Consumption should be recognized early
When people first get consumption, they seldom realize that they are seriously sick. Most of them think they have a bad cold, or are overworked, or that they have been staying too closely in the house. Often they will not even see a doctor until they are so sick that the doctor cannot do much for them.
When you have a slight cough that "hangs on"; when you feel feverish every afternoon; when you are short of breath; when you get tired very easily; when you do not feel like eating anything except candies and cakes—then you should think of consumption. These are not all the signs, but they are enough to make you go at once to a doctor.
A long time ago the doctor would have felt badly if he had been obliged to tell you that you had consumption; but now he knows that if you go to him early in the disease and follow his directions, you will get well.
How consumption is cured: (1) By rest
When the doctor finds that a person has consumption, the first thing he orders is rest. By this he means absoluterest. He does not mean that the patient can go to school or to the office part of the day and rest the remainder of the day. The doctor will want to watch him constantly. Then there comes a time when he must begin to take a little exercise; the doctor tells him just how much exercise to take, and just what form of exercise is best for him.
(2) By fresh air
The consumptive must have plenty of fresh air all the time; he must be out-of-doors as much as possible. You will wonder how the doctor expects him to be out-of-doors when he has been told that he must have absolute rest.Later we will show you how one can practically be out-of-doors and yet at the same time be in bed.
(3) By sunshine
Sunshine will kill the germs of any disease more quickly than almost anything we know of, and a consumptive must have all the sunshine that he can get. Of course it cannot get into the body to kill the germs, but it strengthens the cells of the body so much that they can fight with just that much more energy.
Figs.72 and 73. Living outdoors in cold weather.
Figs.72 and 73. Living outdoors in cold weather.
(4) By nourishing food
Nothing is more important than pure food in building up the body and in making heat and power. In consumption the food that is stored up in the body burns itself up very fast. The consumptive must therefore take not only the food needed to supply the usual demands of the body, but enough to make something extra for the disease to burn up without drawing on the reserve fund stored in the body. In order to do this, he will have to eat a great deal, and what he eats must be of the kind that makes the best building material and the most nourishing material.He cannot tax his stomach by eating things that are not nourishing; all the work his stomach can do must be devoted to the foods he really needs.
The weapons with which we fight consumption are rest, good food, fresh air, and sunshine. These will do more good than all the medicine in the world. Fresh air is not only one of the best things for the cure of consumption, but it is one of the best things for the prevention of consumption. You should always breathe plenty of fresh air night and day, and there is plenty of fresh air to be had if you will take it.
Fig. 74.A window tent. (Invented by Dr. W. E. Walsh.)
Fig. 74.A window tent. (Invented by Dr. W. E. Walsh.)
How to have fresh air at home:
If you have only a single window in your room, try to sleep with your head in the fresh air. It is not always easy to arrange a room in such a way that you can have fresh air without placing your bed in a draft, but even this difficulty can be overcome.
(1) By window tents
There are several devices, called window tents, whichyou can buy. By the use of such a tent, your head will be out-of-doors all the time; yet the draft cannot strike your body, because a part of the tent fits around your neck and cuts off the air from the rest of your body. One of these tents is shown in Figure 74. You do not put your head out of the window; your head is on your pillow just as if the tent were not there. Your bed is placed directly in front of the window and the tent comes down over your pillow, allowing your head practically to be out-of-doors, but keeping the cold air out of the room. Sleeping under a window tent is the next best thing to sleeping out-of-doors.
Fig. 75.A sleeping porch built in a house.
Fig. 75.A sleeping porch built in a house.
(2) By sleeping porches
Many of our modern houses are built with sleeping porches on which one can sleep outdoors summer and winter. Where there is not a special sleeping porch on the house, an ordinary porch may often be made to serve the purpose, or a very inexpensive sleeping porch can be added to the house.
(3) By tent cots
Sometimes people cannot get the use of a porch of any kind. In such cases it may be possible to put up a tent in the yard. If the yard is very small, a tent cot may be used. This is simply a cot with a tent on it, which can be closed up and put away in the daytime and set up again at night. In a large city where the houses have no yards at all, this arrangement canbe used by setting it up on the roof of the house. There is almost always some way of securing fresh air at night if we will only give a little thought to the matter.
Fresh air in schoolrooms
Unfortunately, many of our school buildings are not provided with good ventilating plants. A proper system of ventilation furnishes at least 1200 cubic feet of fresh air per hour for each child in each room.
Fig. 76.An open-air schoolroom for consumptive children.
Fig. 76.An open-air schoolroom for consumptive children.
The necessity for playgrounds
In large cities it is often impossible to find outdoor space in which boys and girls may play during recess. Even this difficulty can be overcome by turning the roof of the school building into a playground, with a high wire netting around it.
Every school yard should be provided with swings, bars, and gymnasium apparatus to encourage the children to take plenty of exercise. Children who live in crowded townsneed exercise during vacation as well as during school days, and the school yards should be open to them at all times. A summer teacher who shows the children the best way to exercise, has work fully as important as that of any other teacher during the school term.
A sound body is more valuable than education itself, but a good education and a sound body together are the best assets any man or woman can have.
Questions.1. State the four things necessary to cure consumption; show the value of each. 2. What is the value of fresh air to every one? 3. How may an abundance of fresh air be secured in the home? 4. In the school?Remember.1. Rest, fresh air, sunshine, and nourishing food are the cures for consumption. 2. All these things can be secured in any climate and by every person. 3.Tuberculosis is a communicable disease.4.Tuberculosis can be prevented.5.Tuberculosis can be cured.
Questions.1. State the four things necessary to cure consumption; show the value of each. 2. What is the value of fresh air to every one? 3. How may an abundance of fresh air be secured in the home? 4. In the school?
Remember.1. Rest, fresh air, sunshine, and nourishing food are the cures for consumption. 2. All these things can be secured in any climate and by every person. 3.Tuberculosis is a communicable disease.4.Tuberculosis can be prevented.5.Tuberculosis can be cured.
