3. The Cuticle.—Our bodies, like trees, have two skins, or really one skin with an outer and an inner layer. When a person burns himself so as to make a blister, the outer skin, called the cuticle, is separated from the inner by a quantity of water or serum poured out from the blood. This causes the blister to rise above the surrounding skin. If you puncture the blister the water runs out. Now we may easily remove the cuticle and examine it. The cuticle, we shall find, looks very much like the skin which lines the inside of an egg-shell, and it is almost as thin.

4. The cuticle is very thin in most parts of the body, but in some places, as the palms of the hands and the soles of the feet, it is quite thick. This is because these parts of the skin come in contact with objects in such a way as to be liable to injury if not thus protected. The cuticle has no blood-vessels and very few nerves. With a fine needle and thread you can easily take a stitch in it without making it bleed or causing any pain.

5. The Pigment.—The under side of the cuticle is colored by little particles of pigment or coloring matter. The color of this pigment differs in different races. In the negro, the color of the pigment is black. In some races the pigment is brown. In white persons there is very little pigment, and in some persons, called albinos, there is none at all.

6. The Inner or True Skin.—The inner skin, like the inner bark of a tree, is much thicker than the outer skin. It is much more important, and for this reason is sometimes called the true skin. It contains nerves and blood-vessels.



7. The Sweat Glands.—If you look at the palm of the hand you will see many coarse lines, and by looking much closer you will see that the palm is completely covered with very fine ridges and furrows. Now, if you examine these ridges with a magnifying-glass, you will find arranged along each ridge a number of little dark spots. Each of these points is the mouth of a very small tube. This is called a sweat duct. These ducts run down through both the outer and inner layers of the skin. At the under side of the true skin the end of the tube is rolled up in a coil, as you can see by looking at the illustration on the following page. The coiled parts of the tubes are called sweat glands, because they separate from the blood the fluid which we call sweat or perspiration.

8. The Oil Glands.—There are other little glands in the skin which make fat or oil. The oil is poured out upon the skin to keep it soft and smooth.



9. The Hair.—There are some curious little pockets in the skin. Out of each of these pockets grows a hair. On some parts of the body the hairs are coarse and long; on other parts they are fine and short.

10. Many of the ducts leading from the oil glands open into the pockets or pouches from which the hairs grow. The oil makes the hair soft and glossy. Nature has thus provided an excellent means for oiling the hair.

11. The hair is chiefly useful as a protection. It is also an ornament.

12. The Nails.—The nails of the fingers and the toes grow out of little pockets in the skin just as the hairs do. Both the hair and the nails are really parts of the outer skin, which is curiously changed and hardened. The nails lie upon the surface of the true skin and grow from the under side as well as from the little fold of skin at the root of the nail. They are made to give firmness and protection to the ends of the fingers and toes. The nails of the fingers are also useful in picking up small objects and in many other ways.

13. Uses of the Skin.—The skin is useful in several ways:

(1) It Removes Waste.—The sweat glands and ducts are constantly at work removing from the blood particles which have been worn out and can be of no further use. If we get very warm, or if we run or work very hard, the skin becomes wet with sweat. In a little while, if we stop to rest, the sweat is all gone. What becomes of it? You say it dries up, which means that it has passed off into the air. Sweating is going on all the time, but we do not sweat so much when we are quiet and are not too warm, and so the sweat dries up as fast as it is produced, and we do not see it. Nearly a quart of sweat escapes from the skin daily.

(2) Breathing through the Skin.—We breathe to a slight extent through the skin. There are some lower animals which breathe with their skins altogether. A frog can breathe with its skin so well that it can live for some time after its lungs have been removed. Breathing is an important part of the work of the skin, and we should be careful, by keeping it clean and healthy, to give it a good chance to breathe all that it can.

(3) The Skin Absorbs.—The skin absorbs many substances which come in contact with it, and hence should be kept clean. If the foul substances which are removed in the sweat are allowed to remain upon the skin, they may be taken back into the system and thus do much harm.

(4) The Skin has Feeling.—When anything touches the skin we know it by the feeling. We can tell a great many things about objects by feeling of them. If we happen to stick a pin into the skin we feel pain. We are also able to tell the difference between things which are hot and those which are cold. Thus the sense of feeling which the skin has is very useful to us.

(5) The Skin Protects the Body.—The skin is a natural clothing which protects us much better than any other kind of clothing could. It is so soft and pliable that it cannot hurt the most delicate part which it covers, yet it is very strong and tough.

SUMMARY.

1. The skin is the covering of the body. It has two layers, the outer, called the cuticle, and the inner, called the true skin.

2. A substance called pigment is found between the two skins. This gives the skin its color.

3. The true skin has blood-vessels and nerves, but the cuticle has no blood-vessels and very few nerves.

4. In the true skin are glands which produce sweat, and others which make fat, or oil.

5. The nails are really a part of the skin. They are firm and hard, and protect the ends of the fingers and the toes.

6. The hair grows from the true skin. The hair is made soft and glossy by oil from the oil glands of the skin.

7. The skin is a very useful organ. It removes waste matters, it breathes, it absorbs, it has feeling, and it protects the body.



CHAPTER XVI.

HOW TO TAKE CARE OF THE SKIN.

1. Uses of the Pores of the Skin.—Many years ago, at a great celebration, a little boy was covered all over with varnish and gold leaf, so as to make him represent an angel. The little gilded boy looked very pretty for a short time, but soon he became very sick, and in a few hours he was dead. Can you guess what made him die? He died because the pores of his skin were stopped up, and the sweat glands could not carry off the poisonous matter from his body.

2. Cleanliness.—Did you ever know of a boy who had his skin varnished? Not exactly, perhaps; but there are many boys who do not have their skins washed as often as they ought to be, and the sweat and oil and dead scales form a sort of varnish which stops up the little ducts and prevents the air from getting to the skin, almost as much as a coat of varnish would do.

3. The Sweat Glands.—The sweat glands and ducts are like little sewers, made to carry away some of the impurities of the body. There are so many of them that, if they were all put together, they would make a tube two or three miles long. These little sewers drain off almost a quart of impurities in the form of sweat every day. So you see that it is very important for the skin to be kept clean and healthy.

4. Bathing.—A bird takes a bath every day. Dogs and many other animals like to go into the water to bathe. Some of you have seen a great elephant take a bath by showering the water over himself with his trunk. To keep the skin healthy we should bathe frequently.

5. When we take a bath for cleanliness it is necessary to use a little soap, so as to remove the oil which is mixed up with the dry sweat, dead scales, and dirt which may have become attached to the skin.

6. It is not well to take hot baths very often, as they have a tendency to make the skin too sensitive. Bathing in cool water hardens the skin, and renders one less likely to take cold.

7. The Clothing.—The skin should be protected by proper clothing, but it is not well to wear more than is necessary, as it makes the skin so sensitive that one is liable to take cold.

8. The Proper Temperature of Rooms.—It is also very unwise for a person to keep the rooms in which he lives too warm, and to stay too much in-doors, as it makes him very liable to take cold when he goes out-of-doors. One who is out of doors in all kinds of weather seldom takes cold.

9. Care of the Hair and the Nails.—The scalp should be kept clean by thorough and frequent washing and daily brushing. Hair oils are seldom needed. If the skin of the head is kept in a healthy condition, the hair requires no oil.

10. The habit of biting and picking the fingernails is a very unpleasant one, and keeps the nails in a broken and unhealthy condition. The nails should be carefully trimmed with a sharp knife or a pair of scissors.

11. Effects of Narcotics and Stimulants upon the Skin.—Alcohol, tobacco, opium, and all other narcotics and stimulants have a bad effect upon the skin. Alcohol often causes the skin to become red and blotched, and tobacco gives it a dingy and unhealthy appearance.

SUMMARY.

1. If the pores of the skin are closed, a person will die.

2. We should bathe often enough to keep the skin clean.

3. We should not keep our rooms too warm, and should avoid wearing too much clothing.

4. Alcohol, tobacco, and other stimulants and narcotics injure the skin.



CHAPTER XVII.

THE KIDNEYS AND THEIR WORK.

1. The Kidneys.—The kidneys are among the most important organs of the body. They are in the cavity of the abdomen, near the back-bone, up under the lower border of the ribs. Perhaps you have seen the kidneys of a sheep or a hog. If you have, you know very nearly how the kidneys of our own bodies appear.



2. The Work of the Kidneys.—The work of the kidneys is to separate from the blood certain very poisonous substances, which would soon cause our death if they were not removed. It is very important to keep these useful organs in good health, because a person is certain to die very soon when the kidneys are in any way seriously injured.

3. How to Keep the Kidneys Healthy.—One way of keeping the kidneys in good health is to drink plenty of pure water, and to avoid eating too much meat and rich food. Pepper, mustard, and other hot sauces are very harmful to the kidneys.

4. Importance of Keeping the Skin Clean.—The work of the kidneys is very similar to that of the skin; and when the skin does not do its full duty, the kidneys have to do more than they should, and hence are likely to become diseased. For this reason, persons who allow their skins to become inactive by neglecting to bathe frequently are apt to have disease of the kidneys.

5. Effects of Alcohol and Tobacco upon the Kidneys.—A piece of beef placed in alcohol soon becomes dry and hard, and shrivels up as though it had been burned. The effect upon the kidneys of drinking strong liquor is almost the same. Beer and hard cider also do the kidneys harm, sometimes producing incurable disease of these important organs.

