expected to en- 
 
 357 
 
3S8 NATURE STUDY. [May 
 
 thusiastically pick it to pieces for the purpose of study. 
 Whether the flower has five petals or ten stamens or a 
 compound pistil is a matter of no consequence to him 
 whatever ; and in the early stages of Observation, there- 
 fore, he should not be troubled with such things. But 
 instead, let him gather as many as possible, and drink in 
 their separate and combined beauties, and then project 
 the treasures of his soul, by means of brush and pencil, 
 until his firm and loving companionship with them' is 
 fully established. It is this growing bond of union be- 
 tween child and flower, alone, which can later lead to 
 deeper study that is honest in its purpose, intelligent in 
 its character, and fruitful in its results. 
 
 The classes should in all cases, where practicable, visit 
 the flowers in their native haunts. The younger pupils 
 may gather all within their reach and the more advanced 
 may be limited more or less to those of a particular kind 
 or to those growing in a certain prescribed area of pecu- 
 liar conditions. In all cases attention should be directed 
 to the relation of the surroundings to the plant and its 
 adaptation to its environment. 
 
 1. "VVhy is it that some plants can blossom so early in- 
 the season and others must wait until fall ? In trying to 
 answer this, ^examine, if possible, such plants as Spring 
 Beauty, Hepatica or Liver-leaf, Dutchman's Breeches, 
 Bloodroot, Dentaria Thoorotwort, and Trillium. 
 
 2. Have any of the seeds which you planted last month 
 ' produced flowers ? 
 
 3. Have any of the flowering plants mentioned above 
 come from the seed this spring ? 1 
 
 4. What advantage do such plants have over others in 
 the spring ? 
 
 5. What differences have you observed among those 
 
May] BOTANY. 359 
 
 mentioned in (i) ? Compare the Hepatica with the 
 Spring Beauty. 
 
 6. Do you find them growing in exactly the same 
 locations ? 
 
 7. What appears to be thQ favorite place of the 
 Hepatica ? Of the Spring Beauty ? 
 
 8. Do you find one growing in any location where the 
 other is not to be found ? Examine wet, dry, cool, warm, 
 wooded, and open places ? 
 
 9. In what respects is the Hepatica adapted to wood- 
 land ? Is it equally well adapted to open places ? Why ? 
 
 10. Can you see why the Hepatica can bloom even 
 earlier than the Spring Beauty ? 
 
 1 1. What do the early flowering plants do the remainder 
 of the season ? 
 
 12. How many different arrangements of the flowers 
 on the plants have you observed ? The. arrangement of 
 the flowers is called the inflorescence of the plant. 
 
 13. Compare the inflorescence of the plants mentioned 
 above in (i) ; which ones are clustered ? Which are 
 single ? The latter are said to have solitary inflorescence. 
 
 14. Where are the oldest flowers in the clusters ? 
 The youngest ? When the flowers open from the outside 
 of the cluster inward or from below upward, the inflor- 
 escence is centripetal or indeterminate. When the reverse 
 is true it is centrifugal or determinate. 
 
 15. What is the most common color of flowers that you 
 find ? Which color is least common ? Can you see any 
 reason for this ? 
 
 16. Can you see any advantage to the plant in the 
 color of its flowers ? Do the flowers remain open day 
 and night ? Are there any that bloom only at night ? 
 Are there any that bloom only during the day ? 
 
360 NATURE STUDY. [May 
 
 17. Can you find any that bloom for a day only ? 
 
 18. Do any of the flowers that you have found have 
 odor ? Where is this located ? 
 
 19. Why do the bee and other insects visit flowers? 
 Where are the sweets (nectar) stowed away ? To answer 
 this, watch an insect very closely and taste the different 
 parts of the flower. Where does the odor come from ? 
 
 20. How does the insect know where to look ? 
 
 21. Why is it that the flower so kindly feeds the insect? 
 
 22. Do the insects carry away anything besides nectar 
 from the flower ? How do they get it ? 
 
 23. How many different sets of parts do you find to a 
 flower, the Spring Beauty, for example ? 
 
 24. Each set is called a whorl, even though it consists 
 of but a single part. In the Spring Beauty, for instance, 
 is the single central part called the pistil. Surrounding 
 this is a whorl or circle of stamens ; next outside is the 
 delicately colored corolla, and still outside of all is the 
 calyx. 
 
 25. Are there four whorls present in all the flowers that 
 you have found ? Which whorls have you found absent ? 
 When any one or more of the whorls is absent, the flower 
 is incomplete. When all are present it is complete. 
 
 26. Can you see any use for the pistil? Note its 
 enlarged basal part called the ovary; what does it 
 contain ? The undeveloped young seeds are called ovules. 
 
 27. Note the slender stalk on. top of the ovary called 
 the style and the three-lobed tip called the stigma. Is 
 there any evidence of a whorl of parts united in the pistil 
 of the Spring Beauty? 
 
 28. Examine the stigmas of different flowers very 
 carefully ; do you find anything adhering to them ? Use 
 a magnifier. 
 
May] BOTANY. 361 
 
 29. Shake a flower over a clean piece of papar ; 
 where does the dust come from ? The stamens have two 
 parts, usually, the sXtn&tr filament and the enlarged kftob- 
 like anther. The yellowish powder from the anther is the 
 pollen. 
 
 30. The parts of the corolla are called /«/a/j. Are they 
 present in all flowers that you have seen ? Of what use 
 to the flower is the corolla ? 
 
 31. The calyx, as seen in the Spring Beauty, is com- 
 posed of parts called sepals. What appears to be their 
 use? 
 
 32. The stamens and pistil together are called the 
 essential organs of the flower. Can you see why the pistil 
 should be classed as an essential organ ? 
 
 33. Taken together, the corolla and calyx are called the 
 perianth. When the perianth consists of colored parts 
 only, it is usually the calyx. The whorls of the perianth 
 are sometimes called \hi: floral envelopes. Why? 
 
 34. Note the whorl of green leaves just at the base of 
 the flower in the Hepatica. Is it a calyx ? Compare with 
 the Spring Beauty. 
 
 35. Note the position of the flowers on different plants. 
 Can you understand why some droop while others are 
 upright ? Does the position seem to affect the growth of 
 any of the whorls ? 
 
 36. Compare the stamens and pistil in drooping 
 flowers with' those habitually erect. Can you find any 
 
 , prevailing contrast ? 
 
 37. Compare these with flowers that project sidewise 
 froni the stem ? Is there any constant difference in the 
 shapes of flowers that grow in different positions ? Can 
 you see any reason for it ? 
 
 38. Flowers in which the different parts of the same 
 
362 NATURE STUDY. ^ [May 
 
 wlaorl are not of the same size or shape are said to be 
 irregular. Can you see anything in the growth of the 
 plant which would tend to produce irregular flowers ? 
 
 39. Carefully compare the number of parts in the dif- 
 ferent whorls of the flowers ; where there is not the same 
 number of parts in each whorl, the flower is unsym- 
 metrical. 
 
 40. Can you find any ruling number in the parts of 
 the flower? What is the most common number? The 
 next prevailing number ? 
 
 41. How are the parts of one whorl arranged with 
 respect to the adjacent whorls ? Are all flowers alike in 
 this particular ? 
 
 42. Are the petals separate in all the flowers you have 
 examined ? When separate, they are said to be distinct 
 and the corolla is pMypetalous. When united entirely or 
 in part they are said to cohere, and the corolla 'n gamopetal- 
 ous. 
 
 43. Note in the same way the calyx ; it is either 
 polysepalous (distinct sepals) or gamosepalous (cohering 
 sepals). 
 
 44. Can you find a flower when one whorl grows fast to 
 another? It is then said to be adnate. Examine apple 
 or cherry blossoms. 
 
 BUDS. 
 
 1. Procure a branch on which the buds are unfolding. 
 Do all of its parts develop into leaves ? 
 
 2. What do you find inside the bud? Cut one of the 
 buds lengthwise and another crosswise and examine the 
 arrangement of the parts inside. Make drawings to 
 show it. 
 
 3. Are the small leaves all packed away in the bud 
 
May] BOTANY. 363 
 
 in the same manner ? Pick a bud to pieces and notice 
 how each leaf is wrapped or folded. The folding of the 
 leaf in the bud is called the vernation of the leaf. Is 
 there any relation noticeable between the shape of a leaf 
 and its vernation ? 
 
 4. As the young branch grows, can you see any indica- 
 tions of new buds being formed on it ? In what positions 
 do they grow ? 
 
 5. Is there any growth in the last year's branch which 
 is now putting forth the new ones ? 
 
 6. What is the difference in the texture and general 
 appearance between the new and the old branches ? 
 
 7. On some rapidly growing branch make some 
 measurements and determine the daily rate of growth. 
 A lilac, poplar, or willow will be a good one to ob- 
 serve. 
 
 8. Can you tell where the new material is depiosited 
 which elongates the branch ? 
 
 9. Watch closely the time when the twigs on the tree 
 selected for study in the spring stop growing ;^has the 
 tree any work to do during the remainder of the sekson 
 after the growth of the twig stops? 
 
 10. On what part of the tree are the strongest growths 
 produced ? Can you give a reason for it ? 
 
 FERNS. 
 
 For beauty and gracefulness of appearance the ferns 
 rival any of the flowering plants. The field lesson will 
 reveal the fact that they are as attractive to the pupils as 
 any of their more pretentious neighbors, and they should, 
 therefore, receive their share of attention. 
 
 I. Can you find anything about the fern that resem- 
 bles a flower ? 
 
3^4 i^ATlfRE STUDY. [May 
 
 2. Does it produce a stem as other plants do ? Ex- 
 amine the part under ground. 
 
 3. In what locations are ferns to be found ? Do they 
 seem to have anything in common with other plants in 
 the same location ? 
 
 4. Notice the small brown dots called sori (singular 
 sorus) on the back of the fern-leaf or frond. Such 
 fronds are called fertile, for it is from the fine dust-like 
 spores that come from the sori that the young ferns are 
 produced. These are much too small to be studied with 
 the unaided eye. 
 
 5. Are all the fronds fertile ? Can ysu find any ferns 
 that do not produce the sori on the back of the fronds? 
 Are they all arranged the same way when they do grow 
 on the back of the fronds ? 
 
 MOSSES. 
 
 1. In what locations do you find mosses most abun- 
 dant? How do the locations differ from those of most 
 plants ? ' 
 
 2. Do you find them growing in dry as well as moist 
 spots ? 
 
 3. Does the moss found growing upon the trunk of a 
 tree derive its nourishment from the tree ? 
 
 4. Do those which grow upon rocks, use the rock as 
 other plants use the soil ? 
 
 5. Do mosses have roots ? Do they have flowers ? 
 
 6. Can you find any moss that is sending up delicate, 
 thread-like stems sailed setm, which bear small spore- 
 cases on top ? The lid-like covering of the latter is 
 called 'Ccv^calyptra. 
 
 7. Remove the calyptra and shake the moss over a 
 clean sheet of paper. These minute dust-like bodies are 
 
May] BOTAt^V. 3^5 
 
 called spores, and from these the young plant is pro- 
 duced. 
 
 "8. Do you find any resemblance in the mosses to the 
 ferns ? To flowering plants ? What are the chief differ- 
 ences from the latter ? 
 
lC>bl2sic0. 
 
 SOUND. 
 
 In the study of sound there are many interes'ting 
 experiments which may be performed that will properly 
 open up the subject for young beginners and lead them 
 to further observation. Experiments may be per- 
 formed by the pupils which will enable them to see 
 something of the relation of sound to vibrating bodies ; 
 but it is not so easy to devise those which will show 
 directly that air is a conducting medium ; nor is it possible, 
 by actual experiment, for them to understand very clearly 
 the nature of the sound waves in it. 
 
 Initial interest in the subject may be gained by taking 
 up some sounds with which the pupils are familiar. Noth- 
 ing will more certainly assure this than some simple in- 
 strument, such as an .^olian harp, which may be con- 
 structed by the pupils as follows : Take a dry pine board, 
 about six or eight inches wide by one-half inch in thick- 
 ness, and cut it so that it will slip easily into the window 
 when the sash is raised. Drive ahout ten tacks or small 
 nails in each end, opposite each other, letting t"he heads 
 project about one-eighth of an inch. If small screw eyes 
 instead of nails are used in one end, the strings may be 
 keyed up or loosened as desired. Beginning at one side 
 stretch from the first nail in one end to the one opposite 
 it in the other a single silk thread, which has been well 
 
 366 
 
May] PHYSICS. 367 
 
 waxed. Then twist two threads together tightly and wax 
 them and stretch between the second pair of nails, and so 
 on increasing each cord by one thread of silk. Next, 
 make two bridges of hard wood of the same size and 
 shape. Their length should equal the width of the board, 
 and they should be about one and one-half inches wide 
 at one end and three-quarters of an inch at the other. 
 The upper edge which supports the strings should be 
 beveled to a sharp edge. Slide the bridges on their 
 sides under the strings near the middle of the board 
 and then turn them up properly and slip them along 
 toward either end of the board until the strings are all 
 quite taut. Raise the sash high enough to clear the 
 bridges and place the board in the window. A very 
 slight breeze will start the music, which will continue to 
 be produced while the wind blows, with almost infinite 
 variation. 
 
 1. What , is the cause of the sound that comes from 
 the ^olian harp ? 
 
 2. Can you discover how it is produced ? Fold a few 
 very light, narrow strips of paper half an inch long, and 
 drop them across the middle of different strings ; what 
 do you notice when the wind blows across the string ? 
 