BONES AND JOINTSThe framework of the bodyThe framework of the body is composed of bones. There are 206 bones (not including the teeth) in the body. The bones of the body are divided into four classes—long bones, short bones, flat bones, and irregular bones.Construction of bonesRegardless of their shape, all bones are composed in the same way. Every bone has an outer and an inner portion. The outer portion is a dense layer calledcompact bone. The inner portion is more open, and is much weaker; this is calledcancellated bone(fromcancella, a sponge). In the smaller bones, the marrow, which is quite soft, runs through the spongy bone; in the larger long bones, the marrow is distinct and is enclosed by the spongy bone.The periosteumEvery bone is covered by a thick, tough layer, theperiosteum, which has three uses. When the bone is injured by disease or accident, the periosteum makes new bone to fill in and repair the break. It also builds new bone on the surface of the old as long as the body is growing. Finally, the periosteum gives strong and firm attachment to the muscles, which send tendons into it.JointsEvery bone in the body (except the hyoid bone, to which the tongue is attached) is joined with some other bone. Most of them join with two or more bones. In most instances the end of a bone which joins with another is rounded off and made very smooth, so that it can slide easily over the other bone. There are three principal kinds of joints in the body. They are called theball and socketjoint, thehingejoint, and theserratedorsaw-toothjoint.Fig. 77.The skeleton.The ball and socket jointThe ball and socket joint is one that can move freely in all directions. We see it illustrated in the joints of the shoulderand hip. In these joints one of the bones has a deep depression in it, and this depression forms thesocket. The other bone has a rounded head that fits into the depression. We call this rounded head theball.Fig. 78.The structure of a bone.The hinge jointThe hinge joint is illustrated in the knee and elbow joints. These joints can move backward and forward in one plane like a hinge, but they cannot move in a circle like the ball and socket joints. You cannot swing your forearm about on a pivot at the elbow as you can your whole arm, nor will the knee joint bend in every direction as does the joint at the hip.Serrated jointsSerrated joints do not move. The bones having serrated joints are fitted tightly together so that they form practically one bone. We find this kind of joint illustrated in the way the bones of the skull are put together.LigamentsThe joints of the body are not held together by rivets, pins or bolts as are the joints of a machine, but by bands of very tough tissue placed about a joint in such a way as to allow it to move freely, although the bones are all the time held firmly together. These bands are calledligaments. Ligaments are much better than bolts or pegs would be, because they stretch a little, and thus prevent the breaking of the bones when the joint is put under a severe strain.Fig. 79.The muscles.MUSCLES AND TENDONSWhat muscle isThe lean meat of any animal is composed entirely of muscle tissue. It is the function of the muscles to move the body.Fig. 80.The biceps muscle contracted.How the muscles workThe muscles are nearly all attached to the bones. They are just long enough to let the joint straighten out when the muscles are at rest, but when the joint bends the muscle contracts. When a muscle contracts it becomes shorter and thicker. Sometimes it becomes very much thicker in one place. Every boy knows how much thicker the arm muscle (biceps) becomes when he bends his elbow hard. He calls this "showing his muscle."TendonsThere is not room enough on most of the bones for all the muscles to be attached directly to them. Instead of being thus attached directly to the bone, they end in what we calltendons. These tendons are hard and strong, and a very small tendon will lift as much without breaking as quite a large muscle. The muscles are soft and would have to be attached over a large area in order to secure the required strength. The tendons, being so much stronger than the muscles, can be attached to a very small area and yet secure the same amount of power as would result from attaching the muscle itself.The tendons pass directly into the periosteum, the thick, strong covering of the bones. So strong is this attachment that the bone will often break before the tendon will pull loose.THE SKINThe skin as an armorThe entire body is covered with skin, which regulates the heat of the body and acts as an armor against blows and cuts which would otherwise injure the delicate nerves and blood vessels beneath. It also serves to some extent to keep out the germs of disease. The skin appears to be smooth, but if you examine it through a strong magnifying glass you will see that it is divided into little areas. The dividing lines do not run straight, however, and the areas are not square like those you find on a checkerboard.Fig. 81.A section of the skin, highly magnified.Sweat glandsAfter looking at the skin with a strong magnifying glass you will think that you must have seen all its irregularities, but if you will look at it with a powerful microscope you will find out many other things. In the first place you will see many little openings in the skin. These little openings make the ridges which divide the skin into little areas. Some of the openings aresweat glands, and there is always some perspiration coming out of them. When you are very warm you can see, without the aid of the glass, the drops of perspiration as they come out on the surface of the skin. When you are not very warm you cannot see these drops of perspiration, but they are nevertheless coming out all the time. When the perspiration comes so slowly that you cannot see it, it is calledinsensible perspiration.HairThe whole body is covered with hair. You can see the hair on your head and some of the hair on your arms and the backs of your hands, but most of the hair on the body is so fine that you cannot see it without a microscope. Each of the fine hairs on the body has a root that goes through the skin just as the root from each hair on your head goes through it.Sebaceous glandsOpening into the little pockets in which the hairs stand, are glands that secrete a kind of oily material. They are calledsebaceous glandsorfollicles. Sometimes these follicles become stopped up; then the material they secrete becomes thick and cheesy, and the little black points appear on the skin which we callblackheads. The white matter which comes out of these blackheads is merely the secretion of the glands from which the water has been absorbed, leaving the solid or cheesy portion.NailsThere is a part of the skin that we do not usually think of as skin. We mean thenails. The finger nails and the toe nails do not look like the rest of the skin of the body, but they are made of just the same kind of cells. The cells of the nails are flat, dead, and closely packed together. There are no sweat glands, or sebaceous glands, or any hairs in the nails.THE DIGESTIVE SYSTEMThe alimentary canalThe digestive system is the part of our bodies in which the food we eat is so changed that it can be made use of by the little cells in the body. It is composed of a long canal with many parts and enlargements, each part necessary for a certain required work. This canal as a whole is called thealimentary canal.TeethThe mouth does the first part of the work for the digestive system. Here we find the teeth, which are used for grinding the food. The teeth are composed of three parts, thehead(orcrown), theneckand theroot. The head, orcrown, is very hard. Each tooth is hollow, and in the hollow portion there are nerves and blood vessels.The salivary glandsOpening into the mouth are three pairs of glands known assalivary glands. One pair of glands is located just above the angle of the jaw. It is these glands that become swollen when we have mumps. Another pair of glands is placed just inside the jaw bone, near the root of the tongue, and the third pair is located under the tongue. These three pairs of glands secrete the saliva which moistens the food and aids in digesting the starch.Fig. 82.The alimentary canal.The esophagusThe food passes from the mouth; through a passage called theesophagus, or gullet, to thestomach.The stomachThe stomach is one of the enlarged parts of the alimentary canal. Its walls are quite thick, and in these walls are thousands of little glands. These glands secrete a fluid calledgastric juice. When the food enters the stomach it is held there for a long time, and the walls of the stomach squeeze upon it so that the food is mixed with the gastric juice until every bit of it that will be of any use to the body has become fluid in character. Not only does the gastric juice make the food liquid, but it acts on it and changes some of it so that it will be suitable for use by the little cells of the body. As fast as the food is made liquid by the juices of the stomach it is allowed to pass into the intestine through an opening called thepyloric opening.The intestineThe intestine is a long, narrow, twisting and turning tube that is divided into two principal parts, the large and small intestine. In the walls of the intestine are many little glands that secrete a fluid that helps in digesting the food. Two fluids, one made by the liver, the other by the pancreas, are brought into the intestine by two small tubes, which come together in the wall of the intestine six or seven inches below the pyloric opening. These fluids perform a very important part in the digestion of all the different foodstuffs.Villi and lymphaticsBesides the little glands in the walls of the intestine there are many thousands of little finger-like projections standing up from the walls. These are calledvilli. Each villus has in it very small vessels, into which the food passes after it has been digested. These vessels are of two sorts: blood vessels, which take up the digested starch and proteid foods, and another sort known aslymphatics, which take up the fats. All the lymphatics combine into a single vessel which empties into the great vein at the base of the neck. Thus the fatty foods pass into the blood and are mingled with the food materials taken up directly by the blood vessels.CIRCULATION OF THE BLOODTwo kinds of blood vesselsThere are two kinds of blood vessels in the body. We call themarteriesandveins. The arteries serve to carry the blood from the heart to all parts of the body, and the veins serve to carry the blood back to the heart. The heart is really a part of the blood vessels, half of each side being like the veins and half like the arteries.Arteries and veinsThe walls of the arteries are thicker than those of the veins. Two sets of arteries leave the heart, one from each side. The artery that starts from the right side of the heart goes to the lungs and carriesvenous blood, which has a very poor supply of oxygen and is full of impurities. We call thisthepulmonary artery. The artery that leaves the left side of the heart goes to all parts of the body but the lungs and carriesarterial blood, which has much more oxygen and is much more free from impurities.CapillariesIf we follow the blood as it circulates we will see how it reaches all parts of the body. The big artery that leaves the left side of the heart divides into smaller and smaller arteries until there are branches going to every part of the body. These branches keep dividing until they are so small that we call themarterioles, and these little arterioles again divide and become so small that we call themcapillaries.Changes in the bloodWhile the blood is passing through the arterioles and the capillaries, something is happening to it. The little cells with which these small vessels come in contact have been taking the oxygen and the