SUMMARY.

1. The kidneys somewhat resemble the skin in their structure and in their work.

2. The kidneys remove from the blood some poisonous substances.

3. To keep the kidneys healthy we should drink plenty of water, avoid irritating foods and drinks, and keep the skin in health by proper bathing.

4. The drinking of strong liquors often causes incurable disease of the kidneys.



CHAPTER XVIII.

OUR BONES AND THEIR USES.

1. The Bones.—In an earlier chapter we learned something about the bones. This we must try to recall. You will remember that we called the bones the framework of the body, just as the timbers which are first put up in building a house are called its frame.

2. The Skeleton.—All the bones together make up the skeleton. (See page 95.) There are about two hundred bones in all. They are of many different shapes. They vary in size from the little bones of the ear, which are the smallest, to the upper bone of the leg, which is the largest in the body.

3. The skeleton is divided into four parts: the skull, the trunk, the arms, and the legs. We must learn something more about the bones of each part.

4. The Skull.—The skull is somewhat like a shell. It is made of a number of bones joined together in such a way as to leave a hollow place inside to hold the brain. The front part of the skull forms the framework of the face and the jaws. In each ear there are three curious little bones, which aid us in hearing.

5. The Trunk.—The bones of the trunk are, the ribs, the breast-bone, the pelvis, and the back-bone. The bones of the trunk form a framework to support and protect the various organs within its cavities.

6. The Ribs.—There are twelve ribs on each side. The ribs join the back-bone at the back. They are connected by cartilage to the breast-bone in front. They look somewhat like the hoops of a barrel. With the breast-bone and the back-bone they form a bony cage to contain and protect the heart and the lungs.

7. The Pelvis.—The pelvis is at the lower part of the trunk. It is formed by three bones, closely joined together. The large bones at either side are called the hip-bones. Each hip-bone contains a deep round cavity in which the upper end of the thigh-bone rests.

8. The Back-bone.—The back-bone, or spinal column, is made up of twenty-four small bones, joined together in such a way that the whole can be bent in various directions. The skull rests upon the upper end of the spinal column. The lower end of the back-bone forms a part of the pelvis.



9. The Spinal Canal.—Each of the separate bones that make up the back-bone has an opening through it, and the bones are so arranged, one above another, that the openings make a sort of canal in the back-bone. By the connection of the spinal column to the head, this canal opens into the cavity of the skull. Through this canal there passes a peculiar substance called the spinal cord, of which we shall learn more at another time.

10. The Arms.—Each of the arms has five bones, besides the small bones of the hand. They are the collar-bone, which connects the shoulder to the breast-bone, the shoulder-blade, at the back of the shoulders, the upper arm-bone, between the shoulder and the elbow, and the two lower arm-bones, between the elbow and the wrist. There are eight little bones in the wrist, five in that part of the hand next to the wrist, and fourteen in the fingers and thumb.

11. The Legs.—The bones of the leg are the thigh or upper leg-bone, the knee-pan or knee-cap, which covers the front of the knee, the two bones of the lower leg, the heel-bone and six other bones in the ankle, five bones in that part of the foot next to the ankle, and fourteen bones in the toes.

12. Use of the Bones.—The skeleton is not only necessary as a framework for the body, but it is useful in other ways. Some of the bones, as the skull, protect delicate parts. The brain is so soft and delicate that it would be very unsafe without its solid bony covering. The spinal cord also needs the protection which it finds in the strong but flexible back-bone. The bones help to move our hands and arms, and assist us in walking.

13. The Joints.—The places where two or more bones are fastened together are called joints. Some joints we can move very freely, as those of the shoulder and the hip. Others have no motion at all, as those of the bones of the skull.

14. Cartilage.—The ends of bones which come together to form a joint are covered with a smooth, tough substance, which protects the bone from wear. This is called gristle or cartilage. You have, no doubt, seen the gristle on the end of a "soup-bone" or on one of the bones of a "joint of beef."

15. The joint contains a fluid to oil it, so that the ends of the bones move upon each other very easily. If the joints were dry, every movement of the body would be very difficult and painful.

16. The bones are held together at the joints by means of strong bands called ligaments.

17. How the Bones are Made.—The bones are not so solid as they seem to be. The outside of most bones is much harder and firmer than the inside. Long bones, like those of the arms and the legs, are hollow. The hollow space is filled with marrow, in which are the blood-vessels which nourish the bone.

18. An Experiment.—If you will weigh a piece of bone, then burn it in the fire for several hours, and then weigh it again, you will find that it has lost about one third of its weight. You will also notice that it has become brittle, and that it seems like chalk.

19. Why the Bones are Brittle.—The hard, brittle portion of a bone which is left after it has been burned contains a good deal of chalk and other earthy substances, sometimes called bone-earth. It is this which makes the bones so hard and firm that they do not bend by the weight of the body. When we are young, the bones have less of this bone-earth, and so they bend easily, and readily get out of shape. When we get old, they contain so much bone-earth that they become more brittle, and often break very easily.

20. A person's height depends upon the length of his bones. The use of alcohol and tobacco by a growing boy has a tendency to stunt the growth of his bones, so that they do not develop as they should.

SUMMARY.

1. There are about two hundred bones in the body.

2. All together they are called the skeleton.

3. The skeleton is divided as follows:

a. The skull.

{ Ribs. b. The trunk. { Breast-bone. { Pelvis. { Back-bone. { Collar-bone. { Shoulder-blade.

{ Upper arm-bones. c. The arms. { Lower arm-bones. { Wrist. { Hand and fingers.

{ Thigh. { Knee-pan. d. The legs. { Lower-leg bones. { Ankle, including heel-bone. { Foot and toes.

4. The bones are useful for support, protection, and motion.

5. The place where two bones join is called a joint.

6. The tough substance which covers the ends of many bones is called cartilage or gristle.

7. The joints are enabled to work easily by the aid of a fluid secreted for that purpose.

8. The ends of the bones are held together in a joint by means of ligaments.

9. Bones are about two thirds earthy matter and one third animal matter.

10. The use of alcohol and tobacco may prevent proper development of the bones.



CHAPTER XIX.

HOW TO KEEP THE BONES HEALTHY.

1. Composition of the Bones.—Our bones, like the rest of our bodies, are made of what we eat. If our food does not contain enough of the substances which are needed to make healthy bone, the bones will become unhealthy. They may be too soft and become bent or otherwise misshapen. This is one of the reasons why bread made from the whole grain is so much more healthful than that made from very fine white flour. In making fine white flour the miller takes out the very best part of the grain, just what is needed to make strong and healthy bones. Oatmeal is a very good food for making healthy bones.

2. Bones of Children.—Sometimes little children try to walk before the bones have become hard enough to support the weight of the body. This causes the legs to become crooked. In some countries young children work in factories and at various trades. This is wrong, because it dwarfs their growth, and makes them puny and sickly.

3. Improper Positions.—The bones are so soft and flexible when we are young that they are very easily bent out of shape if we allow ourselves to take improper positions in sitting, lying, or standing. This is the way in which flat and hollow chests, uneven shoulders, curved spines, and many other deformities are caused.



4. In sitting, standing, and walking, we should always take care to keep the shoulders well back and the chest well expanded, so that we may not grow misshapen and deformed. Many boys and girls have ugly curves in their backbones which have been caused by sitting at high desks with one elbow on the desk, thus raising the shoulder of that side so high that the spine becomes crooked. The illustrations on this and the following page show good and bad positions and also the effects of bad positions.



5. Seats and Desks.—The seats and desks of school-children should be of proper height. The seats should be low enough to allow the feet to rest easily upon the floor, but not too low. The desk should be of such a height that, in writing, one shoulder will not be raised above the other. If a young person bends the body forward, he will, after a time, become round-shouldered and his chest will become so flattened that the lungs cannot be well expanded.



6. Standing on one foot, sitting bent forward when reading or at work, sleeping with the head raised high upon a thick pillow or bolster, are ways in which young persons often grow out of shape.



7. The Clothing.—Wearing the clothing tight about the waist often produces serious deformities of the bones of the trunk, and makes the chest so small that the lungs have not room to act properly. Tight or high-heeled shoes also often deform and injure the feet and make the gait stiff and awkward.

8. Broken Bones.—By rough play or by accident the bones may be broken in two just as you might break a stick. If the broken parts are placed right, Nature will cement them together and make the bone strong again; but sometimes the bones do not unite, and sometimes they grow together out of proper shape, so that permanent injury is done.

9. Sprains.—In a similar manner the ligaments which hold the bones together, in a joint, are sometimes torn or over-stretched. Such an accident is called a sprain. A sprain is a very painful accident, and a joint injured in this way needs to rest quite a long time so that the torn ligaments may grow together.

10. Bones out of Joint.—Sometimes the ligaments are torn so badly that the ends of the bones are displaced, and then we say they are put out of joint. This is a very bad accident indeed, but it often happens to boys while wrestling or playing at other rough games.

11. Children sometimes have a trick of pulling the fingers to cause the knuckles to "crack." This is a very foolish and harmful practice. It weakens the joints and causes them to grow large and unsightly.