 3. Lay a small stick of wood across the middle of the 
 strings ; what effect does it have upon the music ? 
 
 4. How are the low tones produced ? Place a stick 
 upon different sets of the strings and note the result. 
 
 5. What produces the high tones ? What is there 
 about the strings of the harp which affects the pitch of 
 the tone ? 
 
 6. What causes the loud tones ? Do loudness and 
 pitch depend upon the same thing ? 
 
 7. Why is it that sometimes very soft tones are pro- 
 
368 NATURE STUDY. [May 
 
 duced ? Are all the strings capable of producing soft 
 tones ? Test, as before, with a stick. 
 
 8. What is the difference between a low tone and a 
 soft tone ? 
 
 g. Compare a loud tone with a high tone ; may both 
 tones be produced by tlie same string ?^ 
 
 10. Can both a high tone and a low tone be produced 
 by the same string ? 
 
 11. Does the board have any influence upon the tones 
 produced ? 
 
 12. Move the bridges a little closer together ; what 
 difference in sound is noted ? To what is this due ? If 
 screw eyes are used in one end of the board, as suggested 
 above, the strings may be readily tightened with the 
 bridges in any position. 
 
 13. What effect is produced by placing the bridges 
 farther apart ? To what is the effect due ? 
 
 14. What is the best size for the window opening ? 
 Would the harp play as well in a similar opening at the 
 top of the window ? 
 
 15. Can you see a reason for using silk thread ? Why 
 should it be waxed ? 
 
 16. Can you, when out of doors, hear any sounds which 
 are produced in a way similar to the manner in which 
 they are made by the .^Eolian harp ? 
 
 17. What sounds can you distinguish that come from 
 a different cause ? 
 
 18. In the sounds that you hear about you on all sides, 
 can you distinguish those of the same varieties that were 
 produced by the ^olian harp ? 
 
 19. What produces high tones? Low tones? Can 
 you distinguish soft tones ? By what are the loud tones 
 produced ? 
 
May] PffYSICS. 3^9 
 
 20. Are there any sounds produced that are not musi- 
 cal ? What difference do you notice between musical and 
 non-musical sounds? 
 
 21. Fasten a stiff wire (a knitting needle answers the 
 purpose), eight or ten inches long upright in a vise, or 
 drive it into a board or block of wood. Pull the free end 
 to one side and suddenly let it go ; describe what takes 
 place. Make a drawing of the wire, showing its range of 
 movement. 
 
 22. For convenience, certain parts of the course tra- 
 versed by the swinging wire are named as follows : The 
 motion from one extreme position of the wire to the other 
 is called a single vibration ; from one extreme position to 
 the other and back again is a double vibration or a com- 
 plete vibration. The distance from the middle point of 
 a single vibration to either extreme is called the ampli- 
 tude of vibration. The time 'occupied in making a com- 
 plete vibration is called the /^/-zW of vibration. 
 
 23. Fasten the same wire used in (21) in the vise so that 
 but half its length shall project ; what differences do you 
 notice ? Did you secure a pure tone in the first instance ? 
 Compare with the vibrations in the second position. 
 
 24. In which position does the wire have the greater 
 period of vibration ?- This can be shown if you place two 
 wires in the vise, one double the length of the other. 
 
 25. How does changing the/m^ai' affect the tone ? 
 
 26. Cause the wire to vibrate with different ampli- 
 tudes ; how does it affect the sound ? 
 
 27. Strike one edge of a small bell with a stick or a pen- 
 cil ; hold a small cork or a bead suspended by a thread 
 so that it rests lightly against the opposite side of the 
 bell at the edge. What does the cork tell you ? 
 
 28. Strike a tuning fork against something, and while 
 
37° Mature study. [May 
 
 it is giving out a tone dip it quickly into a glass of water ; 
 what do you learn from this ? 
 
 29. Strike it again and set the end of the fork against 
 your closed teeth. Try again and hold one of the 
 prongs just touching the tip of the nose or ear. Can 
 you tell what is producing the sound in the fork. 
 
 30. Drive a small nail nearly to the head into one 
 end of the table. Stretch from it across the table a fine 
 wire or violin string. The wire may be obtained at any 
 hardware store for five cents a spool. Place under the 
 string two bridges similar to those in the harp, and from 
 its free end suspend a small pail with shot enough in it 
 to make a weight of about a half pound. 
 
 31. Pluck the string with the finger; can you follow 
 the vibration with the eye? Make a dravying of the 
 string with its attachments and mark the different things 
 described above in (22). 
 
 32. Add shot until the pail weighs one or two pounds, 
 and pkick the string again ; can you get a tone from it? 
 
 33. Add shot to the bucket until the octave is reached ; 
 how much does the pail and shot weigh ? Compare with 
 the weight with which the lower note was attained. 
 
 34. How does the increased weight affect the period of 
 vibration ? How does it affect the tone ? 
 
 35. Place a third bridge, which is a little higher than 
 either of the others, under the string, so that the part of 
 the cord on one side of it will give the octave above that 
 given by the whole cord ; what is the length of that part 
 of the cord compared with the entire string ? 
 
 36. ,How does the period of vibration of the segment 
 compare with that of the whole cord ? 
 
 37. Stretch another string, heavier than the first, by 
 the same weight ; pluck with the finger and compare with 
 
May] PHYSICS. 371 
 
 that obtained from the smaller cord. Compare its period 
 of vibration. 
 
 38. What changes could you make by which the same 
 note could be obtained from both ? 
 
 39. What things have you discovered which affect the 
 pitch of the tone ? What things affect the period of vi- 
 bration ? 
 
 40. Pkick the strings so that each will produce both 
 loud and soft tones ; can you discover what determines 
 loudness of tone ? 
 
 41. Support in a horizontal position a pane of glass, 
 about eight or ten inches square, upon a block of wood 
 half an inch square. Hold a glass rod or piece of tub- 
 ing, eighteen inches or two feet long, upright on the glass 
 plate immediately over the block. Dust a small cloth well 
 with powdered rosin, and holding the rod firmly with one 
 hand, rub the cloth up and down it with the other until 
 a sound is produced. Sprinkle fine dry sand evenly 
 over the surface of the glass and rub the rod as before. 
 
 42. What causes the sand -to move? Note the dif- 
 ferent effect upon it of the shrill and deep notes. 
 
 43. Why does it lie still along certain lines ? 
 
 44. If convenient, draw a violin bow over the edge of 
 the glass. What effects are produced by drawing it over 
 different parts ? 
 
 45. The lines along which the sand gathers are 
 called nodes. Strike a tuning fork and turn it round 
 slowly near the ear ; can you account for the intermit- 
 ting sounds ? 
 
 46. Can you see any relation between the periods 
 of silence noticed with the fork and the lines of rest on 
 the glass plate as are indicated by the sound ? 
 
 47. Hold a light piece of paper across one of the strings 
 
372 NATURE STUDY. [May 
 
 mentioned in (37) and cause it to vibrate ; can you see 
 any nodes ? 
 
 48. Why is it that when you grasp the cord, the tun- 
 ing fork, the bell, or the glass plate in any of the forego- 
 ing experiments you produce silence? 
 
 49. Recall the singing flame that was studied in 
 Chemistry for January in the experiment with hydrogen ; 
 can you account for it ? 
 
 50. Why did changing the length of the tube affect 
 the sound ? What causes the sound when you blow 
 across the mouth of a hollow key ? 
 
 57. What causes the sound in a steam whistle ? 
 
 52. Where is the sound of the human voice produced ; 
 Place the finger on the throat on "Adam's apple" and 
 prolong the sound of O, then change to the octave above ? 
 can you feel any movement? 
 
 53. Try in the same way the long sounds of all the 
 vowels ; do you notice any difference in the throat move- 
 ments in making these different sounds? 
 
 54^ The vocal sounds are produced by the air pass- 
 ing over the edges of membranes that are so stretched 
 across the larynx as to form a narrow slit-like opening. 
 The larynx, also called the voice box, is the chamber-like 
 modification of the upper end of the windpipe. The 
 membranes across it are called the voca,l cords. 
 
 55. Can you tell what probably takes place with the 
 cords when the voice is raided in pitch ? When it changes 
 from soft to loud ? 
 
 56. By what means do we mold words from the sound 
 produced by the vocal cords ? Practice many different 
 sounds until you understand how this is done. 
 
 57. Of what importance is full, perfect breathing in 
 using the voice ? 
 
May] PHYSICS. 373 
 
 58. In observing a workman using a hammer some dis- 
 tance from you, can you hear the sound as soon as you see 
 the hammer strike ? Can you hear a distant whistle as 
 soon as you see the steam issuing from it ? Why is 
 this ? 
 
 59. Sound travels about eleven hundred feet per second 
 tliroiigh air. Suppose you hear a peal of thunder ten 
 seconds after you see a flash of lightning ; how far dis- 
 tant is the cloud ? Suppose five minutes afterward you 
 hear the peal in five seconds after the flash ; how long will 
 it be before the storm reaches you ? 
 
 60. Do loud, soft, higli, and low sounds travel with equal 
 rapidity ? How does it happen that you can hear at the 
 same time the music of many different instruments play- 
 ing in a band at some distance from you ? 
 
 61. What difference can you detect between a musical 
 tone and mere noise ? Why does the tuning fork give a 
 musical tone, while a stone against which you strike it 
 makes only a noise ? 
 
 62. Can you account for an echo ? Note the condi- 
 tions which are always present when an echo is heard. 
 
 63. Hang a watch at the focus of a concave mirror ; 
 facing the mirror, but at a sufiScient distance from it for 
 the ticking to be inaudible, place another concave mirror. 
 Place a small funnel in the end of a rubber tube, and with 
 the other end of the tube held to the ear, place the funnel 
 at the focus of the second mirror. 
 
 64. Can you hold it so that the ticking of the watch 
 can be heard ? Why place the watch in the focus ? Why 
 hold the funnel in the focus of the second mirror ? Why 
 use the funnel ? Why use the rubber tube ? 
 
 65. The following table shows the number of vibrations 
 
c. 
 
 D, 
 
 E, 
 
 F, 
 
 I 
 
 1 
 
 f 
 
 f 
 
 128 
 
 144 
 
 i6o 
 
 170 
 
 B. , 
 
 c, 
 
 ¥- 
 
 2 
 
 240 
 
 256 
 
 374 NATURE STUDY. [VTay 
 
 per second of each tone in the octave below middle C, and 
 the relation of the numbers in any octave. 
 
 3 s 
 
 T -% 
 
 1.92 214 
 
 66. If there were no ear in the world, would there be 
 any sound? 
 
 67. When a bell strikes, where does the sound seem to 
 be ? Where is it really ? 
 
 68. Suppose a person were to be born deaf, and after 
 growing to adult age were suddenly to acquire the power 
 to hear ; what troubles do you think he would find in his 
 new experience ? 
 
 69. What enables us to properly locate tire source of 
 a sound ? Why cannot the child do it so accurately ? 
 
 70. Can you get an idea of sound by any means ex- 
 cept through the ear? Place a watch at first loosely 
 between the lips and then clasp it firmly between the 
 teeth ; do you notice any difference in the loudness of 
 sound ? 
 
 71. Do you see any use for the external ear ? Why do 
 we not have the power to move the ears as many other 
 animals do ? Of what advantage to them are the ear 
 movements ? What different expressions are possible 
 with them by means of their ear movements ? 
 
Cbemistr^, 
 
 FLAME. 
 
 Following the studies of the previous months upon the 
 different gases, it will now be a matter of both interest 
 and profit to study flame, with a view to seeing how it is 
 produced and of what parts it is composed. An ordinary 
 candle will serve the purpose, though a gas jet would be 
 better in some respects for part of the work. 
 
 I. Trim the tallow away from the wick, leaving it pro- 
 jecting half an inch, and light it at the tip ; what happens 
 as the flame increases in size ? 
 
 ■z. Shield it from draughts from doors or windows ; is 
 there any part visible outside the luminous cone of flame ? 
 
 To discover this, hold a sheet of paper close to the flame 
 so that the luminous part is obscured ; what do you notice 
 when you look past the edge of the paper toward the outer 
 edge of the flame ? 
 
 3. Take a short glass tube that is drawn to a point and 
 hold the large end in the blue center of the flame with 
 the pointed end upward ; can you detect any odor at the 
 tip? 
 
 4. Hold a lighted match at the tip of the tube. What 
 does this indicate ? What comes up the tube? 
 
 5. Hold a sheet of writing paper horizontally above the 
 flame and lower it steadily down in the flame to the wick 
 and quickly remove it ; what does the scorched part in- 
 dicate ? 
 
a7<5 MATURE STUDY. [May 
 
 6. Hold a small splinter across the blaze for an instant 
 and note the scorched spots ; what does their position 
 indicate concerning the different parts of the flame ? 
 
 7. Approach the flame with a splinter and notice when 
 it takes fire ; is it necessary for it to touch the luminous 
 part of the flame to ignite ? 
 
 8. Does the wick burn ? Is it the burning wick that 
 makes the large bright flame ? 
 
 9. What use can you discover for the wick ? What 
 do you find around the base of the wick ? 
 
 10. How does the oil or melted tallow reach the blaze ? 
 What change does it undergo when it reaches the blaze ? 
 See question (3) above. 
 
 11. From what you have seen can you tell which is 
 the hottest part of the flame ? The coolest ? 
 
 12. Hold a piece of a dish or glass for a moment in 
 the luminous part ; what proves to be in this part of the 
 flame ? 
 
 13. Why is the center of the flame cooler than the 
 outer part ? Why is the carbon not entirely consumed 
 in the luminous zone of the flame? 
 
