=The Senses of the Skin.=--There are endings of nerves in the skin all over the body. They are of three or four different kinds. Some of them tell us about heat, others tell us about cold. Some tell us about the shape, the smoothness, or hardness of objects, while others tell us when the skin gets hurt.

Most of the nerve endings are in the deeper part of the skin, so that they are covered by the epidermis and cannot be hurt by the rough things handled.

=Alcohol and the Senses.=--The senses are but little affected by a small amount of alcoholic drink. The sense of taste, after being accustomed to the sharpness of strong drink, may be less easily pleased with the taste of common food and drink.

The use of large amounts of alcohol blunts all the senses. In a drunken man the senses of the skin are so numbed that he does not know when anything touches him, and he may be badly burned before he feels the pain.

Heavy drinking makes the hearing less keen, enlarges the blood vessels of the eyes, and makes them appear red and bloodshot.

=Tobacco and the Senses.=--The use of tobacco does not injure the senses of the skin and usually has no effect on hearing. Both chewing and smoking, if much practiced, make the sense of taste less delicate, so that one cannot enjoy his food to the fullest extent.

Much smoking of tobacco may hurt the nerve of sight and in a few cases it has made men blind. Many boys have weakened their eyes by the use of cigarettes.

PRACTICAL QUESTIONS

1. Name the chief sense organs.

2. Of what use are the eyelids and tears?

3. Name four parts of the eyeball.

4. What is the iris?

5. Of what use is the lens?

6. What moves the eyeball?

7. When do children get weak eyes?

8. How are the eyes often hurt?

9. How may poor eyes be helped?

10. What makes the eyes sore?

11. How do germs get into the eyes?

12. Name the three parts of the ear.

13. What does the inner ear contain?

14. What may result from neglecting a sick ear?

15. Of what use is smell?

16. Why should food be well chewed?

17. In what part of the skin are most of the nerve endings?

18. What effect does tobacco have on the sense of taste?

CHAPTER XXIII

KEEPING AWAY SICKNESS

=Too Much Sickness.=--Many diseases are caused by our own carelessness and our bad habits of living. We have about one doctor for every one hundred families. There are enough people sick every day to make a city as large as New York or to equal the number of people living in the thirteen states of Idaho, Nevada, Wyoming, Arizona, New Mexico, Utah, Delaware, Montana, Vermont, New Hampshire, North Dakota and South Dakota, and Oklahoma.

A careful study of disease and its cause shows that at least one half of all the sickness in our land can be avoided by right living.

=The Cause of Sickness.=--Some people are so foolish as to make themselves sick. They weaken the body by using much beer or wine, by breathing bad air, by lack of exercise, or by fast eating. When the body becomes weak, it is likely to get sick at any time.

[Ill.u.s.tration: FIG. 93.--The germs of diseases. Much enlarged.]

It is not always our own fault when we are sick. It may be caused by the carelessness of others who have let germs escape from their bodies so that they are able to reach us. One half of the sickness in our land is catching sickness. That is, it is sickness which pa.s.ses from one person to another and is caused by tiny germs or microbes. A catching sickness is called a _contagious disease_. Some of the common catching diseases are sore throat, colds, diphtheria, pneumonia, typhoid fever, measles, grippe, and whooping cough.

=How we get a Catching Sickness.=--We get a catching sickness by taking into our bodies the germs from some other person. The germs of the sick do not pa.s.s off in the breath, but in the spit or anything else which comes from their bodies. This is why the spit and all slops from the sick room should be burned, buried, or destroyed in some way.

[Ill.u.s.tration: FIG. 94.--How the germs of disease start on their mission of death. This sewer carries slops from the houses of the sick and well and empties into a stream used below for drinking water.]

We should think it very wicked if a showman should turn his lions and tigers loose in a crowd of women and children. Somebody would surely be killed and others hurt. It is just as wrong to turn loose the germs of the sick by throwing the spit and the slops where they will get into a stream or where the flies may find them and by soiling their feet leave death in their trail wherever they crawl.

=How the Germs of Sickness catch Us.=--The germs of sickness have no feet to walk and no wings to fly, yet they easily travel from the sick to the well. They are not killed by being frozen, or drowned by floating in water, or destroyed by drying. For this reason they can travel with the ice, water, milk, and dust.

In Buffalo, New York, fifty-seven children caught the scarlet fever in one week by using milk cared for by a boy who was getting well from the scarlet fever.

The germs of sickness are so small that a million can hang to the hands or clothing and not be seen. For this reason they are often left clinging to the fingers, desks, books, and pencils, and travel in large numbers on the feet of flies. The surest way the germs have of getting from one person to another is by the common drinking cup.

[Ill.u.s.tration: FIG. 95.--Photograph of clear beef broth jelly in which a fly walked five minutes scattering germs. Two days later each germ brushed off the fly's feet grew into a city of germs appearing as a white spot.]

=The Common Drinking Cup is an Exchange Station for Germs.=--The most careful examinations have shown that there are thousands of children as well as grown persons who have very light attacks of scarlet fever, tuberculosis, or other diseases and go to school or about their work scattering the germs of sickness in their spit. A child seldom drinks from a cup without leaving on it thousands of germs. Some of these may be germs which will cause sickness. On one drinking cup used in a school, the germs were found to be as thick as the leaves on a maple tree in June.

In an Ohio school one warm day, a boy with beginning measles drank from the cup which was afterward used on the same day by the teacher and all the other pupils. In less than two weeks every pupil and the teacher were suffering from measles. _Put nothing into your mouth which has been in another's mouth._

[Ill.u.s.tration: FIG. 96.--A schoolhouse in Morgan county, Ohio, where sixteen pupils and the teacher caught the measles in one day by drinking from a cup which had been used by a boy sick with the measles.]

=The Golden Rule.=--If you have a catching sickness, such as measles, chicken pox, or whooping cough, stay away from others. Since the germs of some diseases, like scarlet fever and diphtheria, remain in the spit sometimes several months after you feel well, don't scatter your spit. Hold a handkerchief before your face when you sneeze or cough.

_Wash your hands before handling food._

=Some Animals carry Sickness.=--Mosquitoes carry malaria and yellow fever and some other diseases. Flies carry typhoid fever, grippe, diphtheria, and tuberculosis. Bedbugs and fleas carry the plague and leprosy. Rats carry the plague. Cats sometimes carry diphtheria. Many cows have tuberculosis and the germs of this disease are then sometimes found in their milk. Some children have caught tuberculosis from drinking such milk.

[Ill.u.s.tration: FIG. 97.--A pane of gla.s.s held about two feet before the face of a boy who sneezed. The spots are the droplets of spit thrown out. Each spot showed under the microscope from 50 to 1000 germs.]

=Keeping away Smallpox.=--Smallpox was once the most terrible of all diseases. It is so catching that two or three were often sick with it at one time in the same family. Sometimes nearly one half the people of a whole town would have the disease in one year. Over a hundred years ago nearly every grown up person had little pits scattered over his face as a result of having had smallpox.