nourishing material out of the blood. At the same time they have been putting something into the blood. In place of the oxygen they have been putting in carbon dioxid and in place of the nourishing material they have been putting in the worn-out materials from the cells. As the blood passes through certain parts of the body, such as the kidneys, the worn-out materials from the cells are taken out of the blood and sent out of the body. The carbon dioxid is left in the blood until it goes to the lungs.Fig. 83.The white vessels represent the circulation of the arterial blood; the gray, the circulation of the venous blood.Venous bloodThe blood has now been followed to the capillaries, where oxygen and nourishing material have been taken out of it, and where something else has been added to it. As we follow a little capillary, we find that instead of dividing again, it joins others and gradually grows larger. As these blood vessels grow larger the walls do not become so thick as the walls of the arteries of the same size. These larger vessels formed by the union of capillaries are calledveins. In other words, the veins are simply continuations of the arteries that have divided into extremely small branches and have now come together again. The blood which has been changed is now calledvenous blood. It has much less oxygen in it, but has received a great deal of carbon dioxid. The veinscontinue to come together, until finally they form a single large vein which empties into the upper half of the right side of the heart. From there the blood is driven into the lower half of the right side of the heart and thence to the pulmonary artery, which goes to the lungs. The blood is not changed in the heart, so what goes into the pulmonary artery is still venous blood.Arterial bloodThe blood goes straight from the heart to the lungs and there it is changed into arterial blood. The change consists in taking oxygen from the air and giving off carbon dioxid to the air. From the lungs the blood goes through the capillaries again into the veins, the small capillaries in the lungs uniting to form the pulmonary veins. These veins finally unite into one vein that empties into the upper half of the left side of the heart, and from there the blood goes to the lower half of the same side. The blood has now reached its starting point and is ready to begin its journey again. The journey of the blood is as follows:Entire circulationFrom the right side of the heart to the arteries; from arteries into arterioles; from arterioles to capillaries; from capillaries into veins; from veins into the heart; from the heart to the lungs; and from the lungs back to the heart again.THE RESPIRATORY SYSTEMUse of the respiratory systemThat portion of the body by which we breathe is called the respiratory system. This system is composed of thenasal passage, thepharynx, thelarynx, thetrachea, thebronchi, and thelungs. The mouth is not a part of the respiratory system; we should never breathe through our mouths.The use of the nose in breathingAs the air passes through the nasal passage it is warmed and moistened, and a great deal of dust and dirt is taken out of it. Thus the nasal passage serves to warm, to moisten, and to clean the air we breathe, and is a very important part of the respiratory system, since either cold or dry air is very irritating to the lungs.Fig. 84.The air passages of the head and throat.Pharynx, larynx, and tracheaThere is only one tube leading from the back of the nasal passage to the lungs. Different parts of this tube are given different names. The pharynx is that part that extends from the back of the nose to the vocal chords. The larynx is the part of the throat where the vocal chords are located. We sometimes call it the "Adam's apple." It is very prominent in some men, but seldom noticeable in women. The trachea is the part of the tube leading down from the larynx. At the lower end of the trachea the tube divides into two parts that we call the bronchi, one leading to each lung.The bronchiThe bronchi carry the air from the trachea to the lungs. They divide again and again until they become so small that there is a branch for each little air cell in the lungs.Fig. 85.The lungs.The lungsThe lungs are the most important part of the respiratory system. They are made up of lobes. There are two lobes in the left lung and three in the right. Each lobe is divided intolobules, which means small lobes. Each lobule is divided into air spaces. In these air spaces, or cells, the work of the lungs is performed.Air cellsThe capillaries run in the thin walls of the air spaces. The walls of these fine blood vessels are so very thin that the air in the air cells comes in almost direct contact with theblood in the vessels. While the blood is passing through the vessels in the walls of the air spaces, something happens to both the blood and the air. The air we take into our lungs contains a great deal of oxygen and very little carbon dioxid. The air that comes out of our lungs contains a great deal of carbon dioxid and much less oxygen. In other words, the oxygen from the air goes into the blood, and the carbon dioxid from the blood goes out into the air.Necessity of pure airIf the air we breathe is not pure and does not containenough oxygen, the blood cannot get all the oxygen we need, and the cells of the body become sick and die. If, when we breathe, we do not fill each little air cell in our lungs with air, a great deal of the blood sent to the lungs for oxygen cannot get it. If we wear very tight clothing we cannot take a full breath and hence cannot fill all the air spaces with air. If the air spaces in the lungs are not filled, the blood does not get the oxygen it needs, as there is no other place in the body to get it.THE EYE AND THE EARThe eye compared to a cameraThe eye is one of the most important organs in the body and also one of the most delicate. It is very much like a camera.The cornea and the scleraWhen you look at an eye you are likely to think that the front of it is blue or brown. The colored part is not the front of the eye. If you look at the eye from the side you will see that there is a curved part in front of the colored part and that the curved part is perfectly clear. This curved clear part of the eye we call thecornea. The cornea connects with the white part of the eye, and this white part extends all around the rest of the eye, except at a small point in the back where theoptic nervecomes through. This white part we call thesclera.Aqueous humorThe space between the cornea and the colored part of the eye is filled with a clear fluid that is called theaqueous humor, which means watery fluid. The space occupied by this fluid is called theanterior chamberof the eye.The irisThe iris, which is the colored portion of the eye, is a curtain that is hung between the anterior and posterior chambers of the eye. It prevents any light getting into the posterior chamber except that which passes through a round hole in the iris called thepupil. The pupil grows larger or smaller according to the amount of light needed by the eye. If you look away from a bright light at something in the dark, thepupil grows larger; if you look back at the light, it grows smaller. You can see this in a hand mirror.LensBehind the pupil is a clear mass shaped like a very strong magnifying glass. This is thelens. The lens causes to be formed on the back of the eye a clear picture of whatever you are looking at. When you focus a camera, you move the back towards or away from the lens. When you focus your eye you cannot move the back of the eye, but you can make the lens more or less convex as may be needed to make a clear picture.Fig. 86.A cross-section of the eye.Vitreous humorBehind the iris and the lens, we find the posterior chamber of the eye. This occupies by far the greater portion of the ball and corresponds to the dark chamber of a camera. This chamber is filled with a clear fluid called thevitreous humor, which means jelly-like fluid. It is a clear, gelatinous substance.The retina and the optic nerveThe optic nerve enters the eyeball from the back and spreads its fibers out in a thin membrane called theretina, which corresponds to the sensitive plate in a camera. The lens focuses on the retina the image of any object you look at. The impression made on the minute nerve endings in the retina is carried by the optic nerve fibers to the brain. When this impression reaches the brain we see the object.Movements of the eyeEach eye has six muscles that turn it in whatever direction you want to look. These muscles are very delicate, and for true sight they must be exactly adjusted. If the muscles on one side of the eye are stronger than those on the other side, you will be cross-eyed or wall-eyed. If one of the muscles in one eye is stronger than the corresponding muscle in the other eye, it pulls the eyeball out of place and you "see double."The use of the outer earThe portion of the ear that you see on the side of your head has as much to do with hearing as the outer rim of the horn into which you speak has to do with making a record for the phonograph. You know that the record is really made at the little end of the horn, while the big end simply collects the sound. The outside portion of the ear simply collects sounds, and the real hearing is done with the portion of the ear that is not seen.Fig. 87.The ear, showing the outer, middle, and the inner part.The outer ear connects with the short tube that leads to thedrum, which is a thin membrane that separates the middle ear from the outer ear. This drum does not have so much to do with hearing as is supposed. To have a hole in the drum does not mean that you cannot hear.The middle earThe middle ear is that portion which is just inside the drum. In this we find a chain of little bones. The one attached to the drum is shaped much like a hammer, andis called themalleus, which means mallet or hammer. The next one is shaped like an anvil and is calledincus, which means anvil, and the third is calledstapes, which means stirrup. The flat part of the stapes fits into a small opening that leads to the internal ear.The inner earThe internal ear is shaped like a snail shell. It makes several turns, which are hollow like the ends of a conch shell. In these channels the nerve that receives the impressions made by the sounds is distributed. This nerve carries the impressions to the brain.Fig. 88.The nervous system.THE NERVOUS SYSTEMImportance of the nervous systemThis system is so important in its use and so difficult to understand in its details, that a description of it should have more space than can be given in this summary. Can you imagine having no feeling and being unable to move? This would be your condition if you had no nerves.Nerves compared to telegraph systemBriefly, the nerves might be called the telegraph system of the body. There is a great central station called the brain where messages are received and sent out; there are many sub-stations that make up the spinal cord. Twelve great nerves pass directly from the brain to the body; all others pass from the spinal cord.Extent of nervous systemEvery nerve leaving these centres divides and sub-divides into little threads as the arteries divide and sub-divide into arterioles and capillaries, until every part of the body—every muscle and part of the skin—has its nerve.Voluntary and reflex actionEvery time youchooseto move your hand, your brain sends to the necessary muscles an instantaneous order to act. This is calledvoluntary action. If you put your finger against a hot stove you jerk it away before you could have time tochooseto do it. This happens as an order from a sub-station and is calledreflex action.Messages travel both ways and it is necessary that the nervous connection with every part of the body remain unbroken, and important that the nervous condition be kept healthy.