 14. Lower a wire gauze over the flame ; does it burn 
 above the gauze ? 
 
 15. Hold a lighted match above the gauze ; caii you 
 produce a flame then that comes from the candle ? 
 What does that show ? Look down upon the flame 
 through the gauze. 
 
 16. Roll a little piece of gauze around a lead pencil 
 and then lower the tube over the flame ; can you explain 
 what happens ? Read about safety lamps used by 
 miners. 
 
 17. Examine, in the same way as you have the candle, 
 the flame of your alcohol lamp and note the differences. 
 
May] CHEMISTRY. 377 
 
 1 8. In the same way, also, if possible, examine a gas 
 flame. 
 
 19. Are we burning gas when we use candles ? What 
 gas is it ? What forms as a result of the burning of this 
 gas in air ? Hold a cold plate above the flame. (See 
 Chemistry for January.) 
 
 Book of Reference. Humboldt Library : No. 99 ; chapter on 
 Flame. 
 
flDeteoroIogi?. 
 
 There is no month in the year whose meteorological 
 influence is more potent for good or ill than May. Upon 
 its influences hang the prosperity and comfort, if not 
 the fate, for the rest of the season, of almost every living 
 thing, both plant and animal, in our latitude. A dry, 
 windy, warm May so thoroughly checks and stunts the 
 growth of all sprouting seedlings that hardly any amount 
 of favor for the rest of the season will enable them to 
 make good' their loss. At this time the germinating 
 plants are just trying to learn how to take their nourish- 
 ment from the soil, and they need no end of encourage- 
 ment in rains and friendly clouds that shield them from 
 the direct rays of the sun. The meteorology for the 
 month should, therefore, be studied with interest. 
 
 1. How many frosts, if any, have you noted in May ? 
 
 2. Compare May with the autumn months ; which one 
 is it most like in this respect ? ' 
 
 3. What inference can you make respecting the 
 temperature during the night of each of these two months? 
 
 4. How do the daily records of the two months com- 
 pare as to temperature ? 
 
 5. Have you noticed any change in the amount of 
 cloudiness this month ? Compare with the autumn 
 months ; with the winter months. 
 
 6. Is a cloudy May favorable or unfavorable ? 
 
 7. How do the clouds differ in character from those 
 of winter months ? Can you explain ? 
 
 378 
 
May] ME TEOROLOGY. 379 
 
 8. Compare the temperature before and after rainfall ; 
 does it vary uniformly ? 
 
 9. Do the movements of the mercurial column in the 
 barometer seem to be associated in any way with the 
 storms that have occurred ? 
 
 10. Compare the direction of the prevailing wind with 
 that for January. 
 
 1 1. What wind has be.en accompanied by rain ? What 
 one with clearing weather ? Compare with preceding 
 months. 
 
 12. Under what circumstances has dew been formed 
 this month ? Have there been any fogs ? 
 
 13. Compare the rate of change of temperature this 
 month with that of April and March. 
 
 14. What have been the extremes of temperature ? 
 Compare with the autumn months. 
 
 15. What are the extremes in the barometric record ? 
 
 STUDY OF THE SIGNAL SERVICE MAP. 
 
 16. In what quarter of the country has the Low Area 
 appeared most frequently ? 
 
 17. In which quarter has there been the heaviest rain- 
 fall? 
 
 18. Trace the isothermal line 60 degrees ; compare 
 with its course and location in April. 
 
 19. Is the isothermal 60 degrees more or less regular 
 in its course this month than last month ? 
 
 20. Compare in this particular the course of all the 
 isotherms this month with last. 
 
 21. Where are they turned most widely from the nor- 
 mal east and west line ? 
 
 22. Do the coast lines affect them now as in the 
 winter ? 
 
3?o NATURE STUDY. [May 
 
 23. Can you see any change in their course about the 
 Great Lakes ? 
 
 24. Do the great river valleys, the St. Lawrence and 
 Mississippi, seem to affect their course ? 
 
 25. What effect upon them have the Rocky and 
 Appalachian mountains? Compare with previous 
 months. 
 
astronomy. 
 
 1. How much change in the length of day and night 
 during this month ? 
 
 2. Is the rate of change increasing or diminishing ? 
 
 3. How does the rate of change compare with that of 
 last month ? 
 
 4. In what other month of the year was the rate of 
 change near what it is now ? 
 
 5. Compare the positions of the earth in its orbit during 
 these two months. 
 
 6. Try to explain, using a globe when necessary, why 
 the rate of change in the length of day and night varies 
 as it does this month. 
 
 7. Is the day gaining in length more in the evening or 
 morning ? 
 
 Can you explain this ? Compare with the amount of 
 change during the winter and fall months. 
 
 8. How is the position of the sun on the horizon, 
 morning and evening, changing ? Explain why it is so.- 
 
 9. How much has it moved on the horizon since March ? 
 How much since December? 
 
 10. Compare the rate of change in the noon shadow 
 with that of last month ; can you see why it varies ? 
 
 1 1. During what other month in the year was it nearest 
 its present position ? 
 
 12. What angle do the sun's rays make with the earth 
 this month ? Is the angle increasing or diminishing ? 
 
 38" 
 
382 NATURE STUDY. [May 
 
 13. How does the change of this angle affect things 
 upon the earth ? Does it in any way affect us ? 
 
 14. At what place or places about the middle of the 
 month on the earth is the sdn on the horizon all day ? 
 
 15. It is said that in the polar regions, before the sun 
 appears, and after it sets, there is a long period of twilight ; 
 can you explain why it is so ? Compare our twilight now 
 with that in winter ; can you see any difference ? (See 
 Physics for April.) 
 
 16. Does the twilight period increase or diminish toward 
 the equator ? Can you explain this ? 
 
 17. Have you noticed any change in the position of the 
 constellations that were observed last month ? In what 
 way can that be accounted, for ? 
 
 18. How have Jupiter and Venus changed position as 
 morning stars since last month ? Explain why this is so. 
 
 19. Can you tell how much of its orbit each has passed 
 through since it became morning star ? 
 
 20. How much of its orbit has the earth traversed since 
 then ? 
 
 21. Additional constellations : Hercules, Lyra, Arctu- 
 rus, and Northern Crown in the east in order from 
 the horizon to the meridian. 
 
(Beograpbp. 
 
 AFRICA. RELIEF, DRAINAGE, CLIMATE, AND 
 PRODUCTIONS. 
 
 It will be noticed that the structure of this continent 
 combines to some extent the physical features of both 
 the eastern and western continents. Its structure is not 
 so simple as that of either of the American continents, 
 nor is it,,as yet, nearly so well known. As before, the 
 study should be based upon good physical maps, and 
 should be accompanied by modeling and drawing. 
 
 1. Which ocean receives the largest rivers ? What is 
 the direction of the greatest highland ? 
 
 2. Compare the direction of this highland with that of 
 North America. With South America. 
 
 3. In what respect does the northern part of Africa 
 resemble the continent of Euro-Asia? 
 
 4. In what respect does the southern part resemble the 
 Americas ? 
 
 5. Where is the highest point in the principal highland ? 
 
 6. Where are the secondary highlands ? Compare their 
 position with respect to the main highland with that in 
 the other continents previously studied. 
 
 7. The navigation of the rivers is greatly hindered by 
 rapids and waterfalls ; can you see a reason for this ? 
 
 8. Compare the direction of the great rivers of Africa 
 with that of the greatest rivers of other continents, 
 
 383 
 
384 NATURE STUDY. [May 
 
 9. Compare Africa with respect to its lakes, both in 
 size and number, with the other continents. 
 
 10. From what region do the great rivers derive their 
 waters ? 
 
 11. Compare the rivers of Africa v/ith those of America 
 with respect to tributaries ; can you account for the con- 
 trasts observed ? 
 
 12. Where are the fertile regions in Africa? Cap you 
 account for them ? 
 
 13. What influences tend to make the coasts fertile and 
 the interior barren ? 
 
 14. Note carefully the boundaries of the Sahara Desert ; 
 can you understand why they are fixed when you find them ? 
 
 15. What causes can you assign for the position of this 
 desert ? Note the direction of the winds as indicated by 
 the arrows on a good physical map. 
 
 16. Compare the region in the same latitude in America ; 
 do you find a desert ? Can you see a reason ? 
 
 17. Compare with the different parts in Asia in the same 
 latitude ; what contrast do you find ? 
 
 18. Do any rain-bearing winds reach Africa from the 
 Atlantic Ocean ? Why ? 
 
 19. Can you see any reason for desert regions in the 
 southern part of the continent ? 
 
 20. Compare with South America in the same latitude ; 
 is there similarity or contrast ? 
 
 21. Compare the equatorial regions of Africa and South 
 America ; which region has the more luxuriant vegetation ? 
 In which is animal life more abundant ? 
 
 22. What has determined the location of the cities in 
 Africa ? Contrast their location with that of the cities of 
 other countries. 
 
 23. Can you see what things have contributed to give 
 
May] GEOGRAPHY. S^S 
 
 Egypt so conspicuous a place in history ? Compare and 
 contrast its natural advantages with Italy and Greece. 
 
 24. What are the natural obstacles in the way of African 
 exploration ? What physical features stand in the way of 
 trade ? 
 
 25. What are the valuable productions in the tropical 
 interior ? How are they carried to the cities ? 
 
 26. Why is it that there are no cities in the centers of 
 these productions as in other continents ? 
 
 27. Where are the raining regions ? What minerals are 
 found ? 
 
 • 28. By whom are the mines worked ? 
 
 29. What contrasts are found in the continent of Africa 
 and South America in the same latitude ? 
 
Ccoloai?. 
 
 FIELD LESSONS. 
 
 The importance of doing a great deal of field work with 
 beginners in geology cannot be overestimated. In fact, 
 there is but one way to begin, and that is by going into 
 the field. Such lessons are often less fruitful than they 
 might be because of a lack of system in the plan for it. 
 From the beginning of this month on to the end of the 
 school year, the season is likely to be suitable for outdoor 
 work, and a few hints as to the mode of conducting a field 
 lesson will be found useful. 
 
 As a rule it is best to have a definite thing to look for or 
 to study each time a field lesson is undertaken. Sometimes 
 all hope of good results is lost by calling it a picnic. This 
 term has a distinctive meaning of its own in the minds of 
 the children, and it has but little in common with serious 
 study. The pupils should be provided with baskets or 
 bags in which they may carry the specimens gathered, and 
 there should be a number of good hammers in the class. 
 A small pocket compass will also be found useful in get- 
 ting the exact direction of the dip and strike of rock. For 
 getting the angle of the dip use the instrument described 
 under Astronomy for September, on page 6i. If a lake 
 or stream is visited, a small wide-mouthed bottle will be 
 needed in which some water may be obtained and allowed 
 to settle to show the amount of silt in suspension. It should 
 
 386 
 
May] ' GEOLOGY. 387 
 
 be definitely understood at the outset that each pupil will 
 be held responsible for a description of what he has seen, 
 to be expressed in writing, a drawing, a painting, a clay 
 or sand model, as may best be adapted to the particular 
 circumstances of the case. All true education must de- 
 velop three great ideas — those of space, time, and force, and 
 the field lesson gives capital opportunity to broaden all 
 three. A few suggestive questions are appended. 
 
 1. What is the size of the area, you -wish to study ?• Its 
 length ? Its breadth ? Its area in square miles or acres ? 
 
 The area selected must not be too large. Take only 
 so much as will be needed to illustrate the point it is de- 
 sired to study. 
 
 2. What forces have given the surface its chief char- 
 acter ? Are they still at work ? Have the organic or in- 
 organic agencies done most of the work ? 
 
 3. Has the work within the selected area been one of 
 building or tearing down ? If tearing down, what counter 
 forces have retarded it ? If building, what counter forces 
 -have opposed ? 
 
 4. Which of the inorganic agencies, rain, snow, ice, 
 frost, etc., have been the most active ? 
 
 5. Have any forces acted here in the past which are 
 now quiescent ? 
 
 6. Note the work of running and standing water, if there 
 be anjT; is it destructive or constructive ? 
 
 7. Note the soil and subsoil, and compare both with the 
 underlying rock, if any is to be found. How was the soil 
 formed ? 
 
 8. Are the underlying rock strata horizontal or inclined ? 
 What is the amount and direction of dip in differentplaces ? 
 
 9. Are there fossils in the rocks ? Are ihey fossils of 
 animals or plants ? Land or water ? Fresh water or 
 
3^^ NATURE STUDY. [May 
 
 marine ? Are there any forms like them living at pres- 
 ent ? What present forms do they most closely resem- 
 ble ? 
 
 10. If a stream is studied, consider the course of the 
 channel ; is it changing at present ? How far has it in 
 the past deviated from its present course ? 
 
 11. Does the water contain silt in suspension?" Test 
 by allowing a bottle full to stand until it settles. Is the 
 water soft or hard ? Why ? 
 
 12. Are there any springs? Are they constant or in- 
 termittent ? Are they greatly and suddenly afifected by a 
 heavy rain ? Have you any means of telling whether the 
 underground reservoir is deep or near the surface ? Does 
 the water form a deposition near the outlet? What 
 is it ? 
 
 13. If a standing body of water is present, can you tell 
 what the source of the water is ? What hollowed out the 
 basin that holds the water ? Why does the water not sink 
 into the earth ? Is there an outlet ? Did it always oc- 
 cupy the spot it now does ? Is it changing its limits now ? 
 What is the cause of it ? Is there silt suspended in the 
 water ? 
 
