UNIVERSITY of ILLINOIS LIBRARY at URBANA-CHAMPAIGN CURRICULUM _ Digitized by the Internet Archive in 2016 with funding from University of Illinois Urbana-Champaign Alternates X https://archive.org/details/childsbookofnatoOOhook Note. — The three parts of this hook can be had in separate volumes by those who desire it. This will be advisable when the book is to be used in teaching quite young children (from six to nine years of age), especially in schools. It will take some time to go through with each part thoroughly, and the pupil had better, for various reasons, be introduced to each in its order as a new book. THE CHILD’S BOOK OF NATURE. $jjm farts in dDnr. PART I. PLANTS. PART II. ANIMALS. PART III. AIR, WATER, HEAT, LIGHT, &c. By WORTHINGTON HOOKER, M.D. (Bill) illustrations. NEW YORK: PUBLISHED BY HARPER & BROTHERS, PEARL STREET, FRANKLIN SQUARE. 18 82 . Tgxt h /Ty THE CHILD’S BOOK OF NATURE FOR THE USE OF FAMILIES AND SCHOOLS. INTENDED TO AID MOTHERS AND TEACHERS IN TRAINING CHILDREN IN THE OBSERVATION OF NATURE. IN THREE PARTS. PART I.— PLANTS. By WORTHINGTON HOOKER, M.D., AUTHOR OF ‘‘FIRST BOOK IN CHEMISTRY,” “CHEMISTRY,” “NATURAL PHILOSOPHY,” “NATURAL HISTORY,” ETC. tBitl) illustrations. NEW YORK: HARPER & BROTHERS, PUBLISHERS, FRANKLIN SQUARE. 1882 . By Dr. WORTHINGTON HOOKER. THE CHILD’S BOOK OF NATURE. For the Use of Families and Schools ; intended to aid Mothers and Teachers in training Children in the Observation of Nature. In three Parts. Illustrations. The Three Parts complete in one vol., Small 4to, Cloth, $1 00 ; Separately, Cloth, Part I., 40 cents; Parts II. and III., 44 cents each. Part I. PLANTS.— Part II. ANIMALS.— Part III. AIR, WATER, HEAT, LIGHT, &o. FIRST BOOK IN CHEMISTRY. For the Use of Schools and Families. Revised Edition. Illustrations. Square 4to, Cloth, 44 cents. NATURAL HISTORY. For the Use of Schools and Families. Illustrated by nearly 300 Engravings. 12mo, Cloth, 90 cents. SCIENCE FOR THE SCHOOL AND FAMILY. Part I. NATURAL PHILOSOPHY. Illustrated by nearly 300 Engravings. 12mo, Cloth, 90 cents. Part II. CHEMISTRY. Revised Edition. Illustrations. 12mo, Cloth, 90 cents. Part III. MINERALOGY AND GEOLOGY. Illustrations. 12mo, Cloth, 90 cents. Published by HARPER & BROTHERS, Franklin Square, N. Y. Either of the above volumes will be sent by mail , postage prepaid , to any part of the United States or Canada , on receipt of the price. Entered according to Act of Congress, in the year one thousand eight hundrd and fifty- sevenfby Hamper & Brothers, in the Clerk’s Office of the District Court of the Southern District Court of New York. PREFACE. Children are busy observers of natural objects, and have many questions to ask about them. But their inquisitive observation is commonly repressed, instead of being encouraged and guided. The chief reason for this unnatural course is, that parents and teachers are not in possession of the information which is needed for the guidance of children in the observation of nature. They have not themselves been taught aright, and therefore are not able to teach others. In their own education the observation of nature has been almost entirely excluded ; and they are, therefore, unpre- pared to teach a child in regard to the simplest natural phenomena. Here is a radical error in education. When we put a child into the school-room, to be drilled in spelling, reading, arithmetic, ge- ography, etc., we effectually shut him in from all the varied and interesting objects of nature, which he is so naturally inclined to observe and study. These are very seldom made the subjects of instruction in childhood. And even at the fireside the deficiency is nearly as great as it is in the school-room. A similar defect appears to a great extent through the whole course of education. The study of the wonderful phenomena Vlll PKEFACE. which are all around us and within us, is, for the most part, neg. lected, except by the few whose inclinations to it are so strong that they can not be repressed. This defect is well illustrated in a remark which was made by a mother in relation to her own ed- ucation. When at school she stood at the head of her class, and excelled particularly in mathematics. Her remark was, that she every day regretted that much of the time she had given to the study of mathematics had not been spent in learning what would enable her to answer the continual questions of her children. Even when the natural sciences are taught, the mode of teaching them is generally ineffectual. The knowledge which the mass of pupils in our higher schools gain of Natu- ral Philosophy, Chemistry, Botany, and Physiology, is very de- ficient. There should be a thorough change in this respect in the whole course of education, beginning in childhood. The natural sci- ences should be made prominent among the studies even of young children, who, in other words, should be encouraged and guided in that observation of nature to which they are generally so much inclined. In the different departments of natural science there are multitudes of facts or phenomena in which children readily become interested, when they are properly explained. In this little book my object is to supply the mother and the teacher with the means of introducing the child into one depart- ment of natural science — that which relates to the vegetable world, PKEFACE. IX or vegetable physiology. With this view, I have endeavored to select those points only which the child will fully understand, and in which he will be interested. But this selection has by no means shut me up within narrow limits. I have been surprised at the amount of knowledge in this interesting study that can be satisfactorily communicated to the mind of a child. While the fundamental points in vegetable physiology are quite fully devel- oped in this book, I have avoided as far as possible all technical terms. These can be learned when the pupil becomes old enough to profit by learning them. The facts, the phenomena, are what the child wants to understand ; and these can be communicated in the simplest language, so that a child of about seven or eight, or perhaps even six years, can readily be made to comprehend them. I begin with the most simple and obvious facts — those which relate to flowers — and go on through fruits, seeds, leaves, roots, etc., step by step, until, at the latter part of the book, the circu- lation of the sap, and other points at first view complicated, are made perfectly intelligible. By this gradual unfolding of the sub- ject, many points are made clear to the child, which are not fully understood by many of those who in riper years have ' studied botany ; for in the common mode of teaching this science the mere technicalities of it are made prominent, while the interesting facts which vegetable physiology presents to us in such variety receive but little attention. The best time to use this book in teaching is during the sum- X PREFACE. mer, because then every thing can be illustrated by specimens from the field and the garden, and the teacher can amplify upon what I have given. For example, when the lesson is to be on leaves, the teacher can request her scholars to bring as many dif- ferent kinds of leaves as they can find ; and she can point out their differences after the same plan that I have adopted, but in a much more extended manner. Indeed, if the teacher catch her^ self the true spirit of observation, she will be continually led in her teachings to add facts of her own gathering to those which 1 have presented. I believe that there are few terms in the book that can not be readily understood by the child. A little explanation may some- times be necessary on the part of the teacher, especially when the same word is used as meaning more at one time than at another. For example, the word plant is used sometimes, as in the title of this book, to include every thing that is vegetable; while at an- other time it is used to distinguish certain forms of vegetables from others, as in the expression plants and trees. I have made such a division into chapters as will place each subject by itself, and at the same time, for the most part, give lessons of a proper length for the learner. I have placed ques* tions at the end of each chapter, for convenience in instruction. Of course the teacher or parent will vary them as she sees fit, to accommodate the capacities of those whom she teaches. Worthington Hooker. CONTENTS CHAPTER PAGE I. OUR LOVE FOR FLOWERS 13 II. MORE ABOUT OUR LOVE FOR FLOWERS 19 III. HOW FLOWERS ARE MADE 22 IV. THE COLORS OF FLOWERS 25 V. THE PERFUME OF FLOWERS 28 VI. THE SHAPES OF FLOWERS 31 VII. HABITS OF FLOWERS 37 VIII. MORE ABOUT THE HABITS OF FLOWERS 40 IX. WHAT LIVE ON FLOWERS 43 X. MORE ABOUT WHAT LIVE ON FLOWERS 46 XI. WHAT THE BIBLE SAYS ABOUT FLOWERS 49 XII. FRUITS 52 XIII. MORE ABOUT FRUITS 55 XIV. WHAT SEEDS ARE FOR , 58 XV. LIFE IN THE SEED 62 XVI. HOW SEEDS ARE SCATTERED 64 XVII. LEAVES 67 XVIII. MORE ABOUT LEAVES 71 XIX. THE SAP IN LEAVES 76 XX. THE USES OF LEAVES 80 XXI. LEAVES IN THE AUTUMN 83 XXII. LEAF-BUDS 86 XXIII. THE COVERINGS OF THE BUDS 90 xii CONTENTS. CHAPTER PAGE XXIV. WHAT ROOTS ARE FOR 92 XXV. MORE ABOUT ROOTS 95 XXVI. STALKS AND TRUNKS 100 XXVII. THE BARK OF TREES AND SHRUBS 103 XXVIII. THE WOOD IN TREES AND SHRUBS 105 XXIX. WHAT IS MADE FROM SAP 107 XXX. MORE ABOUT WHAT IS MADE FROM SAP 110 XXXI. CIRCULATION OF THE SAP 113 XXXII. THE SLEEP AND THE DEATH OF PLANTS 110 XXXIII. CONCLUSION 118 THE CHILD’S BOOK OF NATURE. PART I.-PLANTS. CHAPTER I. OUR LOVE FOR FLOWERS. Flowers in the garden. The garden of Eden. TpVERY body likes flowers. We like them wherever we see ^ them. How pleasant they are to our eyes as we see them in the garden ! How their various colors please us as we look along the borders! Some are red, some are white, some are blue, and some are yellow. All these different colors, mingled with the fresh green leaves, make a feast for our eyes. And then we love to look at each flower by itself. Some flowers we like better than we do others. A pretty little flower that smells sweet, we like better than we do a large one that has no perfume. The peony is very beautiful, but we do not love it as we do the little pink with its delightful fragrance. It was a garden in which Adam and Eve were placed. While they were innocent and pure God surrounded them with beautiful things, because he loved them so much. Before they sinned they lived among the flowers and trees of the garden of Eden. It was more beautiful than any garden that has been seen since that time. 14 OUR LOVE FOR FLOWERS. Flowers in the fields. The early flowers of spring. It was so beautiful that God would not let Adam and Eve stay in it after they had sinned. As we roam about the fields and the woods, it is pleasant to Jee here and there a flower. We should hardly enjoy our walk if we did not see them. They are like familiar friends that we love to meet. We see them come every year after the winter is gone, and we like to bid them welcome. A little girl, finding a wild violet early in the spring, exclaimed, “ How glad I am to see you again ! It is a long time since I have seen you, and you look as pretty as ever!” The delight expressed by this little girl is felt by every body that loves flowers, as they come one after another in the spring. How much we should miss them if they did not come every year ! The earliest flowers that we see in the spring are the most precious to us. They are very welcome, coming so soon after the cold winter is gone. They are the first children of spring. They are few. We find them only here and there. But we know that there will be many more flowers as the warm summer comes on ; and we rejoice to greet the first of the host of beautiful things that are to delight our eyes in the field and in the garden. These early flowers that we love so much are very little flowers. Look at the sweet little flowers of the trailing arbutus as they peep out from among its rough leaves. It seems as if they scarcely dared to show themselves, for fear that old winter had hardly gone. The violets too, are small, and just lift their heads from the ground. So, too, the delicate anemones, that are moved by the least breath of air, are very small. OUR LOVE FOR FLOWERS. 15 Keeping flowers in the winter. The little girl’s frozen flower. The prisoner. We are so fond of flowers that we like to have them where we can look at them in the winter. We are not willing to wait till spring comes. So we keep them in our warm rooms on stands at the windows. Those who can afford it sometimes have green- houses, in order that they may keep a great variety of plants, and have flowers all the time. People sometimes become very much attached to a few plants that they keep in their windows. Their opening flowers seem to smile upon them, and this is very pleasant to them in the midst of the dreariness of winter. It makes a little summer for them in-doors. And if the plants happen to get frozen some very cold night, it makes them feel really quite sad. A little girl became very much attached to a plant given to her by her mother. She watered it every day, and watched the buds on it as they opened into flowers. It was one of her pets. But one night it froze, and the little girl wept over her loss. She felt as if she had lost a sweet and ever-smiling friend. A kind neighbor gave her another plant of the same kind ; but it was a long time before she could feel that it was just as good as the one that she had lost. There is a beautiful story in French of a prisoner who became exceedingly attached to a flower. He was put in prison by Napo- leon because he was supposed to be an enemy of the governmento One day as Charney (for that was his name) was walking in the yard adjoining his cell, he saw a plant pushing up from between the stones. How it came there he could not tell. Perhaps some one carelessly dropped the seed. Or perhaps the seed was blown 16 OUR LOVE FOR FLOWERS. The flower in the prison. How Charney watched and guarded it. over the wall by the wind. He knew not what plant it was, but he felt a great interest in it. Shut in within those walls away from all his friends, not permitted to interest himself with eithei leading or writing, he was glad to have this little living thing to watch over and love. Every day when he walked in the court he spent much time in looking at it. He soon saw some buds. He watched them as they grew larger and larger, and longed to see them open. And when the flowers at length came out he was filled with joy. They were very beautiful. They had three colors in them — white, purple, and rose color ; and there was a delicate silvery fringe all round the edge. Their fragrance, too, was delicious. Charney examined them more than any he had ever seen before ; and never did flowers look so beautiful to him as these. * Charney guarded his plant with great care from all harm. He made a frame- work out of such things as he could get, so that it should not be broken down by some careless foot or by the wind. One day there was a hail-storm ; and to keep his tender plant from the pelting of the hail, he stood bending over it as long as the storm lasted. The plant was something more than a pleasure and a comfort to the prisoner. It taught him some things that he had never learned before, though he was a very wise man. When he went into the prison he was an atheist. He did not believe there w^as a God; and among his scribblings on the prison wall he had written, 66 All things come by chance.” But as he watched his loved flower, its opening beauties told him that there is a God. OUR LOVE FOR FLOWERS. 17 IIow the prisoner was set free. The Empress Josephine’s love of flowers. He felt that none but God could make that flower. And he said that the flower had taught him more than he had ever learned from the wise men of the earth. The cherished and guarded plant proved of great service to the prisoner. It was the means of his being set free. I will tell you how this was. There was another prisoner, an Italian, whose daughter came to visit him. She was much interested by the tender care which Charney took of his plant. At one time it seemed as if it were going to die, and Charney felt very sad. He wished that he could take up the stones around it, but he could not without permission. The Italian girl managed to see the Empress Josephine, and to tell her about it ; and permission was given to Charney to do with his plant as he desired. The stones were taken up, and the earth was loosened, and the flower was soon as bright as ever again. Now Josephine thought much of flowers. It is said that she admired the purple of her cactuses more than the Imperial purple of her robe, and that the perfume of her magnolias was pleas- anter to her than the flattery of her attendants. She, too, had a cherished flower — the sweet jasmine, that she had brought from the home of her youth, a far-off island of the West Indies. This had been planted and reared by her own hand ; and though its simple beauty would scarcely have excited the attention of a stranger, it was dearer to her than all the rare and brilliant flow- ers that filled her hot-houses. She thought a good deal, there- fore, of the prisoner that took such care of his one flower. She inquired about him, and after a little time persuaded the Emperor t B 18 OUR LOVE FOR FLOWERS. Chamey takes his plant home. Nothing comes by chance. to give him his freedom. And when Charney left the prison he took the plant with him to his home ; for he could not hear to part with this sweet companion that had cheered him in his lonely prison life, taught him such lessons of wisdom, and was at last the means of setting him free. Some, perhaps, would say that the seed of this flower got into that prison-yard, and took root in the earth between the stones by chance , and that this was all very lucky for the prisoner. But this is not so. Nothing comes by chance. God sent that seed there, and made it lodge in the right place to have it grow. He sent it to do great things for the poor prisoner. Little did Char- ney think, when he saw that tiny plant first pushing up from be- tween the stones, that by it God would free him from prison, and, what was better, deliver him from his infidelity. Questions . — What is said of our love for flowers ? Do we like some flowers better than others ? What is said of the garden of Eden ? How do we feel about the wild flowers of spring? Why do we like the earliest best? Are these large or small? Mention some of them. Why do people keep flowers in the winter in their rooms and in green-houses ? Tell about the little girl and her plant. What is the story of the French prisoner and his plant ? MORE ABOUT OUR LOVE FOR FLOWERS. 19 Bouquets. Flowers in the sick chamber. Flowers as ornaments. CHAPTER II. MORE ABOUT OUR LOVE FOR FLOWERS. It is from our love of flowers that a bouquet is always a pretty present to a friend. The kind teacher is much gratified when a scholar, with a bright, cheerful “Good morning,” gives her a bouquet. Though the flowers may be simple and common, the present is a very pleasant one. It is saying to your teacher, I love the beautiful things that God has made, and I know that you love them. It is saying more than this. It is telling your teach- er that you love her. It is because you love her that you give her the sweet flowers that you love so much. And she will feel that though the flowers will fade, your love to her will ever be fresh. Plow grateful are flowers in the chamber of sickness ! It would weary the sick one to see all her kind friends. But they can send her presents to let her know that they think of her. And what tokens of remembrance are more welcome than flowers ? Flowers are much used as ornaments, even among savages. They are more beautiful than any ornaments that man can make. What is more elegant than handsome hair dressed with flowers ? As natural flowers droop so easily, we make artificial ones for ornaments. Sometimes they are made so well that they look like fresh flowers just picked from the garden. We like flowers so much that we copy them in the figures in dress and furniture Gems and ornaments of gold and silver aro 20 MORE ABOUT OUR LOVE FOE FLOWERS. Flowers in dress and furniture. Why God has given us beautiful things. arranged in flower-shapes. Figures of flowers are seen in the pat- terns on dresses more often than any other figures. The calico- printer gets his prettiest figures from the flowers that he sees in the field an^ garden. The richest carpets are those in which the figures are flowers. We often see in the carpet under our feet a great variety of flowers of the most beautiful colors. We seem to tread on beds crowded full of roses and various kinds of flowers; and we have no fear of crushing them as when we tread on real flowers. Flowers, too, are stamped on the papers on our walls. You often see representations of flowers woven in table-cloths and napkins. You see the figures of flowers worked beautifully on articles of silver. You see them too on vases in which we put real flowers. Flowers are often carved in furniture, and even the stove-maker has them on his stoves, whether they are made for the parlor or the kitchen. Thus it is that we have flowers about us whenever we can. And where we can not have flowers, we have representations of them. I said in the first chapter that every body likes flowers. Per- haps I ought to say that almost every body likes them. A man may be so wicked and so like a brute that he can see no beauty in flowers. A man may love to hoard up money, so much, that he will not care about any thing beautiful. Some men can not see any use in flowers. They think that potatoes, and turnips, and beets, ought to grow where their daughters have their flower- garden. They forget that God has given us beautiful things for the purpose of having us enjoy them. God has a use for ev- 5 Seeds of the maple, the dandelion, and the salsify. Here is a representation of two seeds of the maple, with their wings. They always grow in this way, in pairs. Look at the little feathery ball on the stalk of the dandelion after the flower is gone. The seeds are in the middle of that ball. Pick it, and then hold it up, and blow upon it as hard as you can. Away will fly all the seeds. If the wind is blowing it will scatter them every where. Now look at them to see what makes them fly so. You see that each seed has a very little stem. This stem has on its end some very fine fibres standing out all around. The wind blows the seed about by these fibres. If the seed did not have this sort of balloon to fly with, it would fall straight to the ground. But with this it may go a great distance. Sometimes it travels over mountains and across rivers. Here is a drawing of the dandelion- seed. But to see how delicate it is, and how well fitted it is to fly, you must look at a real seed. T And here is the stem of the dande- ^ lion as it looks after the seeds are scat- tered. You see that it has a cushion- shaped end. It is on this that the seeds are fastened. It is curious to see how regularly they are arranged so as to make that beautiful feathery ball. The seed of the salsify represented here, is very much like that of the dan- i E 66 HOW SEEDS ARE SCATTERED. Seeds of the clematis. Thistle-down. Mossel and ferns delion. But the fibres by which it is carried about by the wind are, you see, very delicately feathered. The seed of the clematis or virgin’s-bower is, as you see, rather differently arranged. It has a very long stem, with little fibres standing out from it all the way, something like a feather. The down of thistles and some other flowers is the wing of the seeds by which they are scat- tered by the wind. Here is a representation i||i of a seed with its wing of down. This lit- tie seed has a very large wing to fly with. The seeds of mosses and ferns are scattered more widely than any others because they are so small. You know the mosses well. You see them every where on fences, rocks, and trunks of trees, as well as on the ground. The wind carries their fine seeds about, and they lodge on every thing. They go even to the tops of the mountains, and down into caverns in the earth. There is great variety in the mosses, and some of them are ex- ceedingly beautiful, especially when examined with a microscope. Questions— In what different ways are seeds scattered about ? What is the great scatterer of seeds ? What is said of the seeds of the maple ? What of the seeds of the dandelion ? What of the seeds of the salsify— the clematis— the thistle ? What of the seeds of mosses and ferns ? LEAVES. 67 Beauty of leaves. Variety of their shapes. CHAPTER XVII. LEAVES. Most trees and bushes are stripped of all their leaves in the autumn, and remain bare till the winter is passed. We should feel sad if they were without leaves all the year round. One use of the leaves is to gratify us by their beauty. When the winter is gone how delightful it is to us to look out upon the trees and the plants as they put forth their leaves ! Their fresh green color is a feast to our eyes. You remember what I said about the flowers having so many different shapes. The Creator has made the same variety in the shapes of leaves. He likes to make beautiful things in great variety for us to look at. Here I give you some fig- ures of leaves, to show you how different their shapes are. Here is a leaf which is row. There is a plant called arrow-head, be- cause its leaf has this shape. Here is one shaped very much like a lance, another is a good representation of a mason’s trow- el, and a third is very much like a fiddle- shaped like the head of an ar< 68 LEAVES. Various shapes of leaves. This is like a shield. The nasturtium the leaves of this kind. The stem is fastened to the leaf just where the hand holds on to a shield. This leaf has a tendril on the end of it. This clasps around whatever it happens to touch. Some plants are held up in this way by their leaves. This leaf is notched all around its edge, like a saw. The leaves of a great many plants are notched in this way, as those of the rose, the peach, and the nettle. Here is one that is notched differently. The teeth are rounded, and not sharp. It may be said to be scalloped rather than toothed. The ground ivy has a leaf of this kind. Below are two leaves, one of which is spread out like a hand, and the other is very much like the claws of the feet of some birds. The passion-flower is of the shape of the hand. So, also, is that of the castor-oil plant. LEAVES. 69 Variety in the arrangement of leaves. I have thus given only a few of the shapes of leaves. Their variety is very great. They vary not only in shape, but in color. They vary also in other things. Some have down on them, and some hairs, and some have neither. It will be well for you to see how many different kinds of leaves you can bring to the teacher, and she will tell you about them. Leaves are arranged in a great many different ways on their stems. Here are three leaves together on a stem. The leaves of the clover and the wood-sorrel are arranged in this way. Here the leaf-stem has three little branches, and each branch has three leaves. On this leaf-stem are a great many leaves. I have thus shown you three ways in which leaves are ar- ranged. But there are many other ways in which they are arranged, making a great variety in the appearance of leaves. The only way to know how very great this variety of arrangement is, is to look for yourselves at plants, and trees, and shrubs, as you walk in the garden or in the fields. Leaves are of all sizes. Some are very small, and some are very large. Look at the little delicate leaves of the chick-weed and the cypress-vine, and then at the large spreading leaves of the 70 LEAVES. Forms of leaves not commonly observed. rhubarb-plant and the pumpkin-vine, and the very long ones of the corn. The common palm-leaf fans so much in use are made from the large leaves of the palm-tree. I think that you will be quite interested in observing the vari- ous forms of leaves, though most people do not observe them much. A friend once told me that a number of leaves from our common trees were brought to some ladies, and that not one of them could tell from what kind of tree each leaf came. It seems to me that they could have used their eyes to little purpose, as they walked about among the trees of the field and the garden. They proba- bly looked at leaves merely as making a pleasant green to the eye, and never examined them, as they perhaps would flowers, to see what a difference there is between them. You had better gather some leaves of various kinds, and see if your schoolmates can tell from what trees they came. Take the star-shaped leaf of the maple, the birch-leaf with its nicely notched edges, the bright, firm leaf of the oak with its wavy edge, and the wrinkled leaf of the elm. Show them a willow-leaf beside a peach-leaf, which is very much like it. An apple-leaf and a pear-leaf togeth- er might puzzle them, though I think that some wide-awake child would see the difference between them. Questions . — What is said of one of the uses of leaves ? What of the variety in their shapes ? Mention some of these shapes. In what other things do leaves vary besides shape ? What is said of the arrangement of leaves on their stems ? What is said of their different sizes ? What is said about observing the shapes of leaves ? MORE ABOUT LEAVES. 71 Beauty of common leaves. Ribs in leaves. > CHAPTER XVIII. MORE ABOUT LEAVES. Leaves are such common things that we do not think how beautiful they are. But take any common leaf into your hand and look at it. Take the leaf of the strawberry. See how prettily it is notched. Hold it up to the light and see the lines that run from the middle line to the edge. Then see the fine net- work be- tween these lines. How delicate and beautiful ! The leaf of the raspberry is even more beautiful than the strawberry leaf, if you pick it from a new shoot. See the fine points on its edge, and see how delicate are its lines and net-work as you hold it up to the light. Observe the back of a leaf, and you will see ribs that spread out from the main rib in the middle to the edges. These are the frame of the leaf, just as timbers are the frame of a house. They are to the leaf what whalebones are to an umbrella. They give strength to it. Without them it would droop like a wilted leaf. It would not stand out straight and firm. The wind would blow it every way, like a rag tied to a stick. You see these ribs very large in broad spreading leaves. They are large in grape-leaves, and in the leaves of the rhubarb-plant, or pie-plant, as it is often called. In leaves that are very stiff and firm these ribs are so small, that at first you would say there were none. This is the case 72 MORE ABOUT LEAVES. The upper and under side of leaves. Leaves seen through the microscope. with the leaf of the pear and the orange. There is one strong rib running through in th^ middle of the leaf. But there are no strong ribs branching out from this. The leaf is so firm that it does not need them. See the difference there is between the upper and the under side of a leaf. The upper is greener than the under side. In the grape-leaf the under side is covered with a very fine white fuzz. If you tear the leaf gently, you can see the delicate white fibres of this furze across the rent. In the silver-leaf poplar there is a silvery whiteness on the under side of the leaf. This makes the tree look very pretty as its branches are moved back and forth by the wind. I have thus told you a few things about leaves. By looking at them yourselves you will see a great many things in them that will interest you. Look at them as you walk in the garden or roam in the field, and you will see that there is no end to the va- riety. And among them all you can not find one that is not beau- tiful when you examine it. Leaves are very beautiful if you look at them through a micro- scope. Take the most common leaf and look at it in this way, and you will be delighted. You will be surprised to find how much beauty there is in leaves that you knew nothing about be- fore. And now I will tell you about some leaves of a very singular character. There are some leaves that are of very singular shape. I will mention only a few. MORE ABOUT LEAVES. 73 Leaf of the side-saddle flower. Chinese pitcher-plant. Here is the leaf of the side-saddle flower, as it is called. It is shaped somewhat like a butter- boat. You see that it is open. It can hold considerable water. It lias ,a kind of lip, which looks as if it were made in order that water might be poured out of it easily. This plant grows in some parts of this country. The flower is purple, and has a curious shape. It is on a stalk that stands up in the midst of about half-a-dozen of these leaves. One of the most singular leaves is that of the Chinese pitcher- plant. At the end of the leaf the main rib extends out like a tendril, and this ends in the appendage which is represented here. It is in the shape of a pitcher, and has, as you see, a regular lid. This is generally shut down, though, as you see it here, it is raised up. The rain can not, therefore, get in, and yet the pitcher is always full of water. It holds about a tumblerful. Now how do you think this water comes there ? It is a part of the sap that comes to the leaf. The watery part of the sap is poured from thousands and thousands of little mouths on the inside of the pitcher ; and so it is kept filled with water. This plant is quite common in the island of Ceylon. There it is called monkey-cup, because the monkeys sometimes open the lid and drink the water. And men sometimes drink from these leaves when there is no spring of water where they can quench their thirst. 74 MORE ABOUT LEAVES. Venus’s fly-trap. Leaves of the fern. The leaf of the Venus’s fly-trap, which grows in North Caro- lina, is a real trap for flies and other insects. Here you see the leaf as it is spread out, wide open. It looks as if there was no danger there. But let an insect alight on the leaf, and lie is made a prisoner at once. The two parts of the leaf close to- gether, as you see, and the mSutk points on the edges are locked together, so as to furnish bars to the prison. You see a little insect caught in this leaf that had lighted only on its very edge. He can not get away, and there, poor fellow ! he must die a slow death. Of what use it is to have such traps for in- sects w T e do not understand. This is the leaf of the common fern or brake. It is beautiful if you examine it, for it is very delicate. And it has one great pe- culiarity. The flowers of the plant are on the under side of the leaf. They are where you see the little round spots. If you look at the leaf with a microscope you can see the different parts of the flowers. MORE ABOUT LEAVES. 75 Thick leaves. Live-forever. Ribbon-grass. Most leaves are thin, but some are quite thick. This is the case with the leaves of the India-rubber tree. The wax-plant has thick leaves, which, with the flowers, look so waxy as to give the name to the plant. The flowers of the cactuses grow right out from the thick fleshy leaves, making these plants look very awkward, although the flowers are so beautiful. And it is a sin- gular fact, that if one of the leaves is broken off and put into the ground it will take root and grow. Did you ever make a blow-bag, as it is called, of the leaf of the live-forever, as children very often do ? If you have not, I will tell you how it is done. The leaf is rather thick, and is made of two layers. These you can separate at the stem-end of the leaf, and then by pinching the leaf and blowing into it you can make it puff out like a bag. You must do this very carefully, or you will break the layer on the under side of the leaf, which is very thin, while the upper layer is thick. The leaf of the ribbon-grass, as it is called, is very singular in one respect. It is very prettily striped, but you can not find any two leaves that are striped exactly alike, any more than you can find two faces exactly alike among all the people on the earth. Questions . — What is said of the beauty of common leaves ? Tell about the ribs of leaves. What leaves have large ribs ? How is it with the leaf of the pear and the orange ? What is the difference between the upper and the under side of leaves ? Tell about the grape-leaf. And about the leaf of the silver-poplar. What is said of the beauty of leaves as seen through the microscope ? Tell about the leaf of the side-saddle flower. And about the Chinese pitcher-plant. Also about the Venus’s fly-trap. What is said of the leaf of the common fern ? What of thick leaves ? What of the leaf of live-forever ? What of ribbon-grass ? 76 THE SAP IN LEAVES. Wilting of leaves explained. CHAPTER XIX. THE SAP IN LEAVES. I have told you about the ribs of leaves. Let us see what makes them so firm and strong. Look at a large grape-leaf on the vine. It spreads out very firmly. If the wind blows it very hard it bends, but it stands out again as firmly as ever. But break the leaf off, and see what happens. In a little time it wilts. If you hold it up by the stem its edges droop down all around. The leaf does not stand out as it did when it was on the vine. The ribs are all there, but they have lost their strength. How do you think they lost it ? I will tell you. When you broke off the stem, the sap could no longer get to the leaf. It is just as no water can get into a house when the water-pipe is cut off outside. The sap goes to all parts of the leaf from the stem through the ribs. The ribs, like the stem, have little fine pipes in them for the sap to run in. Now, if the ribs are not full of the sap they are not firm, and they bend easi- ly. When these ribs and the net-work between them are not full of sap the leaf is wilted, as we say. But when the leaf is picked it is full of sap. How does any of the sap then get out of it so as to make it wilt? It does not leak out of the stem. If it did, you could see it drop as you hold the leaf up. Where, then, does it get out? This I will explain to you. There are little holes, or pores, as they are called, all THE SAP IN LEAVES. 77 The quantity of moisture that comes from leaves. over tlie leaf. They are so small that you can not see them with' out a strong microscope. The watery part of the sap escapes into the air through these pores. There is a great deal of moisture that comes from leaves. You can see that this is so if you put a cluster of leaves under a glass vessel. A large tumbler will answer. You will, after a little time, see the moisture in drops on the inside of the glass. This moisture is the water that comes from the pores of the leaves. You remember what I told you in the last chapter about the leaf of the pitcher-plant. The water in that leaf comes from its pores on the inside. If, instead of its having a pitcher-shape, the leaf was laid open and spread out like common leaves, the moist- ure would all go off in the air. But as it is a pitcher with a lid, the moisture that comes from all the pores is shut in. It can not fly off* in the air. And after a while enough moisture col- lects to fill the pitcher. This shows how much water common- ly goes from leaves into the air. If any leaf that you see spread out could be changed into a pitcher or cup shape with a lid, it would in a little time be full of the water that comes from its pores. Now you can understand why a leaf wilts after it is picked. It does not wilt as soon as you pick it, for the sap is all in it then. But let it be a little while. The watery part of the sap is going out of the pores of the leaf all the time, and there is no sap coming to it through the stem. So the leaf wilts. You can keep a leaf from wilting for a long time by placing the stem in water. When you do this the water goes up through 78 THE SAP IN LEAVES. Keeping flowers from wilting. Much water in the air, but not seen. the little pipes in the stem. This takes the place of the water that goes out of the pores of the leaf. When you put flowers in water, you know that the water is less the next day. This is because so much of the water goes up in the stems to the leaves and blossoms. You know that if you have a plant in a flower-pot, the earth gets dry in a day or two. This is chiefly because the water in the earth is sucked up by the roots, and runs up all through the plant, and goes out of the pores of the leaves and blossoms. Some of the water goes up directly from the earth into the air, but most of it goes through the plant. You can not see the water that comes out of the leaves and blossoms into the air. There is a great deal of water in the air that you can not see. You have often seen in a hot day the w^a- ter stand in drops on the outside of your tumbler. Just think how these drops come there. People sometimes say that the tum- bler sweats, just as if the water came through the glass. But this, you know, can not be. Water can not get through glass. The drops come there in this way. The cold water in the tumbler makes the glass very cold. And the water in the warm air around the tumbler, therefore, gathers upon it. Sometimes there is much more water in the air than there is at other times. Then the tum- bler is very wet. Now a great deal of the water in the air comes from the leaves of the trees and the plants all about us. The leaves may be said to be breathing moisture into the air all the time. I shall tell you more about the water that is in the air in Part Third. THE SAP IN LEAVES. 79 Lesson that can be learned from the leaves. This moisture that is breathed out from the leaves makes the air soft, while the fragrance of the flowers makes it balmy. Each leaf yields but a little water, and so does but little good in this way. But there are so many leaves that a great deal of water comes from all of them. It puts me in mind of the Scotch prov- erb, “Many a little makes a mickle.” Those who want to do good in the world may learn *a lesson from the leaves. A large amount of good may be done when a great many do each a little. Let those who can do but little think of this. Let them do every day what they can, just as each leaf does. Great men, that excite the wonder of the world, can do a great deal of good ; but they can not do any thing like as much as is done by a great many people together that do each a little in a noiseless way. Every child, in doing little kind things, may, like the small leaf, do his part of the good that is to be done in the world. And if much of the good that he does is not noticed by others, God sees it all, just as he sees all the moist- ure that is breathed out by each little leaf. Questions . — What makes the ribs of leaves firm ? What happens to these ribs when a leaf wilts? How does the watery part of the sap get out of a picked leaf? What is said of the quantity of water that comes from leaves ? Tell about the water in the leaf of the pitcher-plant. How does a picked leaf wilt ? How does putting a leaf in water keep it from wilting ? What makes the earth in a flower-pot be- come dry ? Can you see the w r ater that goes into the air from the leaves and other things ? Tell about water settling on tumblers in hot weather. What lesson can we learn from the leaves ? 80 THE USES OF LEAVES. Refreshing moisture from leaves. Their shade. CHAPTER XX. THE USES OF LEAVES. One use of leaves, as I told you in the last chapter, is to sup- ply the air with water. In the hot weather the air would be very dry and uncomfortable to us if the leaves did not breathe out moisture from their pores. You can see how this is if in a hot day you walk across a sandy plain where there are no leaves ex- cept those of the scanty grass and weeds. Here no moisture is breathed out upon you, to lessen the heat that you suffer from the burning sun. Another use of the leaves is this. They are pleasant and beau- tiful to the sight. I have told you about this use of them in the beginning of the seventeenth chapter. Another use of leaves is to give shade. We know how re- freshing this is to us in a hot day. When in a city we walk through streets where there are no trees, how delightful it is to come out of the blazing sun into a square that is full of trees ! How comfortable are the cows in the pasture lying under the trees at mid-day, chewing the cud ! But the shade given by leaves does good not merely to man and animals. It does good to fruits, if there is not too much of it. The sun would very often be too hot for the fruits, if it shone full on them all the time. So the leaves partly shade them. The chief use of leaves is to keep plants and trees alive and THE USES OF LEAVES, 81 The grape-vine stripped of its leaves. Leaves are lungs to plants. make them grow. If you should strip off the leaves from a plant as fast as they came out, you would, after a while, kill it. Some- times worms eat up the leaves on trees. If this is done year after year to a tree it dies. I knew a man to strip off all the leaves from a grape-vine. He thought that it would make the grapes grow finely. He had seen people take off some of the branches from grape-vines, to make the grapes grow large and full. So he thought that if he took all the leaves off, the sap would all go into the grapes and make them very large. He thought, too, that the sun would make them ripen fast. But he found that the grapes stopped growing, and wilted, and dropped off. There are two reasons for this. The sun was too hot for the grapes when all the leaves were gone. And besides, there were some leaves needed to keep the grapes alive. Leaves are the same thing to plants that lungs are to an animal. The air that goes into our lungs helps to keep us alive and make us grow. So the air that is all about the leaves of a plant or tree helps to keep it alive and to make it grow. How this is done you can not understand now. I explain it in another book, which you will be able to understand when you are a little older. There is one thing about this that you can understand, which is very curious. The air does not keep the plants alive in just the same way that it does animals. You know that by breathing air we make it bad ; and so we must have all the time a supply of fresh air. Now what do you think becomes of the bad part of the air that we breathe out from the lungs ? The leaves all around us take it in. It is good for them. It makes them and i F 82 THE USES OF LEAVES. The barter between lungs and leaves. How it is carried on in winter. the plants that they are on grow. They then, like our lungs, are all the time taking in air and giving out air. And leaves take what lungs give, and lungs take what leaves give. So lungs and leaves have a sort of trade together. They are always mak- ing this exchange with each other. And it is a good bargain for both. Both get what they want, and barter away what they do not want. But in winter, when the leaves are all gone except those on the evergreens, how is it with this trade between lungs and leaves ? Lungs are all the time giving out bad air; but there are not leaves enougli on the evergreens to take it all, and give back the good air. Well, what is to be done ? A barter is carried on with the leaves a great way off in the southern countries. The air moves about so freely that this is easily done. The bad air goes there, and the leaves that take it into their pores give out the good air, which immediately spreads every where, even to us at the north. It is a free trade — as free as air, as we may say. There is not as much bad air made by lungs in winter as in summer, because many animals are either dead or torpid. But what is made is disposed of mostly in this way. Questions . — How are leaves useful to us in giving out moisture to the air ? What use of them is next mentioned ? What is said of the shade made by leaves ? Is this shade useful to fruits ? What is the chief use of leaves ? Tell about the man who stripped the leaves from his grape-vine. How are leaves like our lungs ? What kind of barter is there between leaves and the lungs of animals ? How is this bar- ter carried on in winter ? LEAVES IN THE AUTUMN. 83 The fall of leaves. Evergreens. Change of color in leaves in autumn. CHAPTER XXI. LEAVES IN THE AUTUMN. In the autumn in cold climates the leaves fall. This is the reason that the autumn is called the fall of the year. There are some trees that have leaves on them all the time. These are called evergreens. In very hot climates the leaves of trees and bushes are out all the year round. They have no particular time to fall. And some leaves stay on for many years. Those that stay on so long grow to be very large. If a tree or a bush that has its leaves fall in the autumn in a cold climate be raised in a warm climate, it will there keep its leaves on all the year. In the southern parts of Europe quince- trees are evergreen. The currant-bush, which, you know, with us is bare through the winter, in a hot country has leaves on it all the year. Before the leaves fall, many of them, you know, become very beautifully colored. The variety of colors that you see in differ- ent trees is very pleasing to the eye. The maple-leaf is colored bright red, the oak a deep red, the walnut yellow, and other trees have their leaves variously colored. Some trees change their leaves earlier than others, and some at first are only partly changed. So you see the green mingled beautifully with the bright red, yellow, and other colors. I have often admired a single tree standing by itself when it is 84 LEAVES IN THE AUTUMN. Brilliant and varied beauty of the forests in autumn. partly changed. The maple is particularly beautiful. The top generally changes first. You often see the top bright red, and then the red is mixed with the green here and there in other parts of the tree. A little w'ay off it looks as if the top were a cluster of red flowers. And the other parts of the tree look as if the flowers were coming out among the green leaves. When the sun shines brightly all the different colors of the leaves make the woods look at a little distance as if they were all covered with blossoms. It is a very splendid sight that you see when you look off from a high hill over the woods on the hills and valleys. It looks as if monstrous bouquets of flowers had been stuck down thick together in the ground. Such a sight is especially splendid when the sun is nearly down. Then the light and shade vary the scene. Here you see the top of a tall tree standing bright in the sun, while the other trees around are in the shade. There you see a whole cluster of tall trees lighted up on one side. Here is a shaded spot, and there, close by, is a very bright spot, the sun shining upon it through some break in a hill. The colors in the lighted spots look the brighter for the shaded spots near by. So, too, it is very beautiful when, with the sun overhead, broken clouds are passing quickly in the sky. The swift shadows of the clouds give constant changes to the scene. One shadow seems to be chasing another over a bed of flowers. When the leaves put on these bright colors it is the beginning of their death. They soon fall to the ground, and decay, and be- come a part of the earth. Some one has said that flowers are LEAVES IN THE AUTUMN. 