The framework of the body
The framework of the body is composed of bones. There are 206 bones (not including the teeth) in the body. The bones of the body are divided into four classes—long bones, short bones, flat bones, and irregular bones.
Construction of bones
Regardless of their shape, all bones are composed in the same way. Every bone has an outer and an inner portion. The outer portion is a dense layer calledcompact bone. The inner portion is more open, and is much weaker; this is calledcancellated bone(fromcancella, a sponge). In the smaller bones, the marrow, which is quite soft, runs through the spongy bone; in the larger long bones, the marrow is distinct and is enclosed by the spongy bone.
The periosteum
Every bone is covered by a thick, tough layer, theperiosteum, which has three uses. When the bone is injured by disease or accident, the periosteum makes new bone to fill in and repair the break. It also builds new bone on the surface of the old as long as the body is growing. Finally, the periosteum gives strong and firm attachment to the muscles, which send tendons into it.
Joints
Every bone in the body (except the hyoid bone, to which the tongue is attached) is joined with some other bone. Most of them join with two or more bones. In most instances the end of a bone which joins with another is rounded off and made very smooth, so that it can slide easily over the other bone. There are three principal kinds of joints in the body. They are called theball and socketjoint, thehingejoint, and theserratedorsaw-toothjoint.
Fig. 77.The skeleton.
Fig. 77.The skeleton.
The ball and socket joint
The ball and socket joint is one that can move freely in all directions. We see it illustrated in the joints of the shoulderand hip. In these joints one of the bones has a deep depression in it, and this depression forms thesocket. The other bone has a rounded head that fits into the depression. We call this rounded head theball.
Fig. 78.The structure of a bone.
Fig. 78.The structure of a bone.
The hinge joint
The hinge joint is illustrated in the knee and elbow joints. These joints can move backward and forward in one plane like a hinge, but they cannot move in a circle like the ball and socket joints. You cannot swing your forearm about on a pivot at the elbow as you can your whole arm, nor will the knee joint bend in every direction as does the joint at the hip.
Serrated joints
Serrated joints do not move. The bones having serrated joints are fitted tightly together so that they form practically one bone. We find this kind of joint illustrated in the way the bones of the skull are put together.
Ligaments
The joints of the body are not held together by rivets, pins or bolts as are the joints of a machine, but by bands of very tough tissue placed about a joint in such a way as to allow it to move freely, although the bones are all the time held firmly together. These bands are calledligaments. Ligaments are much better than bolts or pegs would be, because they stretch a little, and thus prevent the breaking of the bones when the joint is put under a severe strain.
Fig. 79.The muscles.
Fig. 79.The muscles.
What muscle is
The lean meat of any animal is composed entirely of muscle tissue. It is the function of the muscles to move the body.
Fig. 80.The biceps muscle contracted.
Fig. 80.The biceps muscle contracted.
How the muscles work
The muscles are nearly all attached to the bones. They are just long enough to let the joint straighten out when the muscles are at rest, but when the joint bends the muscle contracts. When a muscle contracts it becomes shorter and thicker. Sometimes it becomes very much thicker in one place. Every boy knows how much thicker the arm muscle (biceps) becomes when he bends his elbow hard. He calls this "showing his muscle."
Tendons
There is not room enough on most of the bones for all the muscles to be attached directly to them. Instead of being thus attached directly to the bone, they end in what we calltendons. These tendons are hard and strong, and a very small tendon will lift as much without breaking as quite a large muscle. The muscles are soft and would have to be attached over a large area in order to secure the required strength. The tendons, being so much stronger than the muscles, can be attached to a very small area and yet secure the same amount of power as would result from attaching the muscle itself.
The tendons pass directly into the periosteum, the thick, strong covering of the bones. So strong is this attachment that the bone will often break before the tendon will pull loose.
The skin as an armor
The entire body is covered with skin, which regulates the heat of the body and acts as an armor against blows and cuts which would otherwise injure the delicate nerves and blood vessels beneath. It also serves to some extent to keep out the germs of disease. The skin appears to be smooth, but if you examine it through a strong magnifying glass you will see that it is divided into little areas. The dividing lines do not run straight, however, and the areas are not square like those you find on a checkerboard.
Fig. 81.A section of the skin, highly magnified.
Fig. 81.A section of the skin, highly magnified.
Sweat glands
After looking at the skin with a strong magnifying glass you will think that you must have seen all its irregularities, but if you will look at it with a powerful microscope you will find out many other things. In the first place you will see many little openings in the skin. These little openings make the ridges which divide the skin into little areas. Some of the openings aresweat glands, and there is always some perspiration coming out of them. When you are very warm you can see, without the aid of the glass, the drops of perspiration as they come out on the surface of the skin. When you are not very warm you cannot see these drops of perspiration, but they are nevertheless coming out all the time. When the perspiration comes so slowly that you cannot see it, it is calledinsensible perspiration.
Hair
The whole body is covered with hair. You can see the hair on your head and some of the hair on your arms and the backs of your hands, but most of the hair on the body is so fine that you cannot see it without a microscope. Each of the fine hairs on the body has a root that goes through the skin just as the root from each hair on your head goes through it.
Sebaceous glands
Opening into the little pockets in which the hairs stand, are glands that secrete a kind of oily material. They are calledsebaceous glandsorfollicles. Sometimes these follicles become stopped up; then the material they secrete becomes thick and cheesy, and the little black points appear on the skin which we callblackheads. The white matter which comes out of these blackheads is merely the secretion of the glands from which the water has been absorbed, leaving the solid or cheesy portion.
Nails
There is a part of the skin that we do not usually think of as skin. We mean thenails. The finger nails and the toe nails do not look like the rest of the skin of the body, but they are made of just the same kind of cells. The cells of the nails are flat, dead, and closely packed together. There are no sweat glands, or sebaceous glands, or any hairs in the nails.
The alimentary canal
The digestive system is the part of our bodies in which the food we eat is so changed that it can be made use of by the little cells in the body. It is composed of a long canal with many parts and enlargements, each part necessary for a certain required work. This canal as a whole is called thealimentary canal.
Teeth
The mouth does the first part of the work for the digestive system. Here we find the teeth, which are used for grinding the food. The teeth are composed of three parts, thehead(orcrown), theneckand theroot. The head, orcrown, is very hard. Each tooth is hollow, and in the hollow portion there are nerves and blood vessels.
The salivary glands
Opening into the mouth are three pairs of glands known assalivary glands. One pair of glands is located just above the angle of the jaw. It is these glands that become swollen when we have mumps. Another pair of glands is placed just inside the jaw bone, near the root of the tongue, and the third pair is located under the tongue. These three pairs of glands secrete the saliva which moistens the food and aids in digesting the starch.
Fig. 82.The alimentary canal.
Fig. 82.The alimentary canal.
The esophagus
The food passes from the mouth; through a passage called theesophagus, or gullet, to thestomach.