 14. For suggestions as to the study of a marsh, see 
 Geology for April. See, also. Geology for September. 
 
 15. On the ground make necessary measurements and 
 sketches, and on returning make (a) drawings showing the 
 outline of the area studied, the course of the streams, 
 etc. {p) A model in clay or sand, showing the chief 
 features of relief, direction of elevations, valleys, de- 
 pressions filled with water, springs, etc. (f) Drawing or 
 painting, or both, showing the rock strata, their colors, 
 dip, fossils, etc. {d) A written description of the special 
 features of the lesson ; this may include description of 
 
May] GEOLOGY. 3^9 
 
 the soil, of the characteristic vegetation, and the probable 
 geological history of the region. Any or all of these 
 modes of expression should be required at- the discretion 
 of the teacher as the age of the pupils and the demands 
 of the lesson may seem to require. 
 
flDineralog^. 
 
 EXAMINATION OF SOILS. 
 
 One gf the most obvious things to any one who makes 
 a study of plant life is the close relation which exists be- 
 tween the growth of a plant and the character of the soil 
 that produces it. For this reason something should be 
 done in the course of the season to lead to a more or less 
 close examination of the different soils in which plants 
 are found growing. The work must of necessity be 
 mostly of a qualitative nature, and even in this line only 
 the simplest things can be noticed. It is well to keep in 
 mind during the study that the fertility of soil de- 
 pends upon its physical and chemical nature. A know- 
 ledge of. these properties is of grfeat practical value in 
 determining what plant food, if any, should be added 
 to it, and also what classes of plants are best adapted to 
 it. Some care should be used in selecting a specimen 
 for examination. Try to secure a block of it a few inches 
 square and as deep as the soil is to be found. Portions 
 of it may then be examined in the order in which it actu- 
 ally occurs in the ground. 
 
 It is thought best to briefly outline the entire pro- 
 cess for the mechanical analysis of soils, though the 
 wise teacher will decide whether it is best to have his 
 pupils go through with it all at once. Problems may be 
 given at different times as occasion requires, such as ; 
 
 39° 
 
May] MINERALOGY. 391 
 
 To find the amount of clay in a certain soil ; or, To ascer- 
 tain the amount of gravel, or coarse sand, etc. 
 
 1. What depth is the soil where you have examined 
 it ? What kind of subsoil is underneath ? Subsoil is 
 the layer immediately below the surface soil. 
 
 2. What depth is there to the subsoil ? 
 
 3. How has the soil been formed ? Is it made by 
 the rotting away, of the underlying rock, or has it been 
 carried to its present place from a distance ? 
 
 4. What part have plants played in forming the soil ? 
 
 5. How does the subsoil differ from the soil ? 
 
 6. Has the slant or position of the field had anything 
 to do with the formation of the soil ? 
 
 7. Has the soil ever had any fertilizers added to it 
 artificially to increase its productiveness? 
 
 8. Dry a small amount of the soil, rub up finely the 
 earthy lumps, and pick out the small stones it may con- 
 tain ; are they of one, or different kinds ? Use some of 
 the tests mentioned in the previous lessons to determine 
 some of their properties. 
 
 9. Weigh about three or four ounces of the dried soil 
 and pass it through a small sieve made from gauze in 
 which the meshes are one-tenth of an inch apart. Rub up 
 the earthy lumps so that all the fine material will pass 
 through. 
 
 10. Wash the part too coarse to pass through until thor- 
 oughly free from dirt, and dry and weigh it. How much 
 coarse gravel do you find in the soil ? What per cent, 
 of its entire weight ? 
 
 1 1. Take that part of the soil which passed through the 
 sieve and rub it through another, the meshes of which 
 are one-fifteenth of an inch apart. 
 
 12. Again take the part that is too coarse to go through, 
 
392 NATURE STUDY. [May 
 
 and wash, dry, and weigh ; this will give the amount of 
 gravelly sand in the soil. What per cent, is there ? 
 
 13.. Weigh a small amount of this gravelly sand and 
 heat it red hot for some time in a small crucible and 
 weigh again ; does it lose weight when burnt thus? Why ? 
 
 14. Take an ounce of the fine material that has 
 passed through the second sieve and boil it in a flask un- 
 til all the particles are completely separated. When cool, 
 rinse it out into a tall jar or bottle with a wide mouth. 
 By means of a funnel and long tube reaching nearly to 
 the bottom pour a gentle stream of water into the jar so 
 as to agitate the sediment. Set the jar in a larger vessel 
 and catch the overflow. 
 
 15. When the water runs away clear, pour off the water 
 and dry the remainder ; this will give the coarse sand 
 in the soil. What per cent, of the soil is it .? 
 
 16. Weigh a small amount of it after it is dried and 
 then heat it red hot in a crucible ; does it lose weight ? 
 Why ? What kind of substances burn ? What kind can- 
 not be consumed in the fire ? 
 
 17. Repeat the process described above with the 
 overflow from the jar ; this will give \k\.t, fine sand. Do 
 not agitate so strongly as in the firsts instance. Does it 
 lose weight by being burned ? 
 
 18. Subtract the weight of the coarse and fine sand from 
 the weight taken in the beginning and it will give the 
 amount of clay in the soil. What per cent, is it of the 
 whole amount ? 
 
 19. Where does the sand come from that you have 
 found in your sample of soil ? Was it derived from the 
 underlying rock ? 
 
 20. Can you account for the presence of the gravel 
 that you found ? Are the pebbles all of the same kind ? 
 
May] CHEMISTRY. 393 
 
 21. Where did the clay come from ? 
 
 22. How was that part of the soil formed that was con- 
 sumed in the fire when heated ? 
 
 23. Which element found in the soil is best for vegeta- 
 tion ? Which is the poorest ? 
 
 24. Why is gravel poorly adapted for plants ? Does 
 its presence add or detract from the fertility of thesoil ? 
 
 25. What are the advantages and disadvantages of 
 sand for vegetation ? 
 
 26. Which is better for plants, clay or sand ? Why ? 
 
 27. What properties of loam make it valuable for 
 plants.? 
 
At this season of the year, the material which might be 
 taken up in this subject for study has become so abun- 
 dant that it is difficult to make a selection. The decision 
 as to what shall be studied may be left, partly at least, to 
 the pupils themselves, due regard being given to the ease 
 with which specimens may be obtained. 
 
 Insect life presents great variety, and, also, abundance 
 of interesting material upon which many profitable les- 
 sons may be given. Enough work should be done along 
 this line to lead the pupils into inquiry concerning the 
 habits of the various kinds found, their relations to plants, 
 and the structures by which they are adapted to their 
 modes of life. 
 
 It will be possible during this month to observe the 
 newly hatched birds and the treatment they receive from 
 the old ones. The work of the earthworms may be fol- 
 lowed up according to the suggestions offered for the 
 previous month and, in fact, any of the work begun in 
 the spring may be continued now. 
 
 BIRDS. 
 
 1. Upon what kinds of food are the young birds fed? 
 Do the old ones prepare it in any way for the young 
 birds ? 
 
 2. What feathers appear first upon the young birds ? 
 
 3. Do the feathers grow evenly over all parts of the 
 
June] ZOOLOGY. 395 
 
 body ? Can you see any reason why certain spaces are 
 left bare ? 
 
 4. How long after hatching is it when the young birds 
 attempt to fly ? Do the old birds render the young ones 
 any assistance ? 
 
 5. Which parent do the young ones resemble more 
 closely ? Can you see a reason for it ? 
 
 6. What dangers threaten the young ones at this time ? 
 
 7. What evidences do you have that bear upon the 
 chances of the young birds for life? Compare with the 
 chances of infantile human life. 
 
 8. What are .the rnost active destroyers of bird life ? 
 What means of escape have they ? . 
 
 9. Select feathers from different parts of the body and 
 compare them. 
 
 10. In a large quill-feather selected from the wing, note 
 the following points : [a) the central shaft bearing on 
 both sides, (]>) the vane j (r) the quill, that part of the 
 shaft below the vane. The small branches making up 
 the vane are called barbs j these are interlocked by means 
 of the bar-bules. Note how this is done. Why is it so ? 
 
 It. Compare a down feather with a quill ; where is the 
 chief difference ? What difference in use is there between 
 the down and quill-feathers ? 
 
 12. Are the feathers waterproof ? Explain. 
 
 13. Note the arrangement of the feathers in the wings ; 
 what form do they give to the wing ? 
 
 14. Do you. know of any long legged birds that have 
 long tails ? Have you seen any short legged birds with 
 very small tails ? What have you noticed about the flight 
 of such birds ? When a bird is flying, is its neck stretched 
 out or drawn back ? Can you see a reason ? 
 
 IS- Can you see what determines the line of flight of 
 
39^ NATURE STUDY. [June 
 
 a bird ? Note the form and relative size of the body, 
 wings, tail, and legs. 
 
 i6. Try to count the strokes of the wings of different 
 birds while they are flying ; can you move your arms for 
 five minutes with equal rapidity ? 
 
 INSECTS. {See, also. Zoology for September^ 
 Bees. 
 
 1. Watch closely a bee, either bumble bee or honey 
 bee, in its visits among flowers ; can you tell why its 
 visits are made ? 
 
 2. Do they visit different flowers promiscuously or only 
 those of the same kind ? 
 
 3. Do honey bees and bumble bees' visit the same 
 flowers ? Examine the bees closely for a reason for what 
 you observe. 
 
 4. By what means do they cling to the flowers ? How 
 do they examine-a flower ? 
 
 5. Do they injure the flowers by their visits ? . Can you 
 see what they carry away ? Examine their legs and 
 backs. 
 
 6. Can you see any use for the hairs that are found on 
 the bee's legs and body ? 
 
 7. How do they manage to reach the nectar of the 
 flower ? Can you see how they carry it ? The nectar is 
 stored up in the crop — one of the divisions of thealim.en- 
 tary canal — and is then elaborated or changed into honey 
 by a process not yet fully explained. 
 
 8. How do bees hum ? Is it always on the same key ? 
 Can you tell how rapidly the wings vibrate ? (See 
 Physics for May under Sound.) Compare the wings 
 with those of the butterfly and beetle. 
 
June] ZodzOGY. 397 
 
 9. Can you find any evidence of sight or hearing ? If 
 so, can you locate the organs ? 
 
 10. When a bee has secured its load, notice its flight ; 
 is a " bee-line " a straight line ? 
 
 Ants. 
 
 Suggestions have already been made as to how ants 
 may be confined for the purposes of indoor observa- 
 tion. (See. Zoology for October.) But, it is of great 
 interest to observe them at work at this season outdoors. 
 Ant-hills are to be found in almost every field or bit of 
 woodland where the soil is rather light and dry. Along 
 paths and roadsides the work of a small red ant may be 
 observed. 
 
 1. Do ants and earthworms work together in the 
 same soils ? Can you see any reasons for the difference 
 in the locations that are chosen ? 
 
 2. Look into the nests and secure if possible some of 
 the small, almost cylindrical bodies usually to be found, 
 which most people call eggs ; are they eggs ? Can you 
 find eggs ? 
 
 3. Do the ants move them regularly ? When do they 
 bring them out ? When do they take them back ? What 
 is accomplished by this care ? 
 
 4. How do they Carry their burdens ? Can you trace 
 any resemblance to the crawfish ? 
 
 5. Can they see or hear ? Cp,n you find either eyes or 
 ears ? 
 
 6. What do they eat ? Can you tell from their mouths 
 which they prefer, solid or liquid food ? 
 
 7. If you can find a densely populated ant-hill, place 
 in it or near it a dead mouse inclosed in a box. Leave 
 entrances fof the ants, and you will not only feed the 
 
39^ NATURE STUDY. [June 
 
 ants, but, by and by, you will have a nicely prepared 
 mouse's skeleton for yourself. 
 
 8. Can you find any small plant lice on plants near 
 the ants' home? If so, watch closely and try to find 
 out whether or not the ants take any notice of them. 
 
 9. Do the ants store up food as the bees do ? How 
 do they employ their time ? Have they honestly earned 
 their reputation for industry ? 
 
 10. Do ants of different sizes live together ; are they 
 the same or of- different kinds? Do ants living indif- 
 ferent hills communicate with each other ? Are they 
 friendly or hostile ? Try placing strangers in one of the 
 
 hills. 
 
 Spiders. 
 
 1. In what locations do you find spiders ? Select one 
 or more places for observation, and, if possible, try to 
 observe one spinning a web. 
 
 2. How is the silk obtained for the web ? 
 
 3. What fpet do they use in fastening their silk as it is 
 spun? How do they place their long guys which sus- 
 pend the web ? Do they repair old or broken webs ? 
 
 4. Where do they begin to spin the circular threads, 
 in the middle or at the circumference of the web ? At 
 what time do they spin the web ? 
 
 5. Examine some of the filmy webs that may be found 
 on the roadside ; how do they differ from those that are 
 suspended ? where do j'ou find the spider ? To dis- 
 cover his whereabouts drop a fly on the web or shake it 
 slightly. 
 
 6. In what position does the spider place himself in 
 one of the suspended wheel-like nests ? Why ? 
 
 7. Do they eat solid or liq-uid food? Do they make 
 any use of plant food ? 
 
June]' ZOOLOGY. 399 
 
 8. Where do they lay their eggs ? Sometimes the 
 mother spider may be seen carrying a large white ball ; 
 what is it ? 
 
 9. In what way is the use of the spider's cocoon 
 different from that of the moth ? 
 
 10. Can you discover the way in which the mother 
 spider cares for her young ? 
 
 11. How does the spider differ in its structure from 
 the bee and ant ? Compare as to the number of legs, 
 parts of the body, etc. 
 
 The House-fly. 
 