85 What makes the colors of the leaves in autumn. Forests in England. God’s smiles. So we may say that God smiles upon us in the dying leaf, when he makes it so much like a flower. How it is that all these different colors are made in the leaves in the autumn we know not. It is said that the frost makes them, but no one can tell how it does it. And, indeed, it is prob- ably not the frost alone that thus paints the leaves, for the change sometimes begins before any frost is perceived. We do not un- derstand how this effect is produced any better than we do how the various colors of the flowers are made. It is singular that in England the leaves do not appear in these very bright colors in autumn, so that an Englishman is as- tonished at the beauty of our forests in that season of the year. Now why it is that the leaves are not affected there, in the same way that they are here, we do not know. It is supposed that it is because there is more dampness there than there is with us. Whatever may be the cause, it makes a great difference with the beauty of autumnal scenery. We should hardly be willing to exchange the brilliancy of an American October day for the dull colors presented by the forests in England. Questions . — Why is autumn called the fall of the year ? What are evergreens ? What is told about quince-trees and currant-bushes ? What is said of the colors of leaves just before they fall ? Tell about the maple as its leaves are changing. How do the forests look in the bright sun when the leaves are changed ? How do they look just before sundown ? How when shadows of clouds are passing over them ? What is said about God’s making the dying leaves so much like flowers ? Do we know how the colors are made in the leaves in autumn ? What is said about the leaves in England ? 86 LEAF-BUDS. Difference between leaf-buds and flower-buds. CHAPTER XXII. LEAF-BUDS. Leaves come from buds just as flowers do. If you look at the buds in the spring on a tree you see that they are beginning to swell. They grow larger and larger, like the buds that turn into blossoms. After a while they unfold, and the green leaves are spread out. IIow is it, you will want to know, that these leaves are made ? They are very different from the leaves of the blossoms ; but, like them, they are made out of the sap. The sap comes constantly to the leaf-bud, just as it does to the flower-bud, through the fine pipes in the stem. And so this sap is made into leaves. There are, then, leaf-buds and flower-buds. You can tell them apart by their shapes. The flower-buds are round and short ; the leaf-buds are long and pointed. You can see this difference Very plainly on a peach-tree in the spring. On some trees the flower-buds open before the leaf-buds. This is the case with some of the maples. The red color that makes them look so beautiful in the spring, before they have put out their leaves, is owing to the blossoms with which they are cov- ered. These are quite small, and they are very rich, if you exam- ine them with a microscope. The flower-buds of the pencil-trees also open before the leaf-buds, and some of them are very splendid with their multitudes of pink blossoms. LEAF-BUDS. 87 Leaves and flowers from the same buds. Buds of the horse-chestnut and grape-vine. There is sometimes another kind of buds. There are buds from which both leaves and flowers are formed. You see this in the lilac. The leaves first spread out from the bud, and then in the midst of the leaves comes out a cluster of flowers. When we see all these leaves and blossoms, and remember the bud, we wonder that so much can come out of so little a bud as this was. This seems very wonderful when we see it in the horse-chest- nut. I have often watched from day to day the buds of this tree as they were opening. You see at first a small bud covered with brown scales. It grows larger and larger day after day, and after a while appears as you see it here. Soon you see it open and the leaves push out. But they are all folded up. You see them unfold more and more every day. After a while there is a tall stalk with leaves having long stems. Then comes a large cluster of blossoms at the top of this stalk. You can see the same thing in the grape-vine. The grape-stalk looks in winter as if it were a dead stick. It does not look as if any thing living could come out from it. But in the spring you see little buds starting out here and there. Watch one of these buds. You will see it swell, and after a while leaves will unfold from it. And you will see that what comes from the bud is not leaves alone. It is a branch with leaves on it. After a while clusters of blossoms ap- pear among the leaves, filling the air with their fragrance. Then grapes form. The branch goes on to grow, and gets to be many 88 LEAF-BUDS. The unfolding of plants from buds. Rock- saxifrage. feet long by the time the grapes are ripe. All this comes from the little bud, and is made out of the sap. Now suppose you could see all this happen while you stand looking at the vine. Suppose you could see the bud swell, then the leaves push out, then the flowers form, then the grapes, and then see the whole grow while the grapes are growing and ripen- ing. You would think this very wonderful. But it is just as wonderful to have all this done slowly. The great wonder is that it is done at all. No one but God could make all this come from a bud. And he could do it in an hour as well as in several weeks if he thought it was best. This unfolding of plants is very beautiful and interesting. I have often watched it in the rock-saxi- frage, one of the wild flowers of spring. I have, for this purpose, taken it up with a little earth around it, when it was nothing but a small bud peeping up out of the ground, and have put it into a saucer. As I watched it from day to day the bud spread out into leaves. Then came up a little stalk out of the midst of the cluster of leaves, and on the end of the stalk appeared a great many little white flowers. You see the same thing in the LEAF-BUDS. 89 English cowslip. The crown of the crown-imperial. English cowslip, which is represented at the bottom of the op- posite page. All this came from a little bud, just as it is with the rock-saxifrage. That curious but elegant plant, the crown-im- perial, unfolds in a little different way. A stalk comes up in the midst of the leaves ; but as it grows up leaves come out from the stalk. When it is fully grown, and in blossom, the whole plant presents a singular but splendid appearance. The long pointed leaves stand out around the tall, straight stalk for some way up. Then the stalk is naked for as much as the length of two fingers, and on the top is a crown of leaves and flowers, the flowers hang- ing down. It is very well named the crown-imperial. But there are jewels in this crown that most people do not see. They are to be seen only by looking up into the flower. In each leaf of the flower where it joins on to the stem there is a beautiful little shallow cup which is very white. From this cup hangs a shining drop, like a tear. The whiteness of the cup gives the drop a rich pearly color. It seems, as you look up into the flow- er, as if there were six splendid pearls fastened there. Each cup always has this drop hanging from it. If you put up something which will soak it up, there will soon be another one formed there. These drops are the honey of the flower. Questions . — What do leaves come from? What are they made of? How can yon tfcll the difference between flower-buds and leaf-buds? Mention some trees on which the flower-buds open before the leaf-buds. What is said about another kind of buds? Tell about the lilac — the horse-chestnut — the grape-vine. Would it be any more wonderful if the unfolding of the buds of the grape-vine were done in a siiorter time? Tell about the rock-saxifrage — the English cowslip — the crown-im- perial. What is very curious and beautiful in the crown-imperial ? THE COVERINGS OF THE BUDS. 90 Scales of the 'horse-chestnut bud. Treasures in the buds in winter. CHAPTER XXIII. THE COVERINGS OF THE BUDS. You remember that I mentioned to you the brown scales on the buds of the horse-chestnut. I will tell you what these scales are for : they cover up the tender bud from the cold of winter and early spring. These scales are quite thick, as you can see. They are glued together, too, quite tightly by a sticky substance. They make in this way a close little case for the bud, to keep it snug from the cold air. When the weather gets warm enough the swelling bud pushes the scales apart. And when the leaves are out these scales drop off, because there is no more use for them. In cold climates the buds are always protected in this way by a covering. The buds that you see in the spring do not begin in the spring. They are formed the year before, a little while before the leaves begin to fall. And as they form they loosen the leaves, and soon push them off. Now in these little buds are locked up all the leaves and flow- ers that are to come out the next spring. The precious treasures of another year are in these buds. They must be kept safe, then, through the cold winter. And so they have tight coverings to guard them from the cold. They are all this time quite small, but they are ready to grow whenever the warm weather comes. If you should pick off the covering of one of these buds in the winter the cold air would freeze it, and it would die. THE COVERINGS OF THE BUDS. 91 The care which the Creator takes of buds in the winter. These coverings have been called by some one the 4 4 winter- cradles” of the buds. It is a very good name for them. The little buds in these cradles rock back and forth in the cold winds of winter, and are as secure from harm as the little baby in its cradle in its nice warm home, shut in from the wintry blasts. And notice another thing. The inside of these cradles is lined with a soft down. This is the bud’s little blanket to keep it warm in its cradle. In warm climates the buds do not have these 44 winter-cradles,” for there is no need of them. The buds of the orange-tree and leinon-tree have no coverings. It is thus that God takes care of the tender bud. He always gives it a covering when it needs one to keep it from the cold. But in the sunny south he leaves the bud naked to the pleasant warm air. To put a thick covering over it there would do it harm. It would be like a man’s putting on a heavy overcoat in mid-summer. Questions . — What is said of the scales of the horse-chestnut bud ? What is said of the buds in cold climates ? Why is it very necessary to have the buds kept safe through the winter? What very good name has been given to the coverings of buds ? How is it with the buds in warm climates ? What is said of the care which God takes of buds ? 92 WHAT ROOTS ARE FOR. The business of roots. Mouths in their fibres. CHAPTER XXIY. WIIAT ROOTS ARE FOR. When a seed sprouts, the root, I have told you, goes down into the ground, while the stalk goes upward into the air. The root goes down because the food of the plant is in the ground. It is the business of the root to suck up this food, so that the plant may be nourished and grow. The root is, then, a sort of stomach to the plant. If it had no root it would not grow, any more than you would if you had no stomach to put your food in. The root has little mouths in its branches every where. It is by these that the food of the plant is sucked up. They are so small that you can not see them without a powerful microscope. They are in the fine parts or fibres of the root that you see hang- ing to the main branches of it when you take up a root. We are very careful not to break off these fibres when we take up a plant or tree to set it out again in another place ; for the more of these little mouths there are, the more likely will it be to live. If all the fibres be broken off from the root the plant can not live, be- cause there are no mouths to suck up the food. It will die just as you would if you should stop eating. As there are little mouths all over the fibres of a root, there must be a multitude of them. You can not count them any more than you can count the sands on the sea-shore. These mouths drink up a fluid from the ground. This fluid is the sap WHAT ROOTS ARE FOR. 93 Mouths in roots choose what they will suck up. that goes up in the stalk to nourish the plant. Every thing in the plant — the leaves, the flowers, the fruit — is made, as I have told you before, from the sap that the root sucks up. These mouths do not suck up exactly the same thing in all roots. The sap of one plant differs somewhat from that of an- other plant. What the root of a pepper-plant sucks up is not the same that is sucked up by the root of a strawberry-plant. The root of the pepper-plant sucks up such sap that the biting peppers can be made out of it. And the root of the strawberry-plant sucks up sap that is fitted to make its pleasant fruit. The pepper-plant and the strawberry-plant are so different from each other, that we should hardly suppose that they could grow out of the same earth side by side. But they can. How is this ? Do the little mouths in the roots choose their food ? They do. The strawberry mouths choose what will make strawberries, and the pepper mouths choose what will make peppers. But they do not choose in the same way that we choose. They do not think about it as we do. But they choose just as well as if they did think. Perhaps they choose better than we do. We sometimes make mistakes about our food. But they always choose just right. How this is we do not know. God has made them in such a way that they suck up the right kind of food from the earth. This is all that we know about it. Very commonly different kinds of plants will grow in the same kind of earth. What a variety of plants and trees you often see in the same garden ! But sometimes one plant requires a differ- ent soil from other plants. You see this in the asparagus. This 94 WIIAT HOOTS ARE FOR. Asparagus roots like salted food. Flowers in swamps. vegetable does best in a soil that has considerable salt in it ; that is, it thrives on salt food, as we may say. For this reason we sprinkle salt over an asparagus-bed in the spring. But while salt makes the asparagus grow so well, it will kill other plants. It will kill all the weeds and grass that happen to be in the asparagus-bed. If you put on a good deal of salt no weeds will come up till after all the salt is sucked up by the aspar- agus. I had a chance last spring to see how bad salt is for grass. The man who put the salt on my asparagus-bed spilled some of it on a grassplot close by. In every spot where it fell it killed the grass. So you see that what is poison to grass is food to as- paragus. We find some kinds of flowers only in swamps. These will not grow well in the high grounds where the soil is different. The reason is, that the little mouths in the roots do not find the right kind of food there. Questions . — How is the root a sort of stomach to a plant? Where are the little mouths of the root ? What is said about care in moving plants or trees ? What is said of the number of mouths in a root, and of their size ? Do the roots of the pepper-plant and the strawberry-plant suck up the same kind of food ? What is said of the mouths of roots choosing their food from the ground ? Tell about the asparagus. What is said of plants growing in swamps ? MOKE ABOUT ROOTS. 95 Branching roots. Fibrous roots. CHAPTER XXY. MORE ABOUT ROOTS. The root, "besides being a sort of stomach to the plant, is its support. The plant is fastened by it firmly in the ground. For this reason a large tree has a large and deep root. Its root branches out very much as the tree does above. It is shaped as you see here. But when the plant is quite small, and there is not much to be supported, the root is different. It is perhaps made up of fibres as seen in this figure. This is the case with the roots of grass, as you can see by pulling up some of it. In a piece of turf there are a great many spears of grass, and so it is full of these fibrous roots mingled together. Some roots are made for still an- other purpose. Besides nourishing 96 MOKE ABOUT ROOTS. Beets and turnips. the plant and supporting it, the root sometimes answers for food. When a root is intended for this use it is large. Look at the root of the beet. Here is a figure of it. The leaves, and with a very small root it would stand up in the ground. A small root, too, would answer to suck up all the sap that it needs. So small a plant could get along with a very small stomach. you that the seed-holder is sometimes larger than it need be to hold the seeds. The pear is a seed-holder, but it is larger than it need be if it were meant to be only a seed-holder. It is meant to be something else. It is fruit to be eaten as well as a seed -holder. It answers two purposes. So, too, when a root is larger than it need be to nourish the plant, it answers two purposes. Besides sucking up food for the plant, it answers as food for animals. In these large roots the mouths that suck up the sap are not in the body of the root. They are in the little fibres that are joined on to the main root, as you see in the beet. In the root of the turnip, as seen in this figure, there is a sort of tail going down into the ground from the bottom of it. The fibres, where the mouths are, make a part of this tail. plant does not need so large a root as this to nourish and support it. The plant is nothing but a bunch of You remember that in the chapter on seeds I told MORE ABOUT ROOTS.' 97 Runners. Roots of dahlias. Bulbs. In some plants roots are formed very curiously. Shoots start out and run along on the ground. After a little while these run- ners, as they are called, send dowm roots into the ground, as is here repre- sented. The strawberry, you know, spreads in this way. So do the verbenas. When a runner gets fairly rooted it can live by itself, for it has a root, that is, a stomach of its own. You can separate it now from the main plant if you choose, and set it out somewhere else. This is done whenever we plant a new strawberry-bed. This is a singular kind of root. It is spread out like a hand. Each of these fingers can be separated from the rest, and will grow by itself. The roots of the dahlias are of this kind. Some roots are bulbs, as they are called. The onion is a bulbous root. Below is one cut open. You see that it is all made up of coats, one inside of another, which you can peel off. The roots of hyacinths, lilies, blue-bells, and crocuses, are bulbs. These lie in the earth very still through all the winter. The life in them is asleep, just as it is in the buds. But it wakes up in the spring, and down go the roots from the bottom of the bulbs, and up come the plants from their tops. It is sometimes said that a bulb is really a bud, only it Gr 98 MORE ABOUT ROOTS. Slips of plants. Duck- meat. is in the ground, instead of being in the air as most buds are. Thus the onion is a bud, and the real roots of the plant are what you see branching down from the bottom of the bulb. You have heard people talk about setting out slips. A slip is a branch of a plant. Some plants will grow from slips. Gera- niums will. If you put a slip of geranium into the ground and keep it well watered, a root will shoot down into the earth from the end of the stem. And so the branch cut off becomes a grow- ing plant. Before it was cut off it got its food with the other branches from the root of the plant to which it belonged. After it was cut off it could not live unless it could get a root of its own to suck up its food from the ground. Most plants get their food from the ground. But some do not. Some get their food from water. This is the case with a plant called duck-meat, that is found in ponds and ditches where the wa- ter is still. You see little leaves on the surface of the water, and the roots hang like -P=- threads from the leaves. This is repre- sented in this figure. Now there is some- thing in the water in these places which is sucked up by these roots and makes the leaves grow. Sea-weed has no roots extending down into the ground, but it gets its nourishment from the water. There are some plants that live on other plants. The mosses that you see on trees are plants of this kind. At the South there is a kind of gray moss that hangs down from the branches of trees, sometimes to a great length. It makes the land look as if MORE ABOUT ROOTS. 99 Hanging moss. Dodder, or love-vine. it were bung in mourning. The sap that nourishes this plant it gets from the bark of the trees. There are mouths in the moss where it hangs from the tree that suck in the sap which they find there. The dodder, or love- vine, is a curious plant. It lives on other plants. It comes up out of the ground and clings to any plant that happens to be near it. After it is well fastened, and has grown considerably, its root in the ground dies. The little vine does not need it any longer, for it clings by real roots to the plant up which it runs. This is the reason that it is called love-vine ; for, like love, it lives on that to which it clings. This vine has no leaves, and it is of a bright-yellow color. So it is sometimes called gold-thread vine. Questions . — What is said about the root as a support for a tree ? How is it with the roots of grass? What is said about roots that are for food? Tell about the root of the beet. Give the comparison made between roots and seed-holders. What is said of the root of the turnip ? What of the roots of strawberries and verbenas ? What of the roots of dahlias ? What is said of bulbs ? How do plants grow from slips ? What is said about the duck-meat ? What is said of mosses ? Tell about the dodder. 100 STALKS AND TRUNKS. Trunks of trees. Stalks of grain and grass have flint in them. CHAPTER XXVI. STALKS AND TRUNKS. We speak of plants as having stalks, and of trees as having trunks. A tree has a stout firm trunk, "because its top is so large and heavy. Its branches spread out so much, that the tree would be broken down by the wind if it did not have a strong trunk. It is the woody part of the trunk that is so strong. The stalks of plants have no wood in them, because they do not need it. They are strong enough to support the branches without having any wood in them. Some plants have their stalks made strong in a singular way. There is a flinty earth in them. This is the case with wheat, and rye, and most kinds of grass. See how tall the stalk of rye or wheat is. And it is very slender. But as the wind bends it over it does not break, because the flint in it makes it so strong. It is this flint in different kinds of straws that fits them to be used in making hats and bonnets. They would not be firm enough for this use if there was no flint in them. You can not see or feel the flint in the straw. The reason is, that the particles of the flint are so fine, and are so well mixed up with the fibres or threads of the straw. It is this fine flint in straw that makes its ashes so useful in polishing marble. In some plants you can feel the roughness that is made by the flint. You can feel it in the scouring-rush, which is sometimes used by house- STALKS AND TKUNKS. 101 How flint gets into stalks. Shrubs. Vines. keepers in scouring. In this there is more of the stony substance than there is in the straw of your hat, and it is not as fine. But you will ask how stone or flint gets into these plants. It is sucked up from the ground by the mouths in the roots, and it goes up in the sap to where it is wanted. It is wanted in the stalk of the grain, and so it stops there. It never makes a mis- take by going into the kernels of the grain. If it did, the flour that is made from them would be gritty, as we should find out when we came to eat the bread. All plants that have no wood in their stalks die down to the ground in the autumn, though the roots of some of them live through the winter. But trees, you know, remain from year to year. So do shrubs and bushes. These may be considered as little trees. Some shrubs are so small that they do not need to have their stalks woody merely to support the branches. Thus the currant-bush could have its branches well supported if the stalks were not woody. In such cases the stalks are made woody so that they may last over the winter. Stalks and trunks commonly stand up of themselves. But there are some that can not. When this is so we call the plant a vine. Vines are supported in various ways. Some are held up by merely winding around something. This is true of the bean- vine. It winds itself, as it grows, around the pole that is put up for it. The hop-vine is supported in the same way. It is, you know, quite rough, and so it can cling firmly even to quite a smooth pole. Pea-vines are held up in a different way. Little tendrils are 102 STALKS AND TRUNKS. Tendrils. Thunbergia. Trumpet-creeper. put forth which wind around the branches of the bushes that are set for the vines to run up on. These tendrils clasp very tightly. You see them on many kinds of vines. You see them on grape- vines, and on the vine of the passion-flower. Sometimes the ten- drils go out from the ends of the leaves. You see a leaf of this kind on page 68. A vine called thunbergia is held up in a very queer manner. If a leaf happens to come near a twig or a string it twists its stem around it. So the stems of the leaves act as tendrils to support the vine. The vine of the trumpet-creeper is supported in a singular way. Whenever it touches any thing there come out at the joints of the stalks some sprawling things like the feet of a spider. These feet fasten themselves very strongly to whatever the vine is run- ning on. If it runs up the side of a board fence, these feet mix up their fibres very tightly with the fibres of the wood. It is curi- ous to observe that where any part of the vine is not against any thing these feet do not appear. They are made only where they can be used. The plant acts just as if it knew where it could use them. Questions . — What is the difference between stalks and trunks ? Why does a tree need so strong a trunk? Why do the stalks of plants have no wood in them? What is said of the flinty earth that is in some of them ? In what ways is the flint in straws of use ? What is said of the scouring-rush ? How does flint get into any plant? Why does it not go into the kernels of grain as well as into the stalks? What becomes of stalks that are not woody in the winter? What is said of the woody stalks of shrubs ? What are vines ? How is the bean-vine supported ? Tell about tendrils. What is said of the thunbergia? Describe the way in which the trumpet-creeper is supported. THE BARK OF TREES AND SHRUBS. 103 The outer bark of a tree its coat. CHAPTER XXVII. THE BAEK OF TEEES AND SHEUBS. In the trunk of a tree or the stalk of a shrub there are three parts. They are the bark, the wood, and the pith. The bark is not all one thing. It is made up of two parts ; or rather, we should say, there are two barks. There is an outer bark and an inner one. The outer bark has no life in it. It is this outer bark that gives such a roughness to the trunks of some trees, as the elm and the oak. In the birch, you can peel off this bark in strips right around the trunk of the tree. Indians make very pretty boxes of these strips of birch-bark. The outer bark is a coat for the tree. It covers up the living * parts so that they shall not be injured. It does for the tree what our clothes do for our bodies. It is not a perfectly tight coat. It has little openings every where in it. It would be bad for the tree to have this coat on it tight, just as it would be bad for our bodies to have an India-rubber covering close to the skin. This outer bark is a great protection to the tree through the cold winter. It keeps the cold from killing the trunk and the branches. This coat of the tree covers it all, even out to the end of the smallest twig. The tree looks as if it was dead in winter without its green leaves. But there is life locked up there, just as I told you there is in the seed that is kept through the winter. The life in the tree is asleep as it is in the seed. It is ready to 104 THE BARK OF TREES AND SHRUBS. The inner bark. Trees sometimes covered with straw in winter. be waked up when the warm weather of the spring shall come. During this winter’s sleep of the tree, the living inner bark and wood are safe, covered up by the tree’s rough coat. If you peel off the outer bark, as you can very easily in the birch, you come to the fresh and juicy inner bark. This I have told you is alive. It is full of sap. It has a great deal to do with the growth of the tree. It is by this bark that the wood in- side of it is made. You have sometimes seen small trees covered in the winter with straw tied nicely all around them. This is because they are tender trees that are not used to our cold weather. They belong to a warmer climate, and God gave them just such a coat as they needed there. And when we undertake to have such trees here at the north, the coat that God has given them is not enough to keep them from freezing in our long, cold winters. So we have to put another coat over it. Questions . — What are the parts of the trunk of a tree? Tell about the bark. What is the outside hark for? How much of the tree does it cover and protect? What is said of the life asleep in the trees in the winter ? What is said of the in- ner hark ? Why is straw tied around some trees in winter ? THE WOOD IN TREES AND SHRUBS. 105 How wood is made. Its layers. Pipes in the wood for the sap. CHAPTER XXVIII. THE WOOD IN TREES AND SHRUBS. Perhaps it seemed strange to you wlien I said in the last chap- ter that bark makes wood. But so it is. Every year the living inner bark goes to work and makes a layer of wood out of the sap that is in it. This work is done in the warm weather. In the winter there is no wood made. The tree is asleep then. It is what the bark does that makes the tree larger every year. A new layer of wood is formed by it all up the trunk, and along out to the end of all the branches. The different layers of wood made in the different years are often very distinct from each other. You can see them in a log that has been cut or sawn across. Sometimes they are so dis- tinct that you can count them, and so tell just how many years old the tree is. Here is a representation of the sawn end of the trunk of a tree. You see that the rings of the wood are very plain. The wood part of the trunk and branches is full of small pipes. It is through these pipes that the sap goes up from the roots and gets to the leaves. It is in this way that it goes to the very ends of the topmost boughs of the tallest trees. This is very wonderful. How the sap is made to go up such a great distance 106 THE WOOD IN TREES AND SHRUBS. Sap-pipes numerous. Heart-wood. Pith. through these pipes in the wood we do not know. There is only one way that man can make water go so high through pipes. He can do it by a forcing-pump. But we can see nothing like forcing- pumps in the trees. We find nothing but these pipes going from the roots up to the leaves. And the sap is flowing up through them very quietly all the time. In a large tree there is a multitude of these pipes in the "wood. And when you look at the huge trunk, think what a quantity of sap there is going up through it all the time to keep all those leaves fresh and green. If you could see it all in one pipe it would be quite a stream. If you look at the end of a log you will see that there are two kinds of wood. The wood in the centre is different from that which is around it. It is called the heart-wood. The pipes in it are stopped up, and no sap can go up through it. The pipes for the sap are clear only in the newest part of the wood. The use of the pith of trees and plants we do not understand. The pith is very small in trees, but it is quite large in some plants and shrubs. All boys know that it is very large in the elder. It is also large in the stalks of corn, and of the sugar-cane. Questions . — How is the wood in a tree made ? What is said of the different lay- ers of wood ? What is said of the small pipes in the wood ? Do we know how the sap is made to go up in them ? What is said of the quantity of sap that goes up in the trunk of a large tree ? What is said of the two kinds of wood that you see in looking at the end of a log ? What do we know about the pith of trees and plants? WHAT IS MADE FROM SAP. 107 The great difference in things made from sap. CHAPTER XXIX. WHAT IS MADE FROM SAP. Every thing that you see in a tree or a plant is made from the sap. The bark, the wood, the leaves, the flowers, the fruit, are all made from it. Even the root that sucks up the sap from the ground is made from the sap itself. It is strange that so many different things can be made out of the same thing. It is strange that a rough bark and hard wood can be made from the same thing as the beautiful flower and the delicious fruit. Look at an apple-blossom, and then look at the bark of the tree, and think of them as being made from the same sap. You can hardly believe that it is so. How strange it is to think of the sharp thorns on a rose-bush as being made from the same sap that makes the soft, and smooth, and beautiful leaves of the roses ! If any man should tell you that he could make a brick and a piece of cloth, with beautifully colored figures on it, from the same thing, you would say he was crazy. But there is not as much difference between the brick and the cloth as there is be- tween rude bark and a flower made from the same sap. The Creator does, in the most common plants and trees, what man can not equal in any way. There are some things made from sap that I have said nothing about as yet. There are many bitter, and sweet, and sour things 108 WHAT IS MADE FROM SAP. The sugar-cane. How the sugar is obtained from it. made from sap. Sometimes sweet and bitter things are made at the same time from the same sap. You see this in the orange. From the same sap that comes to the orange through the stem are made the sweet juice and the sharp and bitter peel. Almost all our sugar comes from the sugar-cane. This is shaped like the stalks of corn. The sugar is made from the sap that comes up in the pipes of the cane from the ground. The cane, then, is really a sugar-factory. Man does not make the sugar, but it is made for him in the cane. It is in the juice of the cane. This juice is mostly sugar and water. In making sugar, as it is called, the sugar is not made. It is only separated from the water and other things with which it is mixed in the cane. The sugar is made from the cane in this way. The cane is cut into pieces, and these are put into a mill where they are pressed between iron rollers. The juice squeezed out in the mill runs off into a large reservoir or tub in the boiling-house. It is now put into boilers and boiled down. In this boiling the water goes off in steam, but the sugar remains. When it is boiled down to a sirup it is put into very large wooden trays called coolers. Here the sirup becomes sugar, because the rest of the water goes off in the air. The way in which sugar is made perfectly white, it is said, was discovered in a curious way. A hen that had gone through a clay mud-puddle went with her muddy feet into a sugar-house. She left her tracks on a pile of sugar. It was observed by some one that wherever her tracks were the sugar was whitened. This WHAT IS MADE FROM SAP. 109 IIow a discovery was made about whitening sugar. led to some experiments. The result was, that wet clay came to be used in refining sugar. It is used in this way. The sugar is put into earthen jars shaped as you see the sugar-loaves are. The large ends are upward. The small ends have a hole in them. Here is a picture of one of these jars. The clay is put on the top of the sugar in the large end of the jar, and it is kept wet. The moisture goes down through the sugar, and drops from the hole in the small end of the jar. This makes the sugar perfectly white. This discovery shows how much a little looking and thinking will together do. What the hen did was a small thing. One would hardly suppose that any thing could be learned from a hen’s tracks. Most people would have scraped off the mud from the pile of sugar, and thought nothing more of it. But the man who saw the tracks was in the habit of thinking about what he saw. And so he discovered in that hen’s tracks a very useful fact. If you always think about what you see you may some time be a discoverer too. At any rate, that is the way to learn. And it is to help you in learning to think about what you see that I have written this book. Questions . — What things are made from sap? Mention some things very differ- ent from each other that are made from the same sap. Give the comparison about brick and cloth. What is said about the orange? What about the sugar-cane? How is sugar made from the sugar-cane ? Of what use is the boiling ? Tell liow one way of purifying sugar was discovered. What does this discovery show? 110 MORE ABOUT WHAT IS MADE FROM SAP. Maple- sugar. The sugar-cane. Some plants sugar-factories. CHAPTER XXX. MORE ABOUT WHAT IS MADE FROM SAP. You have eaten maple-sugar. This comes from a tree called the sugar-maple. The sugar is in the sap, just as it is in the case of the sugar-cane. The sap is obtained early in the spring by tapping the trees, and then it is boiled down, as it is called. In this boiling the water goes off in steam and the sugar re- mains. The sugar-maple, then, is a sugar-factory as well as the sugar-cane. There are many roots in which there is sugar. Sugar has often been obtained from a kind of beet called the sugar-beet. There is sugar in many fruits, making them sweet to the taste. Now where does the sugar in the sugar-cane, the maple, the beet, etc., come from ? The sap in which the sugar is comes up from the roots. You will say, then, that the little mouths in the roots suck up sugar from the ground. But there is no sugar in the ground. No one ever found any there. Take up a hand- ful of earth, smell of it, and taste of it. There is no sweetness in it. Though there is no sugar in the ground, what the sugar is made from is there. This the little mouths in the root drink up, and it is made into sugar in the plant. You see, then, how true it is that the plant is a sugar-factory. Now do you think that any man could in any way make sugar MORE ABOUT WHAT IS MADE FROM SAP. Ill Plants make starch, medicines, gums, and perfumes. from the earth under his feet ? He can no more do it than he can make a flower or a leaf. There are a great many other things made by plants from Avhat they suck up from the earth. I will mention some of them. Some plants are starch-factories. They make the starch from the sap that comes up from the root, just as the sugar is made. There is starch in every kind of grain, in potatoes, and in many other roots. Some plants are medicine-factories. Camphor is obtained from the bark and wood of a tree. Opium is found in the different kinds of poppies. There are various bitter medicines that are found in different plants. Castor-oil is obtained from the seeds of a large plant. These, and various other medicines, are made from sap. Some plants are gum-factories. You have sometimes seen gum on the bark of peach-trees and cherry-trees, when the bark has been wounded in some way. Now there are some kinds of trees in which there is a great deal of gum. The India rubber is a gum that is obtained from some kinds of trees in warm climates. When the bark of these trees is wounded this gum oozes out. It is collected as it flows. It is dried in smoke, and this gives it its dark appearance. Many plants are perfume-factories, as I told you in Chapter Y. The perfumes are made most often in the flowers, but they are sometimes made in the leaves and other parts. You know how fragrant the leaves of the geranium are. Even wood is some- times fragrant. The sandal-wood is very much so. 112 MORE ABOUT WIIAT IS MADE FROM SAP. The great variety of things made from sap. Some plants are color-makers. They not only make colors for their own use — that is, to color their flowers — but they make them for us to use. Many of our dyes with which we color cloths come from plants. They are made in the plants from the sap that comes up from the ground. It seems strange that the blue indigo should be made out of what a plant drinks up from the brown, dull earth. But so it is. Now just think over the various things that are made from the sap in plants. There are wood, bark, leaves, flowers, fruits, thorns, perfumes, colorings, sugar, starch, gum, various medicines, etc. And then there are many other things that I have not men- tioned. How strange it is that so many and such different things can be made from what the plants suck up out ot the earth ! As you look at the ground under your feet, you can hardly believe that so much can be got out of it. It is the busy little mouths in the roots that get from it w T hat is needed to make all these dif- ferent things. Questions . — What is said of the sugar-maple? What is said of sugar in some roots and fruits ? As there is no sugar in the ground, how does it get into plants ? Can any body make sugar from earth ? What plants are starch-factories ? Men- tion some medicines made in plants. What is said about plants that are gum- makers? What is said about perfumes being made in plants? What about colors? What is said about indigo ? Mention now all the things that you can think of that are made from the sap in plants. CIRCULATION OP THE SAP. 113 The difference between the sap that goes up and that which comes down. CHAPTER XXXI. CIRCULATION OF THE SAP. I HAVE told you that the sap goes up in a plant or a tree in certain pipes. Now when it gets to the leaves it turns about and goes back again down toward the ground by some other pipes. So there is a set of pipes for the sap to go up, and a set of pipes for it to go down. In a tree, the pipes for it to go up are in the wood. Now where do you think the pipes are for it to go down ? They are in the live part of the bark. The sap is all the time going up to the leaves in the one set of pipes, and com- ing down in the other set. And this is what we call the circula- tion of the sap. The sap that goes up has a great deal of water in it. Much of this water is got rid of when the sap comes to the leaves. You remember that I told you, in the chapter on leaves, that water is let off into the air from their pores. For this reason the sap that comes down from the leaves has much less water in it than the sap that goes up. The sap that goes up is not perfect sap. It has to make a visit to the leaves and get an airing there before it can be of much use. After it is aired it goes to all parts of the plant, down to the very roots. It is this aired sap from which generally every part of the plant grows, or is made. You remember that I told you in the last i H 114 CIRCULATION OF THE SAP. The airing of the sap. The sugar made from the sugar-maple. chapter that in trees the inner bark makes a new layer of wood every year. Now the bark makes the wood from some of this aired sap as it goes down in the pipes of the bark. You remember that I told you in the chapter on leaves, that they have much to do with the growth of a plant. You can now see why this is so. The sap has to go up to the leaves to be made good sap. Just what the air does to it there you are not yet old enough to understand. But after a little time you will be able to understand this, and then you will see that leaves are very properly called the lungs of plants, and that they breathe with them as we do with our lungs, though in a different manner. I have said that the sap that goes up is not of much use, and that every thing in the plant is made from the sap that goes down. This is not always so. In the sugar-maple it is the sap that goes up in the early spring that has the sugar in it. The sugar-gatherers tap the trees before the leaves are put forth. The leaves, then, have nothing to do with making the sugar. How it is made we can not understand. We suppose that it is done in the root, where the mouths are that drink up the sap from the earth. But though we do not know how it is, in some way every sugar-maple as soon as it begins to be warmed by the air of spring becomes at once a sugar-factory. Though most of our sugar comes from the sugar-cane of south- ern climates, a great deal is made from the sap of the sugar-maple in some parts of the northern and western states in this country. A very busy time they have in some places in the early spring in collecting the sap and in boiling it down. The sirup is often sold CIRCULATION OF THE SAP. 115 The sap always in motion except in winter. as maple-sugar molasses. But more often it is made into sugar ; and great quantities of it are sold every year. In some places where it is made many of the people use no other sugar. The sap is all the time in motion in the trees and plants in all the warmer months of the year. It is always going up and com- ing down. It does so till the leaves fall and the cold of winter comes. Then all this motion stops. And through the winter the sap is almost as still as if the trees and shrubs were dead. Then when the spring comes, the mouths in the roots begin again to suck up sap from the ground, and it runs up and down in the little pipes as it did the year before. As you look at all the trees and plants about you, think how much sap there is running up and down in their pipes. Look at a very large tree, and think of this. In multitudes of pipes in that huge trunk the sap goes up to the very end of all the branch- es to the leaves, and then it comes down in other pipes. How wonderful this is, and yet how few there are that ever think about it ! Questions . — Where are the pipes in which the sap goes up in a tree ? Where are the pipes in which it comes down ? What is said about the water in the sap ? What becomes of a part of this water ? Why is it necessary for the sap to go up to the leaves ? Are things made from the sap that goes up, or that which comes down? How is it with the sugar in the maple? Where is its sugar made? Is the sap al- ways in motion? 116 THE SLEEP AND THE DEATH OF PLANTS. Most plants die in the fall. How trees sleep in the winter. CHAPTER XXXII. THE SLEEP AND THE DEATH OF PLANTS. When the cold weather comes some plants die, and some go to sleep for the winter. Some plants always die in the fall. Corn dies ; so does the bean-vine. And so do many other plants. In order to have such plants another year, we keep some of their seeds to put into the ground in the spring. But some plants sleep in the winter. Look at a tree. Its branches are all bare. It seems as if it had no life in it. But there is life there, and it will show itself next spring. Its life is asleep, just as I told you it is in the seed before it is put into the ground. Its sap is all quiet in the pipes. The mouths in the roots have stopped their busy work. The buds all over the tree are asleep in their “ winter-cradles.” The wind rocks them back and forth, but never wakes them up. How much life there is asleep in that tree ! The buds are all there which are to make all that you will see on it the next sum- mer. They are covered up snugly from the cold in their winter coats. The little things are very still, but they are alive. They only want a warm sun to make them show it. As soon in the spring as they feel the warmth through their coats, they begin to swell, as I have told you in another chapter, and soon open their coats and go to work to make leaves, a^l flowers, and fruits. A THE SLEEP AND THE DEATH OF PLANTS. 117 Life asleep in roots. Decay of leaves and plants. great work they do after their long winter sleep. Look up into a tree in summer and see how these leaf-buds have filled every branch with leaves. You can hardly believe that it is the same tree that you saw so bare in the winter. Some plants die down to the ground, and their roots live through the winter. You know that this is the way with tulips and daffodils. They come up in the spring from the roots that have been in the ground all the winter. So, too, do the beautiful crocuses, that peep up so early in spring that they often get cov- ered with snow. The roots of grass, too, live in the earth through the winter. The life in these roots is asleep through the winter, just as it is in the trees and bushes. Their little mouths do not drink up any sap. How much life there is asleep in the winter covered up in the earth ! What do you think becomes of all the leaves that fall, and of all the plants that die in the autumn ? They are not lost. They decay and become a part of the earth. A great deal of the ground under your feet was once in the shape of stalks, and leaves, and flowers. And now the roots suck up from it sap to be made into the same shapes again. So you see that the dead plants and leaves of one year are used in making the plants and leaves of the years that come after. Questions . — What is said of plants that die in the fall ? Tell how it is with a tree in the winter. What does the warm weather do to its buds in the spring ? Men- tion some plants that die down to the ground in the fall, but whose roots live through the winter. What is said of the life in these roots ? What effect does the spring have on them 9 What becomes of all the leaves and plants that die in the fall? # 118 CONCLUSION. Knowledge of nature increases our enjoyment of it. CHAPTER XXXIII. CONCLUSION. So I have told you in this book many things about trees and plants. And I suppose that you will look at them with more pleasure now than you did before you knew so much about them. Almost every body says when looking at a handsome plant or tree, how beautiful it is ! But you will say something more than this. You will say how beautiful and how wonderful too ! You think of the sap going up and down in the pipes, of the busy mouths in the roots drinking it up from the ground, of the many different things that are made from the sap, of the beautiful leaves acting as the lungs of the plant, and of the leaf-buds from which the leaves are made. And because you know something about all these things, plants and trees look more beautiful to you than they ever did before. You have always admired the weeping-willow with its long branches hanging almost to the ground. But you admire it much more now, because you think how wonderful it is that the sap circulates back and forth in the trailing branches. Follow it as I have told you that it goes, and see how wonderful the circulation of the sap is in this tree. It goes from the roots up through the trunk, and down the trailing branches to the very tips of the leaves ; and then it mounts up again through other pipes in the branches to the trunk, that it may go down again to the roots. CONCLUSION. 