12. When a man uses alcohol and tobacco, their effects upon the bones are not so apparent as are the effects upon the blood, the nerves, and other organs; but when the poisonous drugs are used by a growing boy, their damaging influence is very plainly seen. A boy who smokes cigars or cigarettes, or who uses strong alcoholic liquors, is likely to be so stunted that even his bones will not grow of a proper length and he will become dwarfed or deformed.

SUMMARY.

1. To keep the bones healthy they must have plenty of healthful food.

2. The whole-grain preparations furnish the best food for the bones.

3. Walking at too early an age often makes the legs crooked.

4. Hard work at too early an age stunts the growth.

5. Bad positions and tight or poorly-fitting clothing are common causes of flat chests, round shoulders, and other deformities.

6. Tight or high-heeled shoes deform the feet and make the gait awkward.

7. The bones may be easily broken or put out of joint, or the ligaments may be torn by rough play.

8. Alcohol prevents healthy growth.



CHAPTER XX.

THE MUSCLES AND HOW WE USE THEM.

1. The Muscles.—Where do people obtain the beefsteak and the mutton-chops which they eat for breakfast? From the butcher, you will say; and the butcher gets them from the sheep and cattle which he kills. If you will clasp your arm you will notice that the bones are covered by a soft substance, the flesh. When the skin of an animal has been taken off, we can see that some of the flesh is white or yellow and some of it is red. The white or yellow flesh is fat. The red flesh is lean meat, and it is composed of muscles.

2. The Number of Muscles.—We have about five hundred different muscles in the body. They are arranged in such a way as to cover the bones and make the body round and beautiful. They are of different forms and sizes.

3. With a very few exceptions the muscles are arranged in pairs; that is, we have two alike of each form and size, one for each side of the body.

4. How a Muscle is Formed.—If you will examine a piece of corned or salted beef which has been well boiled, you will notice that it seems to be made up of bundles of small fibres or threads of flesh. With a little care you can pick one of the small fibres into fine threads. Now, if you look at one of these under a microscope you find that it is made of still finer fibres, which are much smaller than the threads of a spider's web. One of these smallest threads is called a muscular fibre. Many thousands of muscular fibres are required to make a muscle.



5. Most of the muscles are made fast to the bones. Generally, one end is attached to one bone, and the other to another bone. Sometimes one end is made fast to a bone and the other to the skin or to other muscles.

6. The Tendons.—Many of the muscles are not joined to the bones directly, but are made fast to them by means of firm cords called tendons. If you will place the thumb of your left hand upon the wrist of the right hand, and then work the fingers of the right hand, you may feel these cords moving underneath the skin.

7. What the Muscles Do.—With the left hand grasp the right arm just in front of the elbow. Now shut the right hand tightly. Now open it. Repeat several times. The left hand feels something moving in the flesh. The motion is caused by the working of the muscles, which shorten and harden when they act.

8. All the movements of the body are made by means of muscles. When we move our hands, even when we close the mouth or the eyes, or make a wry face, we use the muscles. We could not speak, laugh, sing, or breathe without muscles.

9. Self-acting Muscles.—Did you ever have a fit of sneezing or hiccoughing? If you ever did, very likely you tried hard to stop but could not. Do you know why one cannot always stop sneezing or hiccoughing when he desires to do so? It is because there are certain muscles in the body which do not act simply when we wish them to act, but when it is necessary that they should. The muscles which act when we sneeze or hiccough are of this kind. The arm and the hand do not act unless we wish them to do so. Suppose it were the same with the heart. We should have to stay awake all the while to keep it going, because it would not act when we were asleep. The same is true of our breathing. We breathe when we are asleep as well as when we are awake, because the breathing muscles work even when we do not think about them.

10. The stomach, the intestines, the blood-vessels, and many other organs within the body have this kind of muscles. The work of these self-acting muscles is very wonderful indeed. Without it we could not live a moment. This knowledge should lead us to consider how dependent we are, each moment of our lives, upon the delicate machinery by which the most important work of our bodies is performed, and how particular we should be to keep it in good order by taking proper care of ourselves.

SUMMARY.

1. The flesh, or lean meat, is composed of muscles.

2. There are five hundred muscles in the body.

3. Muscles are composed of many small threads called muscular fibres.

4. Many of the muscles are joined to the bones by strong white cords called tendons.

5. Muscular fibres can contract so as to lessen their length. It is in this way that the muscles perform their work.

6. All bodily motions are due to the action of the muscles.

7. Most of the muscles act only when we wish them to do so. Some muscles, however, act when it is necessary for them to do so, whether we will that they should act or not, and when we are asleep as well as when we are awake.



CHAPTER XXI.

HOW TO KEEP THE MUSCLES HEALTHY.

1. How to Make the Muscles Strong.—With which hand can you lift the more? with the right hand or with the left? Why do you think you can lift more with the right hand than with the left? A blacksmith swings a heavy hammer with his right arm, and that arm becomes very large and strong. If we wish our muscles to grow large and strong, so that our bodies will be healthy and vigorous, we must take plenty of exercise.

2. Effects of Idleness.—If a boy should carry one hand in his pocket all the time, and use only the other hand and arm, the idle arm would become small and weak, while the other would grow large and strong. Any part of the body which is not used will after a time become weak. Little boys and girls who do not take plenty of exercise are likely to be pale and puny. It is important that we should take the proper amount of exercise every day, just as we take our food and drink every day.

3. Healthful Exercise.—Some kinds of play, and almost all kinds of work which children have to do, are good ways of taking exercise. A very good kind of exercise for little boys and girls is that found in running errands or doing chores about the house.

4. Food and Strength.—A great part of our food goes to nourish the muscles. Some foods make us strong, while others do not. Plain foods, such as bread, meat, potatoes, and milk, are good for the muscles; but cakes and pies, and things which are not food, such as mustard, pepper, and spices, do not give us strength, and are likely to do us harm.

5. Over-Exertion.—We ought not to exert ourselves too much in lifting heavy weights, or trying to do things which are too hard for us. Sometimes the muscles are permanently injured in this way.

6. The Clothing.—We ought not to wear our clothing so tight as to press hard upon any part of the body. If we do, it will cause the muscles of that part to become weak. If the clothing is worn tight about the waist, great mischief is often done. The lungs cannot expand properly, the stomach and liver are pressed out of shape, and the internal organs are crowded out of their proper places.

7. Tight Shoes.—People are often made very lame from wearing tight shoes. Their muscles cannot act properly, and their feet grow out of shape.

8. In China, it is fashionable for rich ladies to have small feet, and they tie them up in cloths so that they cannot grow. The foot is squeezed out of shape. Here is a picture of a foot which has been treated in this way. It does not look much like a human foot, does it? A woman who has such feet finds it so difficult to walk that she has to be carried about much of the time. Do you not think it is very wrong and foolish to treat the feet so badly? You will say, "Yes;" but the Chinese woman thinks it is a great deal worse to lace the clothing tight about the body so as to make the waist small.



9. Effects of Alcohol upon the Muscles.—When an intemperate man takes a glass of strong drink, it makes him feel strong; but when he tries to lift, or to do any kind of hard work, he cannot lift so much nor work so hard as he could have done without the liquor. This is because alcohol poisons the muscles and makes them weak.

10. Effects of Drunkenness.—When a man has become addicted to strong drink, his muscles become partly paralyzed, so that he cannot walk as steadily or speak as readily or as clearly as before. His fingers are clumsy, and his movements uncertain. If he is an artist or a jeweller, he cannot do as fine work as when he is sober. When a man gets very drunk, he is for a time completely paralyzed, so that he cannot walk or move, and seems almost like a dead man.

11. If you had a good horse that had carried you a long way in a carriage, and you wanted to travel farther, what would you do if the horse were so tired that he kept stopping in the road? Would you let him rest and give him some water to drink and some nice hay and oats to eat, or would you strike him hard with a whip to make him go faster? If you should whip him he would act as though he were not tired at all, but do you think the whip would make him strong, as rest and hay and oats would?

12. When a tired man takes alcohol, it acts like a whip; it makes every part of the body work faster and harder than it ought to work, and thus wastes the man's strength and makes him weaker, although for a little while his nerves are made stupid, so that he does not know that he is tired and ought to rest.

13. When you grow up to be men and women you will want to have strong muscles. So you must be careful not to give alcohol a chance to injure them. If you never taste it in any form you will be sure to suffer no harm from it.

14. Effects of Tobacco on the Muscles.—Boys who smoke cigars or cigarettes, or who chew tobacco, are not likely to grow up to be strong and healthy men. They do not have plump and rosy cheeks and strong muscles like other boys.

15. The evil effect of tobacco upon boys is now so well known that in many countries and in some states of this country laws have been made which do not allow alcohol or tobacco to be sold or given to boys. In Switzerland, if a boy is found smoking upon the streets, he is arrested just as though he had been caught stealing. And is not this really what a boy does when he smokes? He robs his constitution of its vigor, and allows tobacco to steal away from him the strength he will need when he becomes a man.

16. Tea and Coffee.—Strong tea and coffee, while by no means so bad as alcohol and tobacco, may make us weak and sick. A person who drinks strong tea or coffee feels less tired while at work than if he had not taken it, but he is more tired afterwards. So you see that tea and coffee are also whips, small whips we might call them, and yet they really act in the same way as do other narcotics and stimulants. They make a person feel stronger than he really is, and thus he is led to use more strength than he can afford to do.