 1. Place a grain or two of moistened sugar upon a 
 table and notice how a fly takes it up ; does it eat it as 
 a solid ? 
 
 2. How do its mouth parts differ from those of the ant ? 
 
 3. Does it make any use of its feet in eating ? By 
 moving a magnifying glass up cautiously, the mode of 
 managing food may be clearly made out. It is an in- 
 teresting observation. Can you account for various 
 movements it makes with its legs and wings at intervals 
 while eatingj 
 
 4. What evidence have you that it can see ? Can you 
 determine whether it can hear ? 
 
 5. Does it move its legs in the same order as the ant ? 
 
 6. Examine its foot ; can you account for the way by 
 which it clings to a pane of glass or the ceiling ? 
 
 7. Can you find any evidence that it breathes ? 
 
 8. Has it the sense of smell ? Do not guess at the 
 answers, but find actual proof from close observation. 
 
 9. Where do they lay their eggs ? What comes directly 
 from the egg ? Compare with the ant, the bee, and the 
 spider. A small piece of meat exposed-to the warm su5 
 
400 NA TURE STUD Y. ■ [June 
 
 will very soon enable the pupils to see the early stages 
 of a fly's life. Is it the house-fly that lays its eggs upon 
 meat ? 
 
 lo. Can you tell how rhany vibrations the wings make 
 in a second ? (See Physics for May.) Compare with 
 a bee. 
 
 Beetles. 
 
 i. These are at once recognized by the hard shiny 
 coats and wings. "Where are they most abundant ? 
 
 2. Can you see a good reason for the contrast between 
 the beetle and bee in regard to their wings ? 
 
 3. How are the wings employed in flying ? Can you 
 find any beetles that do not fly ? 
 
 4. Can you find any beetles that do not spread or 
 open the outer wings ? 
 
 5. What is the food of beetles ? Examine the mouth 
 parts ; compare with the fly, the ant, and the spider. 
 
 6. Can they see or hear ? Where are the organs of 
 seeing and hearing ? 
 
 7. What enemies do they have ? How do they es- 
 cape ? Have they means of attack or defense ? 
 
 8. Can you find any insects , that are injurious to 
 plants ? 
 
 9. Have you found any that are beneficial to plants ? 
 iq. Have you found any insects that are either bene- 
 ficial or injurious to man ? 
 
 REPTILES. 
 
 It would be nothing less than wonderful for the season 
 to pass by without one or more members of this group 
 of animals being found and brought in by some of the 
 pupils. Turtles are abundant in streams, usually, and 
 are easily kept in an aquarium or even in a pail of 
 
June] ZOdLOGY. 40I 
 
 water. A small piece of raw meat now and then is all 
 the food they require. A snake, repulsive as it is to most 
 people, is nevertheless an interesting object for study. 
 The teacher should rise above his unnatural prejudices 
 against this creature for the sake of the children who are 
 dependent upon him for the truth concerning nature, 
 and try to have them grow up with less of the unnatural 
 horror than he has himself. 
 
 Snakes. 
 
 1. A snake may be kept in a box with a glass cover 
 over it. There should be a. little dried grass or other 
 material in the box to afford at least partial means of con- 
 cealment. 
 
 2. Can you discover any signs of intelligence ? Does 
 it show signs of fear ? 
 
 3. What is the meaning of the frequent darting out of 
 the tongue ? Many people have an idea that this is a 
 weapon of defense or attack ; is it so ? 
 
 4. It is interesting to see the small striped garter snake 
 capture its prey ; put a mouse in the box and watch the 
 operation. If you can find a poisonous snake compare 
 the two in this respect. 
 
 5. Turn the box upside down so that the snake will 
 lie on the glass ; can you see from beneath how the 
 snake movfes ? 
 
 6. Compare its motions with those of the earthworm. 
 
 7. Do the scales on the under side play the same 
 part that the spines of the earthworm do ? How do the 
 scales-on the sides differ from those on the under side ? 
 
 8. Is the snake propelled by means of the scales alone ? 
 
 9. Does the snake wink ? Compare with the turtle. 
 
 10. Are the upper and under sides of the snake more 
 
402 NATURE STUDY. [June 
 
 or less unlike than in the case of the earthworm ? 
 What reason can you give ? 
 
 Turtles. 
 
 1. How does the turtle compare with the snake as to 
 intelligence ? As to activity ? As to expressions of 
 fear ? 
 
 2. Does it have any actions or habits in common 
 with snakes ? What differences ? 
 
 3. What would seem to be the use of the hard shell? 
 Compare the shells of water turtles with those found 
 on dry land ; can you see a reason for the differences ? 
 
 4. Do turtles chew their food ? How do they seize it ? 
 
 5. By what means do they swim ? Compare the 
 swimming powers with a fish and a frog. 
 
 6. Has it any advantages over either ? Are there any 
 disadvantages ? 
 
 7. Does it wink ? Are you reminded of any other 
 animal examined in this respect ? 
 
 8. What modes of attack have they ? What are their 
 enemies ? 
 
 9. Turtles lay their eggs at this season in the sand on 
 the shores of streams and ponds ; try to find a nest. 
 
 10. Note their breathing, and compare with the silake, 
 frog, and bird. 
 
Botan?. 
 
 In elementary work in the subject of botany, usually, 
 comparatively little is planned in any practical manner 
 for a study of planfphysiology. It is not difficult, how- 
 ever, for the pupils to perform a number of experiments 
 which will do much in illustrating plant action. By 
 similar means, some notion of the chief constituents of 
 the plant may be gained. 
 
 1. Carefully remove from the soil any small vigorous 
 plant having a number of leaves. Gently wash away the 
 adhering earth and dry with a cloth or blotting paper, 
 and weigh it as accurately as possible. 
 
 2. Place in an oven or near the fire and dry it com- 
 pletely without scorching, and then weigh it again ; how 
 much loss by drying ? What per cent. ? What part of 
 the plant's constituents remain ? 
 
 3. What caused the plant to lose weight ? Let different 
 pupils try different plants. Try the same plant in dif- 
 ferent locations ; how does the location affect the loss 
 TpsT cent. ? 
 
 4. After finding the loss of weight, cut or break the 
 dried plant into small pieces and heat them in a test tube 
 or crucible until no further change takes place ; what 
 now remains ? What was formed before the final residue 
 was obtained ? What became of this as change took 
 place? (See Chemistry for December and February.) 
 
 5. Weigh the residue found in (4) and find what per 
 
 403 
 
404 NATURE STUDY. [June 
 
 cent, it is of the fresh plant. What per cent, is it of the 
 dried plant .'' 
 
 6. Test the residue with a little hydrochloric acid ; is 
 there any action ? 
 
 7. Stir up a little of the residue with distilled water 
 and test with litmus paper. (See Mineralogy for April.) 
 Can you determine anything regarding the character of 
 the residue after burning ? 
 
 8. In the same way tests may be applied to different 
 kinds of wood, leaves, bark, etc. ; what part of- the plant 
 has the most dry, solid matter ? Which part the most 
 carbon ? 
 
 9. Remove from the ground any small healthy plant 
 and cleanse the roots as before. A seedling maple or 
 ash, or any woody plant is to be preferred. The top of 
 the plant should not be too large to be covered by a 
 
 .tumbler or small glass jar. 
 
 10. Cut a piece of cardboard large enough to support 
 an inverted tumbler, and through a hole in the center 
 pass the roots and part of the stem of the plant Seal the 
 opening about the stem with tallow or wax and suspend 
 the roots in a wide-mouthed bottle of water. Invert over 
 this another tumbler and seal it around the edge. Ar- 
 range two tumblers thus and place one in sunshine and 
 the other in the shade. 
 
 11. What do you observe in the two inverted tumblers ? 
 Note the effect of different temperatures. 
 
 12. What does this experiment show you aboujt the 
 roots of a plant ? About the stem ? About the leaves ? 
 
 13. Prepare another plant in the same way but use a 
 cork instead of the cardboard (the inverted tumbler not 
 being needed). Dry the plant and weigh it. Suspend 
 the roots in a small bottle of water, Bore a hole through 
 
June] BOTANY. 405 
 
 the cork, and then cut into it a lengthwise slit from the 
 side, through which the stem may be passed without 
 injury to the root. Seal the bottle tightly and weigh 
 carefully. Plape in the sunshine for two hours and 
 ' weigh again. 
 
 14. Can you notice change in weight ? How do you 
 account for it ? 
 
 15. Place it for the same length of time in a dark 
 closet and weigh again ; what is the result ? 
 
 16. Compare the amount of change during the day with 
 that during the night. 
 
 17. Compare the amount of change during a cloudy 
 day with that during one of sunshine. 
 
 18. To what part of the plant is this passage of water 
 chiefly due ? Prepare another plant in the same way, tut 
 remove the leaves. Also another plant with the stem cut 
 off above the roots ; which bottle loses most in weight ?, 
 
 19. Estimate the square inches of leaf area of one of 
 your plants. Count the leaves on a branch of the tree 
 you have selected for study and estimate its entire leaf 
 surface. How much water could it, under the same con- 
 ditions, lift in one day ? 
 
 20. When done with the foregoing experiments, remove 
 the plant and carefully remove the adher!ng wax and 
 water and weigh it ; has the plant lost or gained since 
 you prepared it ? If scales are not convenient, ask any 
 druggist or grocer to do the weighing for you. 
 
 21. The passage of water through the plant is called 
 transpiration. What conditions outside the plant do you 
 find most favorable for it ? What is the chief cause ? 
 What parts of the plant promote it ? 
 
 22. Fill a good sized test tube with water and immerse 
 in it 3, small stem with the leaves of some water plant ; 
 
4o6 NATURE STUDY. [June 
 
 place in the sunshine and observe closely. Are there any 
 signs of plant action. 
 
 23. Remove to the shade ; does it affect the action ? 
 If possible try different temperatures. 
 
 24. Use boiled water ; is there any change in the 
 action ? 
 
 25. Blow the breath into the water by means of a small 
 tube ; can you notice any effect ? 
 
 26. What is it likely the water must contain, judging 
 from the above experiments, in order that plant action 
 may take place ? 
 
 27. By placing plants and leaves of different kinds in a 
 similar manner in small bottles of water, try to collect 
 some of the gas given off and test it to find out what it is. 
 (See Chemistry for preceding months.) 
 
 LEAVES. 
 
 1. On what part of the tree are the leaves most vigor- 
 ous? Where least so. 
 
 2. On what part of the branch are they most thrifty ? 
 Can you account for this ? 
 
 3. Do you observe any regularity in the arrangement 
 of leaves ? Can you account for it ? 
 
 4. Are they arranged equally on all sides of the 
 branch ? Does their arrangement depend in any way 
 upon the direction that the branch grows ? Compare 
 different kinds of trees. 
 
 5. How many ranks or distinct rows of leaves can you 
 count upon your twigs ? Wind a string around the twig 
 making it cross the nodes ; how many times does it pass 
 around the twig until it crosses a bud over the one started 
 with ? How many ranks are crossed in reaching this 
 point ? 
 
June] SO TANY. 407 
 
 6. The ranking arrangement is expressed by a fraction 
 whose numerator is the number of times the string passes 
 round the stick, assuggested in (5), and whose denominator 
 expresses the number of ranks. 
 
 7. What is the size of the angle between any two ranks ? 
 What part of the entire circumference is it ? Compare 
 with the fraction found in (6). The size of the angle 
 between two successive ranks is called the angular 
 divergence of the leaves. Study the twigs on a number 
 of different trees and determine the number of ranks, 
 angular divergence, etc. 
 
 8. Can you see any reason why the leaves of any 
 particular kind of tree take the shape they have ? 
 
 9. Why should they all be approximately the same shape 
 on the same tree ? 
 
 10. Can you find any two of exactly the same shape ? 
 What is the cause of the variations noticed ? 
 
 11. Of what advantage is the petiole, i. e., the leaf" 
 stalk ? Such leaves are' said to he petiolate. 
 
 12. Compare a plant with petiolate leaves with one that 
 has sessile leaves, i.e., those without foot stalks ; can you 
 see any advantage to the plant in the sessile leaf ? 
 
 13. Note the two common varieties of netted venation, 
 the pinnately-veined, i.e., those having a mid rib with 
 "diverging veins, and palmately-veined, or those having 
 several ribs of equal size radiating from a common point. 
 
 14. In the pinnate leaf do you find both sides alike in 
 any specimen ? What causes the difference ? Note the 
 relation of one leaf to another and to the branch that 
 bears it. 
 
 15. Can you find any leaves that appear to be transitional 
 between the two leading types ? 
 
 16. Note the leaves borne by the ash tree or locust tree ; 
 
4o8 MATURE STUDY. [Jun6 
 
 these are compound leaves. Also the leaves of the 
 poison ivy, or Virginia creeper ; compare these two types 
 of compound leaves with the two classes of simple leaves. 
 The ash leaf Ss, pinnately compound axid the Virginia creeper 
 is palmately compound. Can you find intermediate forms 
 between compound and simple leaves ? 
 
 17. What is the real difference between the pinnate 
 and the palmate type of leaves ? 
 
 18. Compare the venation of the above mentioned leaves 
 with that of grass blades, and flags, and all lilies ; what 
 difference do you find ? The latter are parallel-veined 
 leaves. 
 
 19. Which kind of plants are most numerous, those with 
 netted or parallel veined leaves ? 
 
 20. What kinds of seeds produce those plants that bear 
 netted veined leaves ? (See Botany for April.) Do you 
 find any exceptions ? 
 