119 Flowers and leaves. As you think of all this, do not the beautiful branches, as they swing back and forth in the wind, look more beautiful than ever ? You have always loved to look at flowers with their various colors. But now you love them more than ever, because you know something about how they grow, and what their colors and perfumes are made from, and many other interesting facts about them. Even fruits will, I think, taste better to you, for what you have learned about them in this book. Leaves are such common things that most people do not know how beautiful they are. From what I have tofd you about them, I think you will always be ready to examine them, and see what a variety of beauty there is in the leaves of different trees and plants. And when you think what is done in the leaves, and how the sap comes continually to them to be aired, you admire them more than they do who think of them merely as pretty green tilings. Think of a leaf as made , for growing is making. No one can make leaves but God. But suppose that a man could make leaves and put them on a tree. It would take him his whole life to cover a tree of any size with leaves. But God, as I have told you, makes the leaves out of sap on all the plants and trees. He sends to them the warm breezes of spring, and sets the sap run- ning in the pipes, and then the buds come out, and from them are formed the leaves. What a busy workshop, as you may say, is every plant and tree in the spring when all the leaves are making ! I have told you about the wonderful change that we see in plants and trees year by year. What multitudes of leaves and 120 CONCLUSION. Changes in winter and spring. “ Seed-time and harvest shall not cease.” flowers fall to the ground every year and decay ! What a waste, as it seems, of beautiful things ! But are they really wasted ? Oh no ! God, as I have told you, can make again from these decayed leaves and flowers other leaves and flowers just as beau- tiful as these once were. How wonderful this is ! Look out in summer, and see on trees, and shrubs, and plants, flowers of every color mingled with the green leaves. What a world of varied beauty you behold ! You can not believe that all this will be soon gone. But wait a little and there are no leaves nor flowers. All is bare and dreary. The leaves and flowers have fallen in all their beauty, and the snow covers them as with a winding-sheet. Is it possible that all this beauty that we have seen thus buried can be revived again ? Will the green grass again appear ? Will these bare trees and shrubs again be covered with leaves and blossoms, and will the flowers again spring up ? Oh yes ! We have seen God do all this year after year, with the sunshine, and the rain, and the dew of spring ; and he will do it again, for he has said that “ seed-time and harvest shall not cease.” Questions . — With what thoughts and feelings will what you have learned in this book make you look at plants and trees ? What is said about the weeping-willow ? What about flowers and fruits ? What about leaves ? What is said about leaves being made? What is said of the change that you see every year in plants and trees ? Tell about the change from summer to winter, and then from winter to summer. THE END. THE CHILD’S BOOK OF NATURE, FOR THE USE OF FAMILIES AND SCHOOLS. INTENDED TO AID MOTHERS AND TEACHERS IN TRAINING CHILDREN IN THE OBSERVATION OF NATURE, IN THREE PARTS. PART II. —ANIMALS. By WORTHINGTON HOOKER, M.D., AUTHOR OP “FIRST BOOK IN CHEMISTRY,” “CHEMISTRY,” “NATURAL PHILOSOPHY,” “NATURAL HISTORY,” ETC. tOitl) Illustrations. NEW YORK: HARPER & BROTHERS, PUBLISHERS, FRANKLIN SQUARE. 188 2 . By Dr. WORTHINGTON HOOKER. THE CHILD’S BOOK OF NATURE. For the Use of Families and Schools; intended to aid Mothers and Teachers in training Children in the Observation of Nature. In three Parts. Illustrations. The Three Parts complete in one vol., Small 4to, Cloth, $1 00 ; Separately, Cloth, Part I., 40 cents; Parts II. and III., 44 cents each. Part I. PLANTS.— Part II. ANIMALS.— Part III. AIR, WATER, HEAT, LIGHT, &o. FIRST BOOK IN CHEMISTRY. For the Use of Schools and Families. Revised Edition. Illustrations. Square 4to, Cloth, 44 cents. NATURAL HISTORY. For the Use of Schools and Families. Illustrated by nearly 300 Engravings. 12mo, Cloth, 90 cents. SCIENCE FOR THE SCHOOL AND FAMILY. Part I. NATURAL PHILOSOPHY. Illustrated by nearly 300 Engravings. 12mo, Cloth, 90 cents. Part II. CHEMISTRY. Revised Edition. Illustrations. 12mo, Cloth, 90 cents. Part III. MINERALOGY AND GEOLOGY. Illustrations. 12mo, Cloth, 90 cents. Published by HARPER & BROTHERS, Franklin Square, N. Y. 5J3P* Either of the above volumes will be sent by mail, postage prepaid , to any part of the United States or Canada , on receipt of the price . Entered according to Act of Congress, in the year one thousand eight hundrd and fifty- seven, by Harper & Brothers, in the Clerk’s Office of the District Court of the Southern District Court of New York. PREFACE. Having presented in Part First such facts or phenomena of Vegetable Physiology as would be interesting to a child, I proceed in this Part to do the same with Animal Physiology. The teacher and parent will observe, that in doing this I bring out quite prominently the analogies that exist between the animal and the vegetable world in the operations of life. Such analogies are always interesting to the child as well as to the adult, and the consideration of them adds much to the enjoyment of the observer of nature, for it opens to him the simple plans and principles upon which the Creator works out the almost endlessly varied results that life, both animal and vegetable, presents to our view. What is true of the analogies that exist between the two king- doms of life is also true of those that we find in each kingdom by itself. I have therefore, in this Part, traced the resemblances which the contrivances in the human system bear to those which we see in animals of different kinds, and also the differences, giv- ing to some extent the reasons for them — that is, I have made it in some measure a book of comparative physiology. The effect of this mode of treating the subject will be to interest the child’s IV PEEFACE. mind in the observation of the various animals, great and small, that he sees from day to day. Natural History, which is other- wise rather a dull study, will thus become very attractive to him. And, to further this object, which I deem to be of great import- ance, I have noticed the habits of some animals in such a manner as to connect distinctly Physiology with Natural History, a rela- tion which, though an obvious one, has very generally been dis- regarded. While I have aimed in this Part at the same kind of simplic- ity as in the First, there are some points in it which require a greater compass of mind to understand. This is as it should be ; for in going through the First Part there will, of course, be ac- quired by the learner some amount of skill in observation and rea- soning. I have taken special care, however, not to presume too much upon the mental advance thus made. WOETHINGTON HOOKEE, CONTENTS. CHAPTER PA3-R I. WHAT IS MADE FROM THE BLOOD 7 II. MORE ABOUT WHAT IS MADE FROM THE BLOOD 10 III. HOW THE BLOOD IS MADE 13 IY. MOTHER EARTH 15 V. THE STOMACH AND THE TEETH 19 YI. MORE ABOUT THE TEETH 22 VII. THE CIRCULATION OF THE BLOOD 26 VIII. BREATHING 30 IX. BRAIN AND NERVES 34 X. HOW THE MIND GETS KNOWLEDGE 40 XI. SEEING 47 XII. HOW THE EYE IS GUARDED 52 XIII. HEARING T 57 XIV. THE SMELL, THE TASTE, AND THE TOUCH 63 XV. THE BONES 68 XVI. MORE ABOUT THE BONES 72 XVII. THE MUSCLES 77 XVIII. MORE ABOUT THE MUSCLES 82 XIX. THE BRAIN AND NERVES IN ANIMALS 87 XX. THE VARIETY OF MACHINERY IN ANIMALS 91 XXI. THE HAND 96 XXII. WHAT ANIMALS USE FOR HANDS 102 XXIII. THE TOOLS OF ANIMALS 109 vi CONTENTS. CHAPTER PAGE XXIV. MORE ABOUT THE TOOLS OF ANIMALS 115 XXV. INSTRUMENTS OF DEFENSE AND ATTACK 122 XXVI. WINGS 131 XXVII. COVERINGS OF ANIMALS 138 XXVIII. BEAUTY OF THE COVERINGS OF ANIMALS 142 XXIX. HOW MAN IS SUPERIOR TO ANIMALS 148 XXX. THE THINKING OF ANIMALS 153 XXXI. MORE ABOUT THE THINKING OF ANIMALS 157 XXXII. WHAT SLEEP IS FOR 162 THE CHILD’S BOOK OF NATURE. PART IL— ANIMALS. CHAPTER I. WHAT IS MADE FROM THE BLOOD, The blood the building material of the body. T HAVE told you, in Part First, liow every tiling in a plant or tree is made from the sap. This is, then, the building mate- rial, as we may say, of the plant. Now every thing in your body is made from the blood. The blood, then, is to your body what sap is to a plant. It is the common building material of the body. You remember what I told you in Part First about the full- blown rose. This is made from the sap that comes to the bud through the pipes in the stem. Just so the little finger of the child becomes the large finger of the man, from the blood that comes to it through the pipes in the arm. And as the stem of the plant grows larger all the time, so does the arm of a child. The sap makes the stem grow, and the blood makes the arm grow. If you cut off a branch of a plant it stops growing, because the sap does not come to it any longer. It soon dies and decays. So, if the arm of a child be cut off, it can not grow, because no 8 WHAT IS MADE FROM THE BLOOD. The twig and the infant. Variety of the things made from the blood. more blood can come to it. y Like the cut-off branch, it dies and decays. You see a twig come up out of the ground. It grows larger and larger every year. Soon it is a small tree. After many years it becomes very large, and spreads out its long branches over a great space. As you look up into it, you think of all that you see, its branches and leaves, as having been made from the sap that is continually running in its pipes. Now, as the little twig becomes a tree, so the infant in the cradle becomes the large man. And when you look up at a man, you can think of all his body as having been made from the blood that runs every where in its pipes, just as you think of a tree as made from the sap. It is wonderful, as you have seen in Part First, how many and how different things are sometimes made from the same sap. Look at an apple-tree. There are the hard wood, the rough bark, the tender leaves, the beautiful blossoms, and the pleasant fruit, all made from the same sap. But the variety of things made from your blood is much more wonderful. Look at some of the things that are made from the blood. See the skin, the hair, the nails. Look at the soft red gums and the hard white teeth in the mouth. Then look at the eye. See the eyelids, the eyelashes, the firm, pearly-white coat of the eyeball, and the clear window in the front part of the eye. See, too, in- side of this window, that round, colored curtain, with an opening in the middle that we call the pupil. All these different things that you see are made from the same blood. Then there are many other things inside of the body that WHAT IS MADE FKOM TIIE BLOOD. 9 Bones, muscles, lungs, brain, nerves, bile, tears, etc., made from the blood. you can not see. These are the hard bones, the red muscles, the white, shining cords by which the muscles pull the bones, the light, spongy lungs, the thick and firm liver, the soft brain the white nerves, etc., etc. How strange it is that all these parts of the body, so different from each other, are made from the same building material, the blood. But this is not all. The wax in your ears is made from the blood. So is the bile, that bitter stuff that is manufactured in the liver. The tears, too, are made from the blood. There are many other liquids in the body that are made from this com- mon material. "When you look into a person’s eye you look into a watery fluid, and the back part of the ball of the eye is filled with a sort of jelly; both of these are made from the blood. But even this is not all. The arteries and veins in which the blood runs are made from the blood. Even the heart that pumps the blood is made from the blood that it pumps. This is as strange as it would be to have the walls of a canal made from the water that runs in it, or to have a pump made from the water that it pumps out. Questions . — What is every thing in a plant made from ? What is every thing in your body made from ? Tell what is said about the bud and the finger, and about the stem and the arm. What is said about cutting off a branch and an arm ? How is a child compared to a twig? Mention the different things in an apple-tree that are made from the sap. Are there more things made from your blood? Mention some of them that you can see. Mention some that are inside of the body that you can not see. 'What is said about the ear-wax, the bile, the tears, etc. ? What about the arteries and veins, and the heart ? 10 MORE ABOUT WHAT IS MADE FROM THE BLOOD. How wonderful it is that so many things are made from the blood. CHAPTER IT. MOKE ABOUT WHAT IS MADE FROM THE BLOOD. How different from each other are some of the things that are made from the blood ! You could hardly believe that the white, hard teeth are made from the same blood that the red, soft gums are. Suppose that while you are in a China-ware factory a man should tell you that even the whitest China is made from a red liquid, and that they also make in this factory fine red cloth from this liquid. You would not believe him. But white China-ware and the fine red cloth are not any more unlike than the teeth and the gums. Suppose, now, that he should show you a yellow, bitter fluid, and then a clear, soft eye-water, and tell you that these he makes from the same red liquid from which the China and the red cloth are made. This certainly you would not believe. And yet, in our bodies, the bile and the tears are made from the same blood with the teeth and the gums. But not only are a few things very much unlike made from the blood, but many things that differ from each other, some of them much and some but little. Suppose that the China-ware maker should tell you that besides making white China and red cloth from his red liquid, he made also a variety of both hard and soft things, such as velvet, and various kinds of cloth, nails, glass, etc. Impossible! you would say. But this is no more won- MORE ABOUT WHAT IS MADE FROM THE BLOOD. 11 The China-ware factory. The body the house of the soul. derful than that hair, teeth, gums, nails, bones, and all the different parts of the body should be made from that red fluid — the blood. But suppose, again, that the China-ware man should tell you that his factory was made from the same red fluid from which he manufactures so many things in it — that the very pipes that carry the fluid around the building were made from it, and so also was the pump that sends it through these pipes. This would seem to you strangest of all. And yet all the various machinery of the body is made from the blood. The liver, that manufactures bile from blood, is itself made from blood ; and so of other things ; even the pipes in which the blood runs all over your body, and the heart that pumps it into them, are made, as I have before told you, from the blood. The body is the house or habitation of the soul. It is a well- built and a well-finished house. The bones are its timbers. The skin is its covering. The hair is its thatched roof. The eyes are its windows. It is a house that can be easily moved about, just as the soul wishes. There is for this a great deal of ma- chinery in it. And the soul has little cords, called nerves, run- ning to all parts of this machinery, like telegraphic wires. There are also other kinds of machinery, as the breathing machinery, the machinery for taking care of the food, and the machinery for circulating the blood. The soul resides in the top of this house, the brain. Here it sends out messages every where by the little cords, and receives messages by them. Here it thinks and acts, and some of the time sleeps. This part of the house is very cu- riously and beautifully fitted up. 12 MORE ABOUT WHAT IS MADE FROM THE BLOOD. All the parts and the furniture of the soul’s house made from blood. Now all the various parts of this house are made, as I have told you, from the blood, and yet there is more variety in them than there is in the parts and furniture of the houses that man builds. Suppose that a man should show you a great quantity of a red liquid, and tell you that with that he intended to build a house and furnish it — that he should make from it all his stones, and bricks, and timbers, and glass, and nails, and plaster, and papers for his walls, and paints of different colors, and then his carpets, and mirrors, and chairs, and curtains, etc., etc. You would say that the man is crazy. But God makes from that red fluid, the blood, all the parts of the house of the soul. Exactly in what way all the different parts of the body are made from the blood we do not know. Wise men have studied this a great deal, and they have found out some things about it. What they have found out you are not yet old enough to under- stand. After all, the wisest men know but little about it, and, with all their wisdom, they do not know enough to make skin, or hair, or any thing else that you see in your body from the blood any more than, as I told you in Part First, they can make even a simple leaf from the sap. Questions . — What is said about the teeth and the gums ? Give the comparison about China and cloth. What is said about the tears and the bile ? What is said about the variety of things made from the blood ? Give the comparison about the China-ware factory and the machinery of the body. What is said about the differ- ent parts of the habitation of the soul? In what part of this house does the soul re- side? Give the comparison about a house and its furniture. What is said about wise men ? HOW THE BLOOD IS MADE. 13 Blood made from food. The mouths in the stomach. CHAPTER III. HOW THE BLOOD IS MADE. I have told you what is made from the blood, and now you will want to know how the blood itself is made. The blood in your body is made from the food that you eat. It is made very much in the same way that the sap in the plant is made. This sounds strange to you, but it is true. You re- member that I told you in Part First that the plant’s food is in the ground, and that the root is its stomach. You remember what I told you about the little mouths in the root that suck up the plant’s food out of the ground. There are little mouths in your stomach that suck in the nourishing part of the food that you eat, as the mouths in the root suck up the nourishing part of the earth. And the stomachs of all animals have these little mouths. The mouths in the root of a plant do not, you know, suck up all the soil. They drink in only what is good to make the plant grow. So the mouths in the stomach of an animal do not suck up all the food ; they suck up only that part of the food that will make the animal grow — that is, what will make good blood. There is, you know, no sap in the ground, but there is what can be made into sap. So there is no blood in your food, but there is in it what can be made into blood. It is the business of the mouths in the root to take in what will make sap,, and so it is the business of the mouths in the stomach to take in what will make 14 HOW THE BLOOD IS MADE. Variety of our food. Stomachs of animals suited to their food. blood.' And they generally clo this business very faithfully. It is very seldom that they take in what they ought not to. You have seen how many different things are made from the, blood. This is very wonderful. But it is quite as wonderful that the blood can be made from so many different kinds of food as you sometimes take into your stomach. Just think of all the various things that you sometimes eat at dinner — meat, potato, turnip, squash, apple-sauce, cranberry, celery, pie, filberts, raisins, etc. It seems strange that red blood can be made from such a mixture as this. But so it is. There is something in all these different things that helps to make the blood. The blood is made from different things in different animals. The cow, you know, never eats meat. It would be of no use in its stomach. The mouths there would not suck up any thing from it. This is not their business. Their business is to suck up some- thing from grass, and meal, and potatoes, etc., but not from meat. So grass would be of no use to a dog. The Creator has made the stomach of the cow in such a way that it can get from grass what is needed to make blood; and he has given such a stomach to a dog that blood can be made from the meat that he eats. Our stomachs are made in such a way that our blood can be made from a great many different things ; and so the variety of our food is much greater than that of such animals as the cow and the dog. Questions . — From what is the blood made ? How is an animal’s stomach like the root of a plant ? What part of the food do the mouths in stomachs and in roots suck up ? What is said about the different kinds of food that blood is made from ? Tell about the food of the cow and the dog. What is said about our stomachs ? MOTHER EARTH. 15 Our food in the ground. The plants gather it and fit it for our use. CHAPTER IY. MOTHER EARTH. The food of plants is in the ground, and the roots take it up $ but so, too, is the food of animals in the ground. And yet, if we should fill our stomachs ever so full of earth, we should not be nourished. How is this ? It is because the food is not in the right condition for us while it is in the earth. It must be changed before our stomachs can do any thing with it. Now this is just what the plants do for us. They get this food out of the earth for us, and put it into such a condition that our stomachs can use it. I will make this plain to you. We eat bread made from wheat. It nourishes us — that is, blood is made from it. But what is the wheat? It is grain that is made from the sap that comes up in the pipes of the stalk, and this sap is made from what the root sucks up out of the ground. You see, then, that what the wheat is made from is in the ground ; and all that the plant does is to take this up out of the ground and make it into wheat, so that our stomachs can use it for food. The plant’s stomach, then, we may say, gathers food out of the ground for our stomachs. One of the things that we eat is sugar. Where does it come from? It is made from the earth. But if you should put earth into your stomach, no sugar could be made from it in your body. There are some plants that have to do this for us. They make 16 MOTHER EARTH. Changes in the food while it is becoming fitted for us. sugar from the earth for us to eat. This part of our food then, may be said to be really in the ground, for what it is made from is there. The same thing is true when you eat meat. This meat was once a part of the ground. See how this is. Suppose it is a piece of beef from an ox : the grass that the ox ate was made from sap sucked up from the ground ; then from this grass blood was made in the ox ; from this blood the meat was made ; and now from the meat blood is made to nourish you. See, now, how many changes the food in the ground goes through in this case before it becomes a part of your body. First it becomes sap ; then it becomes a part of the grass ; then in the stomach of the ox it is sucked up, and is changed into blood ; then it becomes a part of the ox ; then it is sucked up in your stomach, and is changed into blood ; and now it is ready to be used in your body to make nerve, or bone, or eye, or tooth, or any part of the house of your soul. You sometimes drink the milk of the cow. This also comes from the ground. See how this is. The cow goes to pasture, and eats the grass that is made from the ground. The cow’s blood is made from this, then milk is made in her bag from the blood, and in you this milk is changed back to blood. So you see that all our food really comes from the earth. There is in the earth under our feet just what makes and nourishes our bodies. We can not get at it ourselves, mixed up as it is with the earth, but the plants suck it up and prepare it for us ; and in this you see the reason for the expression “ Mother Earth.” The MOTHER EARTH. 17 Reasons why animals have a stomach. earth is our mother. We get all our food from the earth as really as the infant gets its food from its mother’s breast. You can also see, from what I have told you in this chapter, the meaning of the text, “Dust thou art, and unto dust slialt thou return.” We are dust, that is, earth ; for we are made from it, and are nourished by what comes from it, and when we die our bodies will become a part of the earth again. You see that there are two reasons why animals have a stomach to put their food in. One is that they want to move about. They could not have a root for a stomach as plants do. They must have a stomach that they can carry about with them. We can sup- pose an animal made like a plant. It might have feet wdth roots sprouted out from them, and these roots might have little mouths which would suck up food as soon as they were put into the ground. But how very awkward and inconvenient this would be ! The animal would be obliged every now and then to bury up its feet with their roots in loose moist earth, and stay still in one spot till enough was sucked up from the earth for its nourishment. And, besides, the roots would be dangling around, and catching in every thing as the animal moved about. Your little feet could not carry you about as nimbly as they now do if you had such roots fastened to them. Another reason is, that the food in the ground is not fitted to nourish an animal. It must be gathered up in plants, and be changed in them, as I have shown you in this chapter, before it can be of any use to animals. The stomach of a plant is much larger than that of an animal. 2 B 18 MOTH Eli EARTH. Why the stomach of a plant is so much larger than the stomach of an animal. The stomach of an animal, you know, is hut a small part of its body ; while the root of the plant — that is, its stomach — is nearly as large as the plant itself. What do you think is the reason of this ? The little mouths in the root of the plant suck up only a small part of the earth, the plant’s food, and so it takes a great deal of earth to give the plant all the sap that it needs. It is for this reason that the root spreads out so far on every side. Now in the animal the mouths in the stomach suck up a great part of the food. It does not require, therefore, a large stomach, for it needs to put but a small amount of food into it. You see, then, that the food of the plant is bulky, as we say, and therefore it must have a large stomach, while the animal can manage its food with a small one. Questions . — Where is the food of animals ? What must be done to it before they can use it ? What do the plants do for us ? Tell about the wheat. What is said about sugar ? What about meat ? Mention the changes that food goes through in this case before it becomes a part of your body. What is said of milk ? What is the reason of the expression Mother Earth ? Explain the text, “ Dust thou art, and unto dust shalt thou return.” What is the first reason given why an animal has a stomach to put his food in ? What is the second reason ? Why is the stomach of a plant so much larger than the stomach of an animal ? THE STOMACH AND THE TEETH. 19 What is done to the food in the stomach. The grinding of the food. CHAPTER Y. THE STOMACH AND THE TEETH. The little mouths in the stomach, as I have told you, suck up from the food what is made into blood, but they do not do this as soon as the food is put into the stomach. The food must be digested first. You have heard people talk about digestion, and now I will explain it to you. When you swallow your food, there is a liquid formed in the stomach that mixes up with it. This liquid, after a little time, changes all the different kinds of food in such a way that the whole looks as if it was all one thing. The meat, and potato, and pie, etc., are not only well mixed, but they are so changed that you could not tell one from the other. When the food becomes changed in this way, the little mouths begin their work upon it. They suck up from it a white fluid very much like milk ; and it is from this fluid that all the blood in our bodies is made. Now observe what is done to the food before it goes into the stomach. There is a mill in your mouth for grinding it up, and a very good mill it is. There are twenty teeth there for the pur- pose of dividing up your food very finely. You can see what the use of this is. The finer the food is, the more easily will the di- gesting fluid in the stomach change it. It takes some time for this fluid to soak through a solid piece of meat or potato. So 20 THE STOMACH AND THE TEETH. Breaking up the food of plants. The saliva factories. you see that you must not swallow your food too fast, but must let the mill in your mouth grind it up thoroughly. Something like this grinding we do sometimes for the food of plants, itou. know that in the spring the gardener digs up his garden, and the farmer plows his fields. What is this for ? It is to loosen up the ground ; that is, it is to break up the food of the plants, so that they can use it well. If this was not done, the hard earth would be to the plants just as your food would be to your stomach if you swallow it without chewing it well. So your teeth do to your food what the spade and the plow do to the food of plants. While the mill is grinding the food, there are some factories about the mouth, making and pouring forth a fluid to moisten it. This fluid, called the saliva, is what you feel in the mouth when the mouth waters, as we say. The two largest of these factories are just below your ears. It is these that swell up so much when one has the mumps. These saliva factories do a moderate busi- ness generally. Most of the time they only make enough liquid to keep the mouth moist. Sometimes they do not make enough even for this. This is the case when your mouth gets dry, as it is apt to do in fever. When you eat, these factories do a brisk business, for they then have to make a good deal of fluid to mix with the food. It seems as if they knew when it was necessary for them to go to work and make more saliva than usual. This, of course, is not so ; but how it is that they are made to work so hard while we are eating we do not know. The food of plants needs moistening just as our food does* THE STOMACH AND THE TEETH. 21 Parched plants and the parched mouth in fever compared. The rain moistens it for the root, the stomach of the plant, so that it may get nourishment from it. When you water the dry earth in a flower-pot, you do for the food of the plant what the saliva factories do for your food. Sometimes in fever, as I have just told you, the mouth is very dry. This is partly because the saliva factories have almost stop- ped work ; hardly any saliva comes through their canals into the mouth. It would be hard work then to eat dry food. The dry cracker must be moistened before it can be eaten. This is very much like what sometimes happens to plants when there has been no rain for a long time. There they are, with their roots in the ground, just as they have been all along. The food is close to their little mouths, but it is so dry that they can not well manage it. They languish, therefore, and perhaps wilt. The dry earth is to them like the dry cracker to the fevered mouth. Questions . — What is done to the food in the stomach ? What do the months in the stomach suck up ? What is done to the food before it goes into the stomach ? What is the use of grinding the food ? What harm does it do to eat fast ? What is said about the food of plants ? What else is done to our food while the teeth are grinding it ? Tell about the working of the saliva factories. What is said about moistening the food of plants ? How are plants sometimes like persons in a fever ? 22 MORE ABOUT THE TEETH. The different kinds of teeth for cutting, and tearing, and grinding. CHAPTER VL MORE ABOUT THE TEETH. Notice that in the mill in your mouth there are different kinds of teeth. They are for different purposes. The front teeth are for cutting the food ; the large back teeth are for grinding it up fine; the pointed teeth, called the stomach and eye teeth, are for tearing the food. You can see these different kinds of teeth in different animals. Every animal has such teeth as it needs to divide its food. The dog and the cat eat meat, and they want to tear this to pieces ; they therefore have long, sharp, tearing teeth ; so, too, have the lion and the tiger, for the same reason. Now look at the cow’s mouth : she has no tearing teeth. The grass that she eats does not need to be torn ; it needs to be bruised and ground up, and for this purpose she has large, broad, grinding teeth. These are her back teeth. But you notice that the cow has a few different teeth in front ; they are made to cut. Now watch a cow as she eats grass, and see how she uses these two kinds of teeth. With the front teeth she bites the grass — that is, she cuts it ; then with the end of her tongue she puts it back where the grinding teeth are, to be ground before it goes into the stomach. So the cow has in her mouth both a cutting machine and a mill. The horse has these two kinds of teeth, as you see represented MORE ABOUT THE TEETH. 23 The teeth of the horse, the cow, and the giraffe. in this figure, which is the skull of a horse. Now when you eat an apple you do very much as the cow or the horse does with the grass ; with your front cutting teeth you bite off a piece ; then it is pushed back where the grinders are, and they grind it up into a soft pulp before you swallow it. The cow does not always use her cutting teeth in the way that I have mentioned. See her as she eats hay ; she does not cut this as she does the grass. With those front cutting teeth she merely takes up the hay, and it is gradually drawn back into the mouth, the grinders all the while keeping at work on it. If the hay is in a rack, she pulls it out with her cutting teeth. It is the same with the horse. That beautiful and singular animal, the gi- raffe, which you see here, has these two kinds of teeth. This ani- 24 MORE ABOUT THE TEETH. Tearing teeth. Stomachs of the cow. mal, when of full size, is three times the height of a tall man ; it lives on the leaves of trees, which it crops with its front teeth, grinding them up with its large back teeth, as the cow and horse do their hay and grass. You notice that your tearing teeth are not nearly as long and powerful as these teeth are in dogs, cats, tigers, etc. What is the reason of this ? It is because, although you eat meat as they do, you can, with your knife and fork, cut up your food. They do not know enough to use such things, and so God has given them long, sharp teeth to tear their food to pieces. The cow grinds the grass and hay twice. So do the sheep, the deer, the camel, the giraffe, and many other animals. See the cow cropping grass in the pasture ; she grinds it partly in her mouth as she crops it, and then stows it away in a very large stomach that she has for the purpose ; after a while she stops eating, and you see her standing or lying in the cool shade chewing her cud, as we say. That large stomach is very full of grass now, and this is all to be chewed over again. How do you think this is done? I will tell you. After the grass is well soaked in this large stomach, it passes into another, for the cow has more than one stomach — she has four. In this second stomach the grass is all rolled into balls. This is a very curious operation. Now each one of these balls goes up into the mouth to be chewed over again. After it is well chewed, down it goes again, but it goes into still another stomach, and then up comes another ball to take its place ; and so the cow goes on till all the balls are chewed. If you look at the MORE ABOUT TIIE TEETH. 25 Chewing the cud Gizzards of birds. cow’s neck while she is doing this, you can see when the ball goes up and when it goes down. She seems to have the same quiet enjoyment while thus chewing her cud that the cat has when, with her eyes half open, she lies purring and wagging her tail after a full meal. Birds, you know, have no teeth. Their mill for grinding food is not in the mouth, it is in the stomach. What we call the giz- zard is this mill. See a hen pick up the corn that you throw to her. She swallows it very fast. Where do you think it goes to ? It goes into a bag called the crop. Here it is soaked, just as the grass is in the large stomach of the cow. When it becomes soft enough it goes into the gizzard. Here it is crushed so as to make a soft pulp by being rubbed between two hard surfaces, as corn in a mill is ground between two mill-stones. If you cut open the gizzard of a fowl, you can see how well these surfaces are fitted to grind up the corn. They do it quite as well as teeth would. Birds that live on food that does not need grinding do not have a gizzard, but a common stomach. Questions . — What are the different kinds of teeth that you have in your mouth, and what are they for ? What is said about the teeth of the dog, cat, etc. ? What is said about the cow’s back teeth ? What of her front ones ? Tell how the cow uses these two kinds of teeth in eating grass, and how in eating hay. How do you eat an apple? Tell about the giraffe. Tell about the cow’s chewing her cud. What is the crop of a bird for ? What is the gizzard for ? Do all birds have giz- zards ? 26 THE CIRCULATION OF THE BLOOD. Arteries and veins. The heart. The capillaries. CHAPTER VII. THE CIRCULATION OF THE BLOOD. You remember that I told you in Part First how the sap cir- culates in a plant or a tree. It goes up in one set of pipes, and goes down in another set. Just so it is with the blood in your body ; it is always in motion. There are two different sets of pipes for it to go back and forth, as there are in the plant for the sap ; these two sets of pipes are called arteries and veins. The blood in your body is kept in motion by a pump that works all the time, night and day. This pump is in your chest. It is the heart. Put your ear to the chest of some one, and you can hear its working as it pumps out the blood. You can hear it in your own chest sometimes when it works very hard. When you have been running very fast you can hear it. The heart pumps the blood out at every beat into a large artery. From this great main pipe other pipes or arteries branch out every where, and from these branches other branches go out ; dividing in this way, like the branches of a tree, the arteries at last are very small. At the ends of the arteries there are exceedingly small vessels. They are called capillaries, from the Latin word cajpilla , which means a hair. They are really smaller than the finest hairs, for you can not see them. When you cut your finger you divide a great many of these vessels, and the blood oozes out from them. THE CIRCULATION OF THE BLOOD. 27 How arteries are guarded more than veins, and why. When any one blushes, these capillaries in the skin of the face are very full of blood, and this causes the redness. It is the blood in these little vessels that makes the lips red. These capillaries are every where, so that wherever you prick with a pin the blood will ooze out. The blood goes out from the heart by one set of pipes, and comes back to the heart by another set. It goes out from the heart by the arteries, as I have just told you ; it comes back to the heart by the veins. The veins lie, some of them, very deep, and some just under the skin. You see some of them under the skin in your arm and hand. But you can, not see the arteries ; they nearly all lie deep. Think of the reason of this. If an artery of any size is wounded, it is not easy to stop its bleeding, for the heart is pumping blood right through it ; but it is easy to stop the bleeding of a wounded vein, because the blood is going in it quietly back to the heart. Now it is because it is so dangerous to wound arteries that God has placed them so deep that they can not easily be wounded. The maker of our bodies has guarded the arteries in another way. He has made them much stronger than the veins. If they were not made very strong they would now and then burst. You sometimes see the hose of a fire-engine burst when they are work- ing the engine very hard ; but, though your heart pumps away sometimes so fast and hard, as when you have been running, not one of all the arteries gives way ; but they would often burst if they were not made stronger than the veins are. The blood in the arteries is red ; but the blood that comes back 28 THE CIRCULATION OF THE BLOOD. Circulation of the sap. Pumping of the heart. to the heart in the veins is dark. This is the reason that the veins which you see under the skin look dark. I will tell you more about the dark and the red blood in the next chapter. You see that the blood is kept in motion in a different way from what the sap is. In a large tree there is a great deal of sap going up in its trunk all the time, but there are no large pipes there like our arteries and veins. The sap goes up and down in a mul- titude of very small pipes, and there is no pump in the tree, as there is in our bodies, and in the bodies of other animals. How the sap goes up to the top of the tallest tree without being pump- ed up we do not know. The heart is at work, as I have told you, all the time, while you are asleep as well as when you are awake. If it should stop pumping the blood, you would die. How steadily it works, going tick-tack all the while ! How much work it does in a lifetime ! It takes but a few days for it to beat a million of times ; and here I will give you something about this work of the heart that I wrote in another book.* If the heart could think, and know, and speak, suppose it should count up how marry times it has to beat before the days of seven- ty years are numbered and finished. I think it would feel a little discouraged at the great, long work that was before it, just as some people do when they look forward and think how much they have to do ; but remember that the heart has a moment in which it can make every beat. There is time enough to do the work; it is not expected to make two or more beats at once, but only one. * Every-day Wonders ; or, Facts in Physiology. American Sunday-school Union. THE CIRCULATION OF THE BLOOD. 29 Cheerful working. The discontented pendulum. As the heart can not think, it does not faint with discourage- ment, but goes right on with its work, doing in each moment the duty of that moment ; and it would be well if people that can think, whether children or adults, would take a lesson from this little busy worker in their bosoms. If one goes right on, perform- ing cheerfully every duty as it comes along, he will do a great deal in a lifetime, and he will do it easily and pleasantly, if he does not keep looking ahead and thinking how much he has to do. There is a pretty story, by Miss Jane Taylor, about a discon- tented pendulum. The pendulum of a clock in a farmer’s kitch- en, in thinking over the ticking that it had got to do, became dis- couraged, and concluded to stop. The hands on the clock-face did not like this, and had a talk with the pendulum about it. The pendulum was, after a while, persuaded to begin its work again, because it saw, as the hands said, that it always had a moment to do every tick in. The pendulum’s foolish waste of time in complaining made the farmer’s clock an hour too slow in the morning. Questions . — What is said about the circulation of the sap and the blood ? What is said about the heart ? What about the arteries ? What are the capillaries ? By what pipes does the blood come back to the heart ? Where can you see some of the veins? Why are the arteries laid deeper than these veins? Why are they made stronger than veins ? What is the color of the blood in the arteries ? What is its col^or in the veins ? Is the sap kept in motion in the same way that the blood is ? What is said about the work that the heart does ? Tell about the pendulum. 30 BREATHING. The blood changed from dark to red in the lungs. CHAPTER VIII. BREATHING. What do you breathe for? That is plain enough, you will say : I can not live without breathing. But why is it that your life depends on your breathing ? This I will explain to you. You remember that I told you that the blood that comes back to the heart in the veins is dark ; it is not good blood. It has been used while it was in the capillaries in building and repairing bone, and skin, and muscle, and nerve, etc. It is not fit to be used again so long as it is dark blood. What shall be done with it ? It must be made in some way into good red blood again. Now the factory where this is done is the lungs. Just as fast as the dark blood comes to the heart, it sends it to the lungs to be made into red blood, then it goes back to the heart to be sent all over the body. But how, you will ask, is the dark blood changed into good red blood in the lungs ? It is done by the air that you breathe in ; every time that you draw a breath, air goes down into the lungs and changes the blood that it finds there. And now you see why it is that you have to breathe to keep alive. If the air does not go down into the lungs, the dark blood that is there is not changed into red blood : it goes back to the heart dark blood, and is sent all over the body ; but this dark blood can not keep you alive : it is the red blood that does this. BREATHING. 31 Drowning. Situation of the heart and lungs of fishes. Gills of fishes. You see, then, how death is caused in drowning ; the air is shut out by the water, and the blood is not changed in the lungs ; so the blood goes back to the heart dark instead of red, and is sent all over the body. The heart and the lungs fill up your chest. The lungs cover up the heart, except a little part of it on the left side : this is where you can feel its beating so plainly. Here is a figure of the heart and lungs ; the lungs are drawn apart, so that you can see the heart, and its large arteries and veins. You see, marked a, the windpipe by which the air goes down into the lungs. The lungs are light, spongy bodies. They are light because they are full of little cells for the air to go into. It is in these cells that the blood is changed by the air. And now I will tell you about the lungs of fishes. But perhaps you will say that fishes do not breathe, and it can not be that they have lungs, for they would be of no use to them. It is true that they do. not have such lungs as we have; but they have lungs, and they really do breathe air. How is this, you will ask, when they live in the water ? There is a good deal of air always mixed up with water, and the lungs of a fish are so made that the air in the water can change the blood in them. The gills of a fish are its 32 BREATHING. IIow fishes breathe. Breathing of the lamprey eel. The voice. lungs, and the way that they are used is this. The fish takes water into its mouth, and lets it run out through the gills, and so the air that is mixed with the water changes the blood in them. Our lungs are fitted to breathe air alone, but the fish may be said to breathe air and water together. Air alone does the fish no good ; he can not live in it ; he must have his air mixed with water, or it is of no use to him. Here is a picture of the lamprey eel. You see that it has a row of holes on its neck: these are open- ings that lead to its lungs ; there are seven on each side. It is from this that it is sometimes called sev- en-eyes. Insects have such openings into their lungs. The grasshopper has twenty-four of them, in four rows. So you see that there are different ways of breathing in different animals. They do not all breathe through their mouths and noses, as we do. You see that the chief use of breathing is to air the blood; but it is of use to us in another way. It makes the voice. We could not speak if we did not breathe. The sound of the voice is made in the top of the neck, in what we call Adam’s apple. This is a sort of musical box at the top of the windpipe : in this box there are two flat cords stretching right across it. Now when we speak or sing, the sound is made in this way : the air, coming up out ot BREATHING. 