SUMMARY.

1. We must use the muscles to make them grow large and strong.

2. Exercise should be taken regularly.

3. Exercise makes the muscles strong, the body beautiful, the lungs active, the heart vigorous, and the whole body healthy.

4. Things we ought not to do: To run or play hard just before or after eating; to strain our muscles by lifting too heavy weights; to exercise so violently as to get out of breath; to lie, sit, stand, or walk in a cramped position, or awkward manner; to wear the clothing so tight as to press hard upon the muscles.

5. Good food is necessary to make the muscles strong and healthy.

6. Alcohol makes the muscles weak, although at first it makes us feel stronger.

7. A boy who uses tobacco will not grow as strong and well as one who does not.

8. The use of strong tea and coffee may injure the muscles.



CHAPTER XXII.

HOW WE FEEL AND THINK.

1. How we Think.—With what part of the body do we think? You will at once say that we think with the head; but we do not think with the whole head. Some parts of the head we use for other purposes, as the mouth to eat and speak with, and the nose to smell and breathe with. The part we think with is inside of the skull, safely placed in a little room at the top and back part of the head. Do you remember the name of this organ which fills the hollow place inside of the skull? We learned some time ago that it is called the brain. It is with the brain that we study and remember and reason. So the brain is one of the most important organs in our body, and we must try to learn all we can about it.

2. The Brain.—You cannot see and examine your own brain because it is shut up in the skull; but perhaps you can find the brain of a sheep or a calf at the meat market. The brain of one of these animals looks very nearly like your own.

3. The Large Brain and the Small Brain.—In examining a brain we should notice first of all that there are really two brains, a large brain and a small brain. The large brain is in the top and front of the skull, and the small one lies beneath the back part of the larger one, If we look again we shall see that each brain is divided in the middle into a right and a left half. Each half is, in fact, a complete brain, so that we really have two pairs of brains.



4. Brain Cells.—The brain is a curious organ of a grayish color outside and white inside. It is soft, almost like jelly, and this is why it is placed so carefully in a strong, bony box. If we should put a little piece of the brain under a microscope, we should find that it is made up of a great number of very small objects called nerve or brain cells. In the illustration you can see some of these brain cells.



5. The Nerves.—Each cell has one or more branches. Some of the branches are joined to the branches of other cells so as to unite the cells together, just as children take hold of one another's hands. Other branches are drawn out very long.

6. The long branches are such slender threads that a great number of them together would not be as large as a fine silk thread. A great many of these fine nerve threads are bound up in little bundles which look like white cords. These are called nerves.

7. The nerves branch out from the brain through openings in the skull, and go to every part of the body. Every little muscle fibre, the heart, the stomach, the lungs, the liver, even the bones—all have nerves coming to them from the brain. So you see that the brain is not wholly shut up in the skull, because its cells have slender branches running into all parts of the body; and thus the brain itself is really in every part of the body, though we usually speak of it as being entirely in the skull.

8. The Spinal Cord.—There are a number of small holes in the skull through which the nerves pass out, but most of the nerves are bound up in one large bundle and pass out through an opening at the back part of the skull and runs downward through a long canal in the backbone. This bundle of nerves forms the spinal cord. The spinal cord contains cells also, like those of the brain. It is really a continuation of the brain down through the backbone.



9. Nerves from the Spinal Cord.—The spinal cord gives off branches of nerves which go to the arms, the chest, the legs, and other parts. One of the branches which goes to the hand runs along the back side of the arm, passing over the elbow. If we happen to strike the elbow against some sharp object, we sometimes hit this nerve. When we do so, the under side of the arm and the little finger feel very numb and strange. This is why you call this part of the elbow the "funny" or "crazy bone." The cells of the spinal cord also send out branches to the body and to other cells in the brain.

10. How we Feel.—If we cut or burn ourselves we suffer pain. Can you tell why it hurts us to prick the flesh with a pin, or to pinch or burn or bruise it? It is because the flesh contains a great many nerve-branches from the brain. When we hurt the skin or the flesh, in any way, these nerves are injured. There are so many of these little nerves in the flesh and skin that we cannot put the finest needle into the flesh without hurting some of them.

11. The Use of Pain.—It is not pleasant for us to have pain, but if the nerves gave us no pain when we are hurt we might get our limbs burned or frozen and know nothing about it until too late to save them.

12. Nerves of Feeling.—We have different kinds of nerves of feeling. Those we have learned about feel pain. Others feel objects. If you take a marble or a pencil in the hand you know what it is by the feeling of the object. This kind of feeling is called the sense of touch.

13. There are other nerves of feeling by means of which we are able to hear, see, taste, and smell, of which we shall learn in another lesson. Besides these we have nerves which tell us whether objects are cold or hot, and heavy or light. Nerves of feeling also tell us when we are hungry, or thirsty, or tired, and when we need more air to breathe.

14. Nerves of Work.—There are other nerves which are made just like the nerves of feeling, but which do not feel. These nerves have a very different use. They come from cells in the brain which have charge of the different kinds of work done in the body, and they send their branches to the parts which do the work; hence we call them nerves of work.

15. One set of cells sends nerves to the heart, and these make it go fast or slow as is necessary. Another sends nerves to the liver, stomach, and other digestive organs, and causes them to do their part in the digestion of the food. Other cells send branches to the muscles and make them act when we wish them to do so. Thus you see how very useful the brain and nerves are. They keep all the different parts of the body working together in harmony, just like a well-trained army, or a great number of workmen building a block of houses. Without the brain and nerves the body would be just like an army without a commander, or a lot of workmen without an overseer.

16. How we Use the Nerves.—If you happen to touch your hand to a hot stove, what takes place? You will say that your arm pulls the hand away. Do you know why? Let us see. The nerves of feeling in the hand tell the nerve cells in the brain from which they come that the hand is being burned. The cells which feel cannot do anything for the hand, but some of their branches run over to another part of the brain, which sends nerves down to the muscles of the arm. These cells, through their nerve branches, cause the muscles to contract. The cells of feeling ask the cells which have charge of the muscles to make the muscles of the arm pull the hand away, which they do very quickly.

17. So you see the nerves are very much like telegraph or telephone wires. By means of them the brain finds out all about what is happening in the body, and sends out its orders to the various organs, which may be called its servants.

18. An Experiment.—A man once tried an experiment which seemed very cruel. He took a dove and cut open its skull and took out its large brain. What do you think the effect was? The dove did not die at once, as you would expect. It lived for some time, but it did not know anything. It did not know when it was hungry, and would not eat or drink unless the food or water was placed in its mouth. If a man gets a blow on his head, so hard as to break his skull, the large brain is often hurt so badly that its cells cannot work, and so the man is in the same condition as the poor dove. He does not know anything. He cannot think or talk, and lies as though he were asleep.

19. By these and many other facts we know that the large brain is the part with which we remember, think, and reason. It is the seat of the mind. We go to sleep because the large brain is tired and cannot work any longer. We stop thinking when we are sound asleep, but sometimes we do not sleep soundly, and then the large brain works a little and we dream.

20. What the Little Brain Does.—The little brain[B] thinks too, but it does not do the same kind of thinking as the large brain. We may use our arms and legs and many other parts when we wish to do so; and if we do not care to use them we may allow them to remain quiet. This is not the case with some other organs. It is necessary, for example, that the heart, the lungs, and many other organs of the body should keep at work all the time. If the large brain had to attend to all of these different kinds of work besides thinking about what we see, hear, and read, and other things which we do, it would have too much work to do, and would not be able to do it all well. Besides, the large brain sometimes falls asleep. So the large brain lets the little brain do the kinds of work which have to be attended to all the time, and the little brain keeps steadily at work when we are asleep as well as when we are awake.

21. What the Spinal Cord Does.—If you tickle a person's foot when he is asleep, he will pull it up just as he would if he were awake, only not quite so quickly. What do you suppose makes the muscles of the leg contract when the brain is asleep and does not know that the foot is being tickled? And here is another curious fact. When you were coming to school this morning you did not have to think about every step you took. Perhaps you were talking or looking over your lessons; but your legs walked right along all the time, and without your thinking about them. Can you tell how?

22. It would be too much trouble for the large brain to stop to think every time we step, and the little brain has work enough to do in taking care of the heart and lungs and other organs, without keeping watch of the feet when we are asleep, so as to pull them up if some mischievous person tickles them. So Nature puts a few nerve cells in the spinal cord which can do a certain easy kind of thinking. When we do things over and over a great many times, these cells, after a time, learn to do them without the help of the large brain. This is the way a piano-player becomes so expert. He does not have to think all the time where each finger is to go. After the tunes have been played a great many times, the spinal cord knows them so well that it makes the hands play them almost without any effort of the large brain.

SUMMARY.

1. The part of the body with which we think is the brain.

2. The brain is found filling the hollow place in the skull.

3. There are two brains, the large brain and the small brain.

4. Each brain is divided into two equal and complete halves, thus making two pairs of brains.

5. The brain is largely made up of very small objects called nerve or brain cells.

6. The nerve cells send out very fine branches which form the nerves.

7. The nerve branches or fibres run to every part of the body. They pass out from the brain to the rest of the body through a number of openings in the skull.

8. Most of the nerve branches pass out through a large opening at the back of the skull, in one large bundle called the spinal cord.