 21. What kind of seeds produce plants with parallel- 
 veined leaves ? -Look for exceptions. 
 
 2 2 . Compare the stem of a woody plant, as the ash, maple, 
 or oak, with a stalk of corn ; how is the new material which 
 goes to thicken the stem added in each ? Compare the 
 leaves of the woody plants mentioned with those of the 
 corn. Compare the seeds from which they grow. 
 
 23. Carefully remove the bark from any twig or branch 
 that is alive and note the different layers ; compare with 
 what you observed in early spring. (See Botany for 
 March.) 
 
 24. Can you tell why the bark has become more loosely 
 attached to the wood ? Is it entirely separated ? 
 
 25. Scrape up a little of the sappy layer and rub be- 
 tween the fingers ; is it pure water ? Compare with the 
 
June] BOTANY. 409 
 
 watery substance which you find in young leaves and 
 twigs. 
 
 . 26. This sappy layer is called the cambium, or the cam- 
 bium layer ; can you see what it does for the plant ? You 
 must watch the growth carefully before trying to answer 
 this 'question. 
 
 27. Can you find a cambium layer in the corn- 
 stalk ? 
 
 28. Plants whose stems grow in thickness by means of the 
 cambium layer are called exogens, and are said to be ex- 
 ogenous. Exogen means growing on the outside. Plants 
 whose stems thicken by general growth throughout the 
 stem are called endogens, and are said to be endogenous. 
 Endogen means growing within. 
 
 29. Which are more abundant in our latitude, exogens or 
 endogens? Compare the two kinds as to their buds and 
 branches. Compare the locations where the two classes 
 of plants are found. , 
 
 30. Look in pictures of tropical scenes for endogenous 
 plants, conspicuous among them being the palms. Note 
 the branches. In some kinds the whole'Iife of the tree is 
 dependent' upon the life of the terminal bud : when that is 
 destroyed the plant dies. 
 
 31. Compare the flowers of the parallel-veined leaved 
 plants with those having netted-veined ; what is the ruling 
 number in the parts of each whorl in the former ? (See 
 Botany for May.) 
 
 32. What contrasts do you observe between exogens 
 and endogens ? Compare as to seeds, stems, leaves, and 
 flowers. Have you found any plants that form exceptions 
 to the rule ? 
 
4IO NATURE STUDY. [June 
 
 THE GRASSES. 
 
 The best material, perhaps, which can be used in the 
 beginning of the study of grasses is wheat or rye in blos- 
 som. This may be obtained almost anywhere during 
 this month. 
 
 1. What peculiarities distinguish rye from other plants 
 studied thus fa* ? 
 
 2. Can you see a reason why its flowers are not 
 colored ? Have they any odor ? Have they nectar ? 
 
 3. Do insects visit these flowers ? Why ? 
 
 4. What is most conspicuous about the flower ? Com- 
 pare in this respect with other flowers previously ex- 
 amined. Can you see a reason for the difference ? 
 
 5. Compare the stem in point of size with that of other 
 plants. How does it compare in strength ? In weight ? 
 Is the slender stem of any advantage to the plant ? 
 
 6. The hollow jointed form of stem is called a culm. 
 The form of inflorescence is a compound spike. The dif- 
 ferent parts borne upon the axis of the flower-cluster are 
 called spikelets. 
 
 7. The outer husks in the spikelet are called the upper 
 and lower glumes. Inside of these, look for the floral 
 whorls. The chaffy scales are the palets — inner and outer. 
 At the base of these look for two minute scales called 
 lodicules. What whorl of the flower do they represent ? 
 Note the feathery (plumose) stigmas. 
 
 8. Compare the amount of pollen produced by grains 
 and grasses with that of other plants ; can you see why 
 a great quantity is needed ? 
 
 9. Compare some of the common grasses with the 
 grains that have been examined ; do the parts corre- 
 spond ? 
 
June] PHYSICS. 4" 
 
 10. What resemblances and differences do you find be- 
 tween wheat, rye, oats, etc., and Indian corn ? What 
 constitutes the tassel in corn ? What is it that forms the 
 ear? 
 
 11. When are the different cereals planted or sown ? 
 How long does it take them to mature ? 
 
pb^0ic0. 
 
 ELECTRICITY. 
 
 There is no more interesting department of physics 
 than that of electricity, and certainly there is no one of 
 greater practical importance at the present day. Owing 
 to the fact, however, that to get much out of the subject 
 in an elementary course that is of practical value, con- 
 siderable apparatus of some complexity is required, not 
 much beyond a few simple experiments, showing some^ 
 thing of the nature of electricity, can be attempted in the 
 common schools at present. As an offset to the difficulties 
 in the way regarding apparatus, there is the deep interest 
 which pupils almost invariably show in the subject, which 
 will impel them to greater efforts in the preparation of 
 needed materials. 
 
 MAGNETISM AND FRICTIONAL ELECTRICITV. 
 
 1. Dip a common magnet (see Physics for September) 
 into a pile of iron filings or small carpet tacks ; will they 
 stick equally well all round the bend in the magnet ? 
 
 2. Magnetize a large knitting needle, as directed in Sep- 
 tember, and test it with iron filings. Enough filings may 
 be obtained by filing a piece of soft iron or a nail for a few 
 minutes. Place them on a sheet of white paper. Do the 
 filings adhere equally well along its entire length ? Break 
 the needle in the middle and try again. 
 
 3. A straight magnet like the knitting needle is called 
 
June] ' PHYSICS. , 413 
 
 a bar magnet ; one that is bent, like those used in Sep- 
 tember, is a horseshoe magnet. In what respect are the 
 two kinds alike in the attraction of filings ? 
 
 4. Procure some pith, such as may be found in an elder 
 or cornstalk and thoroughly dry i't. Make two small balls 
 from it about the size of a pea, and suspend them an inch 
 apart by a fine silk thread, -eight or ten inches long. 
 Fasten the upper ends of the threads to a wooden sup- 
 port by means of a drop of sealing wax. 
 
 5. Rub a stick of sealing wax briskly upon the sleeve 
 or with a dry piece of flannel for a minute, and then bring 
 the wax near the balls. At what distance do you notice 
 the influence of the wax upon the balls ? 
 
 6. What happens after they have clung to the wax for 
 a short time ? After they have left the wax rub it again 
 and bring it near ; it is now said to repel the balls, while 
 a moment before it attracted them. 
 
 7. Rub a glass tube or rod instead of the sealing wax 
 and bring it near the balls ; are they attracted or repelled ? 
 ' 8. When they are repelled from the rod, again bring the 
 sealing wax near ; are they attracted or repelled ? When 
 they are repelled from the sealing wax, bring the glass rod 
 near ; are they attracted or repelled ? 
 
 9. Instead of the sealing wax^ use a gtitta-percha pen- 
 holder or comb ; do the balls behave toward it as they do 
 toward the wax, or as they do toward the glass ? 
 
 10. Bring the wax, the glass tube, and the comb, after 
 rubbing vigorously, close to some bits of paper or cotton ; 
 are they attracted and repelled in the same way ? 
 
 11. Bring the excited wax and glass near your magnetic 
 needle ; is there any effect? Does it repel either end ? 
 
 12. Rubbing the glass and wax produced electricity by 
 friction. When the pith balls flew to either they re- 
 
414 NATURE STUDY. [June 
 
 mained until charged. The silk thread prevents this from 
 escaping very rapidly, if the air is dry. 
 
 13. That received from the wax is called negative 
 electricity ; that received from the glass is called positive 
 electricity. 
 
 14. Rub both the glass and the wax and bring them close 
 to the pith ball on opposite sides ; what takes place ? 
 
 15. What do you notice when the ball becomes charged 
 with negative electricity ? What happens when it becomes 
 charged with positive electricity ? 
 
 16. When two bodies are charged with the same kind oi 
 electricity how do they behave toward each other ? How 
 is it when they are charged with the opposite kinds of elec- 
 tricity ? 
 
 17. Any contrivance like the pith ball which will 
 show the presence of electricity is called an electro- 
 scope. Use it to test whether electricity may be ob- 
 tained by rubbing silk, paper, and other substances. 
 
 18. Charge the pith ball with electricity from the glass 
 tube, as above described. Now bring near to it a piece 
 of silk ribbon which has been briskly rubbed ; can you 
 tell whether the silk is charged with negative or positive 
 electricity ? How may the electroscope be used to tell 
 the kind oi electricity developed in any substance? 
 
 19. By rubbing a stick of sealing wax vigorously for 
 some time with dry flannel, a slight crackling sound will 
 be heard when it is brought near the knuckle ; in the 
 dark a tiny spark may be seen. The same kind of sparks 
 may be seen when a cat's back is rubbed, and the same 
 crackling sound will be heard. 
 
 20. Can you develop electricity by rubbing an iron 
 rod as was done with the glass and sealing wax ? 
 
 31. Wrap one end of the iron rod well with a silk 
 
June] PHYSICS. 41 S 
 
 handkerchief, rub thoroughly, and test with the pith ball 
 for electricity ; anything which prevents an object from 
 losing its electricity is called an insulator. 
 
 22. Rub one end of a long stick of wax and bring the 
 other end close to the pith ball or a bit of cotton ; does it 
 show the presence of electricity ? 
 
 , 23. In the case of the iron, in the first instance, the 
 electricity passed over the iron to the hand and through 
 the body to the ground as fast as formed, but not so with 
 the sealing wax. Any substance like the wax in this re- 
 spect is called a non-conductor j when like the iron, it is 
 called a conductor. 
 
 24. Lightning is a large spark of electricity passing 
 from one cloud to another or from a cloud to the earth ; 
 can you see a use for lightning rods ? Why are they usu- 
 ally fastened to the roof and sides of the house by being 
 passed through glass rings ? What is the proper name 
 for the rings ? 
 
 VOLTAIC ELECTRICITY. 
 
 1. Place a piece of zinc, about three inches long and 
 two inches wide, in a glass of water to which half a tea- 
 spoonful of sulphuric acid has been added ; what takes 
 place ? Is it a chemical or physical change ? 
 
 2. Place in, the same vessel a strip of copper of same 
 size. Punch a small hole through the ends of the copper 
 and zinc not immersed, and pass through each a small 
 copper wire a foot long. Bend the outer ends of the 
 copper and zinc over the edge of the tumbler so that they 
 will remain in place without touching. 
 
 3. Put, first, the end of the copper wire from the zinc in 
 the mouth, and then that from the copper ; is there any 
 taste noticeable ? 
 
4i6 NATURE STUDY. Dune 
 
 4. Place the ends" of both wires in the mouth without 
 allowing them to touch ; do you note any difference in 
 taste ? Note "what is taking place in the tumbler. 
 
 5. Procure several feet of insulated copper wire, such 
 as is used for door-bells, and wind two or three feet of 
 it lengthwise around a block, two inches long and one 
 inch wide, in an even coil. Place this coil beneath your 
 magnetic needle and close to it, with the wires running 
 parallel with the needle. 
 
 6. Bring the wire from the copper strip into contact 
 with one end of the wire in the coil, and, watching the 
 needle sharply, place the wire from the zinc in contact 
 with the other end ; does the needle give any evidence 
 of disturbance ? Which way does it turn? 
 
 7. Touch the ends of the coil with the opposite wires 
 from the copper and zinc ; what changes in the behavior 
 of the needle ? 
 
 8. Such a coil with a needle attached is called a galvan- 
 ometer. 
 
 9. Another form easily made may be constructed thus. 
 Take a block of pine wood five inches square and two 
 inches thick. Saw'each corner off, making it octagonal in 
 shape. Cut a hole through the middle about two and 
 one-half or three inches in diameter. Within the ring of 
 wood thus formed suspend a magnetized sewing needle 
 (see Physics for September) by a single fiber of a silk 
 thread. The thread is easily attached to the wood by a 
 drop of sealing wax. Wrap around the ring on the out- 
 side, smoothly and evenly, eight or ten turns of the in- 
 sulated copper wire. A groove should be cut on the un- 
 der side of the ring to receive the coil of wire so that the 
 ring may be fastened to a block about the same size for a 
 base. No iron should be used in the construction of this 
 
June] PHYSICS. 417 
 
 instrument. Why ? It is more convenient to have the 
 ends of the wire in the coil near each other. Place the 
 ring in such a position that the wire in the coil will 
 be parallel with the needle when it points north and south. 
 Bring the wires from the copper and zinc strips in con- 
 tact with the ends of the coil and observe the needle. 
 Change the wires to the opposite ends of the coil and 
 note the difference. 
 
 10. The needle is turned, deflected, by what is called 
 a current of electricity which is generated by the action 
 of the acid and water on the zinc and copper. Anything 
 which will thus generate electricity by chemical action is 
 a battery. 
 
 11. The direction of the current is also determined from 
 observation of the needle. If the current passes from 
 north to south above the needle, or from south to north below 
 it, the north pole of the needle is deflected toward the 
 east. If the current passes from north to south below the 
 needle, or from south to north above it, the north pole of 
 the needle is deflected toward the west. Do you see any 
 way by which the needle may indicate the strength of the 
 current ? 
 
 12. Another way to make a battery is as follows : pro- 
 cure about fifteen copper cents and an equal number of 
 pieces of sheet zinc, cut in squares, the edge of each be- 
 ing equal to the diameter of the cent. Cut, also, thirty 
 squares of cloth or blotting paper of same size of the 
 zinc. Of these make a pile : first a piece of zinc, then a 
 square of cloth, then a cent, then a square of cloth, then 
 zinc, and so on. When finished, bind them together 
 tightly with a strong cord. Two copper wires must either 
 be soldered, one to the zinc and one to the copper at the 
 opposite end, or else tied tightly against the two pieces. 
 