The stomach
The stomach is one of the enlarged parts of the alimentary canal. Its walls are quite thick, and in these walls are thousands of little glands. These glands secrete a fluid calledgastric juice. When the food enters the stomach it is held there for a long time, and the walls of the stomach squeeze upon it so that the food is mixed with the gastric juice until every bit of it that will be of any use to the body has become fluid in character. Not only does the gastric juice make the food liquid, but it acts on it and changes some of it so that it will be suitable for use by the little cells of the body. As fast as the food is made liquid by the juices of the stomach it is allowed to pass into the intestine through an opening called thepyloric opening.
The intestine
The intestine is a long, narrow, twisting and turning tube that is divided into two principal parts, the large and small intestine. In the walls of the intestine are many little glands that secrete a fluid that helps in digesting the food. Two fluids, one made by the liver, the other by the pancreas, are brought into the intestine by two small tubes, which come together in the wall of the intestine six or seven inches below the pyloric opening. These fluids perform a very important part in the digestion of all the different foodstuffs.
Villi and lymphatics
Besides the little glands in the walls of the intestine there are many thousands of little finger-like projections standing up from the walls. These are calledvilli. Each villus has in it very small vessels, into which the food passes after it has been digested. These vessels are of two sorts: blood vessels, which take up the digested starch and proteid foods, and another sort known aslymphatics, which take up the fats. All the lymphatics combine into a single vessel which empties into the great vein at the base of the neck. Thus the fatty foods pass into the blood and are mingled with the food materials taken up directly by the blood vessels.
Two kinds of blood vessels
There are two kinds of blood vessels in the body. We call themarteriesandveins. The arteries serve to carry the blood from the heart to all parts of the body, and the veins serve to carry the blood back to the heart. The heart is really a part of the blood vessels, half of each side being like the veins and half like the arteries.
Arteries and veins
The walls of the arteries are thicker than those of the veins. Two sets of arteries leave the heart, one from each side. The artery that starts from the right side of the heart goes to the lungs and carriesvenous blood, which has a very poor supply of oxygen and is full of impurities. We call thisthepulmonary artery. The artery that leaves the left side of the heart goes to all parts of the body but the lungs and carriesarterial blood, which has much more oxygen and is much more free from impurities.
Capillaries
If we follow the blood as it circulates we will see how it reaches all parts of the body. The big artery that leaves the left side of the heart divides into smaller and smaller arteries until there are branches going to every part of the body. These branches keep dividing until they are so small that we call themarterioles, and these little arterioles again divide and become so small that we call themcapillaries.
Changes in the blood
While the blood is passing through the arterioles and the capillaries, something is happening to it. The little cells with which these small vessels come in contact have been taking the oxygen and the nourishing material out of the blood. At the same time they have been putting something into the blood. In place of the oxygen they have been putting in carbon dioxid and in place of the nourishing material they have been putting in the worn-out materials from the cells. As the blood passes through certain parts of the body, such as the kidneys, the worn-out materials from the cells are taken out of the blood and sent out of the body. The carbon dioxid is left in the blood until it goes to the lungs.
Fig. 83.The white vessels represent the circulation of the arterial blood; the gray, the circulation of the venous blood.
Fig. 83.The white vessels represent the circulation of the arterial blood; the gray, the circulation of the venous blood.
Venous blood
The blood has now been followed to the capillaries, where oxygen and nourishing material have been taken out of it, and where something else has been added to it. As we follow a little capillary, we find that instead of dividing again, it joins others and gradually grows larger. As these blood vessels grow larger the walls do not become so thick as the walls of the arteries of the same size. These larger vessels formed by the union of capillaries are calledveins. In other words, the veins are simply continuations of the arteries that have divided into extremely small branches and have now come together again. The blood which has been changed is now calledvenous blood. It has much less oxygen in it, but has received a great deal of carbon dioxid. The veinscontinue to come together, until finally they form a single large vein which empties into the upper half of the right side of the heart. From there the blood is driven into the lower half of the right side of the heart and thence to the pulmonary artery, which goes to the lungs. The blood is not changed in the heart, so what goes into the pulmonary artery is still venous blood.
Arterial blood
The blood goes straight from the heart to the lungs and there it is changed into arterial blood. The change consists in taking oxygen from the air and giving off carbon dioxid to the air. From the lungs the blood goes through the capillaries again into the veins, the small capillaries in the lungs uniting to form the pulmonary veins. These veins finally unite into one vein that empties into the upper half of the left side of the heart, and from there the blood goes to the lower half of the same side. The blood has now reached its starting point and is ready to begin its journey again. The journey of the blood is as follows:
Entire circulation
From the right side of the heart to the arteries; from arteries into arterioles; from arterioles to capillaries; from capillaries into veins; from veins into the heart; from the heart to the lungs; and from the lungs back to the heart again.
Use of the respiratory system
That portion of the body by which we breathe is called the respiratory system. This system is composed of thenasal passage, thepharynx, thelarynx, thetrachea, thebronchi, and thelungs. The mouth is not a part of the respiratory system; we should never breathe through our mouths.
The use of the nose in breathing
As the air passes through the nasal passage it is warmed and moistened, and a great deal of dust and dirt is taken out of it. Thus the nasal passage serves to warm, to moisten, and to clean the air we breathe, and is a very important part of the respiratory system, since either cold or dry air is very irritating to the lungs.
Fig. 84.The air passages of the head and throat.
Fig. 84.The air passages of the head and throat.
Pharynx, larynx, and trachea
There is only one tube leading from the back of the nasal passage to the lungs. Different parts of this tube are given different names. The pharynx is that part that extends from the back of the nose to the vocal chords. The larynx is the part of the throat where the vocal chords are located. We sometimes call it the "Adam's apple." It is very prominent in some men, but seldom noticeable in women. The trachea is the part of the tube leading down from the larynx. At the lower end of the trachea the tube divides into two parts that we call the bronchi, one leading to each lung.
The bronchi
The bronchi carry the air from the trachea to the lungs. They divide again and again until they become so small that there is a branch for each little air cell in the lungs.
Fig. 85.The lungs.
Fig. 85.The lungs.
The lungs
The lungs are the most important part of the respiratory system. They are made up of lobes. There are two lobes in the left lung and three in the right. Each lobe is divided intolobules, which means small lobes. Each lobule is divided into air spaces. In these air spaces, or cells, the work of the lungs is performed.
Air cells
The capillaries run in the thin walls of the air spaces. The walls of these fine blood vessels are so very thin that the air in the air cells comes in almost direct contact with theblood in the vessels. While the blood is passing through the vessels in the walls of the air spaces, something happens to both the blood and the air. The air we take into our lungs contains a great deal of oxygen and very little carbon dioxid. The air that comes out of our lungs contains a great deal of carbon dioxid and much less oxygen. In other words, the oxygen from the air goes into the blood, and the carbon dioxid from the blood goes out into the air.
Necessity of pure air
If the air we breathe is not pure and does not containenough oxygen, the blood cannot get all the oxygen we need, and the cells of the body become sick and die. If, when we breathe, we do not fill each little air cell in our lungs with air, a great deal of the blood sent to the lungs for oxygen cannot get it. If we wear very tight clothing we cannot take a full breath and hence cannot fill all the air spaces with air. If the air spaces in the lungs are not filled, the blood does not get the oxygen it needs, as there is no other place in the body to get it.
The eye compared to a camera
The eye is one of the most important organs in the body and also one of the most delicate. It is very much like a camera.
The cornea and the sclera
When you look at an eye you are likely to think that the front of it is blue or brown. The colored part is not the front of the eye. If you look at the eye from the side you will see that there is a curved part in front of the colored part and that the curved part is perfectly clear. This curved clear part of the eye we call thecornea. The cornea connects with the white part of the eye, and this white part extends all around the rest of the eye, except at a small point in the back where theoptic nervecomes through. This white part we call thesclera.
Aqueous humor
The space between the cornea and the colored part of the eye is filled with a clear fluid that is called theaqueous humor, which means watery fluid. The space occupied by this fluid is called theanterior chamberof the eye.