9. The spinal cord runs down through a canal in the backbone, and all along gives off branches to the various parts of the body.

10. It gives us pain to prick or hurt the flesh in any way, because when we do so we injure some of the little nerve branches of the brain cells.

11. When we suffer, we really feel a pain in the brain. We know this because if a nerve is cut in two, we may hurt the part to which it goes without giving any pain.

12. We have different kinds of nerves of feeling.

13. There are other nerves besides those of feeling. These are nerves of work.

14. The nerves of work have charge of the heart, the lungs, the muscles, the liver, the stomach, and every part of the body which can work or act.

15. The brain and nerves control the body and make all the different parts work together in harmony, just as a general controls an army.

16. The brain uses the nerves very much as a man uses the telephone or telegraph wires.

17. With the large brain we remember, think, and reason.

18. The little brain does the simple kind of thinking, by means of which the heart, lungs, and other vital organs are kept at work even when we are asleep.

19. The spinal cord does a still more simple kind of work. It enables us to walk and to do other familiar acts without using the large brain to think every moment just what we are doing.



CHAPTER XXIII.

HOW TO KEEP THE BRAIN AND NERVES HEALTHY.

1. Uses of the Brain.—What do you think a boy or girl would be good for without any brain or nerves? Such a boy or girl could not see, hear, feel, talk, run about, or play, and would not know any more than a cabbage or a potato knows. If the brain or nerves are sick, they cannot work well, and so are not worth as much as when they are healthy.

2. The Brain Sympathizes with Other Organs.—Did you ever have a headache? Did you feel happy and good-natured when your head ached hard, and could you study and play as well as when you are well? It is very important that we should keep our brain and nerves healthy, and to do this we must take good care of the stomach and all other organs, because the brain sympathizes with them when they are sick.

3. We must have Pure Air.—How do you feel when the school-room is too warm and close? Do you not feel dull and sleepy and so stupid that you can hardly study? This is because the brain needs good, pure blood to enable it to work well. So we must always be careful to have plenty of pure air to breathe.

4. We should Exercise the Brain.—What do we do when we want to strengthen our muscles? We make them work hard every day, do we not? The exercise makes them grow large and strong. It is just the same with our brains. If we study hard and learn our lessons well, then our brains grow strong, and study becomes easy. But if we only half study, and do not learn our lessons perfectly, then the study does not do our brains very much good.

5. We should Take Muscular Exercise.—When you get tired of study, an hour's play, or exercise of some sort, rests you and makes you feel brighter, so that you can learn more easily. This is because exercise is necessary to make the blood circulate well. It will then carry out the worn-out particles and supply the brain and nerves with fresh, pure blood. So the same exercise which makes our muscles strong makes our brains healthier also.

6. We should be Careful of our Diet.—We ought to eat plenty of good, simple food, such as milk, fruits, grains, and vegetables. It is not well for children to eat freely of meat, as it is very stimulating and likely to excite the brain and make the nerves irritable. Mustard, pepper, and all hot sauces and spices have a tendency to injure the brain and nerves.

7. We should Allow the Brain to Rest at the Proper Time.—When we are tired and sleepy we cannot think well, and cannot remember what we learn if we try to study. If we have plenty of sleep, free from bad or exciting dreams, we awake in the morning rested and refreshed, because while we have been asleep Nature has put the brain and nerves in good repair for us. We ought not to stay up late at night. We should not eat late or hearty suppers, as this will prevent our sleeping well.

8. We Ought Not to Allow Ourselves to Become Angry.—When a person flies into a passion he does his brain and nerves great harm. It is really dangerous to get angry. Persons have dropped dead instantly in a fit of anger.

9. We should Shun Bad Habits.—Bad habits are very hard to give up, and hence we should be careful to avoid them. When a child learns to swear, or to use slang phrases, the brain after a while will make him swear or use bad words before he thinks. In a similar manner other bad habits are acquired.

SUMMARY.

1. A person without a brain or nerves would be of no more account than a vegetable.

2. When the brain or nerves are sick they cannot perform their duties properly.

3. To keep the brain and nerves in good health, we must take good care of the stomach and all other important organs of the body.

4. There are many things which we may do to keep the brain and nerves strong and well.

5. The brain needs pure blood, and so we must be careful to breathe pure air.

6. The brain gets strength by exercise, just as the muscles do. Hence, study is healthful, and makes the brain strong.

7. A good memory is very necessary, but we should not try to remember everything.

8. It is very important that we learn how to observe things closely.

9. Exercise in the open air rests and clears the brain by helping the blood to circulate.

10. Plenty of wholesome and simple food is necessary to keep the brain and nerves in good health. Spices, condiments, and rich foods in general are stimulating and harmful.

11. Plenty of sleep is needed to rest the brain and nerves.

12. It is dangerous as well as wicked to become very angry.

13. We should be careful to avoid forming bad habits of any sort, as they are hard to break, and often adhere to one through life.



CHAPTER XXIV.

BAD EFFECTS OF ALCOHOL UPON THE BRAIN AND NERVES.

1. Drunkenness.—Did you ever see a man who was drunk? If you live in a city it is very likely that you have. How did the drunken man behave? Perhaps he was noisy and silly. Perhaps he was angry and tried to pick a quarrel with some one.

2. What made the man drunk? You say whiskey, but it may have been wine, or beer, or hard cider that he drank. Anything that contains alcohol will make a man drunk, for it is the alcohol which does all the mischief.

3. The Whiskey Flush.—You can almost always tell when a man has been drinking, even when he has not taken enough to make him drunk. You know by his flushed face and red eyes. When a man's face blushes from the use of alcohol, his whole body blushes at the same time. His muscles, his lungs, and his liver blush; his brain and spinal cord blush also.

4. When a man has taken just enough alcohol to make his face blush a little, the extra amount of blood in the brain makes him think and talk more lively, and he is very jolly and gay. This makes many people think that alcohol does them good. But if we notice what a man says when he is excited by alcohol, we shall find that his remarks are often silly and reckless. He says very unwise and foolish things, for which he feels sorry when he becomes sober.

5. Alcohol Paralyzes.—How does a drunken man walk? Let us see why he staggers. When a man takes a certain amount of alcohol his small brain and spinal cord become partly paralyzed, so that they cannot do their duty well; and so, when he tries to walk he reels and stumbles along, often falling down, and sometimes hurting himself very much. The fact is that the alcohol has put his spinal cord and small brain to sleep so that he cannot make his legs do what he wants them to do. Now, if still more alcohol is taken the whole brain becomes paralyzed, and then the man is so nearly dead that we say he is "dead drunk." It is exceedingly dangerous to become dead drunk, as the brain may be so completely paralyzed that it will not recover.

6. A small amount of alcohol does not make a man dead drunk, but it poisons and paralyzes his brain and nerves just according to the quantity he takes.

7. If a person holds a little alcohol in his mouth for a few moments, the tongue and cheeks feel numb. This is because the alcohol paralyzes them so that they cannot feel or taste. When taken into the stomach it has much the same kind of effect upon the nerves of the whole body.

8. Alcohol a Deceiver.—A hungry man takes a drink of whiskey and benumbs the nerves of his stomach so that he does not feel hungry. Alcohol puts to sleep the sentinels which Nature has set in the body to warn us of danger. A man who is cold takes alcohol and feels warm, though he is really colder. He lies down in his false comfort and freezes to death. A tired man takes his glass of grog and feels rested and strong, though he is really weaker than before. A poor man gets drunk and feels so rich that he spends what little money he has. The alcohol paralyzes his judgment and steals away his good sense. Thus alcohol is always a deceiver.

9. Delirium Tremens. (De-lir'-i-um Tre'-mens.)—When a man takes strong liquors regularly he very soon injures his brain and nerves so that they do not get quiet, as they should, at night, and he does not sleep well. He has frightful dreams. He sees all sorts of wild animals and horrid shapes in his dreams. Perhaps you have sometimes had such dreams from eating late suppers or indigestible food.

10. Did you ever have a dream when you were awake? If a man drinks a great deal he is likely to have a terrible disease known as delirium tremens, in which he sees the same frightful things when he is wide awake that he dreams about when he is asleep. This is one of the terrible effects of alcohol upon the brain and nerves.

11. Alcohol Paralysis.—You have seen how a drunken man staggers when he walks. Did you ever see a man who walked just as though he were drunk when he was really sober? This is because a part of the brain or spinal cord has been permanently injured or paralyzed. Alcohol is not the only cause of this disease, and so you must not think every person who staggers is or has been a drunkard; but alcohol is a very frequent cause of paralysis.

12. Effects of Alcohol upon the Mind and Character.—When a man is under the influence of alcohol is his character good or bad? Is a man likely to be good, or to be bad, when he is drunk or excited by drink? Most men behave badly when they are drunk, and after they have been drunk a great many times they often behave badly all the time. A great many of the men who are shut up in prisons would not have been sent there if they had never learned to drink.

13. A Legacy.—Do you know what a legacy is? If your father should die and leave to you a fine house or farm, or money in the bank, or books, or horses, or any other kind of property to have for your own, it would be a legacy. When a person gets anything in this way from a parent we say that he inherits it.

14. We inherit a great many things besides houses and lands and other kinds of property. For instance, perhaps you remember hearing some one say that you have eyes and hair the same color as your mother's, and that your nose and chin are like your father's. So you have inherited the color of your hair and eyes from your mother and the shape of your chin and nose from your father.