41 8 NATURE STUDY. [June 
 
 This is called a Voltaic pile, from a man named Volta, 
 an Italian, who first used this means of producing elee- 
 tricity. 
 
 13. The acid and water may be used with this bat- 
 tery, but a better fluid may ie made as follows for a 
 few cents : Water, one pint ; bichromate of potash, two 
 ounces ; sulphuric acid, two ounces. Powder the bichro- 
 mate and dissolve in the water ; afterward add the acid 
 in a fine stream, stirring all the time, and allow it to 
 cool. When the battery is not in use remove the pile 
 and rinse thoroughly, and it will last for some time. 
 
 14. Another battery, easily and cheaply made, and which 
 will gi?^e a current of sufficient strength to ring a door-bell, 
 may be made thus : Procure two sticks of carbon, each 
 about eight inches long, such as are used in electric lights, 
 and two pieces of zinc of same length, and about one- 
 fourth of an inch square. Any dealer in electrical sup- 
 plies can furnish them, provided with binding screw, for 
 ten cents each. Cut a strip of wood six inches long, an 
 inch wide, and half an inch thick. One inch from each 
 end bore a hole sufficiently large to-let the carbon sticks 
 pass through, and fasten a carbon in each one, allowing 
 about an inch to project abdve. To the side of the 
 stick next the carbons bind or clamp the zincs. Connect 
 the zinc at one end with the carbon, at the other with a 
 wire. Attach a copper wire to the other zinc and another 
 one to the other carbon for the poles of the battery. 
 Use wide mouthed morphia bottles for jars for the bat- 
 tery fluid. The zincs should be amalgamated before 
 using by first washing perfectly clean, using a little dilute 
 acid if necessary, and -then rubbing them with a little 
 mercury until bright. An amalgamating fluid may be 
 made thus ; Mix one part nitric acid and three parts hy- 
 
June] PHYSICS. 419 
 
 drochloric acid by measure ;>to about one pint of the 
 mixture add an ounce of mercury. When dissolved, 
 clean and immerse the zincs until bright. Keep the fluid 
 in a glassTStoppered bottle; It may be used over again 
 as long as the mercury lasts. 
 
 15. Test the battery with the galvanometer. Wrap 
 a wrought nail or piece of soft iron wire with a coil of 
 insulated copper wire. Test the nail or wire with iron 
 filings for magnetic properties. Connect the ends of the 
 wire in the coil with the poles of the battery, and test 
 again ; what result ? Break connection, i. e., open the 
 circuit and note the effect on the filings. 
 
 16. If possible, study the mechanism of an electric bell 
 and note the battery connections. The nail with wire 
 around it, described in (15), is called an electro-magnet. 
 The electric bell is rung by means of an electro-tnagnet 
 which is rapidly magnetized and as quickly demagnetized. 
 How is this accomplished ? 
 
 17. In how many ways can you prove the presence of 
 the electric current in the wires ? 
 
 18. How can you decide as to its direction ? Since 
 the needle in the galvanometer tends to place itself in a 
 position at right angles to the course of the current along 
 the wires, can you from that fact make any inference as 
 to the force which causes the needle of the compass 
 to point north and south ? 
 
 19. How can you test the strength of an electric cur- 
 rent ? 
 
Cbemistri?. 
 
 CHLORINE. 
 
 The study of this gas will present several noteworthy 
 contrasts with those considered in the preceding months. 
 The materials needed are cheap and easily obtained. 
 The experiments are all perfectly safe, but to avoid some 
 disagreeable effects on breathing, the gas should be' 
 made where there is a good draught. The properties of' 
 chlorine are interesting and useful. 
 
 I. Place in a test tube half an inch of manganese 
 dioxide and pour upon it a little hydrochloric acid. 
 Warm gently over the alcohol lamp. What evidence 
 have you of a gas being formed ? Can you detect any 
 odor ? The gas formed is chlorine. Symbol, CI. 
 
 z. Hold in the tube moist strips of litmus paper ; 
 what takes place ? Moisten pieces of calico and hold 
 them in the fumes. Is there any change produced if the 
 articles are not moistened ? 
 
 3. Place a few small crystals of potassium chlorate in 
 a test tube, add hydrochloric acid, and test again as in (2).^ 
 Have you the same gas formed ? 
 
 4. Place in a test tube a small quantity of manganese 
 dioxide mixed with an equal weight of common salt. 
 These should be well mixed and pulverized. Mix to- 
 gether a small quantity of sulphuric acid and water, 
 equal weights of each, and pour upon the mixture in the 
 tube. Warm gently and test as above for chlorine. 
 
 5. Is chlorine heavier or lighter than air.' To collect 
 
June] CHEMISTRY. 421 
 
 this gas fit the test tube with a cork and bent tube as in 
 former experiments, and so arrange the latter that it may 
 pass through a piece of cardboard to the bottom of the 
 collecting jar, the cardboard being used as a lid for the 
 jar. Why is it possible to collect the gas in this manner? 
 Could you collect it as you did oxygen or hydrogen ? 
 
 6. ISIoisten a piece of paper with turpentine, a little 
 warm, and hang it in the vessel of chlorine ; does it re- 
 call any previous experiment ? 
 
 7. In a fresh jar of chlorine insert a candle or lighted 
 taper ; does it burn ? Does it support combustion ? 
 
 8. Place in a fruit jar a tablespoonful of sulphuric 
 acid. Sprinkle into this a tablespoonful of bleaching 
 powder, or chloride of lime, as it is also called. Cover 
 the jar with a plate or piece of glass. 
 
 9. Moisten some rose leaves and hang them in the 
 jar ; what change do you notice ? 
 
 10. Write a sentence upon a piece of paper, and, after 
 moistening it, hang it within the jar. Try a moistened 
 bit of paper with printing upon it. 
 
 u. Chlorine has a strong affinity for hydrogen. In 
 the experiment with turpentine it united with the hydro- 
 gen and left the carbon. Printers' ink being rtiade of 
 carbon, the chlorine does not affect it. 
 
 12. Chlorine is now much used in bleaching cloth, 
 paper pulp, etc. It is prepared in the form of the bleach- 
 ing powder that may be bought at the shops. 
 
 13. Bleaching powder is also used as a disinfectant in 
 sick rooms and other places. Exposed to the air the CI 
 is set free 'and unites with the hydrogen of the offensive 
 substances, breaking them up. The process is hastened 
 by the addition of a little dilute sulphuric acid. It is 
 much used in hospitals. 
 
riDeteoroIogp, 
 
 The meteorological influences of this month are usu- 
 ally benign. If the past month has supplied a liberal 
 amount of moisture, the warm sunshine, now almost 
 assured, will produce most wonderful results. 
 
 1. How many thunder showers have you noticed dur- 
 ing the past two months ? 
 
 2. From what directipn do they usually come ? 
 
 3. In what part of the day have most of them occurred ? 
 
 4. What is the ratio of rains without thunder to those 
 with it ? 
 
 - 5. Is- there any uniformity in their effect upon the 
 temperature ? 
 
 6. How long do thunder storms usually last ? 
 
 7. Have any of the storms been accompanied with 
 hail ? What was the effect upon the temperature ? 
 Examine a hailstone. 
 
 8. Has the prevailing wind been cool or warm ? What 
 is its direction ? 
 
 9. What wind accompanies a clearing sky ? A cloudy 
 sky ? The heaviest, rains ? 
 
 10. What is the rate of change in temperature ? 
 Compare with May and April. 
 
 11. Are there any fogs this month? When are they 
 formed ? 
 
 12. Have you noticed any frosts this month ? Any 
 dews ? Any nights with neither frost nor dew ? Can 
 you explain the latter ? 
 
June] METEOROLOGY. 423 
 
 13. Which are cooler, clear or cloudy days ? Why ? 
 
 14. Which are cooler, clear or cloudy nights ? Why? 
 
 15. Compare the barometric record with .that for 
 May. 
 
 16. Use the following suggestions for a summary for 
 the year : What month had the grea,test number of rainy 
 days ? The largest number of clear days ? 
 
 17. Which was the warmest month for the year ? 
 
 18. Which was the coldest month ? How far apart are 
 these extremes ? 
 
 19. Which season has the most cloudy days ? Can you 
 explain this ? 
 
 20. Do the rains of summer occur mostly in the fore- 
 noon or afternoon ? In daytime or night ? 
 
 STUDY OF SIGNAL SERVICE MAP. 
 
 21. Compare the isotherm 60 degrees this month with 
 its course and direction in May and April. Can you 
 account for any variation. 
 
 22. In what quarter of the country have there been 
 the most Low Areas ? In what quarter has there been 
 the heaviest rainfall ? 
 
 23. Are the isotherms more or less regular in their 
 course this month than last ? 
 
 24. Compare the temperature of the plain between the 
 two great mountain systems with that indicated along the 
 coast. Can you see any reason for any differences 
 noted ? 
 
 '25. Which isotherms vary most from their normal 
 course, those in the north or in the south ? Why ? 
 
 26. What isotherm this month crosses where you live ? 
 Compare with last month. 
 
424 NATURE STUDY. [June 
 
 27. Does the temperature of the Low and High Areas 
 still vary as in the preceding months ? 
 
 28. Where is the region of lowest temperature in the 
 country during this month ? Why is it so ? 
 
 29. Where is the region of highest temperature ? Can 
 you explain? 
 
astronomy. 
 
 In this month, the last of the school . year, as much 
 as possible should be done by way of comparison with the 
 different seasons. At this time another mile post of the 
 year is reached at the summer solstice, and the effects 
 should be traced as far throughout nature as the children 
 can comprehend. Children naturally seek for causes of 
 the results they see around them, and it is the principal 
 duty of the teacher to impress them with the fact that 
 the immediate causes will always be found if skill and 
 patience are observed in the search. It too often happens 
 that teachers, either through ignorance or neglect, directly 
 or indirectly impress the pupils with the notion that the 
 phenomena of nature either have no important bearing 
 upon themselves, or that they happen at random, with- 
 out direct cause. In either case the result is a grown up 
 man or woman who has not the slightest knowledge of 
 nature, or interest in the very things about him on which 
 his life depends. That the possibility still exists for the 
 public schools to produce such deformities in character 
 is a fact much to be deprecated. 
 
 1. How does the rate and direction of change in the 
 noon shadow compare with that in May ? 
 
 2. 'Compare the length of day and night in the two 
 months. Is the rate of change the same ? 
 
 3. When is the greatest variation in the day's length 
 made, at morning or evening ? 
 
 4. What angle do the sun's rays make with the earth the 
 
426 NATURE STUDY. [June 
 
 first of the month ? What is the greatest angle they make 
 during the month ? What do you notice about the length 
 of day at that time ? June twenty-first is called the 
 summer solstice, a word meaning the sun standing still. 
 Consult your noon marks for a reason for this. Can 
 you explain why the sun seems to move slowly at this 
 time ? 
 
 5. At the same date note the points on the horizon 
 where the sun rises and sets ; how far have they moved 
 since March ? Since December ? 
 
 6. Why are the days and nights unequal at this time of 
 year ? 
 
 7. At what point in the United States is there the 
 greatest inequality in day and night ? Where are they 
 nearest equal ? 
 
 8; Compare the length of day and night in the places 
 found in (7) with that of the same places in Decem- 
 ber ; explain why the case appears to be reversed at this 
 time. 
 
 9. Is there a corresponding variation between places 
 remote from each other but on the same parallel ? Can 
 you see a reason for this ? 
 
 10. In what month during the year did the shadow 
 travel farthest along the shadow-stick ? In vi^hich the 
 least ? 
 
 11. Through how. many degrees did the slant of the 
 rays, as indicated by the shadow, travel during the 
 year ? 
 
 12. In what months did the shadow stand at the same 
 place on the stick ? How did those months compare as 
 to temperature and rainfall ? Explain why the shadow 
 stands at the same place, and why the effects as observed 
 in temperature and rainfall are different. 
 
June] ASTRONOMY. 427 
 
 13. Can you now explain why we have four seasons in 
 a year ? Is it the same all over the earth ? Why ? 
 
 14. At what date was the lowest temperature reached 
 this year ? What has caused the gradual rise in tem- 
 perature since then ? 
 
 15. In what region is the greatest heat during the year ? 
 Where the greatest cold ? Why ? 
 
 16. In what region is there the greatest extremes of heat 
 and cold ? Why ? 
 
 17. Compare the plant and animal life, including man, 
 in the three regions referred to in (iz) and (13) ; in which 
 region does the greater amount of land lie ? 
 
 18. In which region is the highest civilization to be 
 found at present ? Was it always so ? 
 
 19. Suppose the earth's axis were inclined less than it 
 is, or not at all — how would it affect the climate of the 
 earth ? 
 
 20. Suppose it were inclined more than it is ; how 
 would the three regions mentioned in (14) be affected ? 
 How would the length of day and night compare with that 
 at present ? 
 
 21. Mercury appears June fifth in 1891 as a morning 
 star; how have it and the earth changed position with 
 respect to each other since it last appeared as morning 
 star ? (See Astronomy for February.) 
 
 22. How have they changed relatively since Mercury 
 appeared as evening star ? (See Astronomy for April.) 
 
 23. How does it happen that Mercury only appears 
 thus periodically as morning and evening star ? 
 
 24. Additional constellations : Cygnus in the east ; 
 southeast, Scorpio ; south, the Crow and the Crater. 
 
(Beograpbi?. 
 
 WINDS. 
 