The iris
The iris, which is the colored portion of the eye, is a curtain that is hung between the anterior and posterior chambers of the eye. It prevents any light getting into the posterior chamber except that which passes through a round hole in the iris called thepupil. The pupil grows larger or smaller according to the amount of light needed by the eye. If you look away from a bright light at something in the dark, thepupil grows larger; if you look back at the light, it grows smaller. You can see this in a hand mirror.
Lens
Behind the pupil is a clear mass shaped like a very strong magnifying glass. This is thelens. The lens causes to be formed on the back of the eye a clear picture of whatever you are looking at. When you focus a camera, you move the back towards or away from the lens. When you focus your eye you cannot move the back of the eye, but you can make the lens more or less convex as may be needed to make a clear picture.
Fig. 86.A cross-section of the eye.
Fig. 86.A cross-section of the eye.
Vitreous humor
Behind the iris and the lens, we find the posterior chamber of the eye. This occupies by far the greater portion of the ball and corresponds to the dark chamber of a camera. This chamber is filled with a clear fluid called thevitreous humor, which means jelly-like fluid. It is a clear, gelatinous substance.
The retina and the optic nerve
The optic nerve enters the eyeball from the back and spreads its fibers out in a thin membrane called theretina, which corresponds to the sensitive plate in a camera. The lens focuses on the retina the image of any object you look at. The impression made on the minute nerve endings in the retina is carried by the optic nerve fibers to the brain. When this impression reaches the brain we see the object.
Movements of the eye
Each eye has six muscles that turn it in whatever direction you want to look. These muscles are very delicate, and for true sight they must be exactly adjusted. If the muscles on one side of the eye are stronger than those on the other side, you will be cross-eyed or wall-eyed. If one of the muscles in one eye is stronger than the corresponding muscle in the other eye, it pulls the eyeball out of place and you "see double."
The use of the outer ear
The portion of the ear that you see on the side of your head has as much to do with hearing as the outer rim of the horn into which you speak has to do with making a record for the phonograph. You know that the record is really made at the little end of the horn, while the big end simply collects the sound. The outside portion of the ear simply collects sounds, and the real hearing is done with the portion of the ear that is not seen.
Fig. 87.The ear, showing the outer, middle, and the inner part.
Fig. 87.The ear, showing the outer, middle, and the inner part.
The outer ear connects with the short tube that leads to thedrum, which is a thin membrane that separates the middle ear from the outer ear. This drum does not have so much to do with hearing as is supposed. To have a hole in the drum does not mean that you cannot hear.
The middle ear
The middle ear is that portion which is just inside the drum. In this we find a chain of little bones. The one attached to the drum is shaped much like a hammer, andis called themalleus, which means mallet or hammer. The next one is shaped like an anvil and is calledincus, which means anvil, and the third is calledstapes, which means stirrup. The flat part of the stapes fits into a small opening that leads to the internal ear.
The inner ear
The internal ear is shaped like a snail shell. It makes several turns, which are hollow like the ends of a conch shell. In these channels the nerve that receives the impressions made by the sounds is distributed. This nerve carries the impressions to the brain.
Fig. 88.The nervous system.
Fig. 88.The nervous system.
Importance of the nervous system
This system is so important in its use and so difficult to understand in its details, that a description of it should have more space than can be given in this summary. Can you imagine having no feeling and being unable to move? This would be your condition if you had no nerves.
Nerves compared to telegraph system
Briefly, the nerves might be called the telegraph system of the body. There is a great central station called the brain where messages are received and sent out; there are many sub-stations that make up the spinal cord. Twelve great nerves pass directly from the brain to the body; all others pass from the spinal cord.
Extent of nervous system
Every nerve leaving these centres divides and sub-divides into little threads as the arteries divide and sub-divide into arterioles and capillaries, until every part of the body—every muscle and part of the skin—has its nerve.
Voluntary and reflex action
Every time youchooseto move your hand, your brain sends to the necessary muscles an instantaneous order to act. This is calledvoluntary action. If you put your finger against a hot stove you jerk it away before you could have time tochooseto do it. This happens as an order from a sub-station and is calledreflex action.
Messages travel both ways and it is necessary that the nervous connection with every part of the body remain unbroken, and important that the nervous condition be kept healthy.
A false delicacy has often prevented the teaching of vital lessons to growing children. The day is how at hand when foolish sentiment must no longer prevent the spread of any knowledge which is necessary to exterminate the plagues that have afflicted the race.In chapters 17, 18, 19 and 32, unpleasant facts are given in plain language. They are facts that parents do not teach their children and that most teachers will not frankly treat with classes in a school. Though they are disagreeable to discuss, they are essential for children of school age to know. Now that the dependence of public health upon personal hygiene is recognized, personal habits and sanitary conditions are more frankly dealt with than formerly.It is an excellent thing occasionally, to have one or two points of an assigned lesson answered in writing. Any topic that the teacher may think advisable to treat in this manner may be discussed on paper at the beginning of the recitation, five or six minutes being allowed for that purpose. Even a whole chapter may be assigned to be studied with a view of answering in writing the questions at the end of the chapter. The written test can then take the place of the usual oral recitation. This method is suggested to the teacher who hesitates to discuss orally certain plain but essential facts.Chapter 32 on the Spread and Prevention of Consumption can be treated with best results orally, if the pupils are first made tofeelthe great danger of consumption and to realize the possibility of preventing the vast havoc wrought by that dread disease. The attitude of teacher and pupils should be that while the discussion may be disagreeable, the disgusting habits referred to in the text are so commonly practised that unless their dangers are taught this disease can never be wiped out.
A false delicacy has often prevented the teaching of vital lessons to growing children. The day is how at hand when foolish sentiment must no longer prevent the spread of any knowledge which is necessary to exterminate the plagues that have afflicted the race.
In chapters 17, 18, 19 and 32, unpleasant facts are given in plain language. They are facts that parents do not teach their children and that most teachers will not frankly treat with classes in a school. Though they are disagreeable to discuss, they are essential for children of school age to know. Now that the dependence of public health upon personal hygiene is recognized, personal habits and sanitary conditions are more frankly dealt with than formerly.
It is an excellent thing occasionally, to have one or two points of an assigned lesson answered in writing. Any topic that the teacher may think advisable to treat in this manner may be discussed on paper at the beginning of the recitation, five or six minutes being allowed for that purpose. Even a whole chapter may be assigned to be studied with a view of answering in writing the questions at the end of the chapter. The written test can then take the place of the usual oral recitation. This method is suggested to the teacher who hesitates to discuss orally certain plain but essential facts.
Chapter 32 on the Spread and Prevention of Consumption can be treated with best results orally, if the pupils are first made tofeelthe great danger of consumption and to realize the possibility of preventing the vast havoc wrought by that dread disease. The attitude of teacher and pupils should be that while the discussion may be disagreeable, the disgusting habits referred to in the text are so commonly practised that unless their dangers are taught this disease can never be wiped out.