33 The voices of animals. The purring of the cat. The croaking of the frog. the lungs, strikes on these cords, and makes them shake or vibrate. It is just as the vibration of the fiddle-string makes a sound when the bow is drawn over it. If you look at an JEolian harp fixed in a window, you can see that the strings are made to quiver by the wind, and this causes the sound. In the same way, the wind that is blown up from your lungs makes the cords in the Adam’s apple vibrate ; and the chest may be said to be the bellows of that little musical box or organ that you have in the throat. Many animals have a musical box in the throat similar to ours. The lowing of the cow, the barking of the dog, and the mewing and squalling of the cat are all done in such a box. You perhaps have wondered how the cat purrs. This noise is made in the same box where she does her mewing and squalling ; for if you put your finger on her Adam’s apple while she is so quietly purr- ing, you can feel a quivering motion there. Fishes, you know, have no voice. They have no musical box. If they had they could not use it, for the only way in which it can be used is to blow air through it. The frog can not use his so long as he is under water ; he has to stick his head up out of water when he wants to croak. Questions . — What do you breathe for ? How is the blood in the lungs changed ? What would it do if it were not changed? How is death caused in drowning? How are the heart and lungs situated ? Why are the lungs so light ? What is said about the lungs of fishes ? What is said about the breathing of the lamprey eel ? What about the breathing of the grasshopper ? How is the breathing of use besides changing the blood? Tell how the voice is made. What is said about the voices of animals ? Where is the cat’s purring done ? Why do fishes have no musical box ? What is said about the croaking of frogs ? 2 C 34 BRAIN AND NERVES. The body the soul’s house, with a great deal of machinery in it. CHAPTER IX. . BRAIN AND NERVES. I HAVE told you .some things in the previous chapters about how the body is built and kept in repair. I have told you that the blood is the building material from which all the parts of the body are made. The use of food, you have seen, is to make the blood, and the chief use of the breathing is to keep the blood in good order. The heart, with its arteries and veins, keeps the blood moving all about the body, so that it may be used in build- ing and repairing. But what is the body built and kept in repair for ? It is a house for the mind or soul. The soul — the thinking part of you — so long as it remains in this world, dwells in the body. The body is something more than a house for the soul. The head, where the soul dwells, is but a small part of the body. But it uses all parts of it. When the hand is moved, the soul uses the hand ; when you walk, it uses the legs and the feet ; when you see, it uses the eyes ; it uses the ears as its instruments to hear with, and the nose is its smelling instrument ; and so of other parts. You can think, then, of the body as having in it many different kinds of machinery that the mind or soul uses. And the object of eating, and drinking, and breathing, and having the blood cir- culate, is to make all this machinery for the mind to use. BRAIN AND NERVES. 35 How the mind uses its machinery. Nerves like telegraphic wires. Let us see, now, how it is that the mind uses the machinery of the body. Raise your hand. What makes it go up ? It is what we call the muscles. They pull upon it and raise it. But what makes them do it ? They do it because you think to have them do it. It is' your thinking mind, then, that makes them raise the arm. But the mind is not there among the muscles ; it is in your head. Now how does the mind get at the muscles to make them work? It does not go out of the brain to them, just as a man goes out of his house among his workmen to tell them what to do. The mind stays in the brain all the time ; but there are white cords, called nerves, that go from the brain to all parts of the body, and the mind sends messages by these to the muscles, and they do what the mind tells them to do. These nerves act like the wires of a telegraph. The brain is the mind’s office, as we may call it ; here the mind is, and it sends out messages by the nerves as messages are sent from a tele- graphic office by its wires. This is done by electricity in the telegraphic office, but how the mind does it we do not know. When you move your arm, something goes from the brain along the nerves to the muscles, and makes them act, but what that something is we do not know. If the wires that go out from a telegraphic office are broken off in any way, the man in the office may send out messages, but they will not go to the place he wishes. He may work his machine, and send the electricity along the wire, but it will stop where the break is. Just so, if the nerves that go to the muscles of your 36 BRAIN AND NERVES. The two sets of nerves. The brain. arm were cut, the muscles could not receive any message from the mind. You might think very hard about raising the arm,dbut the message that your mind sends to the muscles is stopped wdiere the nerves are cut, just as the electricity stops where the break is in the wire. While the mind sends out messages by one set of nerves, it re- ceives messages by another set ; it receives them from the senses. Just see how this is. If you put your finger upon any thing, how does the mind in your brain know how it feels ? How does it know whether it is hard or soft, rough or smooth ? The mind does not go from the head down into the finger to find out this ; it knows it by the. nervous cords that stretch from the brain to the finger. When you touch any thing, something goes, as quick as a flash, from the finger along these nerves to the brain where the mind lives, and lets it know what kind of a thing it is that your finger has touched. So, when you smell any thing, it is the nerves which connect your nose with the brain that tell the mind what kind of a smell it is. And when you taste any thing, it is the nerves of the mouth that tell the mind in the brain whether it is bitter, or sweet, or sour, etc. So, too, when you see any thing, it is the nerve which connects the eye with the brain that tells the mind what it is that you see. The brain, in which the mind lives and with which it thinks, is the softest part of the body. You can see what sort of a thing your own brain is by looking at the brain of some animal at the meat-market. You can see it very well in the calf’s head when it is prepared for cooking by being sawed in two. I have com- BRAIN AND NERVES. 37 The nerves of the face and head. pared the nerves to the wires that stretch out from the telegraphic office ; but there are only a few wires, while the nerves that branch out from the brain, all over your body, can not be counted. Here is a figure showing how the nerves branch out over the face and head; there are a great many of them, and so there are in all other parts of the body. The nerves, by dividing, spread out, so that there are little nerves every where. If you prick yourself with a pin any where, 38 BRAIN AND NERVES. The mind very busy in attending to all its nerves. there is a little nerve there that connects that spot with the train, and that tells the mind about it. Now all the nerves in all parts bf the body have their beginnings in the brain. In this soft organ are bundled together, as we may say, all the ends of the nerves, so that the mind can use them. There the mind is at its post, just like the man in the telegraph office ; and from that great bundle of the ends of nerves it is constantly learning what is going on at the other ends of them in all parts of the body. A great business the mind has to do in attending to all these ends of nerves in the brain ; and how strange it is that it does not get confused, when so many messages are coming to it over its wires from every quarter! It always knows where a message comes from. It never mistakes a message from a finger for one from a toe, nor even a message from one finger for one from another. And so, too, in sending out messages to the muscles, there is no confusion. When you want to move a finger, your mind sends messages by the nerves to the muscles that do it. The message always goes to the right muscles. It does not go sometimes to the muscles of another finger by mistake, but you always move the finger which you wish to move. And so of all other parts. Messages go from your busy mind in the brain to any part that you move. You can see how wonderful this is, if you watch any one that is dancing or playing on an instrument, and think how the messages are all the time going by the nerves so quickly from the brain to the different parts of the body. I shall tell you more about this in another chapter. The man in the telegraph office receives messages by the same BRAIN AND NERVES. 39 Messages go from the brain by some nerves, and come to it by others. wires by which he sends them out. It is not so, as I have told you before, with the mind’s wires, the nerves ; the mind receives messages from the senses by one set of nerves, and sends messages to the muscles by another set. If you burn your finger, you pull it away from the fire. Now in this case the mind gets a message from the finger by the nerves, and so knows of the hurt. The mes- sage goes from the finger along some nerves to their ends in that bundle of them in the brain ; and the mind, being there on the watch, receives it. Now what does the mind do ? Does it leave the finger to burn ? No ; it sends a message at once along some other nerves to the muscles that can pull the finger out of harm’s way. Questions. — What are some of the things that I have told you in the chapters be- fore this ? What is the body built and kept in repair for ? In what part of the body does the soul live ? Tell how it uses different parts of the body. When your arm is raised, how is it done ? In what way does the mind make the muscles act ? What are the nerves ? How are they like telegraph wires ? What is it that goes along the wires ? Do we know what it is that goes along the nerves ? Give the comparison between cut nerves and broken wires. From what does the mind re- ceive messages ? Tell about touching, smelling, tasting, and seeing. What is said about the brain? What is said about the number of nerves? What is said about the mind’s attending to all its nerves ? What is said about its making no mistakes in its messages ? Give what is said about the burning of a finger. 40 IIOW THE MIND GETS KNOWLEDGE. Knowledge enters the mind by the senses. CHAPTER X. HOW THE MIND GETS KNOWLEDGE. The mind, as you learned in the last chapter, has a sort of tel- egraphic communication with all parts of the body by means of the nerves, and it is all the time receiving messages from the fin- gers, the eyes, the nose, the ears, the mouth, and other parts. These are instruments which the mind uses to get a knowledge of what is around us. It gets different kinds of knowledge by the different instruments. For example, it learns whether a thing is hard or soft by the touch of the fingers, and it learns how it smells by the nose, how it tastes by the mouth, and how it looks by the eyes. There is knowledge, then, going all the time to the mind by the nerves from these instruments. It can not get there in any other way. Suppose the mind was locked up in the brain, and had no nerves going out from it. It could not learn any thing about what is around it ; there might be eyes, and fingers, and ears, and a nose, and a mouth, but these would be of no use to the mind if there were no nerves. See how the child learns about the world of things all around him. When he is first born he does not know any thing. He does not know how any thing feels, or looks, or tastes, or smells. But with his little nerves his mind gets messages from the senses, and so he learns every day about the things that are around him. HOW TIIE MIND GETS KNOWLEDGE. 41 IIow the mind learns about things. The deaf and the blind. Eyes, ears, nose, mouth, and fingers are all the time telling his mind something through the nerves. They tell him first about those things that are in the room where he is, and then, after a while, when he is carried out, they tell him about things that are out of doors, and thus he knows more and more every day. And then, too, the mind thinks about what the senses tell it. It lays up what comes to it by the nerves, and looks it over, as we may say, and in this way it learns a great deal. There is great difference in people in this thinking about what the mind knows by the senses. Some that see and hear a great many things do not know as much as some that see and hear few things. It is because they do not think much about what the senses tell the mind. You see, then, that all that we learn in this world really comes into the mind by the way of the nerves from the senses — the sight, the hearing, the touch, the smell, and the taste. The senses are the inlets or openings by which knowledge enters, and the nerves are the passages by which it gets to the mind in the brain ; and after it gets there the mind thinks about it and uses it in various ways. Some persons, you know, do not have all these inlets for knowl- edge open. For example, some are deaf; in them no knowledge can get into the mind by the ears. Some are blind, and no knowl- edge can get into their minds by the eyes. More knowledge comes into the mind by the sight than by the hearing ; it is there- fore a greater misfortune to be blind than it is to be deaf. It is astonishing to see how much the deaf and the blind can 42 HOW THE MIND GETS KNOWLEDGE. Deaf and dumb. How the blind read. Story of Laura Bridgman. learn if they try. If the mind is wide awake and ready to learn, it can get a great deal of knowledge even when one of the open- ings for it is shut up. It can use the knowledge gained by the other senses in such a way as to make up very much for the loss. A lazy mind, with all the senses letting in knowledge, will not know as much as a busy mind will with one of the senses shut up. In the deaf and dumb the eyes have to answer for both eyes and ears in getting knowledge. They have to do double duty; and they do it very well if the mind is only wide awake and at- tentive to all that it can learn by the eyes. In the blind the ears have to do a great deal more than in those that can see. The fingers also of the blind are very busy, for they learn very much about what is around them by the sense of feeling. There are books now made for their use with raised letters. By passing their fingers over them, they read just as you do by looking at printed letters. And now I will tell you about a girl that has had to get all her knowledge with only one of the senses, the sense of feeling. Her name is Laura Bridgman. When she was in her second year she became very sick. Her sickness lasted a very long time. After she got well it was found that she was blind and deaf, and that she had no taste nor smell ; only one of the five inlets for knowledge was open. All that could come into her mind was what could be learned by the touch alone. But she had an act- ive mind, and so she went round feeling of every thing, to find out all she could about things. The only way that she could know people was by feeling them. HOW THE MIND GETS KNOWLEDGE. 43 Laura in the asylum. Her mother was very kind to her, and the little helpless girl liked to be with her all the time. She followed her about the house, and tried to do things just as her mother did them. She would feel of her mother’s arms and hands while she was doing things, that she might find out how she did them. In this way she learned to knit, which was a great comfort to her, for she did not like to be idle. A kind physician, who had charge of an asylum for the blind in Boston, heard about Laura. He was much interested for the helpless child, and went to see her. He persuaded her mother to let her come to the asylum. Laura did not feel at home at first, but, as they were all kind to her in the asylum, she soon liked it Very much. She now began to learn many things, and I will tell you a lit- tle how the teacher managed with her. He put into her hands different things — spoons, keys, books, etc. Each article had a label on it. The letters on the labels were raised letters, such as are used in teaching the blind. She would feel them all over with the tips of her little fingers, her busy mind all the time thinking about how they felt. Then the labels and the things were put before her, but separated from each other. After a little trying, fehe learned to put the labels on the things right. All this time she did not know that these labels had the names of the articles on them. If she were blind only, she would have known this at once, for she could have been told of it ; but after a while she in some way got this idea into her mind. She was de- lighted, for she had now found a new way of learning things, and of telling about things to others. 44 HOW THE MIND GETS KNOWLEDGE. How Laura learned to read and to converse. And now Laura went on fast with her learning. The letters were separated, and she would put them together so as to spell spoon, key, etc. This was a great amusement to her. Sometimes, when she carelessly placed the letters wrong, she would playfully strike her right hand with her left one, and then, when the letters were placed right, she would pat her head, as the teacher was apt to do when he was pleased with any thing that she had done. After a while the teacher taught Laura to use her fingers in talking, as you, perhaps, have seen the deaf and dumb do. She soon learned to make all the letters in this finger-alphabet, which you can see on page 98 ; and now she could talk with people quite easily, if they happened to know this alphabet. When she had any thing to say, she would make the letters with the fingers, while the person to whom she was talking would look at her. But how do you think that she managed when this person said any thing to her with his fingers ? She could not see his fingers, but she could feel them, and this was the way in which she knew what was said to her ; she would carefully, but rapidly, pass her fingers over his as fast as he made the letters. It was surprising to see how quickly the touch of her nimble fingers would tell her mind what letter was made, and how fast she could converse with persons in this way. Laura learned much more at the asylum than we should sup- pose she could with only her one sense of touch. Some persons with the whole five senses do not know as much as she does. She even learned to write ; and writing and knitting were very pleasant employments to her. By writing she could put the HOW THE MIND GETS KNOWLEDGE. 45 Laura’s industry. Her fun. A visit from her mother. thoughts of her busy mind on paper, so that others might read them ; and while she was sitting alone thinking, she liked to make her nimble fingers useful in knitting. It was a great satisfaction to her that, though she had but one sense, she could do some- thing useful. What a pity it is that many children, and many adults too, do not have more of this feeling than they seem to have ! The example of Laura teaches a good lesson to all idlers. Though Laura could never see beautiful things, nor hear pleas- ant sounds, as you do all the time, she was very cheerful, and sometimes she was very funny. She liked to play with her doll ; and as the blind children in the asylum had ribbons tied over their sightless eyes, she tied one over her doll’s eyes. One day she was in her play taking care of her doll as one would of a sick child. She made believe give it medicine, and put a hot bottle to its feet ; and when some one proposed to her to put a blister on its back, she was so much amused that she laughed and clap- ped her hands. After Laura had been some time at the asylum her mother came to see her. She did not know her mother at first, but thought that she was some stranger. She held back and would not come near. Her mother handed her a string of beads which she used to wear when at home. She took them, and as soon as she felt them she knew what beads they were. She put them on her neck, and, showing great joy, said with her finger-language that she knew these came from home. Something else from home was given her. She now drew near, and her mother kissed her. The moment that her mother’s lips touched her she knew who it 46 HOW THE MIND GETS KNOWLEDGE. How Laura knew her mother. was, for that kiss was just like the many kisses her loving mother used to give her. She remembered how those lips used to feel, and they had the same feeling now ; and now she clung to her mother, and put her head into her bosom. They were both very happy. When her mother left her Laura felt sad indeed. She wanted to go with her, but she knew that it was best for her to stay in the asylum, where she could learn so much. Questions . — What are the instruments by which the mind gets its knowledge? How does the knowledge get to the mind ? What good would the instruments do if there were no nerves ? Tell how the child, when first born, learns about things around him. What is said about thinking of what is learned by the senses ? Why may the senses be called the inlets of knowledge ? Tell about the deaf and the blind. Why is it worse to be blind than it is to be deaf? What is said about the amount of knowledge that the blind and the deaf can obtain? What is said about the sense of sight in the deaf and dumb ? What senses do the blind chiefly use in getting knowledge? How do they read? How many of the senses did Laura Bridgman lose ? How did she learn about things before she went to the asylum ? Tell how she learned after she went there. How did she talk with people? Tell about her industry. What is said of her cheerfulness ? What of her fun ? Tell About her mother’s visit. SEEING. 47 The eye a beautiful instrument. Its window and dark chamber. CHAPTER XI. SEEING. The senses by which the mind obtains most of its knowledge are the sight and the hearing. In this chapter we will look at the organ or instrument of sight. The eye is a very beautiful instrument. It is very nicely made, and it has a great many different parts. You are not old enough yet to understand all about these parts, but there are some things about them that I can explain to you. What we call the white of the eye is a strong, firm sort of bag. It is filled mostly with a jelly-like substance. It is this that makes it a firm ball. If it were empty it would be like a bag. Into the open part of this, in front, is fitted a clear window. The light goes in here. It can not get in at the sides of the eyeball, through the thick white of the eye. Through this very clear window you can look into the bag or ball of the eye. You can not look through the jelly-like substance that is there, and see the very back of the inside of the eyeball ; but it is like looking into a dark chamber. The reason that it is so dark is, that it is lined with something almost black. If this were not so, the eyes would be dazzled with the light that com- monly goes into them, just as they now are when the light is very bright indeed. Inside of the front window of the eye that I have told you about 48 SEEING. The iris the curtain in the eye. The pupil a round opening in it. there is a fluid as clear as water. In this fluid you see a sort of curtain with a round opening in it. This opening is called the pupil of the eye. It is not always of the same size. When there is a very bright light, it is small ; but when the light is dim, it is large, for then you want all the light that you can get in that dark chamber where the jelly is. You can see the pupil change in its size if you look into the eye of any one while you bring a light very near, and then move it off* quickly. The curtain in which this opening is we call the iris. It is cir- cular. Its outer edge is fastened all round to the inside of the eye- ball. The watery fluid, that I told you is inside of the window of the eye, is on both sides of this curtain. It would not do to have the jelly here, for the curtain would not move easily in that in changing the size of its opening. The iris is, you know, of different colors in different persons. When it is blue, we say that the person has a blue eye ; and if it is quite dark, we say that he has a black eye ; and so of other colors. This curtain makes the eye very beautiful ; but its chief use is, as you see, to regulate the quantity of light that goes into the eye. When there is a great deal of light, the curtain is drawn in such a way as to have the round opening very small ; but when there is little light, it is drawn so as to make this opening large. This curtain must be made very nicely, or it would be puckered when the opening in it is changed in this way. No man could make a curtain of this shape, and have it work like this : it would be a very awkward thing if he should undertake it. He could not possibly make it so that the round opening in it could be made SEEING. 49 The pupil in the eye of the cat and the horse. smaller and larger without wrinkling. But look at this beautiful curtain in the eye, and see how smooth it is, and how perfectly round its edge keeps, as the size of the pupil is changed. Did you ever see any thing work more prettily and easily than this, does ? The opening in the curtain is different in different animals. In the cat it is of this shape in the horse it is shaped in this way You can see the difference in the size of the cat’s pupil in different lights : if you look at her eyes in a bright sunlight, and then again in the evening, you will see that it is very much larger in the evening than it is in the day. When the sun is very bright, her pupil is a mere chink, like this but in the evening it is very wide open, shaped in this way But I have not yet told you how you see. It is done in this way. The light that goes in through the pupil makes an image' or picture there of every thing that is before the eye. It makes the image on a very thin sheet spread* out on the back part of the ^ D 50 SEEING. The images in the eye’s dark chamber. Why we have two eyes. dark chamber where the jelly is ; it is just as light makes images of things in a looking-glass, or in the smooth, still water ; the only difference is, that the image or picture in the eye is very small. When you see a tree pictured in the still water, the picture is as large as the tree itself ; but the picture that the light makes of the tree in that dark chamber of your eye is very small. The picture in your eye of a whole landscape, with all its trees, houses, hills, etc., does not cover over a space larger than a ten cent piece. But how does the mind in the brain know any thing about these pictures ? It knows about them by means of a nerve, that goes from the brain to the eye, and is spread out where the pictures or images are made. It would do no good to have the pictures made in the eye, if the nerve could not tell the mind about them. The eye might be perfect, and yet there might not be any seeing. It is as necessary to have the nerve in good order as it is the eye it- self. It is not your eye that sees ; it is your mind, and in seeing it uses both the nerve and the eye. You have two eyes. When you look at one thing, say a house, there is a picture of the house in both eyes. The two nerves tell the mind in the brain about the two pictures. How is this ? Why does not the mind see two houses ? It is because the pic- tures in the two eyes are exactly alike, and both nerves, therefore, tell exactly the same story ; if they did not, then the mind would see two houses ; that is, it would see double, as it is called. You can see double by pressing one eye sidewise while you let the other go free. The eyes of insects are very curious. You remember what 1 SEEING. 51 The eyes of insects. told you about compound flowers. Now, as in a compound flow- er there are a great many flowers together, so it is with the eyes of insects. The eye of a common fly is made up of thousands of eyes ; so, when he looks at any thing, there are thousands of very little images of it made by the light in these eyes, and the nerves tell the fly’s mind, in his little brain, about them. These eyes are so exceedingly small that you can not see them without a micro- scope. How fine, then, must be the nerves that go from them to the fly’s brain ! Your eye is a very wonderful instrument, but God has put thousands of them just as wonderful into the head of the fly that buzzes about you. It is as easy for him to make little eyes as large ones, and he can make a multitude as easily as one. Questions. — By what senses does the mind learn the most ? What is the white of the eye ? What is it filled with ? What is there in the front part of the eye ? What is said about the dark chamber of the eyeball ? What is just inside of the front window of the eye ? What is the pupil of the eye ? What is the iris ? How is it arranged ? What is said of its color ? What is its chief use ? Tell about this. What is said about its being made nicely ? What is said about the shape of its opening in different animals ? What is said about the cat’s pupil in different lights ? Tell about the images made in the eye. What is said about the nerve of the eye ? How is it that, with two eyes, you do not see double ? Why do you have two eyes ? What is said about the eyes of insects ? 52 HOW THE EYE IS GUARDED. The eye seldom hurt. How it is guarded with the bones around it. CHAPTER XII. HOW THE EYE IS GUARDED. The eye, yon know, is a very tender organ. It is therefore guarded thoroughly, and it is really very seldom hurt. But no- tice that it is just where it would be likely to be hurt if it were not thus guarded. It is right in the front part of the head. It must be there for the mind to use it in seeing. And it is much of the time open. You would suppose, then, that it must very often be struck and hit by things that are thrown about ; but it is really very seldom hit so as to be hurt much. The parts about the eye are often injured, but the eye itself generally escapes. We often see the eyelids and the cheek black and blue from a blow, and yet the tender and delicate eye is as sound as ever. People say, in such cases, that the eye is black and blue, but this is not so ; the injury is all on the outside, and does not go into the eye. Now let us see in what ways the eye is guarded. It is in a deep bony socket. There is bone all around it except in front. Then, too, see how the bones stand out all around it. The bone of the forehead juts over it. Below and to the outside stands out the cheek bone, and the nose is its wall on the inside. Now you can see that a blow with a stick would be very likely to strike upon some of these walls of bone, and the eye would then escape. They are real walls of defense to the eye. A stick can not hit HOW THE EYE IS GUARDED. 53 The winking muscle. * The eye’s cushion of fat. the eye itself unless it goes with its end pointed to the eye. It must go in this way to avoid striking on these walls, or para- pets of bone, by which the eye is surrounded. But if the stick gets by these bony walls, it may not hurt the eye, after all. Perhaps you never thought what use there is in being able to wink so quickly. See what winking does. It shuts the eyelids over the eye, so that nothing can get into it unless it is something sharp enough to pierce through the lids. And a blow will not hurt the eye, if the lids are closed, unless it is hard enough to bruise it through the lids. How quick is the working of that winking muscle ! The mo- ment that the eye sees any thing coming toward it that may in- jure it, this muscle shuts up the eye out of sight as quick as a flash. It hardly seems as if there was time for a message to go from the eye to the brain, and then another back from the brain to that muscle in the lids. t But all this happens. The nerve of the eye tells the mind of the danger, and the mind sends a mes- sage to the winking muscle. This is done so quickly that when- ever people speak of any thing as being done very quickly, they are very apt to say that it was done in the twinkling of an eye. This expression is used in the Bible in this way. But I have not told you all that this winking muscle does. It does something more than shut the eye in. It pushes it back in its socket, so that it is a little farther out of the way of a blow. And it does not push it right against the hard bone of the socket : there is a soft cushion of fat for it to press the eye against. And this is not all. When the eye sees a blow coming, this 54 HOW THE EYE IS GUARDED. The winking muscles raise cushions over the eye to defend it. .muscle acts so strongly that it wrinkles the skin of the eyelids, and pulls down the eyebrow, and draws up the cheek, as you see here. Now see how this guards the eye. The cheek and the eye- brow are brought so near together that there is but little room for the blow to get at the eye ; and even if it does, the wrinkled skin of the lids makes a cushion over it that breaks the force of the blow. You can see that the blow would be much more apt to do harm if the winking muscle merely brought the lids together. As it is, a blow commonly hits on the eyebrow or cheek, or both, while the eye is safe, shut up and pushed back in its cavern upon its cushion of fat. To see how much the bringing together of the cheek and eyebrow defends the eye, you must look at some one as he forci- bly closes the eye, as represented in the figure. And if, at the same time, you put your finger on the parts, you will see how the cushions which all this wrinkling makes over the eye and about its socket defend it from harm. So you see that not only is the eye guarded by parapets of bone, but the busy winking muscle raises up cushions on them whenever the eye sees a blow coming. These cushions often save the bone from being cracked, and in this way also keep the eye from being hurt. HOW TIIE EYE IS GUARDED. 55 The eyebrows. The eyelashes. How the tears defend the eye. Of what use do you think the hairs on the eyebrows are? They are for good looks, you will say. But they are for some- thing more than this ; they are a defense to the eye. How this is I will explain to you. You know what the eaves of a house are for when there is no trough to the roof ; they keep the rain from running down from the roof on the sides of the house. They make it drop off to the ground a little way from the house. Just so the hairy eyebrows make the sweat of the forehead drop off upon the cheek, instead of running down into the eye. The eye- brows, then, are the eaves of the roof of the eye's house. Perhaps you will ask what hurt the sweat would do if it should run down into the eye. It would be very disagreeable ; and, be- sides this, it would irritate the eye and make it red. The eye would become inflamed. The eyelashes, too, besides making the eye look well, are a de- fense to it. You know that there are often small things flying about in the air which we are not apt to see. If these fly against the eye, they generally hit against the eyelashes, and so are pre- vented from going into the eye. The tears, also, are a defense to the eye. If any thing happens to get by the eyelashes into the eye, how quick the tears flow to wash it out ! Commonly the gland, or tear factory, only makes enough tears to keep the eye a little moist ; but as soon as any thing gets into the eye and irritates it, the tear factory sets to work briskly, and sends down the tears abundantly. At the same time, the winking muscle keeps moving the lids, and generally what is in the eye is soon washed out. 56 HOW THE EYE IS GUARDED. The sink-drain of the eye. In weeping the tears overflow their banks. Tears are flowing into the eye all the time. If they did not, the eyeball and the inside of the lids would become dry, and they would not move easily on each other. You would have to keep wetting them with water to prevent them from rubbing. The tear factory, which is just above the eye, continually sends down, through some little tubes or ducts, just enough tears to make the motion of the eye and the lids easy. But you will ask where the tears that are made go. They do not commonly run out over the lids, and they must go some- where. I will tell you about this. If you look at the eyelids of any one, you can see in each lid a little hole at the end of the edge toward the nose. The tears go into these holes, and down through a duct that ends in the nose. This duct may be called the sink- drain of the eye, for the tears, after washing the eye, run off through it. The two little holes or mouths in the lids commonly take in all the tears as fast as they come to them ; but when we cry, the tear factory makes tears so fast that these mouths can not take them all in. The tears, therefore, overflow their banks — the lids — and run down on the cheek. Questions. — Is the eye in a very exposed situation? Why is it seldom much hurt ? Are the parts about it often hurt ? Tell how the bones about the eye de- fend it. Of what use is winking ? What is said about the quickness with which it is done ? What else does the winking muscle do besides shutting the eye ? What does it push the eye back upon ? What else does this muscle do besides what has been mentioned ? How does this defend the eye ? On what does a blow aimed at the eye commonly hit ? Of what use are the hairs on the eyebrows ? What harm would the sweat do if it ran down into the eye ? Of what use are the eyelashes ? In what ways do the tears prevent the eyes from being injured? Where do the tears go to from the eye ? What happens when one cries ? HEARING. 57 What sound is. The experiment of scratching on a log with a pin. CHAPTER XIII. HEARING. What is sound ? If you look at a large bell when it is struck, you can see a quivering or shaking in it. If you put your hand on it, you can feel the quivering. It is this that makes the sound that we hear. You can see the same thing in the strings of a piano when they are struck, and in the strings of a violin as the bow is drawn over them. The wind makes the music on the iEolian harp in the window by shaking its strings. And when you speak or sing, the sound is made, as I have told you before, by the quivering of two flat cords in your throat. But when a bell is struck, how does the sound get to our ears ? The quivering or vibration, as it is called, of the bell makes a vi- bration in the air, and this vibration is continued along through the air to our ears. The vibration can go through other things besides the air. It will go through something solid better than it will through air. Put your ear at the end of a long log, and let some one scratch with a pin on the other end, you can hear it very plainly. The vibration made by the pin travels through the whole length of the log to your ear ; but if you take away your ear from the log you can not hear it, for the vibration or sound can not come to you so far through the air. The nearer you are to where the sound is made, the louder it is ; 58 HEARING. Dying away of sound. Speaking tubes. and the farther sound goes, the fainter it is. It is said to die away as it goes ; that is, the vibration becomes less and less, till, after a while, it is all lost. It is like this : if you drop a stone into water, it makes little waves or ripples in all directions. These become less and less the farther they go from where the stone was dropped. It is just so with the waves or vibrations of sound in the air. What is an echo ? It is when a sound that you make comes back to you again. It is done in this way. The vibration strikes against some rock, or house, or something else, and then bounds back to you, just as a wave striking against a rock bounds back. Why is it that a person speaking in a building can be heard more easily than one speaking in the open air ? It is because the vibrations are shut in by the walls. It is for the same reason that you can hear a whisper so far through a speaking tube ex- tending from one part of a building to another. The vibrations are shut in within the tube. They have no chance to spread out in all directions, and they go right straight on through the tube. I have thus told you how sound is made, and how it goes through the air and through other things ; but how is it that we hear sound when it comes to our ears ? How does the mind know any thing about the vibration of the air ? This vibration does not go into the brain, where the mind is ; it only goes a little way into the ear, and there it stops. It comes against the drum of the ear, and can go no farther. How, then, can the mind know any thing about it ? This I will tell you. The vibration of the air goes into the ear to a membrane fast- HEAEING. 59 The bones of the ear. The different vibrations in hearing. ened to a rim of bone, and called the drum, and shakes it, and this shakes a chain of little bones that are the other side of this drum-head. The last of these bones is fastened to another little drum, and, of course, this is shaken. This drum covers an open- ing to some winding passages in bone. These passages are tilled with a watery fluid. Now the shaking of the second little drum makes this fluid shake. The nerve of hearing feels this shaking of the fluid, and tells the mind in the brain. Here are the four little bones that make the chain of bones in } the ear. They are curiously shaped. The one J marked a is called the hammer, and b is called the anvil. The little bone marked c is the smallest JL-— u bone in the body. That marked d is called the stirrup. This is the bone that is fastened to the second drum — the one that covers the opening into k the winding passages. The vibration that comes to the first drum is passed on by this chain of bones to the sec- ond drum. See, now, how many different shakings there are for every sound that you hear. First, the bell, or whatever it is that makes the sound, shakes. Then there is a shaking of the air. This shakes the drum of the ear. Then the chain of bones is shaken. The farthest one of them shakes another drum, and this shakes the fluid in the bony passages. All this happens every time that you hear a sound ; and when you hear one sound after another com- ing very quickly, how the vibrations chase each other, as we may say, as they go into the ear ! But they are not jumbled together. 60 HEARING. Different sizes of ears in animals. Ear-trumpet. They do not overtake one another. Every vibration goes by it- self, and so each sound is heard distinct from the others, unless the vibrations come very fast indeed. Then they make one con- tinued sound. Each puff of a locomotive, when it starts, is heard by itself. The vibration of one puff gets into the fluid in the bony passages before the one that follows it ; but as the locomotive goes on, the puffs get nearer and nearer together, and when it goes very fast, they are so near together that the vibrations do not go sep- arate into the ear, and they make a continued sound. Sound, I have told you, spreads in all directions in vibrations or waves. Now the more of these waves the ear can catch, the more distinct is the hear- ing. Some animals that need to hear very well have very large ears. Here is one, the long-eared bat. He must hear very well indeed, for his mon- strous ears must catch a great many of the waves of sound. We could hear better if our ears were larger ; but large ears would not look well on our heads ; and we hear well enough commonly. Sometimes, when we do not hear as distinctly as we wish to, we put up the hand to the ear, as you see represented on the oppo- site page. This helps the hearing by stopping the waves of sound, and turning them into the ear. Those who are very deaf some- times have an ear-trumpet, as it is called. In using it, the large HEARING. 61 Ears of rabbits, deers, etc. How the ear is guarded. trumpet end is turned toward the per- son speaking, so as to catch the vi- brations, while the tube part of it is in the ear. Some animals can turn their ears so as to hear well from different direc- tions. How quickly the horse pricks up his ears when he sees or hears something that he wants to know more about ; and then he can turn his ears backward when he wants to do so. It is in such timorous animals as the hare, the rabbit, and the deer, that we see the ears most movable. They are on the watch all the time for danger, and the least sound that they hear they turn their ears in the direction of it. Their ears, too, are large, so that they hear very easily. I have told you how the eye is guarded. The ear is well guard- ed also. I do not mean its outer part : it is the inner parts, where the hearing is really done, that are so well guarded. You remem- ber that I told you that there are passages filled with a fluid. The nerve of hearing has its fine, delicate fibres in these passages. They feel the shaking of the fluid, and tell the mind of it. Now it is necessary that this part of the hearing apparatus should be well guarded ; for this reason, these passages are inclosed in the very hardest bone in the body. Then, too, the very entrance into the ear is well guarded, and in a curious way. The pipe that leads into the drum of the ear 62 HEARING. How the ear-wax guards the ear. is always open, and you know bugs are very apt to crawl into such holes. What do you suppose is the reason that they do not often crawl into the ear? There is something there to prevent them. It is the wax. They probably do not like the smell of it, and so, if they come to the entrance, they turn about. Once in a while one goes in, and then he is prevented from doing much harm by the wax. He is soon covered with this, and it is so sticky that it keeps him from kicking very hard. And, after all, though he may cause some pain, he can not get at the delicate part of the machinery of the ear. He dies after a while, if he is not got out, and perhaps the bitterness of the wax has something to do with killing him. Questions . — How is sound made ? How does it get to our ears ? Tell about the vibration of sound in a log. What is said about the dying away of sound ? What is this like? What is an echo? What is said about speaking in a building? What about speaking through a tube ? Tell how we hear sound. Tell about the little bones in the ear. What do these bones do ? Tell what the different vibra- tions are in hearing. What is said about the puffing of a locomotive ? Why do some animals have large ears? Why are our ears so small? What animals can turn their ears different ways, and why ? How is the inner part of the ear guard- ed ? Tell what is said about the wax. THE SMELL, THE TASTE, AND THE TOUCH. 63 How we smell things. CHAPTER XIY. THE SMELL, THE TASTE, AND THE TOUCH. I HAVE told you that most of what the mind knows about the world around it comes to it by the sight and the hearing. But it learns a great deal by the other senses, and these I will tell you about in this chapter. Did you ever think how it is that you smell any thing? You put a rose up to your nose, and the fragrance is pleasant to you. Now what is this fragrance ? Is it something that goes up into your nose ? You can not see any thing come from the rose. But in reality very fine particles come from it. They are finer than the finest powder. They float every where about in the air, and, as you breathe, they go with the air into your nostrils. Every perfume that you smell is made of such particles. But how do you think the mind knows any thing about these particles when they come into the nose ? It is in this way. In the lining of the nose are the fine ends of the nerve of smell. These ends of the branches of this nerve are so small that you can not see them. Now the fine particles that I have told you about touch these ends of the nerve, and the nerve tells the mind about them ; and this is smelling. The nose is a more extensive organ than most people think it is. There are divisions in it. These fold on each other in such a way that there is a great deal of surface in the nose, and the ends of the nerve of smell are all on this surface. 64 THE SMELL, THE TASTE, AND THE TOUCH. The smell of some animals. The enjoyment afforded by the sense of smell. Some animals have a very sharp smell. In them the divisions in the nose are very great in extent, and so the nerve spreads over a large surface. The dog, you know, is able to track his master by scenting his footsteps. The cat, too, has a very quick smell for rats and mice. Some persons have a sharp smell for some things. I have heard of a blind gentleman who could always tell when there was a cat any where near him by his sense of smell. Once he was very sure that there was one near by, though no one could see her; he insisted upon it that he was right, and after a while pussy was found in a closet of the room. There was also a blind and deaf person who could distinguish between different people that he knew by the sense of smell. The sense of smell affords us great enjoyment. The Creator has, for the purpose of gratifying us, scattered sweet-smelling flowers all over the earth. These are all perfume factories, as I told you in Part First, made by him to give us pleasure. He could have made the flowers and fruits in such a way that they would have no smell ; but, in his desire to please us and make us happy, lie has given to them a great variety of pleasant odors. There are, it is true, some unpleasant smells in the world, but these are not any thing like as common as the pleasant ones ; and many of them are manifestly very useful in warning us of danger. For example, the unpleasant odor caused by filth and decay tells, people where these causes of disease are, so that they may get rid of them. And plants that are poisonous generally have a disa- greeable odor, which leads us to avoid them. THE SMELL, THE TASTE, AND THE TOUCH. 