 In the study of climate as suggested in many of the 
 preceding lessons, it has been necessary to refer to the 
 winds that are found in the different regions. Taking 
 these together, now, it will be seen that there is a simi- 
 larity between those of certain areas, though they may be 
 remote from each other. Proceeding from such general- 
 ization, keeping in mind what has been learned and 
 illustrated in Physics, pupils may in time be led to trace 
 the winds to their causes and thus get a connected view 
 of the great atmospheric movements of the earth. In the 
 same way, also, the subject of ocean currents should be 
 developed: Consult a good physical map which shows 
 the direction of the winds and currents. 
 
 1. In what portions of the globe are the great wind 
 currents the least turned from the normal course ? Com- 
 pare the land and water areas. 
 
 2. Observe the direction of the winds^ as indicated by 
 the arrows on thp map, over the Pacific Ocean within the 
 tropics ; what contrast do you find north and south- of 
 the equator as you approach the tropics ? 
 
 3. What seems to be the prevailing direction at the 
 equator? 
 
 4. Trace these winds around the globe; where are 
 they most interrupted ? Compare the Atlantic with the 
 Pacific Ocean. 
 
 428 
 
June] GEOGRAPHY. 42^ 
 
 5. Which coasts receive these winds ? This belt of 
 westerly moving winds is called the Trade Winds. 
 
 6. What is the dii-ection of the winds within the polar 
 circles ; does it appear to be uniform ? 
 
 7. Which coasts of the continents must receive the 
 polar winds? How are these winds turned from their 
 normal course ? 
 
 8. Note the direction of the arrows between the polar 
 and equatorial winds ; follow this belt around the globe 
 and notice the countries included in it. 
 
 9. These arrows indicate the place of meeting and con- 
 flict between the polar and equatorial winds ; how will 
 this interference of winds affect the climate- of this re-, 
 gion ? 
 
 10. From what you have learned heretofore (see Physics 
 for October) can you see what the great disturbing cause 
 of the atmosphere is ? 
 
 ,11. Under what conditions would there be no atmos- 
 pheric movements ? How do existing conditions differ 
 from this ? 
 
 12. What movement of the atmosphere must occur un- 
 der the vertical rays of the sun ? What is the shape of this 
 area under the vertical rays on the globe ? 
 
 13. Is the position of this belt the same throughout the 
 year? 
 
 14. How must the movement of the air in the belt un- 
 der the vertical rays affect the air lying outside of it ? 
 How, far north and south will the disturbance extend. 
 
 15. Will the air that comes from the poles be a surface 
 or an upper current ? 
 
 16. What will determine the height to which the air 
 under the vertical rays will rise ? When it ceases to rise 
 what will become of it ? What forces are acting upon it ? 
 
430 NATURk STUDY. [June 
 
 17. How will its elevation change as it moves away 
 from the equatorial regions ? Why ? 
 
 1 8. Can you now account for the" line of conflict no- 
 ticed in the temperate regions ? See (9) above. This 
 region is called the belt of Variable Winds. , . 
 
 19. What influences will tend to make it change its 
 position during the year ? At what season or seasons is 
 the wind most fickle and changeable in our latitude ? 
 Where are the rays of the sun vertical then ? 
 
 20. At what season or seasons are the winds least 
 variable ? Where is the belt of vertical rays at such times? 
 
 21. When do the warm winds prevail ? Why ? The 
 cold winds ? Why ? 
 
 22. The winds blowing from the equatorial regions 
 toward the poles are called the Return Trade Winds. 
 They descend to the surface at about latitude thirty de- 
 grees. What coasts receive these winds ? Wl^t is their 
 influence upon those coasts ? Compare the eastern and 
 western coasts of North America ; also, eastern North 
 America and western Europe. 
 
 23. What features on the surface of the globe tend to 
 change the course of the winds? Study the course of the 
 arrows near the great mountain ranges. Also near the 
 coast lines. 
 
 24. Can you see how the presence of both land and 
 water tends to deflect the, winds from the course they. 
 would take if only one were present ? 
 
 25. Which heats more rapidly under the rays of the sun, 
 land or water ? Which cools more rapidly when the sun is 
 removed ? 
 
 26. How would the winds be deflected near a continent 
 or ocean in winter ? In summer ? In the day time ? At 
 night ? 
 
Junfe] GEOGRAPHY. 431 
 
 27- Study the effect which the earth's rotation must have 
 upon the atmosphere. Turn a small hand globe rapidly 
 and hold a thread or other light substance near it ; is 
 there any evidence that the air surrounding the globe is 
 in motion ? 
 
 28. The circumference of the globe is twenty-five thou- 
 sand miles and it makes a rotation in about twenty-four 
 hours ; what is the rate of movement of a point at the 
 equator ? 
 
 29. Would a point in our latitude have the same speed ? 
 Why ? How would it be with a point on the polar circles ? 
 At the poles ? ^ 
 
 30. When the cold air start? toward the equator from 
 the poles what rotary velocity does it have ? As it moves 
 into regions having greater rotary velocity, what must be 
 the effect ? 
 
 3t. Will it at once acquire this increased velocity? 
 What must happen, then, as it advances toward the equa- 
 tor ? What direction will it have in the northern hemis- 
 phere ?. In the southern ? 
 
 32. When the air in the upper equatorial regions (see 16 
 above) starts toward the poles, wliat will be its rotary 
 velocity ? As it advances tojiigher latitude how will this 
 chaiige ? Willit acquire this less velocity at once ? What 
 will be-the effect, then, upon its direction ? 
 
 33. What is the direction of the return trades in the north- 
 ern hemisphere ? In the southern ? Where are they most 
 interrupted ? 
 
 34. What causes can you see for the oceanic move- 
 ments ? Are they in any way dependent upon the winds ? 
 Have you ever seen currents started on the surface of a 
 pond or lake by the wind ? 
 
 35. Where would the winds have the strongest effect ? 
 
432 NATURE STUDY. [June 
 
 2fi. Note the width and direction of the great equatorial 
 current and compare with the winds of the same region. 
 
 37. Note how the continents affect the direction of this 
 current ; would the earth's rotation affect currents of water 
 as it does the winds ? What shores receive the warm 
 currents ? Which receive the cold currents ? 
 
 38. Can you now understand why Europe and North 
 America have such contrasts in climate ? Compare the 
 eastern and western shores of North and South America ? 
 
 39. Is the character of a nation in any way deter- 
 mined by the winds and currents that sweep upon its 
 shores ? 
 
 40. What nations can you cite as illustrations ' 
 
(Beolog?. 
 
 SPRINGS AND WELLS. 
 
 One of the chief features of a country which will always 
 tell for or against it is the springs it affords. .Abundance 
 of pure spring water ! It is a recommendation for a place 
 which will outweigh many very disagreeable things in 
 surface, soil, or climate. Its mere mention brings up vis- 
 ions of health,-and it is indeed one of the strongest barriers 
 against pestilence and death. From earliest times, springs 
 of pure water have been objects of veneration to man- 
 kind, and they have inspired a literature, both poetry and 
 prose, that can be appreciated only by those who, having 
 once enjoyed their refreshing, have afterward been com- 
 pelled to depend upon the warm, turbid supply of cities 
 that has, too often, a doubtful origin. Common as springs 
 are in many places, they are always interesting to the stu- 
 dent,, and their ceaseless flow, year after year, is shrouded 
 in something akin- to mystery. 
 
 1. What becomes of the rain water that falls to the earth ? 
 What does the fog thaLrises after a shower mean ? What 
 does the moistened earth after the water has disappeared 
 from the surface mean ? Where does the water come from 
 that causes a stream to suddenly overflow its banks ? 
 
 2. Why does the water which comes down in a shower 
 stand longer on the surface in some places than it does in 
 others ? 
 
 3. In what kind of ground does it disappear soonest? 
 
434 NATURE: STUDY. [June 
 
 4. What determines the depth to which it must sink ? 
 
 5. Can you imagine any conditions under which the water 
 would start to flow underground ? 
 
 6. Why is it that water stands in a swamp ? Can you 
 think why it neither does not all lie on the surface nor 
 yet sink clear below it ? 
 
 7. What is necessary in order to drain a swamp ? Can 
 you think why it is that all level ground is not swampy ? 
 
 8. What kind of ground is most favorable for the passage 
 of underground waters ? 
 
 9. Would rocks be a help or a hindrance to it ? What 
 part in spring making can clay perform ? 
 
 10. When the surface water sinks to a layer of clay 
 or rock through which it cannot pass, what must then be- 
 come of it ? 
 
 11. What circumstances would favor its reappearance 
 at the surface ? 
 
 12. Can you think why it is that it appears at one point 
 instead of being spread out ? 
 
 13. It is a rule that those springs whose'flow is constant 
 throughout the year are bu-t little affected by wet or dry 
 weather. What conditions can you imagine which will ac- 
 count for this? 
 
 14. What conditions must exist underground which 
 render the flow from a spring constant and uniform in 
 amount ? 
 
 15. How must the conditions differ in those springs 
 which flow for a few days only, after a heavy rain ? 
 
 16. There are springs which flow for a time and then 
 cease for a while ; after a period of rest the flow is again 
 resumed, which is again followed by a rest. These are 
 called intermittent springs. Can you see any way of ac- 
 counting for such a flow ? 
 
June] GEOLOGY. 43S 
 
 17. The supposition has been made that such springs 
 have an outlet through a siphon-shaped tube.; will such 
 a supposition account for the facts? Make a diagram of 
 such an underground basin, with an outlet of this kind. 
 
 18. Since rain water is soft, how does it happen that 
 spring water is frequently hard ? What kinds of rock will 
 make hard water ? 
 
 19. What would be the result if the soil did not absorb 
 large quantities of water when it rains ? Of what value, 
 aside from drinking purposes, are springs ? 
 
 20. How is it that water may be obtained by boring a 
 deep hole in the ground ? 
 
 21. Sometimes, after boring a considerable depth, water 
 is obtained and it rises even with, and often above the 
 surface ; can you account for this when there is no gas 
 in the well ? What must be the character of such an 
 underground basin ? 
 
 22. Do springs ever deposit sediments about their out- 
 lets ? Where are such materials obtained ? 
 
 23. Which would be more likely to deposit such sedi- 
 ments, cold or warm springs ? Why ? 
 
 24. The light, spongy material sometimes found about 
 hot springs is called tufa. 
 
 25. Read some account of the geysers in Iceland and of 
 those in Yellowstone Park. 
 
fll>ineraIog^. 
 
 STUDY OF SOILS. 
 
 Last month directions were given for finding out the 
 mechanical constituents of soils. It will now be interest- 
 ing to study some of the physical properties of the soils 
 upon which their value to plant life depends. 
 
 1. Have you noticed any difference in soils as to the 
 rate at which they allow water to pass through them ? 
 To test this, take several glass tubes, about half an inch 
 in diameter and a foot long, and tie over one end a piece 
 of linen. Argand lamp chimneys may be used for this 
 purpose. Fill each one with a different specimen of soil 
 which has been finely powdered and well dried. Set the 
 tubes upright in a v-essel having about an inch of water 
 in it, and note the rate at which the water rises in the 
 different tubes. Keep the water at a constant level in 
 the pan by occasional additions. 
 
 2. Which soil would be best for plants ; that which 
 allows the moisture to rise rapidly or slowly ? Why ? 
 
 3. Compare the sandy with clayey soils. 
 
 4. The amount of water which soil can hold will also 
 affect the growth of plants. Illustrate the different capaci- 
 ties for water thus: Fold two filters and, place them 
 loosely, one inside the other, in a funnel. Carefully dry 
 and place on the filter an ounce of finely powdered soil. 
 Add to this cold water by drops until it begins to trickle 
 
 436 
 
June] MINERALOGY. 437 
 
 down the funnel tube. Continue to add until sure that 
 the soil is perfectly saturated and then remove the filters 
 to a piece of blotting paper or a cloth which will absorb 
 the moisture from them. Then place the under filter in 
 one scale pan and the other one, with the soil upon it, 
 upon the other, and balance with weights. How much 
 heavier is it now than the dry soil ? What per cent, of 
 its weight is water ? ^ 
 
 5. To get an id^a of the rate of evaporation from soil, 
 place the filter with the soil on it in the open air and 
 weigh at regular intervals ; what per cent, does it lose in 
 an hour ? Upon what conditions will the rate of evapora- 
 tion depend .' 
 
 6. Compare in the manner above described loam, sarnl, 
 and clay. 
 
 7. The power of soils to absorb water from the atmos- 
 phere may be illustrated as follows : Spread out evenly 
 half an ounce of carefully dried soil in a shallow tin box. 
 The lid of a baking powder can will answer the purpose. 
 Place it above a small cup of water (an individual salt or 
 butter dish may be used) and invert a jar or large tumbler 
 over both. Seal the tumbler around the edges so that 
 it may be air tight. After standing a few days weigh the 
 soil again ; has it gained any ? To what is the increase 
 due ? What per cent, is it of the weight of dry earth ? 
 
 8. Soils differ in their powers to absorb and conduct 
 the heat that comes from the sun, and they may be tested 
 in this respect in this way : Fill a large tomato can with 
 finely powdered soil ; wrap the can with several thick- 
 nesses of paper and set it in the sunshine. After a little 
 time test the temperature of the different parts with 
 a thermometer. Compare sand with loam in this par- 
 ticular. 
 
43^ NATURE STUDY. [June 
 
 9. In what kinds of soils do plants thrive best .? In 
 which the poorest ? 
 
 ID. What are the qualities- of good soil ? What are its 
 constituents ? (See Mineralogy for May.) 
 
 11. How does abundance of rainfall affect the soil? 
 
 12. Does the wind in any way affect the formation of 
 soil ?