15. The Alcohol Legacy.—The inside of a boy's head is just as much like his parents' as the outside of it. In other words, we inherit our brains just as we do our faces. So, if a man spoils his brain with alcohol and gets an alcohol appetite, his children will be likely to have unhealthy brains and an appetite for alcohol also, and may become drunkards. Is not that a dreadful kind of legacy to inherit?

16. A child that has no mind is called an idiot. Such a child cannot talk, or read, or sing, and does not know enough to take proper care of itself. This is one of the bad legacies which drunken parents sometimes leave to their children.

17. Effects of Tobacco on the Brain and Nerves.—The effects of tobacco upon the brain and nerves are much the same as those of alcohol. Tobacco, like alcohol, is a narcotic. It benumbs and paralyzes the nerves, and it is by this means that it obtains such an influence over those who use it.

18. The hand of a man or boy who uses tobacco often becomes so unsteady that he can scarcely write. Do you know what makes it so unsteady? It is because the cells which send nerves to the muscles of the hand are diseased. When a person has a trembling hand you say he is nervous. If you feel his pulse you will find that it does not beat steadily and regularly as it ought to do. The heart is nervous and trembles just the same as the muscles do. This shows that the tobacco has poisoned the cells in the brain which regulate the heart.

19. Wise physicians will tell you that one reason why tobacco is bad for boys is that it hurts their brains so that they cannot learn well, and do not become as useful and successful men as they might be.

20. Students in the naval and military schools of this country are not allowed to use tobacco on account of its bad effects upon the mind. In France the use of tobacco is forbidden to all students in the public schools.

21. Tobacco Leads to Vice.—Boys who use tobacco are more liable to get into company with boys who have other bad habits, and so are apt to become bad in many other ways. The use of tobacco often makes men want strong drink, and thus leads to drunkenness. If you wish to grow up with a steady hand, a strong heart, and a good character you will never touch tobacco.

22. Effects of Tea and Coffee on the Nerves.—People who use strong tea and coffee are often inclined to be nervous. This shows that strong tea and coffee, like alcohol and tobacco, are very injurious to the nerves.

23. Opium, Chloral, etc.—There are several drugs which are given by physicians to relieve pain or to produce sleep. They are sometimes helpful, but their use is very dangerous. Opium and chloral belong to this class of medicines. The danger is that, after a person has used the medicine a little while, he will continue to use it. If a person takes a poisonous drug every time he has a little pain, he will soon form the habit of using it, and may never break it off. There are many thousands of people who use opium all the time, and they are very much injured by it in mind and body. The mind becomes dull and stupid and the body weak and feeble. No medicine of this sort should ever be taken unless prescribed by a physician.

SUMMARY.

1. In order to be well and useful we must keep the brain and nerves healthy.

2. To keep the brain healthy we need plenty of pure air to breathe; proper exercise of the brain by study; sufficient exercise of the muscles in play and work; plenty of good food to make pure blood; a proper amount of rest and sleep.

3. There are several things we ought not to do. We should not read or study too much. We should not allow ourselves to become excited or angry. We should avoid learning bad habits.

4. Alcohol paralyzes the brain and nerves.

5. Alcohol deceives a person who takes it by making him feel strong when he is weak; warm when he is cold; rich when he is poor; well when he is sick.

6. Alcohol makes men wicked. Most men who commit crimes are men who use liquor.

7. The effects of tobacco upon the brain and nerves are much the same as those of alcohol. Tobacco is very injurious to the mind.

8. Tobacco-using often leads boys to drunkenness and other vices.

9. The use of opium and chloral produces even worse effects than the use of alcohol or tobacco.



CHAPTER XXV.

HOW WE HEAR, SEE, SMELL, TASTE, AND FEEL.

1. The Senses.—We have five senses—hearing, seeing, smelling, tasting, and feeling. These are called special senses because they are very different from each other. They also differ from the general sense of feeling by means of which we feel pain when any part is hurt.

2. Organs of the Special Senses.—Each of the special senses has a special set of nerves and also special cells in the brain which have charge of them. We say that we see with our eyes, hear with our ears, feel with our fingers, etc.; but, really, we see, hear, taste, and smell in the brain just as we feel in the brain. The eyes, ears, nose, and other organs of the special senses are the instruments by means of which the brain sees, hears, smells, etc.

3. Sound and the Vibrations which it Causes.—All sounds are made by jars or vibrations of objects. Sounds cause objects to vibrate or tremble. A loud sound sometimes jars a whole house, while other sounds are so gentle and soft that we cannot feel them in the same way that we feel loud sounds. But Nature has made for us an ingenious organ by means of which we can feel these very fine vibrations as well as loud ones. We call this organ the ear.

4. The Ear.—The part of the ear which we can see is shaped somewhat like a trumpet. The small opening near the middle of the ear leads into a canal or tube which extends into the head about an inch. At the inner end there is a curious little chamber. This is called the drum of the ear, because between it and the canal of the ear there is stretched a thin membrane like the head of a drum. The ear-drum is also called the middle ear.



5. Bones of the Ear.—Within the drum of the ear there are three curious little bones which are joined together so as to make a complete chain, reaching from the drum-head to the other side of the drum. The last bone fits into a little hole which leads into another curious chamber. This chamber, which is called the inner ear, is filled with fluid, and in this fluid the nerve of hearing is spread out. A part of the inner ear looks very much like a snail shell.



6. How we Hear.—Scratch with a pin upon one end of a long wooden pole. Have some one listen with the ear placed close against the other end of the pole. He will tell you that he hears the scratching of the pin very plainly. This is because the scratching jars the ear and especially the drum-head, which vibrates just as the head of a drum does when it is beaten with a drum-stick. When the drum-head vibrates it moves the bones of the ear, and these carry the vibration to the nerves of hearing in the inner chamber. We hear all sounds in the same way, only most sounds come to the ear through the air.

The snail-shell of the inner part of the ear hears musical sounds. The rest of the inner ear hears ordinary sounds or noises.

7. How to Keep the Ears Healthy.—The ears are very delicate organs and must be carefully treated. The following things about the care of the ears should never be forgotten:

(1.) Never use a pin, toothpick, or any other sharp instrument to clean out the ear. There is great danger that the drum-head will be torn, and thus the hearing will be injured. Neither is it ever necessary to use an ear-spoon to remove the wax. Working at the ear causes more wax to form.

(2.) Do not allow cold water to enter the ear or a cold wind to blow directly into it.

(3.) If anything accidentally gets into the ear, do not work at it, but hold the head over to one side while water is made to run in from a syringe. If an insect has gone into the ear, pour in a little oil. This will kill the insect or make it come out.

(4.) Never shout into another person's ear. The ear may be greatly injured in this way.

(5.) Boxing or pulling the ears is likely to produce deafness, and ought never to be done.

8. The Eye.—The eye is one of the most wonderful organs in the whole body. It enables us to know what is going on at some distance from us, and to enjoy many beautiful things which our sense of hearing and other senses can tell us nothing about. It also enables us to read. Let us learn how this wonderful organ is made.

9. The Eyeball.—Looking at the eye, we see first a round part which rolls in different directions. This is the eyeball. We see only the front side of the eyeball as it fits into a hollow in the skull. Being thus in a safe place, it is not likely to get hurt.



The eyeball is mostly filled with a clear substance very much like jelly. It is so clear that the light can shine through it just as easily as it can shine through water.

10. The Pupil.—If you look sharply at the eyeball you will see a small black hole just in the centre. This is a little window which lets the light into the inside of the eyeball. We call this the pupil. Just around the pupil is a colored ring which gives the eye its color. We say a person has blue or brown or gray eyes according as this ring is blue or brown or gray. This colored ring is a kind of curtain for the window of the eye.

11. If you observe the pupil closely, you will see that it is sometimes larger and sometimes smaller. If you look at the light the pupil is small; if you turn away from the light the pupil grows larger at once. This is because the curtain closes when in a bright light and opens in the darkness. It does this of itself without our thinking about it. In this way the eye is protected from too strong a light, which would do it great harm.

12. If you look a little sidewise at the eyeball, you will see that the curtain has something in front of it which is clear as glass. It is about the shape of a watch crystal, only very much smaller. This is to the eye what the glass is to the windows of a house. It closes the opening in the front of the eyeball and yet lets the light shine in.

13. The White of the Eye.—The white of the eye is a tough, firm membrane which encloses the eyeball and keeps it in a round shape.

14. The Lens.—Do you know what a lens is? Perhaps you do not know it by this name, but you are familiar with the spectacles which people sometimes wear to help their eyes. The glasses in the spectacle frames are called lenses. Well, there is something in the eye almost exactly like one of these lenses, only smaller. It is also called a lens. If some one will get the eye of an ox for you, you can cut it open and find this part. The lens is placed in the eyeball just behind the pupil. (See picture.)



15. The Nerves of Sight.—But a person might have an eyeball with all the parts we have learned about and yet not be able to see. Can you tell what more is needed? There must be a nerve. This nerve comes from some little nerve cells in the brain and enters the eyeball at the back of the eye; there it is spread out on the inside of the black lining of the white of the eye.