65 How we taste and how we feel. The sense of taste is another source of gratification to us. The nerve of this sense has its fine ends mostly in the tongue. What we take into the mouth touches these ends of the nerve, and the nerve tells the mind about it ; and this is tasting. Besides the pleasure which we have from the taste, the great use of this sense is to guide us in the choice of food. Animals choose the kinds of food that are proper for them, and they do it by their taste. They very seldom make a mistake in this. The sense of taste, like that of smell, sometimes warns us of danger. If our food tastes bad, we know that there is something wrong about it* and do not eat it, and so, perhaps, avoid being made sick. The sense of touch gives a great deal of knowledge to the mind. This sense has a large number of nerves in all parts of the body, and they are making reports continually to the mind. Especially busy in this way are the nerves of the tips of the fingers. It is by the fine ends of these nerves that the mind finds out how dif- ferent things feel. It finds out whether they are soft or hard, smooth or rough, etc. These nerves in the tips of the fingers are of great service to the mind in guiding it in using the muscles. In playing with the fingers on an instrument, the feeling in the ends of them is a guide to the mind in working them. So it is with any thing that we do with them. You could not do some of the simplest things if there was no feeling in your fingers. You could not even button and unbutton your coat. I shall have more to say about this when I tell you particularly about the hand. The nerves of touch are not placed on the surface of the skin. 9 E 66 THE SMELL, THE TASTE, AND THE TOUCH. The nerves of touch in the skin. How some animals feel. We have really two skins, an outer and an inner one. The nerves are in the inner skin, and are covered by the outer skin. This outer skin is very thin except on the sole of the foot and the palm of the hand; from its thinness it is called the scarf-skin. It is this which is raised when a blister is drawn ; and perhaps you know that it does not hurt to prick this when we want to let the water out ; but if the needle touches the inner skin, where the nerves are, you feel it very quickly. Now, when you touch any thing, the nerves in the inner skin feel it through this scarf-skin. This is so thin and soft that the nerves can feel through it ; and, at the same time, it is a good pro- tection to them. If it were not for this, the nerves would be af- fected too much by the rubbing of things against them. They could not even bear the air. If you had no scarf-skin you would be in great distress all the time. You know how much pain you suffer if you rub off the skin, as it is called, any where. It is the scarf-skin only that is rubbed off, and this exposes to the air the fine ends of the nerves in the inner skin. The ends of the nerves of touch are in rows on the tips of the fingers. It is these rows that make the curved lines that you can see so plainly. There are no animals that have such perfect instruments of touch as our fingers, are. Animals that have hoofs, as the horse and the cow, can not feel much with their fore feet. They have their senso of touch mostly in their lips and tongues. The elephant has this sense chiefly in the finger-shaped thing at the end of his trunk. There is not much feeling in the paws of dogs, cats, etc. The THE SMELL, THE TASTE, AND THE TOUCH. 67 Whiskers of the ra t. Feelers of insects. whiskers of the cat are feelers. There are nerves at the root of each of those long hairs, so that when any thing touches the whis- kers the cat’s mind knows it at once. Insects have feelers extending out; from their heads. Some- times they are very long, as you see in this insect, called the ich- neumon fly. We see insects, as they are going about, touch things with these feelers as we do with our hands. Bees can work in the dark, in their hives, guided by their feelers ; indeed, the bee will not work at all if his feelers are cut off : he does not seem to know what to do with himself. In- sects sometimes appear to tell each other things by their feelers. In every hive of bees there is a queen. If she dies, those that know about it go around very quickly, telling the other bees by striking their feelers with their own ; and those that are told tell others, and thus the sad event is soon known all over the hive. Questions. — By which senses does the mind get most of its knowledge ? What is fragrance ? How does the mind know any thing about it ? What is said of the extent of the organ of smell ? What is said of the smell of some animals ? Of the acute smell of some persons ? What is said of the enjoyment afforded by the sense of smell ? How are offensive odors sometimes useful ? What is said of the sense of taste ? What are its uses ? Where is the sense of touch ? Where is it espe- cially active ? What do the nerves of touch in the fingers tell the mind ? In what way do they help us in using the muscles ? Tell about the two skins of our bodies. Why is the outer skin needed ? What makes the curved lines on the tips of the fin- gers ? What is said of touch in animals that have hoofs ? What are the whiskers of the cat for ? What is said of the feelers of insects ? What is told about the bees ? 68 THE BONES. IIow the mind uses what it learns. CHAPTER XV. THE BONES. I HAVE told you, in the last few chapters, how it is that the mind learns about the world around it by the senses. But the mind does something besides learn. It tells others about what it learns. It does this by the muscles in various ways. When you tell any thing by speaking, it is the muscles of the throat, and mouth, and chest that do it. When you write, the muscles of your hand are telling what the mind directs them to tell. When your face expresses your thoughts and feelings, it is the muscles of the face that tell what the mind thinks and feels. The mind not only tells things, but it does things also, and it does them by the muscles. You see a man busily at work mak- ing something : his muscles are doing the work. The mind is di- recting them how to do it by the nerves that spread to them from the brain. How does his mind know in what way to direct them ? It is by knowledge gained through the senses — by his eyes and ears. He has seen people do the same kind of work and they have told him about it. His mind uses with the muscles what it has learned by the senses. You see, then, that the mind makes use of what it learns by the senses in two ways : it tells about it, and it uses it in doing things ; and in both telling and doing it uses the muscles. Our knowl- edge, then, goes into the mind by the senses — they arc its inlets ; THE BONES. 69 The joints of the hones. The oiling of them. but it comes out by the muscles — they are its outlets . If a mind were in a body that had the senses, but had no muscles, it might know a great deal, but it could never let any body know what it knew, and it could not do any thing. The chief things that are moved in the body by the muscles are the bones, and I shall tell you about these before I tell you about the muscles. When you bend your arm, the muscles make the bones in the lower part of the arm bend on the bone in the upper part. There is a joint at the elbow for this purpose ; and there are joints in many other parts of the body, so that the muscles can move one bone upon another. These joints of the bones are so contrived that they do not wear out. They work nicely through a long life. Now it would be very strange if a joint in a machine should work all the time for seventy or eighty years, and still be almost as good as new 0 No man ever made such a joint. You know that men keep oiling the joints in machinery. If they did not, the joints would soon wear out. When the cars stop at a station, you see men with tin vessels oiling the boxes of the wheels of the locomotive and the cars, and other parts that rub on each other. The joints of our bones need no such care from us. We never need to oil them as men oil machinery. They are very nicely made. The ends of the bones are tipped with a very smooth substance, and this is always kept in good order; and then, too, the joints always keep themselves oiled. How this is done I explain in a book for older scholars. 70 THE BONES. Bones of the head. Bones of tho chest. The bones are the framework of the body. They are to the body what whalebones are to an umbrella, what timbers are to a house, or what the ribs of leaves are, as I told you in Part First, to the leaves. The bones make the body firm. You could not stand up if you had no bones ; you would have to crawl like the worm. See one bracing himself to pull or push. The bones are all pressed tightly against each other by the strong muscles. The bones of the body have very different shapes and sizes. Let us look at some of them. The bones of the head, represented here, make a roundish box. This is to hold the brain. Here the mind, the governor of all the machinery of the body, resides. Great care is therefore taken to guard well this upper room of the body. Its bony walls are made very strong. Look at this barrel-shaped set of bones that make the chest. The ribs go round it as hoops do round a barrel. They are joined to the back bone behind and to the breast bone in front. They are joined to the back bone in such a way that they move up and down as you breathe. You can feel them move upward if you put your hand on your chest as you take a full breath. Inside of this barrel-shaped set of bones are the heart and lungs. THE BONES, 71 Back bone. Bowing. Position of the head. The back bone, as we call it, is not one bone ; it is a chain or pile of twenty-four bones placed one above another. You can see a part of this pile or column, as it is sometimes called, in the fig- ure of the bones of the chest. If it were all one bone, you could not twist your body about as you do. And in making a bow, you could not bend your back. You could only bend your head for- ward on the top of the back bone, and bend your body forward on your lower limbs. A very awkward bow that would be. As it is, whenever you make a bow, there is a little motion between each two of the whole twenty-four bones, and this makes the bow easy and graceful. Persons that bow stiffly do not have enough of this movement in the column of bones, but move it altogether, very much as if it were all one bone. The head rests on the top of this column of bones. When you move your head backward and forward, it rocks on the topmost bone of this column. There are two little smooth places hollowed out on this bone for it to rock on, and the head has two smooth rockers that fit into these places. Questions. — In what two ways does the mind nse what it learns ? With what does it do this ? What are the inlets of the mind’s knowledge ? What are its out- lets? What move the bones on each other? What is said about the wearing of the joints ? What is said about their being kept oiled ? What are the bones to the body ? What is said about the bones of the head ? What of the bones of the chest ? To what are the ribs fastened behind ? To what in front ? How many bones are there in what is called the back bone ? Why are there so many ? What does the head rest on ? What is said about the motion of the head ? 72 MORE ABOUT THE BONES. Bones of the arm and hand. Shoulder joint and elbow joint. CHAPTEE XVI. MORE ABOUT THE BONES. Here are the "bones of the arm and the hand. The head of the arm bone that goes into the socket at the shoulder is, as you see, a smooth rounclball. It fits into a sort of cup. The joint here is what we call a ball-and-socket joint The ball turns in the socket very easily in making any whirl- ing motion with your arm, as you do when you jump the rope. The joint at the elbow is of a different kind : it is what we call a hinge joint. You can not make any whirling motion at your elbow as you can at the shoulder ; the mo- tion is all one way, like a hinge. The chief motion at the wrist also is a hinge motion, as you can see by working your hand back and forth. There are two bones, you notice, in the MORE ABOUT THE BONES. 73 Bones of the leg and foot. arm below the elbow : these roll on each other in such a way that you can turn the palm of your hand in different directions. There are a great many little bones in the body of the hand and in the fingers. There is a very great variety in their motions, so that the hand can do almost any thing that you want it to do. I shall have something more to tell you about this when you come to the chapter on the hand. You have here the bones of the leg and foot. You see only the lower end of the stout thigh bone, at the knee joint : it makes a hinge joint with the large bone of the leg. The motion of this joint is only one way, backward and forward, as you see in walking. The small, thick bone, called the knee-pan, is left out in the figure. One of the uses of this bone is to be a shield to the joint. If you fall down in running, you are apt to come upon the knee, and this shield keeps the joint from being hurt. You see that long, very slender bone at the side of the large one : one would suppose that this would be very easily broken, but it is not, because it is so well covered up with muscles. Its lower end is quite thick and strong, and makes the outer part of the ankle. The ankle joint is a hinge joint like that of the knee. 74 MORE ABOUT THE BONES. Why there are so many bones in the foot. Skeleton of the bat. There are as many bones in the foot as there are in the hand. Why is this ? You remember that I told you that the hand had so many bones because it had to perform so many different mo- tions. But it is not so with the foot ; it does not have much va- riety of motion. There is some other reason, then, for its having so many bones. It is this. If the bones of the foot were all in one, the foot would be a very stiff and clumsy thing ; it would not be springy as it is now. You would make awkward work in walking and running with such feet. The bones of different animals are made differently, according to the work which they do. Those that do heavy work have heavy, stout skeletons ; but those that have only light w T ork to do have their bones slender. A bird has a light skeleton, for it could not fly so well with a heavy one. Here is the skeleton of a bat. The bones are exceedingly light and slender, for it is light and nimble work that he does in flying. The bones in an old person are more brittle than those in a child. If the child’s bones were brittle they would be very often broken, because he so often tumbles down. If old per- MORE ABOUT THE BONES. i O The bones of a child’s head. Why we have two sets of teeth. sons were as careless as children are, there would be broken limbs to be taken care of in almost every house. They would not get off with a short crying spell and a bruise, as children commonly do when they have a fall. There is one contrivance in the child’s head that prevents the bones from breaking in its frequent falls. In the grown person the bones of the head are fastened tightly together, and are almost like one bone. But it is not so with the child. In an infant’s head they are very loose, and you can feel quite a space between the bones at the top of his forehead. Now, when the child falls and hits his head, the loose bones give and do not break. Though the teeth are like the bones, they are different from them in one thing. The bones grow with the rest of the body, but the teeth never grow any larger than they are at first. When the tooth first pushes up through the gum, it is as large as it ever will be. Look at the reason of this. The outside of the tooth — the enamel, as it is called— is made very hard. It needs to be so, that the tooth may do its work well. Such a hard substance, when once made, is finished. It never can grow. No blood can get into it to make it grow, as it can into the bones. And now you see the reason that every person has two sets of teeth. If the teeth that one has when a child should remain in his head, they would be too small for him when he became an adult ; and as the jaws grew they would become quite far apart, and so would look very strange. To get rid of these difficulties, the first set begin to be shed about the seventh year, and a new set of larger teeth take their places. As the new teeth are not 76 MORE ABOUT THE BONES. Skeletons of crabs and lobsters. How they are shed every year. only larger, but are more in number, they fill up all the room de- signed for them in the enlarged jaws. All the bones of our bodies are inside, and are covered with muscles, cords, and ligaments ; and over all is the skin. But the bones of some animals are outside. This is the case with crabs and lobsters. Their bones make a sort of coat of mail to defend the soft parts from being injured. The hard coats of many insects also may be considered as their skeletons. Such animals as crabs and lobsters have new skeletons every year. The old skeletons are too small for their growing bodies, and so they must be cast off. The animal crawls into a retired place to go through the operation. It is painful, and sometimes proves even fatal. He makes a great effort, and the shell comes apart. He then, by hard struggling, pulls himself out. He now keeps still a few days in his retirement, and another case or skel- eton, as hard as the old one, is formed. When he comes out with his new armor on, he is as brave and as ready to fight as ever. Questions . — What is said about the shoulder joint ? The elbow joint ? The wrist ? How is it that you can turn the palm of the hand one way and another ? Why are there so many little bones in the hand ? What is said about the knee joint ? What is one of the uses of the knee-pan ? What is said about the slender bone in the leg ? What about the ankle joint ? Why are there so many bones in the foot ? What is said of the difference in brittleness between the bones of the old and of the young? What is said about the bones in a child’s head? How are the teeth un- like the bones ? Why do we have two sets of teeth ? What is said about the bones of some animals ? What is related of crabs and lobsters ? THE MUSCLES. 77 IIow the muscles act. The muscles that bend and straighten the arm. CHAPTER XVII. THE MUSCLES. I have already told you some things about the muscles. There is no motion in the body that is not made by them. They move the bones, and they move other parts also, as the tongue, the corners of the mouth, the eyes, the eyelids, etc. But you will want to know how they do this. Stretch a strip of India-rubber with your hands. Now let it go, and it will shorten itself. When a muscle pulls a bone, it shortens itself just as this strip of India-rubber does. But the cause of its shorten- ing itself is different. The mind makes the muscle shorten. You think to bend your arm ; and, as quick as thought, some- thing goes by nerves to the muscle that can do this, and it short- ens itself and bends the arm. Here is a figure that shows the muscle that bends the arm, and also the muscle that straightens it out. All the other muscles of the arm are left out, so that you may see just how these operate. Look at the muscle marked a : you can see that when this short- 78 THE MUSCLES. Color of muscles in different animals. Muscles that move the fingers. ens itself it must pull up the forearm, that is, that part of the arm which is below the elbow. The muscle b has a contrary effect. The end of this muscle is fastened to the point of the elbow, and when it shortens it pulls the forearm down and straightens the arm. When a muscle shortens itself, it swells out and becomes hard. Straighten your arm, and then take hold of it with your other hand a little above the elbow ; now bend up your arm as forcibly as you can, and you will feel the muscle on the front of the arm swell out and harden as you hold your hand upon it. The muscles are the fleshy part of the body. The meat of an- imals is made up of muscles. They are not of the same color in all animals. In some they are quite red, while in others they are of a light color. Beef — the meat of the ox or the cow — is, you know, a deep red, and is very different from the meat of a fowl. The muscles of fishes are generally very light in color. Your arm below the elbow is very fleshy. Most of the mus- cles that move the fingers, as well as those that move the hand, are there. Take hold of that part of the arm with your other hand while you work the fingers back and forth, and you will feel the muscles as they shorten themselves to pull the fingers. Here is a figure showing the muscles in this fleshy part of the THE MUSCLES. 79 Muscles in the hand. The round fullness of the arm. Drum-stick of the fowl. arm. You see that they are quite large. The wrist is very slen- der. There are no muscles there; there are bright, shining, smooth cords there, that run from the muscles to the fingers. The mus- cles pull the fingers by these cords just as men pull any thing by ropes. You can see the play of these cords very plainly on the back of the hand of a thin person as the fingers are worked. There are only some very small muscles in the hand, as those that spread the fingers out, and those that bring them together again. If you work your fingers in this way, you will see that the muscles, which do such light work, need not be large and strong. The muscles that do the hard work of the hand are up in the arm. They are very large. If they were not, you could not grasp things so tightly, and pull so hard as you sometimes do. Now see why it is that these large muscles are put so far away from where they do their work. If they were put in the hand, they would make it a large and clumsy thing. They are there- fore put up in the arm, where there is room for them, and they have small, but very strong cords by which they pull the fingers. They give to the arm that round fullness that makes its shape so beautiful. You can see the same kind of arrangement in the drum-stick, as it is called, of the fowl. The large muscles that work the claws are up in the full, round part of the leg, and there are small, stout cords that extend from them down to the claws. Children often amuse themselves with pulling these cords in the drum-stick of a fowl, making the claws move just as they are moved by the muscles of the animal when he is alive. 80 THE MUSCLES. Muscles of the toes. Ligaments of the wrist and the ankle. It is with the muscles that move the toes as it is with those that move the fingers. They are put mostly up in the leg, and their slender tendons, by which they pull, go down over the ankle to the toes, just as in the arm the tendons go over the wrist to the fingers. If the muscles of the toes were all put in the foot, they would make it very clumsy, and at the same time the leg would be ugly from the want of that fullness which it now has. Both at the wrist and the ankle the tendons are bound down / very tightly. If this were not so they would be always flying out of place, stretching out the skin before them in ridges. This would be the case especially with the tendons that go to the toes. Every time that the muscles pulled on them, they would start out very much at the bend of the ankle if they were not firmly held by the ligaments. 0 The muscles are of many shapes — round, flat, long, short, etc. They are shaped to suit the work which they are to do. They vary much in size also. Some are very large, and some are exceedingly small. How large are the muscles of the arm that wield the hammer and the axe ! But how small are the mus- cles that work the musical cords in your throat when you speak or sing ! These little muscles make all the different notes of the voice by pulling on these cords, and in doing this many of their motions are exceedingly slight. You remember that in the chapter on the hearing I told you about the little bones in the ear. These have some very little muscles which move them. The bones and the muscles, a and 6, are represented in the following figure. The muscles, you see. THE MUSCLES. 81 Muscles in the ear. Large and small muscles in birds. have tendons or cords to pull by, in the same way that the muscles in the arm have. Both the bones and the muscles are larger in this figure than they are in the body. As the bones are the smallest ones that we have, so b it is with the muscles. Very small machinery is this part of the hearing machinery. The birds that go swiftly on their wings have very large muscles to work them. This gives them the full, round breast which you see that they have. But the muscles that work the musical cords in their little throats, as they sing so sweetly, are so small that it is difficult to find them. Questions . — By what is all motion in the body made ? What do the muscles move ? Explain how the muscles move things. Tell about the two muscles of the arm in the figure. What is said about the swelling out of the muscles as they short- en ? What is the meat of animals ? What is said about the color of muscles in different animals? What is said of the muscles in the arm below the elbow? What is said of the wrist ? What of the muscles in the hand ? Why are most of the muscles that move the fingers put up in the arm ? What is said about the drum-stick of a fowl ? What is said about the muscles of the toes ? What about the ligaments of the tendons at the wrist and ankle ? What is said of the shapes of muscles? What of their sizes? What are the smallest muscles in the body? What is said about the muscles of birds used in flying and those used in singing ? 2 F 82 MORE ABOUT TIIE MUSCLES. Number of muscles in the body. All connected with the brain by nerves. CHAPTER XVIII. MORE ABOUT THE MUSCLES. There is a great number of muscles in the whole body to pro- duce all its motions. There are about fifty in each arm and hand. In the whole body there are about four hundred and fifty, and each muscle is made up of a great number of fibres or threads, every fibre having its own work to do. Now all these muscles have nerves that connect them with the brain, and the mind tells them by these nerves just what to do. Each muscle has a great many little nervous ends scattered through it every where. The message from the mind that tells the mus- cle to act does not go to the whole muscle as one thing, as a mes- sage is sent to a person. It goes to each fibre of it, telling that fibre what to do. Every fibre of the muscle has its little nervous tube connecting it with the brain, for the nerves are bundles of tubes, just as the muscles are bundles of fibres. And each fibre gets its messages from the mind separate from all the other fibres by its own tube, so that each fibre is a workman by itself. How well these workmen pull together when they all get a message from your mind by their telegraphic tubes ! Commonly it takes several muscles to make any motion, and sometimes many muscles act together. When this is so, mes- sages are sent to a great multitude of fibres in these many muscles. Think of this. Raise your hand. It is not one muscle that does MORE ABOUT THE MUSCLES. 83 The endless variety of messages sent from the brain to the muscles. this, but many. Your mind has sent a message to all the fibres of these muscles, and they have all done their part in raising your hand. But now raise it again a little differently. A different message for this has been sent to all the fibres ; and so for all the different motions there are different messages. It does not seem possible that so many different messages should be sent through the nerves to the fibres of all the muscles, and that these fibres should obey them so perfectly. This is wonderful even in so simple a motion as raising the hand; but how much more wonderful when a great variety of rapid motions are made by the muscles, as in playing on a piano ! How busy is the mind of the playftr in sending its messages, one after the other, to the multitudes of muscular fibres that work the arms and the fingers ! And if he sings at the same time that he plays, his mind is sending messages also to the muscles of the chest, and throat, and mouth. And what adds greatly to the wonder is, that all this time that the mind is sending out so many messages, it is receiving messages from the senses. Messages are going from the sounds of the piano and the voice along the nerves of the ear to the mind. They go also from the tips of the busy fingers as they press the keys. How wonderful that all these messages are going back and forth so rapidly, and the mind in the ~ brain manages them without any confusion ! I have told you that there are some parts besides bones that are moved by muscles. Different parts of the face are moved by them, and it is this that gives it its different expressions. Thus, when you are pleased and laugh, the muscles pull up the corners 84 MORE ABOUT THE MUSCLES. The muscles used in smiling and laughing. of the mouth. If you laugh very hard, they pull them up very much, as you see in the face drawn here. See how this face is wrinkled under the eyes. This is because the muscles pull at the corners of the mouth so hard as to push up the cheeks. What do you think the difference is between laughing and smiling ? It is this. In laughing, the corners of the mouth are drawn up a good deal, but in smiling they are drawn up only a little. Most people think that the eyes have a great deal to do with laughing and smiling, and they talk about a laughing eye and a pleasant eye. But this is not correct. It is these muscles, which pull up the corners of the mouth, that make the eye look pleasant and laughing ; indeed, laughing and smiling can be done with the eyes shut. We often see a beautiful smile in the face of the sleeping infant. It is because some pleasant dream in his mind plays on the nerves that go to his smiling muscles. There are muscles to pull the corners of the mouth down, and these make the face look sad ; and if the muscles that wrinkle the eyebrows act at the same time, the face is both sad and cross, as MORE ABOUT TIIE MUSCLES. 85 The sad muscles “ Down in the mouth.” The proud muscle you see here. Observe just what the difference is be- tween this face and the laughing face on the oppo- site page. The difference is merely in the corners of the mouth and in the eyebrows. In this face the two wrink- lers of the eyebrows are in action, and so are the two muscles that pull down the corners of the mouth. F our small muscles, then, make this face sad and cross. But in the laughing face the eyebrow-wrinklers are quiet, and the cor- ners of the mouth are pulled up instead of being pulled down. It is the two little muscles that pull up the corners of the mouth that do all the laughing in the face. You have often heard the expressions, “ He had a down look,” and “His countenance fell.” These refer to the effect produced by sadness on the corners of the mouth. This explains also the meaning of the common expression, “Down in the mouth.” There is a certain muscle called the proud muscle. It pushes up the under lip. It is chiefly by this that pouting, that ugly expression so common with some children, is done. When the eyebrow-wrinklers act at the same time, there is scowling with the pouting, and then the face is very ugly. I beseech of you 8G MORE ABOUT THE MUSCLES. Snarling muscles, The smiling of the dog. The chief muscles of expression. not to get into the habit of using these cross muscles. Keep al- ways pleasant and kind, and then those nice little muscles that draw up the corners of the mouth will always be ready to light up your face with a cheerfulness that shall be pleasant to look upon. There are some animals that have certain muscles in the face that we have not. These are the snarling muscles. They pull up the lip at the sides of the mouth so as to show the long, tear- ing teeth. You see them in operation in the dog, the tiger, etc., when they are angry. No animal but man has in the face either the frowning, or the sad, or the smiling muscles. Perhaps you will say that the dog smiles when he is pleased and looks up at his master. He smiles, it is true, but he does it only with his wagging tail, for he has no muscles in his face to do it with. How wonderful is the variety of expression in the human face ! And yet all is caused by a few muscles, and the principal ones are those that draw up and draw down the corners of the mouth, and those that wrinkle the eyebrows. . Questions . — How many muscles are there in the arm and hand ? How many in the whole body? What is each muscle made up of? What is said of the fibres? Is it common for a motion to be made by one muscle alone ? What is said about raising the arm in different ways ? What is said about the variety of rapid mo- tions that are sometimes performed ? What gives the face its different expressions ? How is laughing done ? What makes the wrinkling under the eyes in laughing ? What is the difference between laughing and smiling ? Has the eye any thing to do with them? What is said about the sad muscles? What about the cross ones? What is the difference between a cross and sad face and a laughing one ? What is said about certain expressions in common use ? What is said about the muscles of expression in the face of animals ? What is said of the variety of expression in the human face ? THE BRAIN AND NERVES IN ANIMALS. 87 The brain the mind’s central workshop. How animals learn. CHAPTER XIX. THE BRAIN AND NERVES IN ANIMALS. I have told you liow your mind learns about the world around you, and how it makes use of its knowledge by means of the ma- chinery of your body — the muscles, bones, etc. Your mind is in the brain, and uses the brain to think with ; and from the brain branch out all the nerves by which it works all the various ma- chinery of the body. Your brain, then, may be considered the central work-shop of your mind ; or it is like an engine-room of a factory, where the engine is that keeps the machinery in other parts of the building in motion. The different animals have a brain and nerves just as you have, and their minds in their brains learn about things around them. They do not learn so much as your mind does, it is true ; but they really do learn. If you look at a kitten when it is first born, it is very much like a baby. It does not know any thing. But, like the baby, it knows more and more every day, and when it gets to be a cat it knows a great deal ; and all that it knows has come to its mind in the same way as what you know has come into your mind. It has come in through its senses. All its knowledge came in at its eyes and ears, etc., and got to its brain by the nerves. The mind in animals, too, uses the muscles in the same way that your mind does. Watch a kitten at play. The muscles that 88 THE BRAIN AND NERVES IN ANIMALS. The mind of a kitten as it plays. The minds and brains of insects. move her paws are directed by her mind in the brain by means of the nerves. As she pokes at the thing that you hold out to her, the nerves of her eyes are telling the mind in the brain all the time about the string, and then the mind is telling the muscles of the paws what to do. See her as she springs to catch the string that you draw along on the floor. As she watches it, messages are go- ing from those bright eyes to her mind in the brain ; and then, as she springs, messages are sent from her brain to a great many muscles in different parts of her body. The mind tells the mus- cles just when and how to act, and they all do exactly as the mind tells them. The mind of a cat sets a great deal of machinery at work when she makes a spring to catch any thing. What I have told you about some animals is true of all. The little insect that flies out of the way when you strike at him has a little brain, and there his mind thinks about what it sees, and hears, and feels, etc., just as your mind does; and when he flies away so quickly from the blow that his eyes see coming, his mind tells the muscles to make the wings go. There are nerves that carry messages from his senses to the mind in his brain, and there are nerves that carry messages from his brain to his muscles, as there are in you. The brain is very small, and the nerves are very fine, but they do their work well. They make a little tele- graph, but it is a good one. What a quantity of thinking there is done in the brains of all the animals in the world ! How busy their minds are, receiving reports from their senses, and working all the machinery of their bodies. Go out into the garden, and see the birds, the butterflies, THE BRAIN AND NERVES IN ANIMALS. 89 Animals that think more than others have larger brains. the bees, the flies, the ants, the frogs, the toads, and the worms ; they are all busy thinking. They can not move without think- ing. It is their thinking that makes their muscles move them. And they think about what they move for. Some of them think more than others. The bird thinks more than the worm. Some think faster than others. The humming- bird, that darts so quickly from flower to flower, thinks as fast as he works. But the lazy toad is a slow thinker. His mind does not work the machinery of his muscles much, and so does but lit- tle thinking. But even he once in a while thinks quickly. Let a fly walk along pretty near him, and he will catch it with his tongue so quickly that you can not see just how he does it. He watches the fly intently, keeping very still all the while ; and when it gets near enough, he thrusts out his tongue, and the fly is gone. You would hardly think that so lazy-looking an animal could do any thing so quickly. But he is nimble as a fly-catcher, if he is not nimble at any thing else ; and very quickly must the mind in his brain think when it is working its fly-catching machinery. The more an animal thinks, the larger is the brain as compared with the rest of the body. Man thinks more than any other ani- mal, and so he has a large brain. But the oyster has hardly any thing that can be called a brain, for in his still life, shut up as he is in his shell, he thinks but little. But such animals as horses, dogs, cats, birds, monkeys, etc., have quite large brains, for they think a great deal. Their brains, however, are not, by any means, as large as the brain of man is in proportion to the size of the bodjr. 90 THE BEAIN AND NERVES IN ANIMALS. The brain compared to machinery. This is as we should suppose it would be. The brain is the machinery with which the mind thinks. Now, whenever we see a great deal of machinery together at work, we know that it is be- cause there is much to be done by it ; and when we see a small machine that has not many different parts, we know that it is not intended to do much. So it is with the mind’s thinking ma- chinery. The brain of an animal that thinks but little is small and simple ; but the brain of one that thinks much is large and has many parts. Though animals do their thinking with their brains as we do with ours, there is some thinking that we do that they can not. There are some things about which they know • nothing. But I will tell you about this in another chapter. Questions . — What does your mind do with your brain ? How is your brain like the engine-room of a factory ? What is said about the minds of different animals ? How is a kitten, when it is first born, like a baby ? How does it learn ? What is said about the mind, and brain, and nerves of an insect? What is said about the quantity of thinking done in the brains of animals ? How do some differ from oth- ers in their thinking? Tell about the toad. What is said about the size of the brain in different animals ? How is the brain compared with machinery ? THE VARIETY OF MACHINERY IN ANIMALS. 91 Machinery in the oyster suited to its wants. CHAPTER XX. THE VAKIETY OF MACHINERY IN ANIMALS. You have seen what a variety of curious machinery there is in our bodies for our minds to work, besides that which is needed to keep the body in repair. But I have told you some things about other animals as I have gone along. There is in them also a great deal of machinery, and it is different in each. The variety of it is wonderful. You see that the world is every where full of many kinds of animals, making it a very busy world. I do not believe that you have ever thought how different they are from each other. I will therefore tell you a little about this. See what a difference there is between man and some animals. Look at the oyster. He lives in the water, shut up in his rough shell. He is no traveler. He has no eyes to see sights with. He has no sense of smell. He has taste for his food, and, no doubt, enjoys it. He has the sense of touch ; this he needs, both to manage his food and to guard himself against harm. As he does not move about, and has no feet or hands, he has but few muscles. He has one to shut up his shell tight, which he does when he is alarmed. His brain and nerves are very small affairs, for he has little use for such things. There is little machinery, then, in an oyster, as you compare it with the machinery in your body ; and it is simply because he does not need so much as you do. If he had needed more, God 92 THE VARIETY OF MACHINERY IN ANIMALS. The hydra— all stomach and arms. How it acts when alarmed. would have given it to him. But there is, after all, considerable machinery even in the oyster. He has machinery for digesting his food. He has circulating machinery — a heart with its arteries and veins. And he has gills like fishes, by which his blood is aired by the air in the water. Then he has a few muscles, some nerves, and a sort of brain. Look, now, at another animal that has less contrivances in him than the oyster. Look at the hydra. This is a very little animal which is found in ponds, sticking to a straw or stick by a sort of sucker. Here is a representation of it. The small figure shows it of its natural size. The larger figure shows it as magnified by the microscope. This animal is little else than a stomach with long arms. We can turn the body of it — that is, the stomach, inside out, and the animal will do as well as before. The arms are merely to catch things, as worms and insects, which they put into the mouth of the stomach, marked a . One of the arms is represented as having caught something, which it is about to put into this mouth. When the little creature is alarmed, he gathers up all his arms around his stomach, and looks like a little ball. No brain has ever been discovered in him, but it is plain that he thinks some in catching his food, and in gathering himself into a ball to es- cape notice. He probably has a brain to think with, though it THE VARIETY OF MACHINERY IN ANIMALS. 93 One of the arms of the hydra magnified. Contrivances in animals endless. is so small that it is not to be seen with the most powerful mi- croscope. Here is one of the arms of this animal as seen with a powerful microscope. It is made up of little cells or blad- der-like things. How it is that these make the different motions of this arm we do not know. The two animals that I have just told you about are very unlike to man, but they are not more so than a mul- titude of others. The variety in the shapes of animals and in the arrangements of their different parts is almost endless ; but, with all this variety, all are alike in some things. All have organs to digest their food with, and organs to circulate their blood. All have brains to think with, and nerves to use in finding out about what is around them, and in making their muscles work. The variety in the contrivances in animals is so great, that when one undertakes to study them, he continually finds something new. And one thing is always true of the machinery in animals — it is perfect. It is always exactly fitted to do just what it is made for. No machinery that man ever made is equal to it. Animals are suited in their shapes and arrangements to the way in which they live. Some are made to fly. These have wings ; and the wings exhibit great variety, as you see if you look at the birds and insects that are so busy in the air. Some animals are made to live in the water ; most of these have a broad tail and fins to swim with, but some crawl, as the crab. Some float about, like the hydra, and some lie still, like the oyster. 94 THE VARIETY OF MACHINERY IN ANIMALS. How different animals move. The organs of some animals like those of man. Some animals walk about on the ground. Man is the only an- imal that walks about erect upon two feet. The beasts, you know, are four-footed. The monkey is one of the most singular of beasts : he has neither feet nor hands, but some things which are like both. With these he is more of a climber than a walker. There are many small animals that walk on many feet. And the snakes, without any feet, crawl along the ground. Some animals hop, as the frog and toad. Some go by a long jump, as the grass- hopper, and the troublesome lit- tle flea, which is here represented as magnified by the microscope. Very strong muscles must this animal have to enable it to make such leaps with its long, crook- ed legs. There is great variety in the coverings of animals. But I will tell you about these in another chapter. Some animals are much more like man than others. The bones, and muscles, and nerves, and heart, and brain of some are very much like the same things in our bodies. This is true of many of the four-footed animals. You can therefore know how the parts of the machinery inside of you look by observing the different parts of animals at the meat-market. In a calf’s head you can see how your brain looks. Its lungs, or lights, as they are com- monly called, are very much like yours, and its heart is quite like your heart. And so of other parts. THE VARIETY OF MACHINERY IN ANIMALS. 95 Variety of motion in man. Has more muscles than any other animal. The more an animal moves, the more muscles he has to make his motions with. Man has more variety of motion than any other animal, and so has more muscles. God gives to each ani- mal just the machinery that it needs. Some have machinery that others do not have. Some have very little, while others have a great deal. In our bodies there is a great variety of machinery, for our busy minds want to know and to do very many things. The mind of man does more things with the hand than with any other part of its machinery. I shall therefore now go on to tell you about the hand, and then about those things that, in dif- ferent animals, answer somewhat in place of hands. Questions. — What is said about the variety of machinery in the bodies of animals ? What senses has the oyster ? Why does he have these ? What is said of his mus- cles ? What of his brain and nerves ? Why has not the oyster as much machinery in his body as there is in yours? What machinery has he? Tell all about the hydra. What is said about his brain ? What are his arms made of? In what things are all animals alike ? How does the machinery in animals compare with that made by man ? What are the shapes and machinery of animals suited to ? Tell about animals that fly — those that live in the water — those that walk. What ts said about man ? What is said about the monkey ? Mention some animals that hop — some that make a long jump — those that crawl without feet. What an- imals are much like man, and in what ? Why is there so great a variety of ma- chinery in our bodies ? What part of the machinery do our minds use most ? 