CHAPTER XII
THE SKIN AND BATHING
Parts of the Skin.—The skin is about as thick as the leather of your shoe. It is fastened to the muscles beneath with fine white threads like spider webs. This is called connective tissue because it connects the skin to the lean meat.
The skin is made of two layers ([Fig. 45]). The upper layer is formed of cells. This is named epidermis or scarfskin. The deeper layer is made largely of fine threads woven together. It is the true skin or derma. There is no blood in the scarfskin, but there is a network of blood tubes in the true skin. It is the crowding of these with blood that makes the skin look so red when we get hot or excited.
The Use of the Skin.—The skin has three chief uses. It protects the softer parts of the body from being hurt by rough or hard things which might touch it. It contains the organs of feeling. It helps keep the right amount of heat in the body.
Fig. 45 —A thin slice through the skin, showing sweat glands, a nerve, and blood-tubes. Much enlarged.
The top part of the skin is dry and dead. This gives better protection than if it were moist and tender. Particles of it are wearing out and dropping off while other bits are growing beneath to take the place of the worn-out parts. The more this top skin is pressed on and rubbed, the thicker it becomes. For this reason it is twice as thick in the palms of the hand and on the soles of the feet.
Scattered through the true skin are millions of tiny organs fastened to the ends of the nerve threads leading to the spinal cord and brain. These organs tell us when the skin is touched or when it is hot or cold or is being hurt.
The Pores and the Sweat Glands.—On a warm day the skin becomes wet with a salty fluid called sweat or perspiration. This flows from the tiny holes or pores in the skin. A good magnifying glass will show these pores arranged in rows on the ridges in the palm of the hand.
From each pore a tube leads down into the true skin to a coiled tube forming the sweat gland ([Fig. 45]). Sweat glands are present by the thousands in the skin of all parts of the body. They give out from one pint to a gallon of sweat daily. The more we work and the warmer the weather, the more the sweat flows.
There is a little waste matter carried out of the body by the sweat, but its chief use is to cool the body. It does this by passing off in the air and carrying the heat with it. In this way the body is kept from getting too hot in summer.
The Color of the Skin.—In the African race the color of the skin is black, in the Chinese it is yellowish, while in our race it is nearly white. The different hues are due to a coloring matter called pigment. This lies in the deep part of the scarfskin. Going out in the wind and sun causes more pigment to collect, and we say we are tanned. If the pigment collects in spots, it makes freckles.
There is no way of removing at once freckles or tan. They usually disappear in the winter. No powders nor any other kind of medicine should be taken to make the skin white and smooth. Such medicines may contain poison and are likely in time to hurt the body. The skin may usually be kept soft and smooth by washing well with soft water and good soap. If it becomes harsh or cracked, a little glycerine rubbed on after each washing may help it.
The Nails and their Care.—The nails are hardened parts of the epidermis. They are intended to prevent the ends of the fingers from being hurt and to give a neat appearance to the hand.
The ends of the nails should never be chewed or torn off, as this makes the fingers blunt and the flesh sore. They should be filed or cut neatly with the scissors so that they do not stick out beyond the ends of the fingers.
Fig. 46 —Photograph of hands showing at the right how the nails should appear, and at the left how biting off the nails makes the fingers blunt and sore.
Many boys and some girls spoil the appearance of their nails by letting a line of black dirt remain beneath them. A piece of a stick or a nail cleaner should be passed beneath the nails every time the hands are washed. If the fingers are much soiled, a stiff brush is useful in removing the dirt under the nails.
Fig. 47 —A slice through a hair in its sac. Much enlarged.
The Hair.—Some hair grows on nearly all parts of the body. It is much thicker on the head than elsewhere. Each hair grows from a little knob at the bottom of a tiny tube in the skin called the hair sac ([Fig. 47]). If hair is pulled out, another one will grow in its place if the knob at the bottom of the sac is not hurt.
One or two oil glands open into each hair sac and give out an oil to keep the scalp and hair soft. No other hair dressing is needed.