16. The Eyelids.—Now we know all that it is necessary for us to learn about the eyeball, so let us notice some other parts about the eye. First there are the eyelids. They are little folds of skin fringed with hairs, which we can shut up so as to cover the eyeball and keep out the light when we want to sleep or when we are in danger of getting dust or smoke into the eye. The hairs placed along the edge of the lids help to keep the dust out when the eyes are open.

17. The Eyebrows.—The row of hairs placed above the eye is called the eyebrow. Like the eyelids, the eyebrows catch some substances which might fall into the eye, and they also serve to turn off the perspiration and keep it out of the eyes.

18. The Tear Gland.—Do you know where the tears come from? There is a little gland snugly placed away in the socket of the eye just above the eyeball, which makes tears in the same way that the salivary glands make saliva. It is called the tear gland. The gland usually makes just enough tears to keep the eye moist. There are times when it makes more than enough, as when something gets into the eye, or when we suffer pain or feel unhappy. Then the tears are carried off by means of a little tube which runs down into the nose from the inner corner of the eye. When the tears are formed so fast that they cannot all get away through this tube, they pass over the edge of the lower eyelid and flow down the cheek.

19. Muscles of the Eyes.—By means of little muscles which are fastened to the eyeball, we are able to turn the eye in almost every direction.

20. How we See.—Now we want to know how we see with the eye. This is not very easy to understand, but we can learn something about it. Let us make a little experiment. Here is a glass lens. If we hold it before a window and place a piece of smooth white paper behind it, we can see a picture of the houses and trees and fences, and other things out-of-doors. The picture made by the lens looks exactly like the view out-of-doors, except that it is upside down. This is one of the curious things that a lens does. The lens of the eye acts just like a glass lens. It makes a picture of everything we see, upon the ends of the nerves of sight which are spread out at the back of the eyeball. The nerves of sight tell their nerves in the brain about the picture, just as the nerves of feeling tell their cells when they are touched with a pin; and this is how we see.

21. Did you ever look through a spyglass or an opera-glass? If so, you know you must make the tube longer or shorter according as you look at things near by or far away. The eye also has to be changed a little when we look from near to distant objects. Look out of the window at a tree a long way off. Now place a lead pencil between the eyes and the tree. You can scarcely see the pencil while you look sharply at the tree, and if you look at the pencil you cannot see the tree distinctly.

22. There is a little muscle in the eye which makes the change needed to enable us to see objects close by as well as those which are farther away. When people grow old the little muscles cannot do this so well, and hence old people have to put on glasses to see objects near by, as in reading. Children should not try to wear old persons' glasses, as this is likely to injure their eyes.

23. How to Keep the Eyes Healthy.—(1.) Never continue the use of the eyes at fine work, such as reading or fancy-work, after they have become very tired.

(2.) Do not try to read or to use the eyes with a poor light—in the twilight, for instance, before the gas or lamps are lighted.

(3.) In reading or studying, do not sit with the light from either a lamp or a window shining directly upon the face. Have the light come from behind and shine over the left shoulder if possible.

(4.) Never expose the eyes to a sudden, bright light by looking at the sun or at a lamp on first awaking in the morning, or by passing quickly from a dark room into a lighted one.

(5.) Do not read when lying down, or when riding on a street car or railway train.

(6.) If any object gets into the eye have it removed as soon as possible.

(7.) A great many persons hurt their eyes by using various kinds of eye-washes. Never use anything of this kind unless told to do so by a good physician.

24. How we Smell.—If we wish to smell anything very strongly, we sniff or suddenly draw the air up through the nose. We do this to bring more air to the nerves of smell, which are placed at the upper part of the inside of the nose.



25. Smelling is a sort of feeling. The nerves of smell are so sensitive that they can discover things in the air which we cannot taste or see. An Indian uses his sense of smell to tell him whether things are good to eat or not. He knows that things which have a pleasant smell are likely to be good for him and not likely to make him sick.

We do not make so much use of the sense of smell as do the savages and many lower animals, and hence we are not able to smell so acutely. Many persons lose the sense of smell altogether, from neglecting colds in the head.

26. How we Taste.—The tongue and the palate have very delicate nerves by means of which we taste. We cannot taste with the whole of the tongue. The very tip of the tongue has only nerves of touch or feeling.

27. The use of the sense of taste is to give us pleasure and to tell us whether different substances are healthful or injurious. Things which are poisonous and likely to make us sick almost always have an unpleasant taste as well as an unpleasant odor. Things which have a pleasant taste are usually harmless.

28. Bad Tastes.—People sometimes learn to like things which have a very unpleasant taste. Pepper, mustard, pepper-sauce, and other hot sauces, alcohol, and tobacco are harmful substances of this sort. When used freely they injure the sense of taste so that it cannot detect and enjoy fine and delicate flavors. These substances, as we have elsewhere learned, also do the stomach harm and injure the nerves and other parts of the body.

29. The Sense of Touch.—If you put your hand upon an object you can tell whether it is hard or soft, smooth or rough, and can learn whether it is round or square, or of some other shape. You are able to do this by means of the nerves of touch, which are found in the skin in all parts of the body. If you wished to know how an object feels, would you touch it with the elbow, or the knee, or the cheek? You will say, No. You would feel of it with the hand, and would touch it with the ends of the fingers. You can feel objects better with the ends of the fingers because there are more nerves of touch in the part of the skin covering the ends of the fingers than in most other parts of the body.

30. The sense of touch is more delicate in the tip of the tongue than in any other part. This is because it is necessary to use the sense of touch in the tongue to assist the sense of taste in finding out whether things are good to eat or not. The sense of touch is also very useful to us in many other ways. We hardly know how useful it really is until we are deprived of some of our other senses, as sight or hearing. In a blind man the sense of touch often becomes surprisingly acute.

31. Effects of Alcohol and Tobacco on the Special Senses.—All the special senses—hearing, seeing, smelling, tasting, feeling—depend upon the brain and nerves. Whatever does harm to the brain and nerves must injure the special senses also. We have learned how alcohol and tobacco, and all other narcotics and stimulants, injure and sometimes destroy the brain cells and their nerve branches, and so we can understand that a person who uses these poisonous substances will, by so doing, injure the delicate organs with which he hears, sees, smells, etc.

32. Persons who use tobacco and strong drink sometimes become blind, because these poisons injure the nerves of sight. The ears are frequently injured by the use of tobacco. Smoking cigarettes and snuff-taking destroy the sense of smell. The poison of the tobacco paralyzes the nerves of taste so that they cannot detect flavors. Tea-tasters and other persons who need to have a delicate sense of taste do not use either alcohol or tobacco.

SUMMARY.

1. We have five special senses—hearing, seeing, smelling, tasting, and feeling.

2. The ear is the organ of hearing, and has three parts, called the external ear, the middle ear, and the inner ear. The inner ear contains the nerve of hearing.

3. The middle ear is separated from the external ear by the drum-head. The drum-head is connected with the inner ear by a chain of bones.

4. Sounds cause the drum-head to vibrate. The ear-bones convey the vibration from the drum-head to the nerve of hearing.

5. To keep the ear healthy we must avoid meddling with it or putting things into it.

6. The eye is the organ of sight. The chief parts of the eye are the eyeball, the socket, and the eyelids.

7. In the eyeball are the pupil, the lens, and the nerve of sight.

8. The eyeball is moved in various directions by six small muscles.

9. The eye is moistened by tears from the tear-gland.

10. When we look at an object the lens of the eye makes a picture on the nerve of sight, at the back part of the eyeball.

11. To keep the eyes healthy we should be careful not to tax them long at a time with fine work, or to use them in a poor light.

12. The nerves of smell are placed in the upper part of the inside of the nose.

13. "Colds" often destroy the sense of smell.

14. The nerves of taste are placed in the tongue and palate.

15. Many things which we think we taste we really do not taste, but smell or feel.

16. Objects which have a pleasant taste are usually healthful, while those which have a bad taste are usually harmful.

17. Pepper, mustard, etc., as well as alcohol and tobacco, have an unpleasant taste, and are not healthful. If we use them we shall injure the nerves of taste as well as other parts of the body.

18. We feel objects by means of the sense of touch.

19. The sense of touch is most acute at the tip of the tongue and the ends of the fingers.



CHAPTER XXVI.

ALCOHOL.

1. As we learned in the early part of our study of this subject, alcohol is produced by fermentation. It is afterwards separated from water and other substances by distillation. We will now learn a few more things about alcohol.

2. Alcohol Burns.—If alcohol is placed in a lamp, it will burn much like kerosene oil. Indeed, it does not need a lamp to help it burn as does oil. If a few drops of alcohol are placed upon a plate, it may be lighted with a match, and will burn with a pale blue flame. Thus you see that alcohol is a sort of burning fluid.

3. The vapor of alcohol will burn also, and under some circumstances it will explode. On this account it is better not to try any experiments with it unless some older person is close by to direct you, so that no harm may be done. Alcohol is really a dangerous substance even though we do not take it as a drink.

4. An Interesting Experiment.—We have told you that all fermented drinks contain alcohol. You will remember that wine, beer, ale, and cider are fermented drinks. We know that these drinks contain alcohol because the chemist can separate the alcohol from the water and other substances, and thus learn just how much alcohol each contains.

5. If we should remove all the alcohol from wine, no one would care to drink it. The same is true of beer and cider. It is very easy to remove the alcohol by the simple process of heating. This is the way the chemist separates it. The heat drives the alcohol off with the steam. If the heating is continued long enough, all the alcohol will be driven off. The Chinaman boils his wine before drinking it. Perhaps this is one reason why Chinamen are so seldom found drunken.