96 THE HAND. The hand a set of machinery. It does both coarse and fine work. CHAPTER XXL THE HAND. Man is the only animal that has a hand. The monkey has something like a hand ; but, if you watch him as he takes things, you will see that it is a very awkward and bungling thing com- pared with your hand. The hand is often said to be a wonderful instrument . I would rather say that it is a wonderful set of machinery . An instru- ment or tool is commonly fitted to do only one thing, as a chisel, a spade, a saw, etc. But how many and how different things can be done with the hand ! Let us look at some things that the hand can do. See t;he blacksmith wielding the heavy hammer ; how strongly his hand grasps the handle ! See how it is done. The fingers and thumb are bent by those large muscles that are up in the arm. Now these same fingers, that grasp the hammer so strongly, and do this heavy Avork, can be trained to do work of the lightest and finest kind. They can take hold of the pen and write. They can move the tool of the engraver, making those fine lines that you some- times see. In the machines that man makes there is no such changing from) coarse, heavy work to that which is fine and delicate. A machine that does heavy work does that only, and one that does fine work does that only. No man ever made a machine that would pul] THE HAND. Variety of things done by the hand. The most common things that it docs wonderful. a large rope one moment, and the next pull a fine thread, and do the one just as well as the other. But that wonderful machine, the hand, can do this. It can grasp the rope firmly, and yet can take between its thumb and finger a thread so fine that you can hardly see it. But the difference in the work of the hand is not merely in coarseness and fineness. It can do a great many different kinds of coarse work and a great many different kinds of fine work. The hand works very differently with different things. See how differently it manages a rope, a hammer, a spade, a hoe, a knife and fork, etc. It takes hold of them in different ways to work them. And then, as to fine work, how differently it manages a pen, an engraver’s tool, a thread, a needle, etc. If you watch people as they do different things, you can get some idea of the variety of the work that the hand can perform. See how differently the fingers are continually placed as one is playing on an instrument. You can see very well what a variety of shapes the hand can be put into if you observe a deaf and dumb person talking with his fingers. On the following page is a rep- resentation of the different ways in which the letters are made. The most common things that we do with our hands are really wonderful. Watch one as he is buttoning up his coat : how easily his fingers do it ; and yet it is a wonderful performance. Suppose a man should try to make a machine, shaped like the hand, that would do the same thing, do you think that he would succeed ? It would be very strange if he did. Suppose, however, that, after working a long time, he did really succeed, and that you saw his < G 98 THE HAND. Variety of shapes which the hand takes in the deaf and dumb alphabet. g h i 3 The j is made by raising the little finger as represented, and then moving it as if to make the tail of the letter. The z is made by raising the forefinger, and moving it in a zigzag way. THE HAND. 99 A buttoning machine. The hand an instrument of feeling. machine, with its fingers and thumb, put a button through a but- ton-hole in the same way that you do it with your fingers. Do you think that it could manage buttons of all sizes, large, middle- sized, and small ? No ; it could only button those that are of one size. The different sized buttons would require different ma- chines ; and, besides, a machine that could button up could not unbutton. But your hand is a machine that, besides buttoning and unbuttoning buttons of various sizes, is doing continually a great variety of things that machines can not do. No machine can take up a pen and write, or even move a stick about as your hand can. When some ingenious man makes a machine that can do any one thing like w r hat the hand does, it excites our wonder, and we say, How curious ! how wonderful ! how much like a hand it works ! But the hand is not merely a machine that performs a great many motions ; it is also an instrument with which the mind feels things. And what a delicate instrument it is for this pur- pose! How small are the things that you sometimes feel with the point of the finger ! As you pass it over a smooth surfaoe, the slightest roughness is felt. A great deal of knowledge, as I told you in Chapter XI Y., gets into your mind through the tips of your fingers. Messages are going from them continually by the nerves to the mind in the brain. The blind, I have told you, read with their fingers. They pass them over raised letters, and the nerves of the fingers tell the mind what the letters are, just as the nerves of your eyes are now telling your mind what the letters are in this book. 100 THE HAND. The hand guided by the touch. How it differs from machines made by man. Now, while the hand is performing its different motions as a ma- chine, it is generally very much guided by this sense of touch. If your hand had no feeling in it, it would make awkward busi- ness even in such a simple operation as buttoning ; and it could not do it at all if you did not look on all the time that it was do- ing it. Your eye-nerves would have to take the place of your finger-nerves, as in the reading of the blind the finger-nerves take the place of the eye-nerves. As it is, you need not look at your fingers while they are buttoning, for they are guided by the feel ing that is in them. There was once a woman who lost the use of one arm, and at the same time lost all her feeling in the other. She had a baby to take care of. She could hold it with the arm that had no feel- ing, because she could work the muscles in that arm, but she could not do it without looking at it all the time. If she looked away, the arm would stop holding the baby and let it fall, for it could not feel that it was there. In her case the eye-nerves had to keep watch in place of the arm-nerves that could not feel. You see that the hand is different from the machines that man makes in two things — in the variety of things that it can do, and in the connection which it has with the mind by the nerves. While the mind, by the nerves, makes it do things, it knows by other nerves all the time whether it is doing them right. See, now, what are the parts of this wonderful set of machinery. *There are in the hand and arm thirty bones. There are about fifty muscles, and all these are connected with the brain by nerves. It is by them that the mind makes the muscles perform all the THE HAND. 101 IIow to get an idea of the variety of things which the hand can do. various motions of the hand and fingers, and then there are other nerves that tell the mind what is felt in any part of this machinery. I have mentioned in this chapter a few of the things that are done by the hand, but there is no end to the things that can be done by this set of machinery. You can get some idea of this in two ways — by moving your hands and fingers about in all sorts of ways, and by thinking of as many as you can of the different things that people, in work or in play, do with their hands. And observe in how many more ways the hand is useful than the foot is. The foot has but a few things to do compared with the muh titude of things done by the hand. Questions . — What animal has something like a hand? How does it compare with your hand ? Why would you call the hand a set of machinery rather than an instrument ? What is said about the fingers doing heavy and light work ? Tell about the rope and the thread. What is said about the different kinds of both coarse and fine work that the hand can do ? What is said about playing on an in- strument? What is said of the alphabet of the deaf and dumb? What is said about the common things done continually by the hand ? What is said of the hand as an instrument for feeling ? If your hand had no feeling, what would happen ? Tell about the woman who lost the power of motion in one arm and feeling in the other. In what two' things is the hand different from the machines made by man? What are the parts of the machinery of the hand ? In what two ways can you get an idea of the variety of things that this machinery can do? 102 WHAT ANIMALS USE FOE HANDS. How teeth can serve in place of hands. CHAPTER XXII. WHAT ANIMALS USE FOR HANDS. Though animals do not have hands, they have different parts which they use to do some of the same things that we do witli our hands. I will tell you about some of these in this chapter. You see this dog dragging along a rope which he holds in his mouth. He is making his teeth answer in place of hands. Dogs always do this when they carry things. They can not carry them in any other way. You carry a basket along in your hand, but WIIAT ANIMALS USE FOR HANDS. 103 Cropping grass. Anecdotes of horses. the dog takes it between his teeth, because he has no hand as you have. I have told you, in another chapter, how the cow and the horse crop the grass. They do it, you know, with their front teeth. They take up almost any kind of food — a potato, an apple — with these teeth. These teeth, then, answer for hands to the cow and horse. Their lips answer also the same purpose in many cases. The horse gathers his oats into his mouth with the lips. The lips are for hands to such animals in another respect. They feel things with their lips just as we do with the tips of our fingers. My horse once, in cropping some grass, took hold of some that was so stout and so loose in the earth that he pulled it up by the roots. As he ate it the dirt troubled him. He therefore knocked the grass several times against the fence, holding it firmly in his teeth, and thus got the dirt out, just as people do out of a mat when they strike it against any thing. I once knew a horse that would lift a latch or shove a bolt with his front teeth as readily as you would with your hand. He would get out of the barn- yard in this way. But this was at length prevented by a very simple contrivance. A piece of iron was fixed in such a manner at the end of the bolt that you could not shove the bolt unless you raised the iron at the same time. Probably this puzzled the horse’s brain. Even if he understood it, he could not manage the two things together. I have heard about a horse that would, take hold of a pump-handle with his teeth and pump water into a trough when he wanted to drink. This was in a pasture where there were several horses ; and what is very curious, the other 104 WHAT ANIMALS USE FOR HANDS. Monkeys great climbers. What cats use in place of hands. horses, when they wanted to drink, would, if they found the trough empty, tease this horse that knew how to pump ; they would get around him, and bite and kick him till he would pump some water for them. Monkeys have four things like hands. They are half way be- tween hands and feet. With these they are very skillful at climbing. There are some kinds of monkeys, as the one repre- sented here, that use their tails in climbing as a sort of fifth hand. The cat uses for hands some- times her paws, with their sharp claws, sometimes her teeth, and sometimes both together. She climbs with her claws. She catches things with them — mice, rats, or any thing that you hold out for her to run after. She strikes with her paws, just as angry children and men sometimes do with their hands. When the cat moves her kittens from one place to another, she takes them up with her teeth by the nttpe of the neck. There is no other way in which she can do it. She can not walk on her hind feet and carry them with her fore paws. It seems as if it would hurt a kitten to carry it in the way that she does, but it does not. WHAT ANIMALS USE FOR HANDS. 105 Tho dormouse. The humming-bird’s bill. The bill of a duck. When a squirrel nibbles a nut to make a hole in it, he holds it between his two fore paws like hands. So also does the dormouse, which you see here. The bill of a bird is used as its hand. It gathers with it its food to put into its crop. When you throw corn out to the hens, how fast they pick it up, and send it down into their crops to be well soaked ! The humming-bird has a very long bill, and in it lies a long, slender, and very delicate tongue. As he poises himself in the air before a flower, his wings fluttering so quickly that you can not see them, he runs his bill into the bottom of the flower where the honey is, and puts' his little long tongue into it. The bill of the duck is made in a peculiar way. You know that it gets its food under water in the mud. It can not see, therefore, what it gets. It lias to work altogether by feeling, and it has nerves in its bill for this purpose. Here is a picture of its bill, showing the nerves branching out on it. You see, too, a row of pointed things all around the edge. They look like teeth, but they are not teeth. They are used by the duck in finding its food. 106 WHAT ANIMALS USE FOR HANDS. The power of the elephant’s trunk and the variety of thirgs it can do. It manages in this way : it thrusts its bill down, and as it takes it up it is full of mud. Now mixed with the mud are things which the duck lives on. The nerves tell the duck what is good, and it lets all the rest go out between the prickles. It is a sort of sift- ing operation, the nerves in the sieve taking good care that noth- ing good shall pass out. One of the most remarkable things used in place of a hand is the trunk of the elephant. The variety of uses to which the ele- phant puts this organ is very wonderful. It can strike very heavy blows with it. It can wrench off branches of trees, or even pull up trees by the roots, by winding its trunk around them to grasp them, as you see it is doing here. It is its arm with which it WHAT ANIMALS USE FOR HANDS. 107 The elephant’s trunk can do little things as well as great. carries its young. It is amusing to see an old elephant carefully wind its trunk around a new-born elephant, and carry it gently along. But the elephant can also do some very little things with his trunk. You see in this picture that there is a sort of finger at the very end of the trunk. It is a very nimble finger, and with it this monstrous animal can do a great variety of little things. He will take with it little bits of bread, and other kinds of food that you hand to him, and put them into his mouth. He will take up a piece of money from the ground as easi- ly as you can with your fingers. It is with this finger, too, that he feels of things just as you do with your fingers. I once saw an elephant take a whip with this fingered end of his trunk, and use it as handily as a teamster, very much to the amusement of the spectators. The elephant can reach a considerable distance with his trunk. And this is necessary, because he has so very short a neck. He could not get at his food without his long trunk. Observe, too, how he can turn this trunk about in every direction, and twist it about in every way. It is really a wonderful piece of machinery. Cuvier, a great French anatomist, says that there are over thirty thousand little muscles in it. All this army of muscles receive their orders by nerves from the mind in the brain, and how well they obey them ! You see that there are two holes in the end of the trunk. Into these he can suck water, and thus fill his trunk with it. Then he 108 WIIAT ANIMALS USE FOR HANDS. The elephant and the tailor. can turn the end of his trunk into his mouth and let the water run down his throat. But sometimes he uses the water in his trunk in another way ; he blows it out through his trunk with great force. He does this when he wants to wash himself, directing his trunk in such a way that the water will pour over him. He some- times blows the water out in play, for even such great animals have sports like children. Sometimes, too, he blows the water on people that he does not like. You perhaps have read the story of the tailor who pricked the trunk of an elephant with his needle. The elephant, as he was passing, put his trunk into the shop win- dow, hoping that the tailor would give him something to eat. He was angry at being pricked, and was determined to make the man sorry for doing such an unkind act. As his keeper led him back past the same window, he poured upon the tailor his trunk full of dirty water, which he had taken from a puddle for this purpose. Questions . — What is said about the dog ? What answer for hands to the cow and the horse ? Tell the anecdotes about horses. What does the cat use for hands, and how ? What is said about the squirrel and dormouse ? What is the bird’s hand ? Tell about feeding the hens. Tell about the bill of the duck. What is told of the humming-bird ? Mention some of the variety of uses to which the elephant can put his trunk. What is said about the finger on the end of it ? Why does the el- ephant need so long a trunk ? What is said about the muscles in it ? How does the elephant drink? How does he wash himself? Tell about the tailor. TIIE TOOLS OF ANIMALS. 109 Man alone makes tools. Animals have some kinds of tools ready madn. CHAPTER XXIIL THE TOOLS OF ANIMALS. Man is the only animal that makes tools to use. God has given him a mind that can contrive tools, and he has also given him hands by which he can use them. But he has given no such mind to other animals, and therefore he has not given them hands. They do not know enough to make tools, and so hands are not needed by them. But, though other animals do not make tools, they have tools which they use. God has given them ready made, as we may say, such tools as they need. Let us look, then, at some of the tools that we find in different animals. You see a man in the stern or hinder end of a small boat. He is scull- ing, as it is called. He is making the boat go by working the oar to the one side and the other. The oar is the tool or instrument by which he does it. Now a fish has an instru- ment like this, by which 110 THE TOOLS OP ANIMALS. The tail of a fish a sculling-oar. The drill of the woodpecker. he goes through the water. His tail is like the sculling-oar that man has contrived, and which he uses with his hands. If you watch the fish as he goes through the water, you will see that he moves it to one side and the other as the man does his oar ; and while he goes ahead by means of his tail, he uses his fins mostly as balancers to guide his motion. He moves them rather gently except when he wants to change his course quickly. When he is moving along fast, and wants to stop, he makes his fins stand out straight on each side. This is just as rowers in a boat use their oars when they want to stop the boat. You see a man drilling a hole in a rock, and you hear the sound of the tool as it goes click, click, all the while. The woodpecker has a drill that works in the same way. With his bill he drills holes in the trees, and you hear the sound of his tool as you do that of the tool of the rock-blaster. It is a sort of knocking sound repeated many times very quickly. What do you think that the woodpecker drills holes for? It is to get at worms and insects, which he eats. These are in the bark and wood of dead trunks and branches of trees. The wood- pecker knows this, and so drills to find thorn. He does not drill into live bark and wood, for he knows that there are generally no worms or insects there. But the woodpecker’s instrument is something more than a drill. It is a drill with another instrument inside of it. This instrument is for pulling out the insect or worm that he finds in drilling. It is shown in the following figure. It is a very long, straight tongue, and ends in a bony thorn. This is, as you see, THE TOOLS OP ANIMALS. Ill Tongue and claws of the woodpecker. Digging tools of the elephant, the hen, and the pig. armed with sharp teeth pointing backward, like ^ the barbs of a fish-hook. Here are, then, two in- struments or tools to- gether. And the way that the woodpecker manages them is this : while he is drilling, the two parts of the bill are closed together, making a good wedge-pointed drill, and at the same time a snug case for the insect-catcher. As soon as he comes to an insect he opens the drill, and pushes the barbed end of his long tongue into the insect, and draws him into his mouth. As the woodpecker has to strike so hard in drilling, the bones of his skull are made very heavy and strong. If this were not so, his drilling would jar his brain too much. And another thing is to be observed: while he is drilling he needs to stand very firmly. He must hold on tightly to the tree, or lie will slip as soon as he begins to drill. He has, therefore, such claws as you see here to hold on with. Some animals have tools to dig with. The elephant, you know, has long, strong tusks. These he uses in digging up roots of dif- ferent kinds from the ground to eat. The hen digs in a small way with the claws of her feet, to find grains and other kinds of food that happen to be mingled with the earth. The pig can dig with its snout. It does not have much. use for this when shut up in its pen ; but let it out, and see how it will root, as we say. It 112 THE TOOLS OF ANIMALS. The mole’s plowing and digging tool Ilis habitation. does this to find things in the ground that it can eat. When the pig runs wild, it roots to get acorns and other things that be- come mixed up with the earth. The mole has a similar contrivance to work in the earth with. This animal also has heavy claws with which it plows and digs. Here is a fig- ure showing the bones of one of its fore paws. They are very heavy and strong, and are worked by large muscles. The claws on its fingers, you see, are very powerful. The mole does great execution with this digging and plowing machine in mak- ing his tunnels and galleries in the ground. The mole’s habitation is a singular affair. It consists of a large circular room, with several galleries and passages. He makes all this in this way. He first heaps a round hill or mound, pressing the earth to make it very solid and firm ; he then digs out his round room, where he lives, and the passages. You can under- stand how he arranges these by the figure. You can see that there are two circular galleries, one above the other, and that these are connected together by five passages. The circular room is connected with the upper gallery by three passages. It also, you see, has a deep passage out from it at the bottom, which opens into a passage that goes out from the lower gallery ; this passage, and another like it on the other side, lead out into the open air. I suppose that the use THE TOOLS OF ANIMALS. 113 How the woodchuck digs. IIow beavers build their cabins. of all these winding passages is to enable the mole to keep out of the way of those who want to catch it. The marmot, or woodchuck, as he is commonly called, is a great digger. He digs his hole where he lives in this way. He loosens the dirt with his fore paws, using his teeth also when the earth is very hard, or where any roots happen to be in the way. He push- es back the dirt as he loosens it. When he gets a considerable heap, what do you think that he does with it ? He shovels it out with his hinder feet, for they are so shaped that he can use them as shovels. They have a strong skin between the toes, so that when the toes are spread out the feet answer very well to shovel dirt with. Beavers are very singular animals. They do not live alone, but many of them live together. They live in a sort of cabin, which they build with branch- es of trees and mud, the mud answering for mortar. In gath- ering the branches they often gnaw them off with their sharp and powerful teeth. They are great diggers. They dig up the earth with their paws to use in building their cabin. It is said that they use their flat tails somewhat as masons do their trowels, spatting and smoothing the coating of mud as they put it on. The tail, which you see is very stout, answers another pur- 2 H 114 THE TOOLS OP ANIMALS. The arrangement of the cabins and dams of beavers. pose. As the beaver builds the wall of the cabin, when it gets rather high he props himself up on his tail as he works. The beavers build their cabin close to a stream of water, and their entrance to it is below, so that they have to go down under water to get to it ; and a dam is built to keep the water over this entrance of the proper height. If it were not for this, the door to the cabin might get closed up with ice if the water should get low in the stream during the winter. This dam the beavers build of branches of trees, and mud, and stones. The stones are used to make the branches stay down. In the cabin there are two rooms : in the upper one they live, and in the lower one they stow their food. This is the arrangement of these animals for the winter. In the summer they do not live together in companies, but each one makes a burrow for itself. Every autumn they come togeth- er, and unite in building their dams and cabins. Questions . — Why does man make tools ? Why do not other animals make them ? Do they have tools ? How is the swimming of a fish like sculling ? What does the fish do with his fins ? What is said about the bill of the woodpecker ? What does he drill for ? Tell about his tongue. What is said about the bones of his head ? What about his claws ? What is said about the digging of the elephant— of the hen — of the pig? How does the mole dig? What is said about his fore paws? Describe the arrangement of the mole’s habitation. How does the wood- chuck dig? How does he shovel away the dirt that he digs ? Tell about the bea- vers. In what two ways do they use their tails ? What is the arrangement ot tp* cabin? What is the dam for ? MORE ABOUT THE TOOLS OF ANIMALS. 115 The saw-fly. The bee that cuts leaves so curiously. CHAPTER XXIV. MORE ABOUT THE TOOLS OF ANIMALS. Insects have various tools or instruments. There is a fly call- ed the saw-fly, because it really has a saw. It is a very nice one, much nicer than any saw that man ever made. The fly uses the saw to make a place to put its eggs, where they will be secure. And what is very curious, it has a sort of glue with which it fast- ens the eggs in their place. There are some insects that have cutting instruments, v/hich will cut as well as you can with scissors, if not better. There is a bee that is remarkable in this respect. It has also a boring tool. Its nest is commonly in old, half-decayed wood. It clears out a space in it with its boring instrument ; it then sets itself to work with its cutting instrument to cut out pieces of leaves to line t tig nest and make the cells in it. These are cut of different shapes, as they are needed, as you may see in the next engraving. Below the leaves you see the nest represented. It is opened by taking off some of the wood, and there you see the lining of leaves. Great pains is taken by the bees in getting each piece of leaf of the right shape to fit well, and the pieces are very nicely fastened together.* There are some animals that have machinery for making things. * A more full account of the operations of this little animal you can find in a book published by Harper and Brothers, entitled Natural History, by Uncle Philip, which I recommend to my young readers as a very interesting book about animals. 116 MORE ABOUT THE TOOLS OF ANIMALS. The spinning machinery of the silk- worm and the spider. All the silk that is used in the world is made by worms. The silk- worm has a regular set of machinery for spinning silk. It winds it up as it spins it. Then man unwinds it, and makes a great variety of beautiful fabrics with this silk thread. The spinning machinery of the spider is much finer than that of the silk-worm. The thread which he spins is made up of a multitude of threads, each one of these coming out from an exceed- ingly small hole in the spider’s body. You know that there is a large number of fibres or threads in a rope. So it is with the spi- der’s rope, for his thread that you see, small as it is, is a rope to him. It is a rope that he walks on like a rope-dancer; and you may sometimes see him swinging upon it. Sometimes, too, he lets himself down from some height, spinning the rope that holds him as he goes down. When he does this, his spinning machine must work very briskly. The wasp has a paper factory in him. He makes his paper out of fibres of wood, which he picks off, I suppose, with his teeth, and gathers them into a bundle. He makes this into a soft pulp in MORE ABOUT THE TOOLS OF ANIMALS. 117 Paper-making of the wasp. Teeth. Pumps of some animals. some way ; then, from this, he makes the paper with which he builds his nest. It is very much, you know, like the common brown paper that man makes. The wasps work in companies, and though each one can make but little paper, they all together make their nest in a very little time. The pulp from which they make their paper is very much like the pulp from which man makes paper, and which you may see any time in the large tubs or vats of a paper factory. This pulp is generally made from rags ground up fine, but lately wood has been much used. Perhaps the hint was taken from the wasps, who were the earliest paper-makers in the world. Animals can not use knives and forks, as we do, in dividing up their food. They therefore have instruments given them which do this very well. Those long, sharp teeth that dogs, cats, tigers, etc., have, answer to tear to pieces the flesh they eat, as thoroughly as we can cut it up. We do not need 'such teeth, because with instruments contrived by man’s mind for his hands to use we cut up the food sufficiently. I have told you that the elephant can draw up water into his trunk. His trunk is therefore like the tube with which we suck up water or any liquid. And it is like a pump too, for, as I shall show you in Part Third, water is raised in the pump just as it is in a tube when we suck through it. It is with a pump something like the elephant’s that many insects get the honey from the flow- ers. This pump is called a proboscis. It is with such an instru- ment that the musquito sucks up your blood. At the end of his pump he has something with which he pierces a hole in your skin. 118 MORE ABOUT THE TOOLS OF ANIMALS. The proboscis in some insects. The proboscis of the humming-bii-d. and then he pumps your blood up into his stomach. In some in- sects the proboscis is very long, as you see here. This is hol- low, and with it the insect sucks up the honey from very deep flowers, without being obliged to go to the bottom of them. The proboscis is commonly coiled up when it is not in use. Here is the proboscis of a butterfly coiled up. The two long things above it are feelers. The tongue of the humming-bird is really a proboscis, and a very curious one it is too. It has two tubes alongside of each other, like the two barrels of a double-barreled gun. At the tip of the tongue these tubes are a little separated, and their ends are shaped like spoons. The honey is spooned up, as we may say, and then it is drawn into the mouth through the long tubes of the tongue. But the bird uses its tongue in another way. It catches insects with it, for it lives on these as well as on honey. It does it in this way : the two MORE ABOUT THE TOOLS OP ANIMALS. 119 Cat’s tongue a curry-comb. How the heron catches fish. spoons grasp the insect like a pair of tongs, and the tongue, bend- ing, puts it into the bird’s mouth. The tongue, then, of the hum- ming-bird is not merely one instrument, but it contains several instruments together — two pumps, two spoons, and a pair of tongs. The tongue of a cat is a singular instrument. It is her curry- comb. For this purpose it is rough, as you will find if you feel it. When she cleans herself so industriously, she gets off the dirt and smooths her coat just as the hostler cleans and smooths the horse’s coat with the curry-comb. Her head she can not reach with her tongue, and so she has to make her fore paws answer the purpose instead. There are some birds that live on fishes. They have instru- ments, therefore, purposely for catching them. The heron is a bird of this kind. He manages in this way: when the light is dim, either at dawn or when there is moonlight, it is his time for going a fishing. He will stand, as you see him here, in shallow water, so stiff and so still that he might be mistaken for a stump of a tree or something else. He is looking steadily and patiently down into the water, and the moment a fish comes along, down goes his sharp bill, and off he 120 MORE ABOUT THE TOOLS OF ANIMALS. The tailor-bird. The wingless bird. flies to his nest with his prey. The plumes of this singular bird are beautiful, and are very highly prized as ornaments. There is one bird that lives chiefly on oysters. It has a bill, therefore, with which it can open an oyster-shell as skillfully as an cysterman can with his knife. Some birds can sew very well with their beaks and feet. There is one bird that sews so well that it is called the tailor bird. Here is its nest hid in leaves which it has sewed tog<^her. It does this with thread which it makes itself. It gets cotton from the cotton-plant, and with its long, delicate bill and little feet, spins it into a thread. It then pierces the holes through the leaves with its bill, and, passing the thread through the holes, sews them together. I believe that in getting the thread through the holes it uses both its bill and its feet. Here is a very strange-looking bird. It has no wings. It has a very long bill, which it uses in gathering its food, which consists MORE ABOUT THE TOOLS OF ANIMALS. 121 The fish that shoots insects with a squirt-gun. of snails, insects, and worms. He uses his bill in another way. lie often, in resting, places the tip of his bill on the ground, and thus makes the same use of his bill that an old man does of his cane when he stands leaning upon it. There is a fish that has a singular instrument. It is a squirt- gun for shooting insects. It can shoot them not only when they are still, but when they are flying. It watches them as they are flying over the water, and hits one of them, whenever it can get a chance, with a fine stream of water from its little gun. The insect, stunned with the blow, falls into the water, and the fish eats it. I could give you a great many more examples of the different tools that we find in animals, but these are sufficient. You can observe other examples yourselves as you look at different animals. Questions . — What is said about the saw-fly ? Tell about the boring and cutting instruments of a certain kind of bee. What is said about silk-worms ? What about spiders ? What about wasps ? Why do some animals have such long, sharp teeth ? What kind of machine is an elephant’s trunk ? What is the proboscis of an insect ? Tell about the tongue of the humming-bird. How many instruments are there to- gether in his tongue ? What is said about the cat’s tongue ? Tell about the heron. Tell about the bird that lives on oysters. What is told about the tailor-bird ? Tell about the bird that has no wings. Tell about the fish that shoots insects with water. 122 INSTRUMENTS OF DEFENSE AND ATTACK. Fighting instruments of animals. Why man has none of them. CHAPTER XXV. INSTRUMENTS OF DEFENSE AND ATTACK. Animals have various instruments for defending themselves. Some have claws, some horns, some hoofs, some spurs and beaks, some powerful teeth, and some stings. These they use to defend themselves when attacked. But man has none of these things. Why is this ? It is be- cause, as I have told you about tools, with his mind he can con- trive instruments of defense, and with his hands he can use them. If men could not contrive and use such things as spears, and swords, and guns, they would stand a poor chance with some of the animals if obliged to contend with them. A lion or tiger, you know, could tear the stoutest man in pieces if he had nothing in his hands to defend himself. It would be well if men would use the fighting instruments which they make only for defending themselves. But they often use them in attacking others, just as beasts do their weapons, and sometimes they even use their hands, and teeth, and nails in the same way that beasts do. Hands were made for useful work and innocent play ; but they are often used to strike with. Teeth are given to us to eat with ; but children, and even men sometimes, bite with them like an angry beast. Nails are given us for vari- ous useful purposes, but I have known children to use them in fighting* as beasts do their claws and spurs. INSTRUMENTS OP DEFENSE AND ATTACK. 123 Claw and beak of a cruel bird. The vulture and the lamb. The fighting instruments of some birds are very powerful. Here are a claw and a beak of a very cruel bird. How fast this claw would hold the victim, and how would this beak tear it in pieces ! Very different are they from the slender claws and the light beak of such birds as the canary. Here is a very rapacious bird, the vulture. He is on a rock, and has under his feet a lamb which he found in the valley be- low. It had perhaps wandered from the flock, and, as it was feeding, not thinking of danger, the vulture espied it. Swiftly diving down, he caught it with his strong claws and brought it up here. You see what a beak he has to tear the lamb in pieces, that he may devour it. 124 INSTRUMENTS OF DEFENSE AND ATTACK. The bill of the toucan. How it trims its tail. The toucan, which you see here, has a larger bill than most oth- er birds. It uses it in crushing and tearing its food, which consists of fruits, mice, and small birds. You see that its edges are toothed somewhat like a saw, adapting it to tear in pieces the little animals which this bird feeds on. But it can use its bill also for another pur- pose. It is a powerful instrument of defense in fighting off the animals that attack it. The tou- can makes its nest in a hole of a tree, which it digs out with its bill, if it does not readily find one already made ; and there it sits, keeping off all intruders with its big beak. The mischievous monkeys are its worst enemies ; but, if they get a blow from that beak, they are very careful to keep out of the way of it afterward. When the toucan sleeps, it manages to cover up this large bill with its feathers, and so it looks as if it was nothing but a great ball of feathers. There is one curious use which it makes of its bill : it uses it to trim its tail, cutting its feathers as precisely as a pair of scissors would. It takes great care in doing this, evi- INSTRUMENTS OF DEFENSE AND ATTACK. 125 The cat’s paw and its cushions. Horned animals. dently thinking that it is important to its beauty. It waits till its tail is full grown before it begins to trim it. The claws of the cat hold the rat very fast, while her long, sharp teeth tear its flesh, and pull even its bones apart. If you see a cat do this, you will get some idea of the way in which a lion or tiger tears in pieces any animal. As your cat lies quietly purring in your lap, look at her paws. The claws are all concealed, and the paw, with its cushions, seems a very gentle, peaceable thing; but wake her up and let her play with a string, and as she tries to catch it with her paw, the claws now thrust out make it look like a powerful weapon, as it really is in the eyes of rats and mice. There are muscles that work those claws when the cat’s mind tells them to do it. When the claws are not thrust out these muscles are quiet, but they are ever ready to act when a message comes to tligm from the brain. Did you ever think what the use is of those springy cushions in the cat’s foot ? They are to keep her from being jarred when she jumps down from a considerable height, as she often does. Other animals that jump have them. There is another use for these cush- ions. They are of assistance to animals in catching their prey. If the cat had hard, horny feet, as she went pattering around the rats and mice would take the alarm and get out of the way. Some animals have horns which they use in attack and de- fense, and very powerful weapons they are in some cases. Animals that have them often defend themselves successfully against the at- tacks of lions, tigers, etc., that are so powerful with their teeth and claws. They gore with them. They can toss up quite a large 126 INSTRUMENTS OF DEFENSE AND ATTACK. The horns of the kudu. The sword-fish. animal into the air with them. In this animal (called the koodoo) they are nearly three feet long. You see that they have a beau- tiful spiral shape ; in- deed, the whole animal is very handsome. It lives in South Africa, in woods at the side of rivers. You might suppose that it would be rather difficult to get about among the trees and bushes with sitfch long horns; but the koodoo manages to do this very well by throwing his head back and letting his horns rest on his shoulders. Here is a draw- ing of a sword- fish. Its sword is made of bone, and it is so very strong that it has been known to be run through the 127 INSTRUMENTS OF DEFENSE AND ATTACK. The saw-fish. The porcupine. - — ; bottom of a ship. In the British Museum there is a piece of the bottom of a ship with one of these swords run through it, and broken short off. The fish ipust have died at once, for such a blow must have dashed his brains out, as we say. This sword must be a powerful weapon of defense or attack in the fights of this fish with other animals. Here is a fish that has a saw instead of a sword. The teeth, you see, are on both sides of the saw. This fish is very large, and uses this weapon with great effect in its fights with whales and other mon- sters of the deep. It sometimes very foolishly pushes its saw into the bottom of a ship, as the sword-fish does his sword. There are some an- imals that have very singular instruments of defense. The por- cupine is one. It is covered with two kinds of quills. Those of one kind are long, slen- der, and curved. The 128 INSTRUMENTS OF DEFENSE AND ATTACK. What the porcupine does with his quills. The ink-bag of the cuttle-fish. others are short, straight, very stout, and have a sharp point. Whenever the porcupine is chased by any animal, and finds that he can not escape by running, he stops and bristles up all his quills, as you see in the previous engraving. He then backs, so that the short, sharp quills may stick into the animal that pursues him. It has been said that he shoots his quills at any one that attacks him. But this is not so. The error came from the fact, that if any of the quills happen to be a little loose, they fall out or stick into the flesh of his adversary. The cuttle-fish has a curious way of escaping from those fishes that attack him. He is a strangely-shaped animal, as you see. He has eight long arms, and the little spots that you see on these are suckers, with which he can stick to a rock, or can hold tightly any fish or shell that he catches. This queer- looking animal has in- side of him a bag filled with a dark fluid like ink. This he uses as a means of defense in this way : if he is chased by a fish larger than he is, he empties his ink-bag in the water, and thus makes such a cloud that it blinds his pursuer, and then the cuttle-fish very easily gets out of the way. INSTRUMENTS OF DEFENSE AND ATTACK, 12 £> The torpedo. The electric cel. This singularly-formed fish, the torpedo, has two electrical bat- teries — that is, ma- chines for making electricity or light- ning; and it can give a shock when it pleases. If the fish is a large one, it can give a shock powerful enough to knock a man down. It can disable, of course, almost any fish that attempts to fight with him, and it probably uses its battery also to over- come the animals that it devours. Here is an eel, calk ed the electrical eel, which has the same power, and uses it for the same purposes. A sailor was once knock- ed down by a shock from one of these eels, and it was some time before he recovered his senses. 1 he different kinds of turtles, while they have no great means * I 130 INSTRUMENTS OF DEFENSE AND ATTACK. The armor of turtles. of attack, have most extraordinary means of defense. They have a complete suit of thick, bony armor. Most kinds of turtles can draw in their heads and limbs out of sight, and some can shut up their armor as tight as a box, and so be secure against almost any attack. This is a picture of the green turtle, which sometimes grows so large as to weigh as much as three or four men. It is found in most of the islands of the East and West Indies. Its flesh is considered a great luxury. The beautiful tortoise-shell, from which combs are made, is obtained from this armor of some kinds of turtles. Questions . — What are some of the instruments of defense and attack that animals have ? Why has man none of these ? What is the use which men ought to make of the weapons which they contrive ? How are hands, teeth, and nails often im- properly used? What are the fighting instruments of birds? Tell about the vul- ture. Tell the different uses of the large bill of the toucan. What are the weap- ons of the cat ? What is said about the muscles of her claws ? Of what use are the cushions on her feet ? Tell about the koodoo. Tell about the sword-fish and about the saw-fish. What is said about the porcupine? What about the cuttle-fish? What about the torpedo and the electrical eel? What about the turtles? WINGS. 131 Bones of a bird’s wing like the bones of the arm and hand. Why wings are so large. CHAPTER XXVI. WINGS. Birds walk upon two legs as we do ; but, instead of such hands as we have, they have hands made for the purpose of lifting them up in the air. The bones in a bird’s wing are very much like the bones in our arms and hands; but they make a frame-work for the feathers of the wing to spread out from. The bones that go out almost to the very end of the wing are like the bones of our fingers, only they are much longer. A bird’s wing, when it is stretched out, is a very large thing. It needs to be large to do its work well. A bird could not fly with small wings. You know that by trying very hard you jump up into the air a very little way. But see, the bird goes up very easily as high as it pleases, and does not seem to be tired. This is because its wings spread out so broadly. The reason that birds need such large wings is this. As the bird rises by pressing upon the air, it must press on a good deal of air to do this. If it pressed upon only a little air it could not rise at all, because the air gets out of the way so easily when it is pressed upon. Sivimming is flying in the water ; and, as water when pressed does not get out of the way as easily as air does, the tail and fins, with which fishes swim, do not need to be as large as the wings of birds. For fhe same reason, hands and feet answer very well for us to swim with, though Ave can not fly with them. I shall tell you more particularly about this in Part Third. 132 WINGS. Wings of the condor. Muscles that work the wings of birds. Here is a very large bird, the condor. To lift such a heavy body as lie has up into the air must require very large wings, and you see that he lias them. Now, to work such broad wings, the bird has very stout mus- cles. You know how the breast of a bird stands out. You see it here in the condor. This is because the muscles with which it works its wings are there. You can sec that this is the reason when a bird is cooked. The meat, you know, is very thick on the breast-bone — thicker than in any other part of the body. If we had as large muscles on our breast-bones we should look very strange. But we do not need such large muscles to work our arms as birds do to work their wings. A man could not fly if he had wings fixed on to his arms. It has been tried. I knew a man once to make something like wings for himself. After he had made them, he went up on to the roof of a shed to try them. He jumped off and flapped his wings, but WINGS. 133 Why men can not fly. Short wings. The ostrich. down lie came about as soon as if lie bad no wings, and he was so much bruised that he was not disposed to try the experiment again. Now why could he not fly ? It was not for want of wings. There the wings were, and he had made them right, for he had shaped them like the wings of birds. They were large enough and light enough ; the difficulty was, that the muscles of his arms were not strong enough to work them well. They were arm- muscles and not wing-mus- cles. A man can not be like a bird merely by hav- ing wings. He must have a bird’s flying muscles, or he can not fly. Different birds have wings of different sizes. Those that fly very far and swiftly have the largest wings. The wings of the hen are not large enough to carry her far up into the air. The most that she can do is to fly over a very high fence ; and if her wings are partly cut oft', or cropped, as it is called, she can not even do that. There are some birds that do not use their wings in flying. 134 WINGS. The beautiful motions of birds. The swallow. The humming-biTd. The ostrich, represented on the previous page, is a great runner. He can not fly, but liis wings help him some in running. In what way the wings act in raising birds and carrying them along I will explain to you in Part Third, when I come to tell you about the air. How beautiful are the motions of many of the birds as they fly in the air ! How easily and gracefully their wings work ! See that bird as it goes up and up ; and now see it as it makes a turn, and comes down so swiftly on its outstretched wings, taking a beautiful sweep off at a distance; and then up it goes again to come down, in the same way that boys do when they travel up a long hill to slide down so swiftly on their sleds. The swallow, as he has this fine sport, is, at the same time, getting his living. As he skims along close to the ground or the water, as represented here, quick as thought he catches any un- lucky fly that happens to be in his way. Especially beautiful are the motions of the hum- ming-bird. See him as he stops before some flower fluttering on his wings, or as he darts with them from one flower to another. The muscles of his wings are very nimble workmen. Our muscles can make no motions as quick as these. Did you ever examine a feather from a bird’s wing to see what WINGrS. 135 The structure of feathers. The delicacy of a bat’s wing. a curiously-made thing it is ? The quill part of it is very strong, but, at the same time, light. The plume or feather part is quite strong also. It is made up of a great many very thin and deli- cate. flat leaves, as we may call them, which are locked together curiously by fine teeth on their edges. If you separate them they soon come together again, and are locked as fast as ever. You can see the teeth by which they hold on to each other very well with a common microscope. No wonder that the bat can fly so swiftly with such very broad and light wings as he has. Did you ever observe how a bat’s wing is made ? It is a very curious and really beautiful thing. It is an exceedingly fine, thin skin, on a frame- work of long, slen- der bones. These are to it what sticks of whalebone are to an umbrella ; and the wings can be folded up somewhat as an umbrella is. This is done whenever . tho bat is not flying. When it is on the ground it is very awkward in its movements. It can not get a start to fly, and so it pushes itself along with its hind feet, at the same time pulling by the hooks in its wings, which it puts forward, first one and then the other, hooking them into the ground. It never likes to get upon the 130 WINGS. The vampire bat. Locust's wing. Wing of the katydid. ground, and it takes its rest always, as you sec represented on the previous page, by hanging itself up by the two hooks in its wings. Here is a picture of the vampire bat, a na- tive of South America, that lives by sucking the blood of animals when they are asleep. Nothing is more del- icate than the wings of insects. They are like gauze ; but they have a frame-work that makes them quite firm, just as leaves are firm -from the ribs that are in them. Here is a drawing of the wing of a locust. But you can get no idea of the beauty of in- sects’ wings from such drawings. You must examine the wings themselves. Even the wing of a common fly is very beautiful, so delicate is its structure. The wing of the katydid, as it is called, is peculiarly beauti- ful. Here it is. You see that it is very delicate. Its color is a light green. You see that rather thick three-cornered ridge at that part of the WINGS. 137 How the katydid makes its noise. How you can stop it. wing which joins the body. There is a similar ridge on the wing of the other side. In the space within this ridge there is a thin but strong membrane or skin, so that it makes a kind of drum- head. It is the rubbing together of these two drum-heads on the wings that makes the noise. It is a queer sound. There is no music in it, but the katydids seem to enjoy making it. The katydid commonly makes three rubs at a time with its drum-heads. It sounds somewhat as if it said Katy-did, and from this comes its name. Sometimes there are only two rubs, and then you can fancy that it says She did or She didn’t. The katydids, you know, are all quiet in the daytime, but when even- ing comes they are very noisy. I have often been amused to hear them as they begin just at dusk. One will begin, and per- haps say its Katy- did several times ; then another, on a neigh- boring tree, will reply ; and after a little time the whole tribe will be at work. Each one appears to rest upon it after each rubbing, and so it seems as if they answered each other from one tree and another. It is curious that you can at once stop the noise of this insect by striking the trunk of the tree on which he is with your hand. Questions . — What are the bones in a bird’s wing like ? What is said about the size of birds’ wings ? What about the muscles that work them ? Why can not a man fly if he makes wings for himself? What birds have the largest wings ? What is said about the hen ? What about the ostrich ? What is said about the motions of birds in flying ? What is said of the swallow ? What of the humming-bird ? Tell about the parts of a feather from a bird’s wing. What is said about the bat’s wings? What about its motions on the ground? How does it rest? What in said about the wings of insects ? How does the katydid make its noise ? 