Adenoids,49,50Air, amount necessary for health,45;effects of impure,45–48;fresh air, when needed,45–48;how secured,46,47;how changed in body,45;necessity of pure air,45–48Air cells,175Alcohol, effect of, on body,67–70;on brain work,70;on consumptives,69;on descendants,69;on liver,68;on morals,69;on nervous system,69;on powers of resistance,68;on stomach,67;false ideas about effects of,67;what business men think of,70Alimentary canal,169,170Amoebic dysentery, how prevented,122;how spread,122;where prevalent,122Animals free from typhoid fever,113Antitoxin, how it acts,108–110;how discovered,109;sometimes considered a poison,111;prevents diphtheria,110;saves lives,110Aqueous humor,177Arterial blood,172Arteries,171Articles used by the sick, dangers from,75;how to treat,76Bathing, importance of,60;frequency of,60Baths, hot,61;cold,61Bedtime for children,51Blood, arterial,172;how changed in the body,174;venous,171,172Boils, how caused,95,99Bones,163Bronchi,175Building foods,14,15Candy, when harmful,54;when not harmful,54Canned meats, why poisonous,32Capillaries,172Cells, are alive,6;body made of,6;body needs new,14;how killed,7;must not be killed,6;size of a,5;what they are like,5Circulation of the blood,171–174Clothing, effect of damp,11;promotes health,9;proper weight of,10Common drinking cup,153Consumption.SeeTuberculosisCooking, effects of improper,34,35;fatty foods,34;meats,35;starchy foods,34Cornea,177Coughing, dangers from,147,150–153;how to prevent dangers from,152,153Cuspidors, in public buildings,152;pocket,152;street,152Dairy, sickness about a,26,103,115Decomposed foods dangerous,30,32Decomposition, cause of,30;effect of cold on,31;of foods,30–32Desserts, when harmful,40;when not harmful,40Dining table, effect of dirty,37;cheerfulness at,37Diphtheria, cure of,108–111;germs present after recovery,101,102;germs present when throat is not sore,104;how to confine germs,100;how poison is fought,108–110;mild cases, how detected,104;nature of the poison,108;prevalence of,100;where germs come from,100;why some cases are not quarantined,102–104Dirt, a cause of sickness,77,78;getting into milk from cows,23,117;from cow barns,23–25;from milk cans and bottles,26,27;from milkmen,25;from flies,28,80,81Diseased animals, effect on meats,19–21;effect on milk,28;tuberculosis from,28,155Drafts, evil effects of,10;how to prevent harm from,10Ear, care of,58;drum,179;inner ear,181;middle ear,179;outer ear,179Esophagus,170Excreta from sick, how dispose of,76,118Exercise, necessity of,51,161Eye, how germs get into,56;how overworked,57;method of testing,58Far sight,58Flies, breeding places for,77,80;as germ carriers,80,81,116;how to get rid of,82,83;how to keep out,83Fly screens, where needed,83Foods, advertised,16;building,14–16;decomposition of,30–32;heat-producing,14–16;improper cooking of,34,35;cost of suitable,16;uses of foods,14–17;uses of starches,14;uses of fats,15;value of meat as a,15;value of milk as a,14Garbage cans, should be covered,83Germs, cause of poison in meats,31,32;carried by dogs and cats,106;effect of, in wounds,95–99;how, get through the skin,95;how, get into the body,79;how, get into foods,79,80;how put into the air,147,150;how kept out of the air,151,152;how to fight,74;of lockjaw,98;man's greatest foe,1;nature of a,73;not alike,73;not killed by running water,115Hair,169Hearing, how tested,58Heat, how kept up in the body,14Hookworm disease, character of the worm,120;how it enters the body,121;how prevented,122;nature of the disease,121;where worm lives in the body,121;where prevalent,122Insects that carry disease,92–94Intestines,171Iris,177Joints,163Larynx,174,175Lens, the,178Ligaments,165Lungs,175Lymphatics,171Malaria, how transmitted,92;how prevented,93Manure, a hatching place for flies,80,82;how to dispose of,82Meal times, frequency of,53;regularity of,53;should be pleasant,37,38Measles, after effects of,128;fatality of,128;necessity of care in,129;seriousness of,128;why to avoid,128Meats, characteristics of good,18;Clean Meat League,19;from diseased animals,19–21;germs cause poison in,19,32;how kept clean,18;should be cooked,35;value of, as a food,18Milk, as carrier of disease,22,117;effect of germs on,22;effect of disease in cow on,28;flies in,28;how germs get into,23–28;impure, dangerous,22;polluted water in,27;typhoid fever carried by,117;value of, as a food,14,20Mosquitoes, as disease carriers,92,93;how to get rid of,94Mouth, why some breathe through,49Mouth-breathing, effect of,50Muscles, attachment of,167Nails, how to care for,61,62Near sight,57Nerves, compared to telegraph system,181;distribution of,181Nose, importance of breathing through,48Overcoats, necessity of,12Overwork, effect of,51,52Paper napkins for consumptives,152Parties, time for,53Pencils in mouth,155Pharynx,175Play a form of work,52Playgrounds,161Pocket cuspidors,152Ptomaines,19Quarantine, breaking, shows selfishness,126;how broken by family,105;rules of,105;seriousness of breaking,101;when safe to raise,102;why necessary,101;why some cases escape,102–104Reflex action,181Respiratory system,174–177Rest, proper amount of,51Retina,178Rocky Mountain Spotted (Tick) Fever, how transmitted,94Rubbers, necessity of wearing,11Saliva, effect of, on starches,39,41Salivary glands,170Scarlet fever, a dangerous disease,124;mild cases dangerous,123,124Scarlatina,125Scarlet rash, why quarantine is necessary in,125School lunches,37Sclera,177Sebaceous glands,169Sewage, effect of, on water,85–87,115Sickness about a dairy,26,103,115;due to germs, how prevented,3Sick room, stay away from,75Skin, care of,60,61Smallpox, fatality of,131;how prevented,135–137;during Franco-Prussian War,132;in Sweden,133;in Gloucester,134;in the Philippine Islands,134Spitting, dangers from,151;how avoided,152;where to spit,152,153;where not to spit,151Springs, how polluted,87Street cuspidors,152Sunshine, effect of, on germs,77,78Suppuration, how the surgeon prevents,96;how you may prevent,97;real cause of,96Sweat glands, the work of,60Teeth, brittle,42;dangers from poor,41–43;how to care for,43;necessity of baby teeth,41;uses of teeth,41;why, decay,42Tendons,167Tobacco, a poison,64;effect of, on blood,65;on heart,66;on nervous system,66;on nose and throat,65;on stomach,66;extra work caused by,64Toilets, improper construction of,86;proper construction of,87;relation to wells,85–87Tonsils,49,50Trachea,175Tuberculin test,155,156Tuberculosis, can be prevented,142,148,157;fatality of,142;fresh air in,157,158;germ, discovery of the,145;how to get, out of a house,147,148;how germs leave the body,150,151;how spread from cows,28,155;how spread from the lips,153–155;how detected in cows,155;a house disease,146,147;not inherited,146;of the glands,144;of the joints,143;of the spine,144;of the stomach,144;of the throat,143;prevalence of,142;pure food in,158;rest in,157;should be recognized early,157;sunshine in,158;why called the Great White Plague,142Typhoid fever, animals free from,113;carried by flies,80,81,116;carried by milk,22,117;effect of a single case,114;how germs leave the body,113;how germs get into the body,113;how germs get into water,114;importance of cleanliness,117,118;life of germs in a stream,115;recovered patient dangerous,117Umbrellas, necessity of,11Vaccination, cause of sore arms after,140,141;discovery of,132;how, prevents smallpox,135;necessity of repeating,137;pretended vaccination,138;when successful,138Ventilation, in homes,46,159;in public buildings,48,161;in workshops,48Veins,171Venous blood,171,172Villi,171Vitreous humor,178Voluntary action,181Water, avoid polluting,85–88,115;effect of sewage on,85,115;how germs get into,85–88;polluted, in milk,27;safe sources of,88Wells, how polluted,86,87;relation of toilets to,86,87Windows, should be kept open,45–47;should be screened,83Wood-ticks, as disease carriers,93;how abolished,94Wounds, importance of keeping clean,97Yards should be clean,77Yellow fever, how transmitted,92;how prevented,92
Adenoids,49,50