6. By a simple experiment which your parents or your teacher can perform for you, it can be readily proven that different fermented drinks contain alcohol, and also that the alcohol may be driven off by heat. Place a basin half full of water upon the stove where it will soon boil. Put into a glass bottle enough beer or cider so that when the bottle stands up in the basin the liquid in the bottle will be at about the same height as the water in the basin. Now place in the neck of the bottle a closely fitting cork in which there has been inserted a piece of the stem of a clay pipe or a small glass tube. Place the bottle in the basin. Watch carefully until the liquid in the bottle begins to boil. Now apply a lighted match to the end of the pipe-stem or glass tube. Perhaps you will observe nothing at first, but continue placing the match to the pipe-stem, and pretty soon you will notice a little blue flame burning at the end of the stem. It will go out often, but you can light it again. This is proof that alcohol is escaping from the liquid in the bottle. After the liquid has been boiling for some time, the flame goes out, and cannot be re-lighted, because the alcohol has been all driven off.



7. The Alcohol Breath.—You have doubtless heard that a person who is under the influence of liquor may be known by his breath. His breath smells of alcohol. This is because his lungs are trying to remove the alcohol from his blood as fast as possible, so as to prevent injury to the blood corpuscles and the tissues of the body. It is the vapor of alcohol mixed with his breath that causes the odor.

8. You may have heard that sometimes men take such quantities of liquor that the breath becomes strong with the vapor of alcohol and takes fire when a light is brought near the mouth. These stories are probably not true, although it sometimes happens that persons become diseased in such a way that the breath will take fire if it comes in contact with a light. Alcohol may be a cause of this kind of disease.

9. Making Alcohol.—It may be that some of our young readers would like to find out for themselves that alcohol is really made by fermentation. This may be done by an easy experiment. You know that yeast will cause bread to "rise" or ferment. As we have elsewhere learned, a little alcohol is formed in the fermentation of bread, but is driven off by the heat of the oven in baking, so that we do not take any of it into our stomachs when we eat the bread. If we place a little baker's yeast in sweetened water, it will cause it to ferment and produce alcohol. To make alcohol, all we have to do is to place a little yeast and some sweetened water in a bottle and put it away in a warm place for a few hours until it has had time to ferment. You will know when fermentation has taken place by the great number of small bubbles which appear. When the liquid has fermented, you may prove that alcohol is present by means of the same experiment by which you found the alcohol in cider or wine. (See page 160.)

10. Alcohol is made from the sweet juices of fruits by simply allowing them to ferment. Wine, as you know, is fermented grape juice. Cider is fermented apple juice. The strong alcoholic liquor obtained by distilling wine, cider, or any kind of fermented fruit juice, is known as brandy.

11. How Beer is Made.—Beer is made from grain of some sort. The grain is first moistened and kept in a warm place for a few days until it begins to sprout. The young plant needs sugar for its food; and so while the grain is sprouting, the starch in the grain is changed into sugar by a curious kind of digestion. This, as you will remember, is the way in which the saliva acts upon starch. So far no very great harm has been done, only sprouted grain, though very sweet, is not so good to eat as grain which has not sprouted. Nature intends the sugar to be used as food for the little sproutlet; but the brewer wants it for another purpose, and he stops the growth of the plant by drying the grain in a hot room.

12. The next thing the brewer does is to grind the sprouted grain and soak it in water. The water dissolves out the sugar. Next he adds yeast to the sweet liquor and allows it to ferment, thus converting the sugar into alcohol. Potatoes are sometimes treated in a similar way.

13. By distilling beer, a strong liquor known as whiskey is obtained. Sometimes juniper berries are distilled with the beer. The liquor obtained is then called gin. In the West Indies, on the great sugar plantations, large quantities of liquor are made from the skimmings and cleanings of the vessels in which the sweet juice of the sugar-cane is boiled down. These refuse matters are mixed with water and fermented, then distilled. This liquor is called rum.

14. Now you have learned enough about alcohol to know that it is not produced by plants in the same way that food is, but that it is the result of a sort of decay. In making alcohol, good food is destroyed and made into a substance which is not fit for food, and which produces a great amount of sickness and destroys many lives. Do you not think it a pity that such great quantities of good corn and other grains should be wasted in this way when they might be employed for a useful purpose?

15. The Alcohol Family.—Scientists tell us that there are several different kinds of alcohol. Naphtha is a strong-smelling liquid sometimes used by painters to thin their paint and make it dry quickly. It does not have the same odor as alcohol, but it looks and acts very much like it. It will burn as alcohol does. It kills animals and plants. It will make a person drunk if he takes a sufficient quantity of it. Indeed, it is so like alcohol that it really is a kind of alcohol.

16. There are also other kinds of alcohol. Fusel-oil, a deadly poison, is an alcohol. A very small amount of this alcohol will make a person very drunk. Fusel-oil is found in bad whiskey. (All whiskey is bad, but some kinds are worse than others.) This is why such whiskey makes men so furiously drunk. It also causes speedy death in those who use it frequently. There are still other kinds of alcohol, some of which are even worse than fusel-oil. So you see this is a very bad family.

17. Like most other bad families, this alcohol family has many bad relations. You have heard of carbolic acid, a powerful poison. This is one of the relatives of the alcohol family. Creosote is another poisonous substance closely related to alcohol. Ether and chloroform, by which people are made insensible during surgical operations, are also relatives of alcohol. They are, in fact, made from alcohol. These substances, although really useful, are very poisonous and dangerous. Do you not think it will be very wise and prudent for you to have nothing to do with alcohol in any form, even wine, beer, or cider, since it belongs to such a bad family and has so many bad relations?

18. Some persons think that they will suffer no harm if they take only wine or beer, or perhaps hard cider. This is a great mistake. A person may get drunk on any of these drinks if a sufficient amount be taken. Besides, boys who use wine, beer, or cider, rarely fail to become fond of stronger liquors. A great many men who have died drunkards began with cider. Cider begins to ferment within a day or two after it is made, and becomes stronger in alcohol all the time for many months.

19. "Bitters."—There are other liquids not called "drinks" which contain alcohol. "Bitters" usually contain more alcohol than is found in ale or wine, and sometimes more than in the strongest whiskey. "Jamaica ginger" is almost pure alcohol. Hence, it is often as harmful for a person to use these medicines freely as to use alcoholic liquors in any other form.

20. Alcoholic liquors of all kinds are often adulterated. That is, they contain other poisons besides alcohol. In consequence of this, they may become even more harmful than when pure; but this does not make it safe to use even pure liquor. Alcohol is itself more harmful than the other drugs usually added in adulteration. It is important that you should know this, for many people think they will not suffer much harm from the use of alcohol if they are careful to obtain pure liquors.

21. Some Experiments.—How many of you remember what you have learned in previous lessons about the poisonous effects of alcohol? Do people ever die at once from its effects? Only a short time ago a man made a bet that he could take five drinks of whiskey in five seconds. He dropped dead when he had swallowed the fourth glass. No one ever suffered such an effect from taking water or milk or any other good food or drink.

22. A man once made an experiment by mistake. He was carrying some alcohol across a lawn. He accidentally spilled some upon the grass. The next day he found the grass as dead and brown as though it had been scorched by fire.

23. Mr. Darwin, the great naturalist, once made a curious experiment. He took a little plant with three healthy green leaves, and shut it up under a glass jar where there was a tea-spoonful of alcohol. The alcohol was in a dish by itself, so it did not touch the plant; but the vapor of the alcohol mixed with the air in the jar so that the plant had to breathe it. In less than half an hour he took the plant out. Its leaves were faded and somewhat shrivelled. The next morning it appeared to be dead. Do you suppose the odor of milk or meat, or of any good food, would affect a plant like that? Animals shut up with alcohol die in just the same way.

24. A Drunken Plant.—How many of you remember about a curious plant that catches flies? Do you remember its name? What does the Venus's fly-trap do with the flies after it catches them? Do you say that it eats them? Really this is what it does, for it dissolves and absorbs them. In other words, it digests them. This is just what our stomachs do to the food we eat.

25. A few years ago Mr. Darwin thought that he would see what effect alcohol would have upon the digestion of a plant. So he put a fly-catching plant in a jar with some alcohol for just five minutes. The alcohol did not touch the plant, because the jar was only wet with the alcohol on the inside. When he took the plant out, he found that it could not catch flies, and that its digestion was spoiled so that it could not even digest very tender bits of meat which were placed on its leaves. The plant was drunk.

26. Mr. Darwin tried a great many experiments with various poisons, and found that the plants were affected in much the same way by ether and chloroform, and also by nicotine, the poisonous oil of tobacco. Sugar, milk, and other foods had no such effect. This does not look much as though alcohol would help digestion; does it?

27. Effects of Alcohol on Digestion.—Dr. Roberts, a very eminent English scientist, made many experiments, a few years ago, to ascertain positively about the effect of alcohol upon digestion. He concluded that alcohol, even in small doses, delays digestion. This is quite contrary to the belief of very many people, who suppose that wine, cider, or stronger liquors aid digestion. The use of alcohol in the form of beer or other alcoholic drinks is often a cause of serious disease of the stomach and other digestive organs.