138 COVERINGS OF ANIMALS. The skin of man. Why it is different from the covering of animals. CHAPTER XXVII. COVERINGS OF ANIMALS. The skin of man is liis covering. It covers up like a case all the machinery that I have told you is in his body — the bones, the muscles, the nerves, the arteries, the veins, etc. It keeps them from being injured. Besides this, how strange we should look* if there were no skin to cover up these parts from view. The skin fits very nicely all parts of the body. On the hand it is like a glove. See how well it fits. But observe that there are some places where it is quite loose and full of wrinkles. It is so between the thumb and forefinger, and around the joints of the fingers. In these places it would not do to have it fit tight, be- cause if it did you could not move your thumb and fingers as freely as you do. But the covering of man’s body is different from that of other animals. It is, for the most part, bare skin, while most animals have either hair, or feathers, or scales, or hard plates like armor, or shells. Why is it that man has a covering that protects him so much less than animals generally are protected by their cover- ings ? It is because he knows how to make such a covering as he needs to put on over his skin. He can suit this to the degree of heat or cold. But animals know nothing about this. No one ever saw an animal make clothes and put them on. The Crea- tor has given to each animal such covering or clothes as it needs, ready-made. Let us look at this a little. COVERINGS OF ANIMALS. 139 Fur and hair. Blanketing the horse The fur of the cat. Feathers. Animals in very cold climates need a very warm covering. They therefore have a thick fur. But animals that live in warm countries havQ rather thin hair instead of fur. The elephant has very little hair, and it is only with the greatest care that he can be made to live through our cold winters. The same is true of the monkey. If these animals had a good covering of fur on their skins, the cold would not affect them in this way. The hair of the horse is rather thin* It is not like fur ; and if the horse’s master is kind, he is very careful to put a good blank- et on him whenever the cold makes it necessary. If he did not, the horse would get chilled and take cold. The horse is not a native of cold countries, but of such warm countries as South America and Arabia. There horses run wild, and are always in large companies or herds. You know how thick the fur is on the cat. You can see how fine it is, and how thickly the hairs stand together, if you blow on it so as to separate the hairs. With this warm coat on her, she does not feel the cold much. You see her often in cold weather out-of-doors, with her feet gathered up under her to keep them warm. The monkey, with his thin hair, could not do so. He has to be kept in a warm place in the winter. The covering of birds, while it is such as to keep them warm, is very light. If it were not so, they could not fly as well as they do. Feathers are so light, that, when we wish to speak of any thing as being very light, we say that it is as light as a feather. The downy feathers on the breast of birds are especially light. The feathers of the wings are different. They are made strong 140 COVERINGS OF ANIMALS. The oily feathers of the duck. Why fishes have scales, and why they are oily. for the work of flying, and at the same time they are quite light. How this is done I have told you in the chapter before this. Birds that go much into the water have an oil about their feath- ers which keeps them from being soaked ; for this reason, a duck, when it comes out of the water, is almost as dry as before it went in. But if a hen should go into the water in the same way, she would be wet through her feathers to her skin. She was not made » to go into the water, and so has neither the oily feathers nor the webbed feet which are given to the duck. Why is it that fishes have scales ? It is because they need a smooth covering in ordej: to get along easily in the water. A cov- ering which is rough, or which would soak in water, would be bad tions of the fish. If the same covering were all in one, instead of being made up of many scales, it could not bend as easily as it does now in turning its course in the water. The scales are kept oiled, and this helps the fish to glide along swiftly. It is this that makes the fish so slippery that it is difficult to hold it in its struggles when it is first taken out of the water. I have told you, in another chapter, about the coverings of such for them. The scales, you know, lap over one upon another, as you see here in the herring. They thus make quito a firm coat of mail, and at the same time do not hinder the bending mo- COVERINGS OF ANIMALS. 141 How the hermit-crab guards his naked tail. animals as lobsters and crabs. There is one kind of crab, called the hermit-crab, that has no covering over his tail as lie has over the other parts of his body. It is therefore very liable to be in- jured unless it is guarded in some way. And how do you think he guards it? He just puts it into some shell that he finds, as you see here, and then goes about, dragging it after him. As he grows the tail becomes too large for the shell, and as soon as he feels the shell begin- ning to pinch, he pulls his tail out and goes in search of another shell. It is amusing to see him try one after another till he finds one that fits well. Sometimes two of these crabs come to the same shell, and then they have a fight about it. Very foolish must a crab feel when he has driven an- other one off, and finds, after all, that the shell he has been fight- ing for does not fit his tail. Questions . — What is said about our skin as a covering ? What is said about its fitting well ? Where are there wrinkles, and why ? How is the covering of man’s body different from that of other animals, and why ? What is said about animals in cold climates ? What about those that live in warm countries ? What about the elephant, the monkey, and the horse ? What about the fur of the cat ? What about the covering of birds ? How are the feathers of the wing different from those of the breast, and why ? Why are the feathers of some birds oily ? Tell about the duck and the hen. Wh} r do fishes have scales ? Why are they kept oiled ? Toll about the hermit-crab. 142 BEAUTY OF THE COVERINGS OF ANIMALS. Beauty of some very small insects. Butterflies. Colors in shells. CHAPTER XXVIII. BEAUTY OF THE COVERINGS OF ANIMALS. There is great variety in the coverings of insects. In some the covering is like burnished armor. The variety of colors is exceedingly great, and in many they have a splendid brilliancy. Some of the smallest insects, which most people never notice, are surpassingly beautiful when examined with the microscope. It is with them in this respect as it is with some of the smallest flowers. We know not how much beauty there is all around us in the small things that God has created till we take the micro- scope and look at them. The butterflies are among the most beautiful of insects. Almost every variety of color is to be seen in them, and often many colors are seen together, arranged in the most beautiful manner. You can not have any idea of the great variety of their beauty unless you see some collection of them in cases in some museum. You have often admired the beauty of different shells. These are the coverings of animals who lead a very quiet life in them, as I told you about the oyster. Very splendid are the colors often on the inside of these coverings, and sometimes on the outside also ; and even when the outside is not at all handsome when we get the shell from the water, we often find that clearing off the outer coating with acid, or by nibbing, will show us beautiful colors. Then, too, by grinding the shell in different parts of it, different layers are seen of different hues. BEAUTY OP THE COVERINGS OF ANIMALS. 143 Why God made shells so beautiful. The hoopoe. The beauty of these coverings is of no use to the animals that livain them. They have no eyes to see it. Tor what, then, is it intended ? It is for our gratification. The Creator strews beautiful things even on the bottom of the ocean for us. If the coverings, or houses, as we may call them, of all the animals that live there were as homely as that of the oyster, they would be as useful and comfortable for them as they are now, decked with their elegant colors. So far as they are concerned, the beauty is thrown away. But men gather the shells, and, while they ad- mire them, they see in the beauty which the Creator lavishes even in the depths of the sea the evidence of his abounding goodness. The variety of beauty in the coverings of birds is very great. The various colors are arranged in their plumage in every va- riety of manner, and there are all shades of the colors, from the most brilliant to the most delicate. Commonly the greatest dis- play in the plumage of birds is in the delicate and downy feath- ers of the breast. But the bird that you see here, the hoopoe, has its chief beauty in its crest, which is of an orange color tip- ped with black. It is one of the most elegant of birds. 144 BEAUTY OF THE COVERINGS OF ANIMALS. The beauty of the peacock. Its pride. Its disagreeable voice. In the peacock, a drawing of which you have here, there is a great display of colors. The animal struts about, and, lifting its tail in the air, spreads it like a fan, and seems to be very foolish' Iy proud of its beauty. Proud people generally have something disagreeable about them, and so it is with the peacock. Its voice is so harsh and screeching that no one wants it in his neighborhood. BEAUTY OF THE COVERINGS OF ANIMALS. 145 A bird of paradiso. Its cleanliness. Birds of Paradise, as they are called, are exceedingly beautiful. There are several kinds of them. The most com- mon kind is the one pic- tured here. I will give you an idea of its colors. Most of its body is a rich brown ; the throat is a golden green; the head is yellow ; the long, downy feathers that you see so abundant about the tail are of a soft yel- low color. This elegant bird is very careful to prevent the least speck of dirt from getting on its plumage ; and when it sits on a branch of a tree it always faces the wind, so that its feathers may not be ruffled. There is, I think, in the humming-birds more variety of color than in any other kind of birds. The colors are very brilliant, es- pecially upon the delicate feathers of their breasts ; and they are shaded in the most beautiful manner. I never saw a finer display of colors than I once saw in a collection of humming-birds in a museum in Philadelphia. On the following page is an engraving of a few varieties of these birds. You can see what different shapes they have. They are alike only in their long, slender bills. And 2 K 146 BEAUTY OF TIIE COVERINGS OF ANIMALS. Ilumming-birda. Beauty of the furs of animals. when one sees a large collection of them, with all their varied forms and colors, lie is struck with admiration .and wonder. Many of the furs of animals have much beauty, but there is no such great variety of color as there is in the plumage of birds. As you blow on a fine fur, and see how thickly its delicate fibres stand together, you admire its richness. Each fibre of it is in it- self a beautiful thing. We hardly know why it is that some animals that we dislike so much should have so much beauty. Worms and caterpillars are disgusting to us, and yet in many of them there is a great display of elegant colors. While writing this, I see one crawling along on my coat-sleeve with its numerous feet of curious shape. BEAUTY OP THE COVERINGS OF ANIMALS. 147 A caterpillar. Why such snimals are often very beautiful. Its color is a brilliant green. On its back stand up in a row three beautiful light yellow tufts. Behind these, on a dark stripe, are two fleshy-looking round bunches, that are a most brilliant red. On its side bristle out white hairs in bundles. Its head is red, and from it extend forward dark colored but very delicate feelers, in two bundles. I suppose they are feelers, because they are shaped like the feelers of the butterfly, which you see on page 118. Now why is it 1 hat so much beauty is given to such animals ? It does not seem to be of any use. But this can not be so, for God has a use for every thing that he makes. We are to remem- ber that he can make a thing beautiful as easily as he can make it homely. And it is just this lesson, perhaps, that he means to teach us when he clothes such creatures as worms and caterpil- lars in coverings of beautiful colors. It is different with us. We try to make beautiful only those things that we prize much. There are some things that it would be a foolish waste of time for us to ornament. This is because we can do but little in making things beautiful. But there is no end to God’s power in the crea- tion of beauty. He can, by the word of his power, make just as many beautiful things as he pleases. Questions . — What is said about the variety of colors in insects ? What is said about butterflies ? What about shells ? Is their beauty of any use to the animals that live in them ? Why is so much beauty put in them ? What is said about the variety of colors in the coverings of birds ? Tell about the hoopoe. Tell about the peacock and about the birds of Paradise. What is said about humming-birds ? What is said of the furs of animals? What is said about worms and caterpillars? Why is so much beauty often given to such animals ? 148 HOW MAN IS SUPERIOR TO ANIMALS. Man’s superiority in his mind. Machinery of animals suited to their minds. CHAPTER XXIX. HOW MAN IS SUPERIOR TO ANIMALS. You see, from what I have told you, that man can do with liis hands a great variety of tilings that animals can not do. It has been said, therefore, by some that the hand is the great thing that makes man superior to animals. But this is not true. Of what use would the hand be if there was not a mind in the head that knew how to use it? Suppose that your cat had a hand instead of a paw, could she write with it? No; the mind in her brain does not know enough for this. And so there are a great many other things that we do with our hands which the cat would not know enough to do with hands, if she had them. So, then, it is not the hand merely that makes you superior to a cat, but it is the mind that uses the hand. Your mind knows more than her mind does, and wants to do more things than her mind ever dreams of. Your mind, therefore, needs such an instru- ment as the hand to do these things with, while a paw answers very well for the cat. God gives to every animal just such machinery as its mind can use. If it knows a great deal, that is, if it has a great deal of mind, he gives it a great deal of machinery ; but if it has but lit- tle mind, he gives it but little machinery ; for if he gave it much, it would not knowhow to work it. An oyster, as I have told you, knows but little as it lies covered up in its shell. It knows IIOW MAN IS SUPERIOR TO ANIMALS. 149 Machinery of the oyster, and of the cat and dog. Machinery in the face. how to do only a few things, and so it has but little machinery. A dog or a cat knows a great deal more than an oyster, and there- fore it has paws, claws, teeth, etc., as machinery for its mind to use. And as your mind knows so much more than that of a dog or cat, it has that wonderful machine, the hand, to do what it knows how to do. The mind of man knows so much that it will contrive, when there are no hands, to use other things in place of them. I once saw a man who had no hands write, and do various other things very well Avith his toes. You know that we generally use the right hand most, making the left hand rather the helpmeet of the right. But when the right hand is lost in any way, the mind sets the left to work to learn t§ do as the lost one did. I once had to cut off the right arm of a very bright little girl. But her busy mind did not stop working because it had lost the best part of its machinery. In less than a fortnight I saw her sewing with her left hand, fastening her work with a pin instead of holding it as she used to do. There is some other machinery, besides the hand, that you have which animals have not. It is the machinery that is in the face. I have told you about this before, in the chapter on the muscles. A dog, when he is pleased, looks up at you and wags his tail ; but he can not laugh or even smile ; neither can he frown. Why ? Because there is none of the smiling, and laughing, and frowning machinery there. And so it is with other animals. The variety of work that this machinery of expression does in the face of man is very great, as you can see if you watch the 150 HOW MAN IS SUPERIOR TO ANIMALS. Variety of expression in the face. The wolf. Why we have no snarling muscle*;. varied expressions of countenance in persons engaged in animated conversation. But there is very little variety of expression in the face of an animal. Now why is it that they have not the sams eating.. The cow knows how to use her teeth, and lips, and tongue in eating ; but if she had a mind like yours, she would use them in talking, and would not merely low. The parrot, you know, does know how to talk, after a fashion* This particular faculty is given to it, though it is rather a stupid bud about other things. And, after all, its talking is a very awk- ward imitation of the speech of man ; it only says what it hears people say, and that in a very bungling manner. Though man has more machinery and can do more things than any other animal, there are some things that some animals can do better than he can. Man can climb, but he can not do it as well as a cat or a monkey. He can swim, but not as well as a fish. The frog and the grasshopper are better jumpers. The horse and the dog can run faster than he can. He can not see as far as 152 IIOW MAN IS SUPERIOR TO ANIMALS. Some animals can do things which man can not. some birds. He lias but two eyes, but the fly lias thousands of eyes, so that it can see in almost all directions at once. He can not smell as well as the dog, who can follow the track of his mas- ter by the scent left in his footsteps. He can mimic different sounds, but the mocking-bird cart- beat him at this. But, besides all this, there are some things done by some ani- mals that man can not do at all. He can not fly like the birds and insects. He can not go to roost like the birds. He can not walk along on the wall over his head, as the fly does with the suckers on its feet. Each animal is fitted to do just those things that it needs to do. For example, the monkey needs to climb to get his living, and the Creator has therefore made him so that he can climb very easily. For this purpose, instead of having two hands and two feet, as we have, he has four things shaped somewhat like hands, with which he can grasp the limbs of trees. I might give you other examples, but you can find many in the chapters on what animals use for hands, the tools of animals, and their instruments of defense and attack. Questions . — Wkat is said about the hand ? In what is man superior to animals ? What is said about the machinery that God gives to different animals ? Tell about the man that had no hands, and about the girl that had her arm cut off. What is said about the machinery in the face ? What about the variety of work that this machinery does? Why do not animals have the same muscles of expression that man has ? What muscles of expression do some animals have that man has not ? Why does not man have them ? Why can not animals talk ? What is said about the parrot? Mention some things that some animals can do better than man. Mention some things done by animals that he can not do at all. What is every animal fitted to do ? THE THINKING- OF ANIMALS. 153 What animals think about. The cat and the snow. CHAPTER XXX. THE THINKING OF ANIMALS. You saw in the last chapter that the great superiority of man over other animals is in his mind. Let us look, now, at those things in which their minds are like his, and those things in which they differ from it. I have already told you some things about the thinking of ani- mals. Some of them think a great deal. They think about what they see, and hear, and feel very much as we do. I once had a cat that was born in the spring, after the snow was all gone. In the beginning of the next winter, the first snow that came was quite deep. It fell in the night. It was, of course, a new sight to my cat. When she came out in the morning, she looked at it with very curious eyes, just as we look at any thing new. I sup- pose that she thought how clean, and white, and pretty it was. After looking a little while, she poked the snow first with one paw and then with the other several times, to see how it felt. Then she gathered up between her paws as much as she could hold, and threw it up in the air over her head ; and then she ran swiftly all around the yard, making the snow fly about like feathers wherever she went. Now, though my cat could not talk, I could see by her actions that her thoughts and feelings were very much such as children have when they play in the snow. Animals are much like children in their sports. We notice this very often in dogs and cats. But the same thing is true of other 154 THE THINKING OF ANIMALS. The sport of animals. Sober animals. The Irishman and the owl. animals. It is amusing to see porpoises playing with each othei in the water. As they throw themselves up out of the water, and dive down again, they chase each other as dogs and cats do. Some birds are very lively in their sports. Insects have their sports also. The ants, industrious as they generally are, have their times for play. They run races ; they wrestle ; they carry each other on their backs in the same way that boys do ; they run one after another, and dodge each other behind stalks of .grass, as boys do behind trees and posts ; they have scuffles and mock-fights to- gether. Very busy are their minds in their little brains in these sports — as busy as your minds are in your sports. There are some ani- mals that you never see engaged in sports. Their thoughts seem to be always of the sober kind. You never see toads and frogs play. They always look very grave. The owl is one of the soberest-looking of animals. He looks as if he was consider- ing something. Here is a picture of one. A man once bought an owl, supposing it to THE THINKING OF ANIMALS. 155 The thinking of animals in taking care of their young. be a parrot. Some one asked him, a day or two after, if his par- rot talked yet. No, said he, but he keeps up a great thinking, and I suppose he will speak his thoughts when he gets more ac- quainted. Animals think a great deal in taking care of their young. What care the hen exercises over her brood of chickens ! She has some of the same thoughts and feelings of love that a mother has in taking care of her child. And the bird, that has her little ones in the nest, has many thoughts about them as she goes out to gather food, and then wings her way back to put it into their open mouths. It is interesting to watch canary-birds as they hatch and rear their young. The male bird commonly insists upon it that the female shall sit upon the nest all the time, while he takes upon himself the task of feeding her. A male canary belonging to a friend of mine was excessively particular on this point. He would not let his mate leave the nest for a moment, and if she did he would fight her till she went back. He was exceedingly busy in feeding her, and might certainly be called a good provider. A lady gave me a very interesting account of two orioles that built their nest on a tree close by her father’s house. They came regularly every year to the same spot, and the family always knew the very day of their arrival by their joyous singing. They seem- ed to have the same feelings of joy that people generally do when they return to a much-loved home after a long absence. At one time one of their little ones fell from the nest. The parents man- ifested their concern by flying about in the most hurried, uneasy manner, and making mournful cries. The family pitied the poor 156 THE THINKING OP ANIMALS. The spider. The thinking of animals in building their dwellings. birds, and the little one was carefully picked up, amid the flutter- ings and cries of the old birds, and was replaced in the nest. And now the joy of the parent birds over their restored one was ex- pressed by a long and merry peal of song, as they sat perched on the branch close by their little nestlings. At length one of these orioles died, and the other left the nest and never more returned. See that spider on his web. He is watching for flies. The mind in his little brain thinks of every fly that comes buzzing along, and is anxious that it should get its legs entangled in the snares that he has woven. How glad he feels when he sees one caught by these snares ! And if he thinks that they are not strong enough to hold the fly, he runs and quickly weaves some more threads about him. In the same way do all animals that catch their prey think very busily while they are doing it. Animals think much in building their dwellings. The bird searches for what it can use in building its nest, and in doing this it thinks. The beavers think as they build their dams and their houses. They think in getting their materials, and also in arrang- ing them, and in plastering them together with mud. Questions . — What is said about the thinking of animals ? What is told about a cat? What is said about the sports of animals? Tell about the ants. Tell about the owl. What is said about animals taking care of their young ? Tell about tho canary-bird. Tell about the orioles. What is said about the spider? What is said about animals building their dwellings ? MORE ABOUT THE THINKING OF ANIMALS. 157 Stories about the shepherd’s dog. CHAPTER XXXI. MORE ABOUT THE THINKING OF ANIMALS. As animals think, they learn. Some learn more than others. The clog learns a good deal ; so do the monkey and the elephant. Some are good at learning some particular things. The parrot learns to mimic talking, though it is quite stupid about some other things. The mock- ing-bird learns to imitate a great many different sounds. The shepherd’s dog, seen here, though he does not know as much about most things as dogs of some other kinds, un- derstands particularly well how to take care of sheep. If he is trained to this bu- siness, he will show great skill in doing it. James Hogg, a Scotch poet, commonly called the Ettrick Shepherd, relates many wonderful anecdotes of his dog, whom he called Sirrah. He says that one night a large flock of lambs got out from their fold and ran away among the hills. When the shepherd said, “ Sirrah, they’re a’ awa’!” the dog dash- ed off after them, and was soon out of sight. The shepherd also, 158 MORE ABOUT THE THINKING OP ANIMALS. Animals build always the same way, and have no new fashions. and his man, started off in pursuit. They searched all night, but could find nothing of the dog or the lambs ; but in the morning they espied Sirrah standing guard at the mouth of a gorge, or nar- row pass, and anxiously looking for his master to come. He had succeeded in finding all the scattered lambs, and here they were in this gorge, into which he had driven them. It is told of an- other dog of this kind that he would pick out any stray sheep from the midst of a whole flock, and drive it back to the flock to which it belonged. This dog was once observed trying to drive a flock over a bridge which they were afraid to cross. He managed very well, and at length succeeded in getting them over. It was amus- ing to see how he did it. At one moment he was driving up some of the scattered ones, and the next he was among the foremost, urging them forward. After a while he made some of the fore- most pass over, and then the whole flock followed. Though animals think and learn, they do not have much orig- inality. They always do things very much in the same way. They do not keep contriving some new ways of doing things as men do. Each kind of bird has its own way of building a nest, and it is always the same way. The robins build their nests now just as they did hundreds of years ago. The moles build their tunneled habitations under ground year after year after the plan that you see on page 112. And so of other animals. They have no new fashions, and learn none from each other. But men, you know, are always contriving new ways of building houses, or learning them from other men. Many of the tilings that animals know how to do they seem to MORE ABOUT THE THINKING OF ANIMALS. 159 What is done by instinct. liens hatching duck’s eggs and sitting on pieces of chalk. know either without learning, or without learning in the same way that we learn. They are said to do such things by instinct ; but what instinct really is no one can tell. It is by this instinct that birds build their nests, and bees their honeycombs, and beavers their dams and huts. If these things were all contrived and thought out just as men contrive houses, there would be some changes in the fashions of them, and some improvements. Nearly all that we know about this instinct is that some very nice things are done by it, without much thinking being mixed up with it. This want of thinking sometimes leads to some queer mistakes. If you put a duck’s eggs in a hen’s nest, she will sit on them as if they were her own eggs, and after the ducks are hatched she will take care of them, not seeming to know that they are not chickens. One would suppose that she would know, because they look so different from chickens, and have bills so unlike theirs. But she does not seem to think of this. And it is amusing to see her after the ducks get large enough to go into the water. Off they run, and plunge in, and swim about, while the old hen stands by the water, greatly alarmed lest they should be drowned. She does not understand it ; she does not know that ducklings have an instinct different from chickens. * So, too, if the hen has rounded pieces of chalk put in her nest, she will sit on them as if they were real eggs. Her instinct makes her sit ; but if she had much reason she would not sit on pieces of chalk. If she thought much, she would find out what they were and quit her nest. I have mentioned the building instinct of the beavers. An En- ICO MOKE ABOUT THE THINKING OF ANIMALS. The building instinct of the beaver. IIow the minds of animals differ from ours. glish gentleman caught a young one and put him at first in a cage. After a while he let him out in a room where there was a great variety of things. As soon as he was let out he began to exercise his building instinct. He gathered together whatever he could find, brushes, baskets, boots, clothes, sticks, bits of coal, etc., and arranged them as if to build a dam. Now, if he had his wits about him, as we should say, he would have thought that there was no use in building a dam where there is no water. It is from such mistakes as these that I have mentioned that the instinct of ani- mals is said to be blind. It is plain that, while animals learn about things by their senses as we do, they do not think nearly as much about what they learn, and this is one reason that they do not know as much as we do. Even the wisest of them, as the elephant and the dog, do not think over what they see and hear very much. But this is not all. There are some things that we understand about which animals know nothing. They know nothing about what happened before they were bom, or what happens now in their lifetime away from them in other places. They know noth- ing about what is to happen. They know nothing about God and another world. You can not teach them any thing about any such subjects. The reason is, that while their minds are like ours in some things, they are different in other things. You can see this great difference between your minds and the minds of animals in one thing. You never would think of telling a story to a dog or a cat as you would to a child, for you know that it would not be understood. MORE ABOUT THE THINKING OF ANIMALS. 161 What some wise men are foolish and wicked enough to say. The minds of animals are so much unlike ours that they do not know the difference between right and wrong. Some suppose that a dog will not do certain things because he knows that it is wrong to do them. But this is not so. He is afraid to do what he would be whipped for. If he sees a piece of meat on a table, he will not take it simply because he knows his master would not like it, and not because he knows that it is wrong to steal. I have told you that the mind uses the brain in thinking. Now some learned men have been so foolish as to say that it is the brain itself that does the thinking, just as if our brains, and the brains of all animals, are only so many machines that make thoughts and feelings. Of course, such men do not believe that, after death, the mind or soul of man leaves the body and lives sep- arate from it. They believe that when the body dies there is an end to every thing. But God has told us differently from this in his word, and he knows all about such things ; and those that pretend to know that it is not as God says it is, show great wick- edness as well as folly. Questions . — What is said about the learning of animals ? Tell about the shep- herd’s dog. What is said about the contrivance of animals ? Why do they have no new fashions ? What is said about instinct ? Tell about the hen’s hatching duck’s eggs. Tell about her sitting on pieces of chalk. What is told about tho beaver? What is one reason that animals do not know as much as we do? What things do they know nothing about ? Do they know the difference between right and wrong ? What is said about the notions of some learned men ? 2 L 162 WHAT SLEEP IS FOE. The machinery of the body needs seasons of rest for repairing. CHAPTER XXXII. WHAT SLEEP IS FOR. All animals have their times for sleeping. It would not do for their minds to use the machinery of the body all the time ; if they did, the machinery would soon wear out. The brain, and nerves, and muscles, etc., are all repaired during sleep, so that they may be ready for use again. When you feel tired, it is because your mind has worn the ma- chinery of the body by using it. Now, when you lie down and sleep, the muscles stop working ; no messages pass through the nerves, and the brain is at rest, because the mind pretty much stops thinking. But all this time that you sleep the blood keeps circulating, and the breathing goes on. What is this for ? It is that the repairing of the machinery may be done, so as to get the brain, and nerves, and muscles ready for the work and the play of to-morrow. The repairing, you know, is all done with the blood. This is the material for repairing as well as for building, and there- fore it must be circulating every where while you are asleep, and the breathing must go on to keep the blood in good order. The repairing of the body is going on all the time while you are awake as well as when you are asleep. But it goes on more briskly when the machinery is not in use than when it is. So we may say that when you are asleep the machinery is lying by for a full repair. WHAT SLEEP IS FOR. 163 The night the time for sleep. Why merely keeping still will not answer. The same is true of the building of the body. More of it is done when you are asleep than when you are awake. You are growing all the time, but you grow most when you are asleep. And it is because the child is growing that he needs more sleep than the adult does. The baby is growing very fast, and so he sleeps a great deal of his time in the day as well as in the night. The night is given to us as the time to sleep. Then it is dark and still, and we can go to sleep easily. Most animals sleep through the night. You remember that I told you, in Chapter X., Part First, how still the garden becomes as evening comes on. The flies, and bees, and bugs, and birds have gone to rest, to get repaired for the next day ; so, too, have the larger animals. But it is curious that some animals are busy in the night, and take their sleep in the day. It is so with the owl and the bat. The katydid, you know, does not begin its noise till evening. I sup- pose that it sleeps in the daytime. Those people that stay up late at night, and do not get up early in the morning, make a great mistake. They do not take the right time for sleeping. They ought not to turn night into day, as bats, and owls, and katydids do, for they are not made for it. When you are tired and need sleep, the trouble is not merely in the muscles. If it was, then keeping still merely, without sleep- ing, would answer. But the brain and nerves need repairing as well as the muscles. But as long as you are seeing, and hearing, and feelijig, the nerves are kept too busy to be repaired well ; and as long as your mind keeps thinking, the brain does not get thoroughly repaired. So, then, merely keeping still will only re- 164 WHAT SLEEP IS FOE. Dreaming. The winter sleep of some animals. The long sleep of a toad. pair the muscles ; and sleep is needed to repair the brain and the nerves. You know that when you dream very much you are not as much refreshed as when you sleep soundly. What is the reason ? It is because that when you dream the mind is not wholly at rest, and works the brain, so that it is not thoroughly repaired. There is another kind of sleep into which some animals go. It is a very long sleep. It lasts all winter. Great numbers of such animals as frogs, bats, flies, and spiders, go into by-places in the fall to sleep till spring comes. Many of the birds do this. It is a deeper sleep than that which animals go into at night. It is a different kind of sleep. In the sleep at night the blood keeps moving, and the animal breathes ; but in this winter sleep there is no breathing, and the blood stops circulating. All is as still as death. But there is life there, just as I told you, in Part First, there is life in the seed, and in the trees that look so dead in winter. It is life asleep. The warmth of spring wakes up again the life in these animals, as it does the life in the trees. The blood then begins to circulate in them, as the sap does in the trees, and they come out from their hiding-places. I have said that this sleep which some animals go into lasts through the winter. It may be made to last longer than this. Some frogs were once kept in this winter sleep for over three years in an ice-house ; and then, on being brought out into the warm air, revived and hopped about as lively as ever. We do not know how much longer they might have been kept in this sleep. You re- member that in Part First, Chapter XV., I told you about some WHAT SLEEP IS FOR. 165 The winter sleep of some animals not perfectly sound. seeds in which the life was asleep many hundred years. And it may be that the life might be kept asleep in frogs and other ani- mals as long as this by steady cold. A toad was found lately in the middle of a tree fast asleep. How he came there was not known, but the wood had kept growing year after year, and as there were 67 rings outside of the toad, it was clear that he had been there 67 years. A long sleep it was, but he soon woke up and hopped about like other toads. There are some kinds of animals that crawl into winter quar- ters in whom life is not wholly asleep. The blood moves a little, and they once in a while take a breath ; and, besides, they now and then, when the weather is quite warm, wake up enough to eat a little. Now it is curious that such animals always lay up some- thing to eat right alongside of them when they go into their win- ter sleeping-places. But those who do not wake up at all do not lay up any food, for it would not be used if they did lay it up. They are governed by instinct in this matter. The field-mouse lays up at its side nuts and grain when it goes into its winter quarters, and when it is partly waked up by a warm day, eats a little of his store. The bat does not lay up any thing, although he wakes up when it is warm. He does not need to lay up any thing, because the warmth that wakes him up wakes up also gnats and insects on which he lives. He catches some of these, and then, as he finds himself going to sleep again, he hangs himself up by his hooks as before. The marmot or wood- chuck does not wake up at all, but he always lays up some dried grass in his hole. What is this for? He feeds on it when he 166 WHAT SLEEP IS FOR. How much life is asleep in the winter. Flight of birds south in winter. first wakes up in the spring, to get a little strength before he comes out from his hole. How much life, then, is asleep in the winter in animals as well as in plants ! And how busy is life in its waking in the spring ! While the roots and seeds in the ground send up their shoots, and the sap again circulates in the trees and shrubs, and the buds swell, multitudes of animals are crawling out of their winter hiding- places into the warm, balmy air. And when the leaves are fully out, and the flowers abound, the earth swarms with the busy in- sects, and birds, and creeping things, of which we saw none during the winter. Some of the birds that we see in the spring have not been asleep during the cold weather, but have spent their winter at the South, and have now winged their way back to spend their summer with us. They go back and forth in this way every year, guided by that wonderful and mysterious thing, instinct. How this makes them take their flight at the right time, and in the right direction, we do not understand. Questions .— Why do animals need sleep ? Why do you feel tired after work, or play, or study ? Why does the blood circulate and the breathing go on in sleep ? When is most of the repairing of the body done ? How is it with its growth ? What is said about night as the time for sleep ? Mention some animals that sleep in the day and are awake in the night. What is said about people that turn night into day? Why would not merely keeping the body still, without sleeping, answer for our rest? What is said about dreaming? What is said of the winter sleep of some animals ? Tell about the frogs and the toad. Why do some animals take food into their winter sleeping-places ? Tell about the field-mouse, the bat, and the marmot. What is said about the waking up of life in the spring in animals and in plants ? What is said about the birds ? THE CHILD’S BOOK OF NATURE, FOR THE USE OF FAMILIES AND SCHOOLS. INTENDED TO AID MOTHERS AND TEACHERS IN TRAINING CHILDREN IN THE OBSERVATION OF NATURE. IN THREE PARTS. PART III.— AIR, WATER, HEAT, LIGHT, &c. By WORTHINGTON HOOKER, M.D., AUTHOR OP “FIRST BOOK IN CHEMISTRY,” “CHEMISTRY,” “NATURAL PHILOSOPHY,’ * “NATURAL HISTORY,” ETC. iXJitl) Illustrations. NEW YORK: HARPER & BROTHERS, PUBLISHERS, FRANKLIN SQUARE. 18 8 2 . By Dr. WORTHINGTON HOOKER. THE CHILD’S BOOK OF NATURE. For the Use of Families and Schools; intended to aid Mothers and Teachers in training Children in the Observation of Nature. In threa Parts. Illustrations. The Three Parts complete in one vol., Small 4to, Cloth, $1 00; Separately, Cloth, Part I., 40 cents; Parts II. and III., 44 cents each. Part I. PLANTS.— Part II. ANIMALS.— Part III. AIR, WATER, HEAT, LIGHT, &o. FIRST BOOK IN CHEMISTRY. For the Use of Schools and Families. Revised Edition. Illustrations. Square 4to, Cloth, 44 cents. NATURAL HISTORY. For the Use of Schools and Families. Illustrated by nearly 300 Engravings. 12mo, Cloth, 90 cents. SCIENCE FOR THE SCHOOL AND FAMILY. Part I. NATURAL PHILOSOPHY. Illustrated by nearly 300 Engravings. 12mo, Cloth, 90 cents. Part II. CHEMISTRY. Revised Edition. Illustrations. 12mo, Cloth, 90 cents. Part III. MINERALOGY AND GEOLOGY. Illustrations. 12mo, Cloth, 90 cents. Published by HARPER & BROTHERS, Franklin Square, N. Y. Either of the above volumes will be sent by mail, postage prepaid , to any part of the United States or Canada , on receipt of the price. Entered, according to Act of Congress, in the year one thousand eight hundrd and fifty- seven, by Harper & Brothers, in the Clerk’s Office of the District Court of the Southern District Court of New York. PREFACE. There is no obvious connection between the subjects now to be considered and those which were presented in Parts First and Second. But, after looking at what is of interest in the plants and animals that live in air and water, it seems appropriate to pass to the examination of the phenomena that air and water themselves furnish to us. And then with these subjects are nat- urally associated the other subjects contained in this Part — light, heat, electricity, etc. Let me not be understood to say that the subjects treated in this Part are entirely disconnected from those in the other two Parts. There are many points of connection, resulting from the dependence of life upon air, water, heat, etc., and also from the me- chanical principles that are brought into- operation in the living machinery of both plants and animals. Still, the connection is not of that obvious and intimate character which we see between the subjects of Parts First and Second. I have placed these subjects last in the Child’s Book of Nature because they are not, for the most part, so easily understood as the subjects contained in the other Parts. The mind of the learn- er needs the training in observation and reasoning which it has in studying the phenomena of plants and animals to enable it to IV PREFACE. grasp all of the points which are here presented ; and as in mat- ter, so in style, I have supposed an advance of mental power in the learner. I have relaxed a little my strictness in simplicity. Indeed, I did so in a small degree in the Second Part. I have been careful, however, not to allow myself too much latitude in this respect, but have endeavored throughout to make the advance both in style and matter to correspond with the advance of mental capacity in the learner, and not go beyond it. The subjects of this Part are those which are commonly ranged under the general term Natural Philosophy. They are not pre- sented either formally or fully, but those points are selected which will interest a young beginner and be intelligible to him. I have made it an object to exclude all that are of a different character, for it is very important that the young learner should not be dis- couraged with difficulties and burdened with uninteresting matters at the outset. It will be seen, however, that in making the selection alluded to, I have, after all, given quite a full view of the fundamental parts of the different subjects. The simple principles which form the basis of Natural Philosophy are most of them very fully illus- trated. And I can not forbear remarking that many older schol- ars, who have pursued the study in the more formal manner com- mon in our schools, might find their ideas rendered more clear and definite by looking at the simple views here presented. I would call the attention of the teacher to one feature in my mode of developing scientific subjects to the young, which I deem to be of great importance. I observe a natural gradation in their’ development, beginning with the simplest views, and leading the PREFACE. V learner gradually to those that are more complex and less easily understood. Not only is one thing given at a time, but each thing is put in its right place. I will cite a single example. Take what is said about air. First, the simple and single fact that it is a material thing is illustrated. This is followed by noticing what it does when in motion. Then I show how, by its resist- ance, birds and insects rise on the wing. Next I pass to the pressure of the air, first illustrating, in a simple way, the fact of its pressure in all directions, and then passing to show how its pressure operates in the pump and in the barometer. Then come illustrations of its pressure as exhibited in experiments with the air-pump, the immense pressure which the body sustains from it, and the manner in which it does this being especially noticed and explained. Next follows the elasticity of the air when compress- ed, illustrated by the operation of pop-guns, air-guns, etc. Then is illustrated the pressure of the air in making balloons, bubbles, and other light things rise in it. This leads naturally to the con- sideration of the rising of smoke and the operation of chimneys. And then, lastly, in the latter part of the book, the action of the attraction of gravitation upon the air is noticed, thus ultimately arriving at the real cause of most of the phenomena of the air’s pressure. Another feature, to which I will barely allude, is a frequent ref- erence to analogies. Thus, for example, in giving the facts about air, I point out the resemblance between flying and swimming, be- tween the action of compressed air and that of compressed steam, and of the gases produced by burning powder, etc. This feature not only adds interest to the various subjects, but makes the VI PREFACE. points in hand more clear, and gives a wider range to the views of the learner. It is the author’s intention to follow this with other books cal- culated to carry forward the scholar in his observation of nature. Indeed, I have already published two books, “ First Book in Phys- iology” and “ Human Physiology,” by which the scholar can pro- ceed with the study of the subjects treated of in Part Second of this book ; and as soon as I can do so, I shall write some books for the purpose of enabling him to go on with the study of the subjects treated of in the other Parts. The whole together will constitute to some extent a series of books on the sciences, adapt- ed to the different degrees of advancement in the pupils. It will be observed that in this Part there are many experiments spoken of. These the teacher should try before the pupils so far as is practicable. I have also made extensive use of common phe- nomena as illustrations of the points presented. This will tend to form in the scholar the habit of observing what is just around him — the common things, so much overlooked in education — a habit which is a never-failing source of information and enjoyment. And both teacher and scholar, if they catch the spirit which I have endeavored to infuse into the book, will from their own observa- tion add to the illustrations that I have given, and thus material ly increase the interest of the daily recitations. Worthington Hooker. CONTENTS, CHAPTER TAGS I. AIR 9 II. AIR IN MOTION 13 III. FLYING AND SWIMMING 18 IY. THE PRESSURE OF THE AIR 25 Y. PUMPS 30 YI. THE BAROMETER 3G VII. THE AIR-PUMP 39 VIII. GASES 44 IX. POWDER 48 X. POP-GUNS 53 XI. BALLOONS AND BUBBLES 57 XII. MORE ABOUT BALLOONS 63 XIII. HEATED AIR 68 XI Y. CHIMNEYS 72 XV. USES OF WATER 77 XYI. WATER ALWAYS TRYING TO BE LEVEL 81 XVII. THE PRESSURE OF WATER 87 XVIII. ATTRACTION IN SOLIDS AND FLUIDS 92 XIX. WATER IN THE AIR 97 XX. CLOUDS 101 XXI. SNOW, FROST, AND ICE 105 XXII. HEAT AND COLD 110 XXill. THE DIFFUSION OF HEAT * H4 Vlll CONTENTS. CHAPTER PAGE XXIV. WHAT HEAT DOES 120 XXV. STEAM 125 XXVI. LIGHT 130 XXVII. COLOR 135 XXVIII. MORE ABOUT COLOR 130 XXIX. ELECTRICITY 144 XXX. MORE ABOUT ELECTRICITY 150 XXXI. MAGNETISM 155 XXXII. GRAVITATION 159 XXXIII. THE MOTION OP THE EARTH 165 XXXIV. FRICTION 172 XXXV. CONCLUSION 176 THE CHILD’S BOOK OF NATURE. PART III— AIR, WATER, HEAT, LIGHT, ETC. E speak of a room having no furniture in it as being empty ; but this is not exactly so. There is one thing that it is full of up to its very top. It is a thing that you can not see ; but it is as really a thing as the furniture that you can both see and feel. This thing is air. If you take all your books out of a box in which you keep them, you think of the box as having nothing in it ; but it is full of air ; and when you shut it up and put it away, you put away a box full of air. When the books were in it, it was full of books and air together ; but now it is full of air alone. You see some boys playing foot-ball. What is it that they are kicking about ? It is an India-rubber ball, you will say. But is this all ? Is there not something else besides the India-rubber ? Suppose that you prick a hole in the ball. It is good for noth- ing now ; but the India-rubber is all there. What makes it good CHAPTER I. AIK. Air, a thing. 