Air, amount necessary for health,45;effects of impure,45–48;fresh air, when needed,45–48;how secured,46,47;how changed in body,45;necessity of pure air,45–48
Air cells,175
Alcohol, effect of, on body,67–70;on brain work,70;on consumptives,69;on descendants,69;on liver,68;on morals,69;on nervous system,69;on powers of resistance,68;on stomach,67;false ideas about effects of,67;what business men think of,70
Alimentary canal,169,170
Amoebic dysentery, how prevented,122;how spread,122;where prevalent,122
Animals free from typhoid fever,113
Antitoxin, how it acts,108–110;how discovered,109;sometimes considered a poison,111;prevents diphtheria,110;saves lives,110
Aqueous humor,177
Arterial blood,172
Arteries,171
Articles used by the sick, dangers from,75;how to treat,76
Bathing, importance of,60;frequency of,60
Baths, hot,61;cold,61
Bedtime for children,51
Blood, arterial,172;how changed in the body,174;venous,171,172
Boils, how caused,95,99
Bones,163
Bronchi,175
Building foods,14,15
Candy, when harmful,54;when not harmful,54
Canned meats, why poisonous,32
Capillaries,172
Cells, are alive,6;body made of,6;body needs new,14;how killed,7;must not be killed,6;size of a,5;what they are like,5
Circulation of the blood,171–174
Clothing, effect of damp,11;promotes health,9;proper weight of,10
Common drinking cup,153
Consumption.SeeTuberculosis
Cooking, effects of improper,34,35;fatty foods,34;meats,35;starchy foods,34
Cornea,177
Coughing, dangers from,147,150–153;how to prevent dangers from,152,153
Cuspidors, in public buildings,152;pocket,152;street,152
Dairy, sickness about a,26,103,115
Decomposed foods dangerous,30,32
Decomposition, cause of,30;effect of cold on,31;of foods,30–32
Desserts, when harmful,40;when not harmful,40
Dining table, effect of dirty,37;cheerfulness at,37
Diphtheria, cure of,108–111;germs present after recovery,101,102;germs present when throat is not sore,104;how to confine germs,100;how poison is fought,108–110;mild cases, how detected,104;nature of the poison,108;prevalence of,100;where germs come from,100;why some cases are not quarantined,102–104
Dirt, a cause of sickness,77,78;getting into milk from cows,23,117;from cow barns,23–25;from milk cans and bottles,26,27;from milkmen,25;from flies,28,80,81
Diseased animals, effect on meats,19–21;effect on milk,28;tuberculosis from,28,155
Drafts, evil effects of,10;how to prevent harm from,10
Ear, care of,58;drum,179;inner ear,181;middle ear,179;outer ear,179
Esophagus,170
Excreta from sick, how dispose of,76,118
Exercise, necessity of,51,161
Eye, how germs get into,56;how overworked,57;method of testing,58
Far sight,58
Flies, breeding places for,77,80;as germ carriers,80,81,116;how to get rid of,82,83;how to keep out,83
Fly screens, where needed,83
Foods, advertised,16;building,14–16;decomposition of,30–32;heat-producing,14–16;improper cooking of,34,35;cost of suitable,16;uses of foods,14–17;uses of starches,14;uses of fats,15;value of meat as a,15;value of milk as a,14
Garbage cans, should be covered,83
Germs, cause of poison in meats,31,32;carried by dogs and cats,106;effect of, in wounds,95–99;how, get through the skin,95;how, get into the body,79;how, get into foods,79,80;how put into the air,147,150;how kept out of the air,151,152;how to fight,74;of lockjaw,98;man's greatest foe,1;nature of a,73;not alike,73;not killed by running water,115
Hair,169
Hearing, how tested,58
Heat, how kept up in the body,14
Hookworm disease, character of the worm,120;how it enters the body,121;how prevented,122;nature of the disease,121;where worm lives in the body,121;where prevalent,122
Insects that carry disease,92–94
Intestines,171
Iris,177
Joints,163
Larynx,174,175
Lens, the,178
Ligaments,165
Lungs,175
Lymphatics,171
Malaria, how transmitted,92;how prevented,93
Manure, a hatching place for flies,80,82;how to dispose of,82
Meal times, frequency of,53;regularity of,53;should be pleasant,37,38
Measles, after effects of,128;fatality of,128;necessity of care in,129;seriousness of,128;why to avoid,128
Meats, characteristics of good,18;Clean Meat League,19;from diseased animals,19–21;germs cause poison in,19,32;how kept clean,18;should be cooked,35;value of, as a food,18
Milk, as carrier of disease,22,117;effect of germs on,22;effect of disease in cow on,28;flies in,28;how germs get into,23–28;impure, dangerous,22;polluted water in,27;typhoid fever carried by,117;value of, as a food,14,20
Mosquitoes, as disease carriers,92,93;how to get rid of,94
Mouth, why some breathe through,49
Mouth-breathing, effect of,50
Muscles, attachment of,167
Nails, how to care for,61,62
Near sight,57
Nerves, compared to telegraph system,181;distribution of,181
Nose, importance of breathing through,48
Overcoats, necessity of,12
Overwork, effect of,51,52
Paper napkins for consumptives,152
Parties, time for,53
Pencils in mouth,155
Pharynx,175
Play a form of work,52
Playgrounds,161
Pocket cuspidors,152
Ptomaines,19
Quarantine, breaking, shows selfishness,126;how broken by family,105;rules of,105;seriousness of breaking,101;when safe to raise,102;why necessary,101;why some cases escape,102–104
Reflex action,181
Respiratory system,174–177
Rest, proper amount of,51
Retina,178
Rocky Mountain Spotted (Tick) Fever, how transmitted,94
Rubbers, necessity of wearing,11
Saliva, effect of, on starches,39,41
Salivary glands,170
Scarlet fever, a dangerous disease,124;mild cases dangerous,123,124
Scarlatina,125
Scarlet rash, why quarantine is necessary in,125
School lunches,37
Sclera,177
Sebaceous glands,169
Sewage, effect of, on water,85–87,115
Sickness about a dairy,26,103,115;due to germs, how prevented,3
Sick room, stay away from,75
Skin, care of,60,61
Smallpox, fatality of,131;how prevented,135–137;during Franco-Prussian War,132;in Sweden,133;in Gloucester,134;in the Philippine Islands,134
Spitting, dangers from,151;how avoided,152;where to spit,152,153;where not to spit,151
Springs, how polluted,87
Street cuspidors,152
Sunshine, effect of, on germs,77,78
Suppuration, how the surgeon prevents,96;how you may prevent,97;real cause of,96
Sweat glands, the work of,60
Teeth, brittle,42;dangers from poor,41–43;how to care for,43;necessity of baby teeth,41;uses of teeth,41;why, decay,42
Tendons,167
Tobacco, a poison,64;effect of, on blood,65;on heart,66;on nervous system,66;on nose and throat,65;on stomach,66;extra work caused by,64
Toilets, improper construction of,86;proper construction of,87;relation to wells,85–87
Tonsils,49,50
Trachea,175
Tuberculin test,155,156
Tuberculosis, can be prevented,142,148,157;fatality of,142;fresh air in,157,158;germ, discovery of the,145;how to get, out of a house,147,148;how germs leave the body,150,151;how spread from cows,28,155;how spread from the lips,153–155;how detected in cows,155;a house disease,146,147;not inherited,146;of the glands,144;of the joints,143;of the spine,144;of the stomach,144;of the throat,143;prevalence of,142;pure food in,158;rest in,157;should be recognized early,157;sunshine in,158;why called the Great White Plague,142
Typhoid fever, animals free from,113;carried by flies,80,81,116;carried by milk,22,117;effect of a single case,114;how germs leave the body,113;how germs get into the body,113;how germs get into water,114;importance of cleanliness,117,118;life of germs in a stream,115;recovered patient dangerous,117
Umbrellas, necessity of,11
Vaccination, cause of sore arms after,140,141;discovery of,132;how, prevents smallpox,135;necessity of repeating,137;pretended vaccination,138;when successful,138
Ventilation, in homes,46,159;in public buildings,48,161;in workshops,48
Veins,171
Venous blood,171,172
Villi,171
Vitreous humor,178
Voluntary action,181
Water, avoid polluting,85–88,115;effect of sewage on,85,115;how germs get into,85–88;polluted, in milk,27;safe sources of,88
Wells, how polluted,86,87;relation of toilets to,86,87
Windows, should be kept open,45–47;should be screened,83
Wood-ticks, as disease carriers,93;how abolished,94
Wounds, importance of keeping clean,97
Yards should be clean,77
Yellow fever, how transmitted,92;how prevented,92