After thirty or forty years of age the hair begins to turn gray. No medicine will prevent the hair from turning gray, and it is generally unwise to color the hair with a dye. There is poison in some of the mixtures sold to color the hair.
The Care of the Hair.—When the hair is uncombed, the whole person looks untidy. The hair should be combed carefully every morning and again made tidy before each meal. You should use as little water as possible to moisten the hair. The glands can be made to give out their hair oil by squeezing parts of the scalp between the fingers.
The scalp should be well cleansed with soap and warm water every three or four weeks. The hair should be dried quickly with a soft towel and by sitting in the sun or near a stove. One is likely to catch cold by going out of doors when the hair is wet. Hair oils and dandruff cures should not be used unless advised by a physician. Pinching and wrinkling the scalp twice weekly with the fingers makes the blood tubes grow larger and bring more food to the hair. It will also in many persons stop the hair from falling out and prevent dandruff and itching.
Fig. 48 —Photographs showing how keeping the hair tidy improves the appearance.
Do not use the hair brush of another person or exchange hats with your companions. Unclean persons and those living or playing much with them often have among their hairs little creatures called head lice. They suck blood and cause constant itching. The doctor will tell any one how to get rid of them easily.
Keeping the Skin Clean.—The amount of dead matter carried out by the sweat on to the skin every day is equal to a mass as large as your thumb. Dust also works through the clothing and sticks fast to the moist skin. For this reason every one should wash the whole body once or twice each week. The feet should be washed oftener as they become more soiled.
Many persons take a bath every day. A cold bath taken just after rising in the morning wakes up the nerves, makes the heart work better, and gives health and strength to the whole body. Afterward, the body should be well rubbed with a coarse towel. The bath may be taken by lying in a tub of water or by rubbing the body over quickly with a wet sponge. A hot bath is best for cleansing the skin. A warm bath makes one sleepy and should, therefore, be taken only at bedtime.
The hands should always be well washed before handling food. Persons neglecting to do this have caused much sickness because of the disease germs on their hands. One hundred and fifty persons were given typhoid fever in one city in Massachusetts by a man who handled milk without washing his hands. Dirt and disease are companions. You must be clean if you would be healthy.
The Kidneys.—The sweat glands do not take out of the blood one quarter as much waste matter as the kidneys. These are two bodies longer than the finger and more than twice as wide, and having the shape of a bean. One lies on either side of the backbone below the liver.
The blood coming to the kidneys is full of waste and dead matter picked up from all parts of the body. This is passed out through the thin walls of the thousands of little blood tubes into the many tiny tubes of the kidneys.
Fig. 49 —The blood tubes in a piece of skin as large as the head of a pin.
Water is required to keep the body clean within as well as without. For this reason you should drink more than a quart of water daily. A glass or two of water drunk a half hour before meals cleanses and rouses to action the digestive organs.
Alcohol and the Skin.—The skin of those who use much beer or whisky often becomes rough, red, and pimply. Any alcoholic drink is likely to injure the skin because it may hinder good digestion. The drunkard has a red nose and a dark-colored skin. This is because alcohol weakens the walls of the blood tubes and lets them become gorged with blood.
If a person takes a drink only once in a while, his face becomes red after each drink, and an hour or two later the effect of the alcohol passes off. The blood tubes have squeezed up to their natural size.
Alcohol and the Kidneys.—Taking several glasses daily of even such weak alcoholic drink as beer often causes the kidneys to become sick. Some of their working parts become changed to fat and some parts become hard. The cells which let the waste matter pass out of the blood get hurt by the poison of the alcohol so that they let some of the food also pass out of the blood.
PRACTICAL QUESTIONS
1. Name the two parts of the skin.
2. Give the three uses of the skin.
3. What is a sweat gland?
4. How much sweat is formed daily?
5. Of what use is the sweat?
6. How should the nails be cared for?
7. Tell what care should be given the hair.
8. Why should you not use another person's hair brush?
9. Why should the skin be washed often?
10. Of what use is a cold bath?
11. Why should the hands be well washed before handling
food?
12. Why does the drunkard have a red nose?