10 AIR. Life-preservers. Boats. Life boats. for nothing ? It is because the air escapes from the hole. The ball is of no use unless you can keep it full of that thing that we call air ; and in playing with it, you kick about air locked up in the India-rubber. You have heard of life-preservers, and perhaps you have seen them. They are India-rubber bags that you can fill with air by blowing into them. They are made of such a shape that they can be tied around the body. When used in this way, a life-preserver will keep one from sinking in water. But why ? It is the air in it that does this. The air is as really a thing as the water is, but it is a lighter thing, and therefore a thing full of air will float on the water. If you kick a foot-ball into the water, it will float, because it is full of that light thing — air. But if you should prick a hole in it, and press out the air, and then throw it into the water, it would sink. So, too, the life-preserver would do no good if you tie it around you without blowing it up. It is the air that you blow into it that buoys you up in the water. Why does a boat float on the water? It is not because the boat itself is lighter than the water is. It is commonly heavier, because there is so much iron about it. The reason that it floats is that it is full of air. Even a boat made entirely of iron will float for the same reason. But if there should be a leak, so that the boat can be filled with water, it will sink. So, too, it will sink if you put too much weight in it. You have heard of life-boats. These are made in such a way that they will not sink, even if they are filled with water. How do you think that they are made to be so much lighter than other AIR. 11 > IIow life-boats are made. We can feel air, but can not see it. boats? It is not because they are built of different materials. They are made of wood, and are fastened together in every part I with iron. Sometimes they are made entirely of iron. But they are built in a different way from common boats. They are made double, and in such a way that there are chambers of air between the two parts. These chambers are air-tight. If they were not they would do no good. If there were any opening into these chambers, the water would go in and force out the air. The boat would no longer be a life-boat. It would be of no more use than a life-preserver with no air in it, or with water instead of air. You can not see air, although it is a thing; but you can some- times feel it. You can not feel it while it is still, as you can such things as a table or water. You can only feel it when it is in motion. When the wind blows upon you, it is air in motion that you feel. When there is a gust of wind, as we say, the air comes against you just as a wave of water does. When you fan yourself, you make the air strike upon your face, and you feel it as you feel any thing else that strikes you, as water or a stick. The air is transparent, or clear, like glass; that is, it lets the light come through it to your eyes. Sometimes glass is not clear, and you can not see things plainly through it. So, also, the air is sometimes not clear, as when there is dust flying in it, or when there is a fog. Though you can not see air, you can see what it does when it is in motion. You can see it move the trees and other things. This I will tell you about in the next chapter. 12 AIR. Air necessary to life. Nothing can burn without air. The air is a thing which is necessary to our life. If it be shut out in any way from our lungs, great distress is immediately pro- duced ; and if it be shut out only for a few minutes, death occurs. I have told you in Part II., in the chapter on breathing, why it is that breathing air is so necessary to life. Air is as necessary to the life of plants as it is to the life of animals. In animals the air is used by lungs, but in plants it is used by the leaves. This I have told you about in the chapter on the uses of leaves, in Part I. Air is needed for another thing. Nothing can burn without air. It is the air that makes wood, and coal, and oil, and gas burn when fire is put to them. The air that is all around the earth does not reach to the sun, and moon, and stars. It extends about forty-five miles above the earth. Beyond this there is no air. You will want to know how this was found out, as no one has ever been so far from the earth. I will not explain this to you now, for you are not old enough to understand it. Questions . — What is a room full of when the furniture is all taken out? Tell about the box of books and about the foot-ball. What is said about life-preservers ? Why does a boat float on the water ? How are life-boats made ? Can you see air ? Can you feel it when it is still ? What is wind ? What is said about the transparency of air ? What is said about its being necessary to the life of animals ? What about its being necessary to the life of plants ? What else is air needed for ? How high does the air extend ? AIR IN MOTION. 13 How a ship is moved along by air. CHAPTER II. AIR IN MOTION. The air, when it is in motion, does a great deal of work for us. It pushes along the ships in the water. Perhaps you think that it hardly sounds right to say that the air pushes the ships ; but it really does push them. The sails are large, broad handles for the 14 AIR IN MOTION. A coat used as a sail. Trees blown by the wind. air to press against in pushing the vessels along in the water. On the preceding page is a ship with many sails, and most of them are unfurled, or put out for the breeze to press upon. The air would push a vessel along to some extent, even if there were no sails, by pressing or blowing against the body of the vessel ; but, unless the wind blew very strong, the air would not push it along very fast in this way. And so sails are put up on masts, that more of the air may get hold, as we may say, so as to press on the vessel. Sometimes the wind helps you along as you are walking. Now, if you take hold of your coat, and spread it out wide, as you see this boy is doing, it will be like a sail, and the wind will carry you along faster, because there is more for the air to press upon. So, too, if you have an umbrella open when the wind is blowing on your back, it will be to you as the sail is to the ship. But if you are going against the wind, the outspread coat and the open umbrella would prevent your getting along fast. When a tree is bare, the wind scarcely moves its branches ; but how it bends when it is full of leaves and the wind blows strong- ly upon it ! It is then like a ship with its sails all unfurled ; there is a great deal for the air to press upon. Sometimes w T e say the wind blows very hard or very strong ; AIR IN MOTION. 15 Fast-moving air. The bullet. The locomotive. this is when the air moves very fast. The faster it moves, the more it will do. This is so with other things. When you strike any thing very hard with a stick, you do it by making the stick move fast. When there is only a gentle breeze, that you can just feel, the air is moving very slowly ; it is like the gentle touch with the stick. But when the wind blows so hard that you can scarce- ly stand up, the air is moving very fast. If a bullet is tossed to you, it will not hurt you to catch it, be- cause it does not move very fast ; but if a bullet shot from a gun should hit your hand, it would wound it, and perhaps go through it. The reason is, that the bullet moves so fast. The faster it moves, the more harm it will do. So the air, when it moves very fast indeed, is apt, like the bullet, to do harm. You have seen a locomotive backed up against a train of cars to be hitched on. It does no damage, because it is backed up slowly. It only gives a little jerk, you know, to the whole train. Now, if it moved very fast, it would, when it came to the cars, break them to pieces. It is for the same reason that fast-moving air roots up trees, blows down houses, and drives ships on shore, dashing them against the rocks. When the wind blows hard, the sailor takes in some of his sails. The vessel would go too fast if he left them all out, because there would be so much for the air to press on. If the wind blows very hard indeed, he takes down all the sails, fastening them very tight- ly, so that the wind may not loosen them. Even with all the sails down the ship will go quite fast enough, perhaps even too fast, pushed along by the wind that strikes right upon it. Here is a 16 AIR IN MOTION. Ship in a storm. How waves are made. ship in a storm. You see how the sailors have tied up most of the sails. One of them has been torn from its fastenings by the violence of the wind, and is in tatters. The waves that you sometimes see rise so high are made by ^the striking of the air upon the water; and the faster the air moves over the water, the higher they rise. When the air is very still there is scarcely a ripple, and the water looks like smooth glass ; and you would hardly think, as you look upon it, that AIR IN MOTION. 17 Small and great whirlwinds. such a light thing as air is could whip it into such waves as you sometimes see. The waves in the ocean are much higher than they are in a river. This is because the wind blows over so much greater an extent of water in the ocean. You have heard of whirlwinds. In these the air moves in a whirling way instead of straight forward. You sometimes see lit- tle whirlwinds in the street ; and as shavings and other light things are whirled about in them, and are carried up in the air, you can imagine what damage large whirlwinds can do, twisting up trees and tearing houses in pieces. As you can not see the air, and it is a very light thing, you commonly think of it as being almost nothing, and yet it does these great things that I have mentioned. When we see this light thing raise the waves, and move the heavy ships along so swiftly, we see that there is great power in it. Questions . — How does the air make a ship go ? What is the need of sails ? What is said about the air’s helping you along in walking ? Why does the wind bend a tree so much that is covered with leaves ? What is true about the air when the wind blows hard? Give the comparison about the stick, the bullet, and the loco- motive. Why does the sailor take down some of his sails when the wind blows hard ? What is said about weaves ? Why are they higher in an ocean than in a river ? What is said about whirlwinds ? 8 B 18 FLYING AND SWIMMING. How wings raise the birds in the air. Why they are so large. CHAPTER III. FLYING AND SWIMMING. You can jump off from the ground just a little way into the air, but you can not fly into it, as the birds do. It is because you have no wings. But how is it that the birds fly with their wings ? They push themselves up with them into the air. But perhaps you will say that they do not have any thing to push against, for there is nothing but air about them. Now it is the air itself that they push against. They press down upon the air with their wings, just as you press with your feet on the ground when you jump up ; and as the bird, when it gets once started, keeps work- ing its wings, it goes up and up, pushing down against the air each time that its wings are moved. It is necessary that birds should have very large wings to raise themselves up thus in the air. If their wings were small, they would do no good, because they would not press upon enough of the air. You can move your hands in the same way that the bird does its wings, but you can not raise yourself off from the ground. Why? Because your hands are so small that they press only upon a little of the air. If your hands were as broad for you as the wings of birds are for them, and you had the proper muscles to work them, you could fly. You can learn to fly, but it is in the water, and not in the air, that you can do it. Swimming is really flying in water. The FLYING AND SWIMMING. 19 Flying in water. The kite. The tail of a fish like a sculling oar. hands and feet do for the swimmer what the wings do for the bird. He presses against the water with his hands and feet in the same way that the bird does against the air with its wings. Some- times you see a bird dive down from a great way up in the air, in the same way that the swimmer does in the water. When it does this its wings are very still, and are folded close to its side, as you see here in the kite ; but when it goes up again it works its wings up and down, just as the swim- mer works his feet and hands when he is rising in the water. Fishes swim chief!)/ The tail is to a fish in the water what wings are to a bird in the air. It acts like a sculling oar in a boat, as I told you in Part Second, Chapter XXIII. The fins are the balancers, while the tail works the fish forward by its quick movements to one side and the other. You can see this very plainly if you watch gold-fishes as you see them in a glass vessel. Observe why it is that you can not fly with your hands in the air in the same way that you can swim with them in the water. with their tails. 20 FLYING AND SWIMMING. Why we can not fly in the air with our hands. The water gives way under your hands just as the air does, but the air gives way much more easily than the water, because it is so much lighter. As the air gets out of the way so easily, you can not fly in it unless you have something very broad, so as to press down on a great deal of it at the same time. To fly, you must have large wings instead of small hands. You can see what a difference there is between hands and wings by trying a little experiment. Move about your hand in the air. You do it with perfect ease, and the air does not seem to resist the hand at all. Now take a large palm-leaf fan and move that about. You can not do this so easily as you moved your hand, unless you move it edgewise. Why is this ? Because it presses upon so much more air than your hand does, and the resistance of so much air to the fan you can feel as you push it out of the way. The fan takes hold, as we may say, of more air than your hand does, and so does also the wing of a bird. Did you ever think how large wings you would need to fly with ? You would have to press upon a great deal of air to carry your body up as the birds do theirs. See how large the wings of a bird are, as they are stretched out. They are both very long and very broad ; and, besides, the bird is not so large as he seems to be. You will see this if all the feathers are stripped from its body. If this be done while the wings are left whole, it will seem to you that it takes very large wings to raise a very little body. You can see, then, that it would require very large wings indeed to carry your body up in the air; and still larger ones to carry up a man. FLYING AND SWIMMING. 21 Wings of the swift. Wings of the bat. Here is a bird that flies so fast that it is called the swift. Its wings, you see, are very long. You do not see how broad they are, be- cause they are not fully spread out in the figure. But there is no ani- mal that has a greater extent of wing than the bat, unless it be some of the insects. This is the reason why it flies so swiftly. You can see in this figure of the long -eared bat what a large amount of air its wings press upon as it works them. The wings of insects that fly very swiftly are very large in proportion to their bod- ies. This you can see in the butterfly that flies so nimbly from flower to flower. Those that fly rather slowly, as the bumble-bee, have not very large wings. 22 FLYING AND SWIMMING. The flying fish. The flying squirrel. X believe that there is only one kind of fish that can fly in the air, It is represented here. You can see that the fins with which it flies are not nearly so large as the wings of a bird of the same size would be. It therefore can not fly very high or far. The ~~ highest that it was ever known to fly is twenty feet, and usually it skims along only two or three feet above the water. It does not go up into the air in the same way that a bird does. It gets its upward start from the water, and all that it does with its wing-like fins is to keep itself up, which it sometimes does for perhaps five or six hundred feet. It takes this flight in the air in fleeing from some large fish, and in this way often es- capes being devoured. That beautiful animal, the flying squirrel, which you see here, has a fold of skin extend- ing from the fore leg to the hind leg on each side. These folds FLYING AND SWIMMING. 23 Shape of the wings of birds. How they are used in flying. answer somewhat as wings when they are stretched out. Very graceful is the movement when the animal takes a long, flying sweep from one tree to another. But he can not go up in the air as a bird does, for the folds are not nearly so large as real wings, and so do not press upon enough air to carry him up. He can only take the sweep that I have mentioned. Observe the shape of the wings of birds. They are rather rounded on the upper surface, and hollowed out underneath. They are shaped in this way to make the flying easy. This I will ex- plain to you. When raising the wing, the air goes easily off from the rounded surface ; but when it is moved downward, the air can not get away easily from the hollowed surface. The wing gets hold, as we may say, of some of the air, and, pressing upon it, raises up the bird. You can see how this is by moving an open umbrella in the air. You can move it very easily if you push the outer rounded sur- face straight forward against the air. This is because the air moves off from the round surface of the umbrella as easily as it does from the upper surface of the bird’s wing. But if you move the um- brella with the inner hollowed surface against the air, you find it rather hard work. Why ? It is because the air is caught in the hollow of the umbrella as it is in the hollow of the bird’s wing. But this is not all. The bird, in raising its wing, does not move it straight upward. It moves it in such a way that it rather cuts the air with its forward edge. It does this to get it up with little resistance from the air. But when it moves it downward, it wants to get as much resistance from the air as it can, so it moves it 24 FLYING AND SWIMMING. How the hands are used in swimming. straight down, and not edgewise. You can see liow this works by moving a palm-leaf fan about in the air. Move it edgewise, and it goes very easily. This is like the upward motion of the bird’s wing. But move it broadside against the air, and you feel con- siderable resistance. That is, the air resists the pressure of the fan, just as it resists the pressure of the wing in the downward stroke. The swimmer manages his hands in the water in the same way that the bird does its wings in the air. When he raises his hands forward, he does it edgewise ; but when he presses them down, he moves them flat against the water, so as to press upon as much water as he can. Questions . — How is it that birds fly ? Why do they have large wings ? Why can you not fly? How is swimming like flying? What do fishes swim with? Why can not you fly in the air as well as swim in the water ? Tell about the experiment with the fan. What is said about the size of birds’ wings ? Tell about the bird called the swift. Tell about the bat. What is said about the flying fish ? What about the flying squirrel ? What is said of the shape of wings of birds ? Give the comparison of the umbrella. Tell how the bird moves its wings upward and dowiv- vrard. Give the comparison of the fan. Give the comparison about swimming. THE PRESSURE OF THE AIR. 25 Air presses in wherever room is made for it. CHAPTER IY. THE PRESSURE OF THE AIR. The air is every where. It is always ready to go where there is room made for it. If we move a bureau or any thing out of a room, the air fills up all the place where it stood. If you make a hole in any thing, the air at once presses in to fill it up. Every crack and crevice is filled with air. You know how much water a sponge will hold. There are a great many little cells or spaces in it that hold the water. Now squeeze the water out, and as the water goes out of these cells, the air presses into them and fills them up. So, too, if you have any liquid in a barrel, just so fast as you draw it off, the air goes in to take its place. When you pull the handles of a pair of bel- lows apart, as represent- ed here, you make more space in the bellows, and the air rushes in to fill up this space. It is the same with breathing. When 26 THE PRESSURE OP THE AIR. Air easily moved out of the way. Why it is easier to walk in air than in water. you breathe in, or draw a breath, as we say, the air goes down into your lungs through the windpipe. This is because the chest is made larger as it heaves, and so there is more room in the lungs; and the air goes in to fill up this room, just as it does in the bel- lows. When the air moves very fast, it is, you know, often very in- convenient, and sometimes does much harm, as when houses are blown down, or when ships are driven upon a rocky shore. But commonly it is very accommodating. It is so easily moved out of the way that we do not think of its being in the way at all. When you are walking, your body pushes the air one way and the other, just as a man pushes persons to the one side and the other when he goes through a crowd ; and as the people close up behind him as he moves along, so the air closes up behind you as you walk through it. Now, if the crowd were facing him, and should push against him, he would find it slow and hard work to get through. So, when the wind blows strongly in your face, it is hard walking, and you get along slowly, because the air presses against you so hard. The air is pushed out of the way easily because it is so light. This is the reason that it is easier to walk in air than in water. The water, as you wade in it, is pushed to the one side and the other, as the air is when you walk in it ; Tut it is not done so quickly and easily ; and, as it is easier to walk with the wind than against it, so it is easier, in a running stream, to wade down stream than up against the current. J The air is so light a thing that you hardly think of it as press- THE PRESSURE OF THE AIR. 27 Experiments showing the pressure of the air. ing on any tiling ; but it does press on every thing. Let us see what this pressure does. See this glass tube. It is open at the end which is in the vessel of water, but it is closed at the oth- er end. It is full of water. But water is apt to run what makes it stay up in this tube ? It is kept up by the air that presses on the water in the vessel. If you could take away the air from all about the vessel, the water in the tube would come down into the vessel, because there would be nothing there to hold it up. There is another way in which the water in the tube can be the top of the tube, and the air will go into it, and make the water run down by pressing on it. Even if it be only a pin-hole, the air, ready to go in every where, will rush in, and down the water wi 11 all go. Now you can not very well make a in the top of the tube, but you can try the ex- ment in another way, so as to show what let- ed here. You take a glass tube open at both cnuS. Covering one end tight with the palm of your hand, you fill the tube with water. Then carefully put the other end under water, and hold it as you see here. The water will stay up in the tube as long as you keep the palm of your hand down whenever it can get a chance to do it. Now made to run down into the vessel. Let a little hole be made in the air in will do. The experiment is repre- 28 THE PRESSURE OP THE AIR. Experiment showing that the air presses upward as much as downward. tight over the top of it ; but loosen your hand, and the air will go in and push down the water into the vessel. You can see, from what I have told you, why a vent-hole is needed in a barrel from which we draw any liquid. If the barrel be tapped, the liquid will not run out, unless the air can get in above so as to press it out. Till the vent-hole is made, the liquid will stay in, just as the water stays up in the tube in the experi- ment. When w^e make the vent-hole, we do the same to the bar- rel as we should do to the tube if we should make a little hole in the top of it, or as you do to the tube in the second experiment when you loosen your hand at the top of it to let the air in. This pressure of the air that I have told you about is in every direction. It is upward and sideways as well as downward. r This may be shown by another experiment with a glass tube, as represented here. Fill the tube with water, and then place carefully over its open end a smooth slip of paper. You can then turn it over so that the open end shall be downward, as seen in the figure, and the water will not run out. What is the reason of this ? It is because the pressure of the air on the paper keeps the water in. We can often suc- ceed with this experiment with a wine-glass, or even a common tumbler, though we can do it more easily with something that has a smaller opening. But you will ask, perhaps, this question : If it be the pressure of the air that keeps the water from running out, what need is there of the paper ? The paper merely serves to keep the surface THE PRESSURE OF THE AIR. 29 How bubbles of air rush in among the particles of a liquid. of the water smooth and whole. If the paper were not there, the air would get in between the parts of the water, and would rush up and force the water out. For the same reason, if, instead of the small hole commonly made in tapping, a large hole be made in the barrel, the liquid will run out without any vent-hole. In this case, the air has a chance to work itself in among the parts or particles* of the liquid, and go in bubbles up into the upper part of the barrel. A mere slip of paper put on the hole would keep the liquid in, as in the case of the tube or the wine-glass, and for the same reason. You know that there is a gurgling sound made when a liquid is poured from a jug or a bottle. This is caused by the bubbles of air that pass in while the liquid is coming out. Questions . — What is said about the air’s being every where? Tell about the sponge and the barrel. How is breathing like using a pair of bellows ? What is said about the ease with which air is moved out of the way ? Give the comparison about going through a crowd. Why is the air pushed out of the way so easily ? What is said about wading in water? Tell about the experiment with the glass tube open at one end. Why is a vent-hole needed in a barrel when we want to draw off what is in it ? Give the comparison to the experiments with the tube. How can you show that the air passes upward and sideways as well as downward? What does the paper do in this experiment ? Why is there no need of a vent-hole when a large opening is made in a barrel ? What makes the gurgling when a liquid is poured from a jug or a bottle ? * I explain about the particles of water farther on, in the 16 th and 17 th chapters. 30 PUMPS. Explanation of the operation of sucking. CHAPTER Y. PUMPS. You know that you can suck up water or any fluid through a straw or any other tube. Now what is it that makes the water go up through the tube into your mouth ? I will tell you. When you put the tube into your mouth it is full of air, and so long as the air is there the water will be kept out ; but when you suck you remove the air from the tube ; and as the air goes out, the water comes in, following right on after the air. But what makes the water come in ? Does it come in of itself because there is room made for it? No. Water can not move itself. It must be moved by something else. It is the air pressing on the water in the vessel you are sucking from that pushes it up into the tube. You do not really draw up the water. You get the air out of the way in the tube, and then the air that is all the time pressing on the water in the vessel pushes it up into your mouth. As soon as you stop sucking, and take your mouth from the tube, the wa- ter that is in the tube will run down into the vessel, because it is pressed down by the air that goes in at the top of the tube. You know that you have to suck commonly several times be- fore the water will reach your mouth. If the tube is a very large one, you suck a great many times to get all the air out of it. At first you suck out a little of the air in the tube, and the water is pushed up to take its place ; then you suck a little more out, and PUMPS. 31 IIow pumping is like sucking. more water is pushed up, and so on till it reaches the top of the tube. Here is a boy that has partly filled his tube, and one more suck would bring the fluid to his mouth. You can now see how we pump up water out of a well or cistern. The wa- ter is not drawn up, but it is pushed up just as it is in the tube when you suck. When you work the han- dle, you do the same thing for the pump that your mouth does for the tube in sucking any liquid ; and when the pump has not been worked for some time, you have to move the handle up and down several times before the water comes, just as you have to suck several times to fill a tube of any length with water. I will show by some figures how a pump operates. In the first figure the hand is raising the handle, as you know we always do when we begin to pump. The raising of the handle, you see, makes the piston, as it is called, go down in the pump. Here it is going down through air, for the water has not as yet got up as far as the piston. Now, if this piston were a whole solid piece of wood, it would do no good, for it would press the air down before 32 PUMPS. The operation of a pump explained. water; and when the piston press- es down, the only way for it to get out of the way is to press upon that little door, and go up above the piston. Well, the handle is up. The next thing is to bring it down, as represented in this picture. As the handle goes down, the piston it. But it is not solid. It has a hole through it, and a sort of clapper or valve on the hole. Therefore, as the piston goes down, the air pushes up the valve, and goes up through the hole. You see that this air is shut in between the piston and the PUMPS. 33 Explanation of the pump continued. goes up, as you see. You remember that I told you that, as the piston was going down, as seen in the first figure, some of the air went up through the hole and got above the piston. Now this air can not get down again, for the moment that the piston begins to move up, the air, pressing on the valve, shuts it down. Now, as the piston goes up, there is room made below it. How is this room filled ? The air that is there, as you see, rises up to fill it, and the water follows the air. The next moving of the pis- ton down will carry it below all the air and down into the water ; and the water will go up through the little door, just as the air has done before it. Then the moving of the piston up will carry this water so high as to make it run out of the mouth of the pump, as seen in this figure. But there is a valve in the pump that I have said noth- ing about as yet. This lower talve operates in this way: As the air or the water goes up in the pump, the valve is pushed open by it, as you see in the second figure and in the C 34 PUMPS. How the tongue in sucking acts like the piston of a pump. last one ; but when the piston works down, as seen in the first figure, this valve is shut, so that all the water that gets above it is safe, and can not go back. What is it that makes the air and the water rise in the pump ? All that gets above the piston is lifted up by the piston, as you see. But what makes that rise which is below the piston ? It is the pressure of the air on the water in the well or cistern. This pushes up the water as fast as there is room made for it. If a cistern were full of vrater, and were air-tight also, you could not pump up the water from it. You must have air there to push up the water, or it will not come up when you make room for it by working the pump. You see, then, that sucking and pumping are very much alike. In the pump the piston makes the room for the air and the water to be pushed up into. Now, when you suck, there is a piston that operates very much as the piston of a pump does. Your tongue is the piston. See how this is. When you suck through a tube held in water, you move your tongue in such a way as to make a space in the mouth, and the air in the tube is pushed in to fill up this space ; and when the air is all pushed in, the water is pushed in after it. Both are pushed in, as I have before told you, by the air pressing on the water in the vessel. It is just as water is pushed up into a squirt-gun when you draw the piston. This pis- ton does in the gun, when you draw it, the same thing that your tongue does in your mouth when you move it in sucking. It • makes space, and the water is pushed into the gun, as it is into the mouth, to fill up this space. The way in which the space is made PUMPS. 35 The common language about sucking and pumping incorrect. in the mouth in sucking is this. Before you begin to suck, the tongue fills the mouth, so as to be up against its roof ; but when you suck, you move the tongue down from the roof of the mouth, and this makes a space there ; and whatever is in the tube, wheth- er it be air or water, is pushed in to fill this space. The common language, then, which is used about sucking and pumping is not exactly correct. When we suck or pump, it seems to us as if the liquid was drawn up, and so we use the word draw in regard to it. So, too, we talk about the suction or drawing power. But, as I have showed you, the liquid is pushed up in- stead of being drawn. All that the piston in a pump does is to make room. It does not draw the water into that room, but the pressure of the air forces it in. Whenever there is any room made, the air is always ready either to go in itself or to force some- thing else in. Questions . — Explain the operation of sucking up water through a tube. Why does the water in the tube run down into the vessel when you stop sucking and take your mouth away ? Why is it that you commonly have to suck several times before the water reaches your mouth ? How is pumping like sucking ? What is shown by the first figure ? What by the second ? What by the third ? Explain the opera- tion of the lower valve of the pump. What makes the air and the water rise in the pump ? Why would they not rise if the cistern were full and were air-tight ? Ex- plain how the tongue acts as a piston in sucking. Give the comparison about the squirt-gun. What is said about the language used about sucking and pumping ? 36 THE BAROMETER. Pressure of the air holds up water in the pump and mercury in the barometer. CHAPTER VI. THE BAROMETER. Water can be raised in a pump only to a certain height, and the mistake has sometimes been made of getting the pump so long that it would not work. If it be more than about thirty-four feet from the water up to the piston, the water can not be made to go up so high. What is the reason ? It is because the air, pressing on the surface of the water in the cistern or well, will raise it only to the height of thirty-four feet. It does not press hard enough to force it up any higher. Suppose you had a glass tube over thirty-four feet long, with one end open, and used it as represented in the first experiment in Chapter IV., on page 27. The water would be kept up in it only the thirty-four feet. The weight of a column of water of that height just balances the pressure or weight of the air. Above that height in the tube there would be a space in which there would not be any thing. Quicksilver or mercury, as perhaps you know, is a fluid like wa- ter, but very much heavier. The pressure of the air, therefore, will hold up a column of this not nearly as high as the column of wa- ter it holds up. The column of mercury held up in a glass tube is not quite three feet long, while that of water is thirty-four feet. You can now understand how the instrument called a barom- eter is made. The object of this is to tell how heavy the air is, THE BAROMETER. 37 Barometer on a mountain. Air heavier at some times than at others. for the air is heavier at some times than it is at others. A fv glass tube, open at one end, and about three feet in length, Sr is taken, and is filled with the mercury. Then the open Ij: end is put into a dish of mercury, as seen in the figure. || There will be a space in the tube above the mercury, as | represented, for the air will support by its pressure a col- 1 umn of only about thirty inches of mercury — six inches [I less than three feet, the length of the tube. A scale, di- vided into inches, is added, as seen in the figure ; and the whole, neatly inclosed in a case, makes what we call a barometer. This means a measurer of the pressure or weight of the air. If the barometer be carried up a mountain, the mercury falls. Why is this ? It is because there is less height of air pressing on the mercury than there is in the valley below, and of course it will not hold up so long a column of mercury. In the valley, as I have told you in Chapter I., the air is forty-five miles high ; and if we carry the barometer up a mountain three or four miles high, it will make a difference of several inches in the height of the mer^ cury in the tube. I have said that the air is heavier at some times than at others. In a bright, clear day, the air is heavy, and then the mercury rises high, or, rather, is pushed up high in the tube. But when it is cloudy and rainy, the mercury falls, for the air is then lighter than usual, though people often say at such a time how heavy the air is. The truth is that we feel better when the air is clear and heavy, and so the air seems light to us. On the contrary, we do not feel so well when it is cloudy and the air is light. 38 THE BAROMETER. How the barometer is of use to the sailor. The barometer is of use to the sailor in telling him of threaten- ed storms ; for when a storm is coming the air is light, and the mercury in the barometer falls of course. The sailor, therefore, looks now and then at his barometer, and if he at any time sees the mercury fall suddenly, he gets ready for a storm, for he knows that it may come on very rapidly. Dr. Arnot says that he was once on board of a vessel where the captain was enabled to save his ship and all on board because he took warning in season from his barometer. The sun had just set, and, as the evening was very pleasant, all on board were enjoying themselves in various ways. But the captain’s orders were given to take down sails and pre- pare for a storm. All were astonished, for nobody could see any signs of a storm. But the captain had seen the mercury sink down very suddenly in his barometer, and he knew that trouble was coming, and probably very soon. He hurried the men, therefore, but the storm came before he was quite ready. It was a violent hurricane. But the ship, though much damaged, was saved, and in the morning the wind was still, and all were rejoicing in their deliverance. Probably, if the captain had not looked at his ba- rometer, the ship, with all on board, would have been lost. Questions . — How high can water he raised in a pump ? Why can it not he raised higher ? Tell about the experiment with a long glass tube. How high a column of mercury will the pressure of the air hold up ? Explain the barometer. Explain y water and air. Earth moves round the sun without friction. Friction is not confined to solid substances. Any substance can make friction. Water can do it. The rocks over which it Hows, or against which it dashes, are worn by its constant friction, just as the constant friction of passing feet in the course of years wears the stone steps of a building which is much frequented. Air, too, makes friction. It is by friction that the air, moving along over the smooth water, raises it into waves ; and it is the friction of the air, as it passes over a field of grain, that gives it the wavy motion which makes it so beautiful. Wherever there is motion on the earth, it is lessened more or less by friction. Nothing moves without rubbing something, but this is not so with the earth as it goes around the sun. As it flies through space so swiftly, it rubs against nothing, not even against air, for the air, as I have told you, goes along with it. Questions . — What does friction do ? What is said about walking on ice ? What about sleighing and sliding down hill ? What is the contrivance for making heav- ily-loaded carts go down steep hills safely ? How does the steam make the loco- motive go ? What is the difference between the driving-wheels and the small wheels? What comparison is made about these two kinds of wheels? How do the driving-wheels move the locomotive along ? What is said about the rails being too smooth? How is the difficulty remedied? How is it after the locomotive is well agoing when the rails are slippery ? What is the comparison about running on the ice? How do brakes operate in stopping the cars? What else is done when they want to stop the cars quickly ? What is said about greasing and oiling wheels ? What is said about the joints of machinery and the joints of our bodies ? What is said about the friction of water on rocks? What about the friction of air? What is true of all motion on the earth ? What is said about the earth as it goes around the sun ? 176 CONCLUSION. Very many things to he learned in this world. CHAPTER XXXV. CONCLUSION. I have thus, in the Three Parts of this book, described to you some of the wonderful things that are all around you upon the earth and in the water. But there are many more things than I have described. In this book you have only begun to learn what is in the world, and you could not learn all if you should study all your lifetime, and even if your life should be as long as Methuse- lah’s was. But I hope that you will go on to learn as much as you can. With your mind wide awake, you will see and hear, as you go about from day to day, a great many interesting things that I have not mentioned. I have told you about many things in plants ; but if you look at different plants as you meet with them, you will soon see that you can learn much about them that you can not find any where in this book. So, also, if you watch animals, large and small, as you see them, you will find many more interesting things in them than I have told you. And the same is true of the subjects of the Third Part — air, water, light, etc. I have only opened to you a few of the leaves in the Book of Nature, and you can go on to open more of them for yourselves. To know much about things, you must not merely look at therm You must examine them — that is, you must think while you look. You must think what this is for and what that is for. In this way you can find out a great deal for yourselves. You will not CONCLUSION. 177 Think while you look. Every fact valuable. merely see that what I and others tell you is true, but you will find out things that no one has told you, and perhaps some things that no one has found out before you. Newton, who found out so many things that men did not before know, always thought about things as he saw them; and so did Franklin, wdio, as you remem- ber, discovered that lightning is electricity. They began early, when they were children, to think while they looked. They had a habit of doing it. If they had not, they would not have been such discoverers. Though perhaps none of you may ever discov- er as many things or as great things as they did, any of you may make some discoveries. Though your discoveries may be small ones, they are not to be despised. They will be worth something. Every fact that is found out is of some value . And if you al- ways think while you see and hear, you may find out for your- selves many facts, and some of them may prove to be of great value. Sometimes a fact that would appear to be of no value turns out to be worth a great deal. Most people would not think that there was much to be learned from a hen’s muddy tracks on a pile of sugar ; but, as you remember I told you in Part First, Chapter XXIX., some one observed the fact that the sugar was whitened wherever the tracks were, and thought about this fact ; and the result was that moistened clay came to be used in every sugar re- finery in whitening sugar. One that is in the habit of thinking while he looks will find something interesting wherever he goes. He will not be obliged to go to some museum to see wonderful things, but he will find 3 M 178 CONCLUSION. Much to be learned that is not in books. Knowing the reasons of things. them all about him. In the most common plants and animals, which most people do not think of much, he will see many things to interest and astonish him ; and to him the air and the water, and even the stones under his feet, will be full of wonders. You see by what I have said that there is a great deal to be learned that is not in books. Indeed, books will not do you much good if they do not wake up in you a disposition to learn more than they tell you. People that know much are not content with learning merely what they find in books, but learn what they can from every body and from every thing. They use books only as helps, and the most of what they know they learn by observing — that is, seeing and thinking upon what they see. It is very pleasant to know the reasons of things. I have therefore told you in this book, as I have gone along, as much as I could do, why things are as I have described them ; but you will remember that I have now and then said about some things that you are not old enough yet to understand them. As you grow older you can learn more and more, and so the things that you will be interested in will be all the time increasing. But, though you may keep on learning all your lives, there are some things that you never can understand. God understands the rea- sons of every thing, but there are many, very many things that the wisest of men can not explain. Very wise men are not apt to be proud of their wisdom. They commonly’ feel that what they know is very little when it is com- pared with what they do not know. Newton was one of the wis- est men that ever lived. He was so wise that he discovered more CONCLUSION. 179 "What Newton said about what he knew. Our knowledge in another world. things than any other man ever has. But he was very humble about his knowledge. He said this about it : He felt that what he knew was like a few pebbles that he had picked up on the sea-shore, and that there was so much of what he did not know that it was like the great ocean that was before him. You remember that I told you in Part Second that all that we know we learn by the senses of our bodies — the sight, the hear- ing, etc. But the glorified bodies which the Bible says that we shall have in another life will be fitted with better means of get- ting knowledge. Some things that are mysterious to us now we shall then understand. We shall know more than Newton and all the wise men of this world ever knew here, and we shall ever be learning more and more of the wonders of God’s power, and wisdom, and goodness. Questions . — What is said about learning all that is in the world ? How can you learn about things for yourselves ? What is said about Newton and Franklin ? Can you make some discoveries ? What is said about the value of facts ? What about finding wonders all around us ? How can books help you to learn more than is in them? What is said about understanding the reasons of things? What is said about the feelings of very wise men? Tell what Newton said about his knowl- edge. What is said about our getting knowledge in another world ? THE END. * V 1 * F -