Many persons would like to break off the habit of drinking beer or whisky, of chewing tobacco, and using bad language, but they find it very hard to make the mind rule the body because they have let the nerves have their own way so long.

Speaking cheerfully to those we meet, giving a kind word to our friends, and looking pleasant are good habits which every one ought to form in youth. They not only make the mind better, but they help the body to keep well and will prepare the way for success in life later.

n.o.body wants a grumbling clerk or a sour-faced housekeeper.

[Ill.u.s.tration: FIG. 88.--The difference in appearance between a pouting and a pleasant expression.]

=Parts of the Body work without Orders from the Brain.=--A snake with its brain crushed will still squirm and a chicken with its head cut off jumps about. These movements are caused by orders sent from the spinal cord. When the hand or foot is being hurt, the spinal cord orders the muscles to draw the limb away even before we feel the pain in the brain. Many of the movements of the body which are often repeated may be directed by the spinal cord, while the brain is left free to do other work. This is why the spinal cord is called the helping manager.

The action of the muscles in the walls of the blood vessels, the working of the stomach, the liver, pancreas, and other glands are not directed by the brain, but by the _sympathetic nerves_. These extend from a little cord on either side of the backbone to all parts of the body and make the organs, such as the heart and sweat glands, which we cannot make obey our will, do their work.

=Injury to the Nerves.=--The nerves are so important for the welfare of the body that all the chief ones are placed deep in the flesh, where they are not likely to be hurt. If the nerves leading to the arm were cut, it could not be moved, and we should have no feeling in it.

The hurting of a part of the brain, the spinal cord, or the nerves may cause loss of feeling or motion in the leg, arm, or other part of the body. Such a part then seems asleep or dead and is said to have _paralysis_.

Pressing on a nerve prevents it from acting. Sitting so as to press on the nerve of the leg often makes the foot go to sleep. The bursting of a blood vessel in the brain may let a blood clot form and press on the nerves which govern the arm or the leg. This pressure may cause paralysis.

=Resting the Brain.=--When there is no food in the stomach, it has time to rest. When we sit down or lie down, the muscles get rest. The brain is always busy except when we are asleep. No one can live even a week without sleep. If a dog is kept awake five days, it will die.

[Ill.u.s.tration: FIG. 89.--Sleeping in the position shown in the lower figure prevents free breathing and tends to cause round shoulders. The upper figure shows correct position.]

Children need much more sleep than older persons. Men and women who work should have about eight hours of sleep daily to remain in good health. Children of twelve years should sleep nine hours each day; those of ten years, ten hours; those of seven years, eleven hours; and those of four years, twelve hours.

=Getting the most out of Sleep.=--You should go to bed every night at about the same hour. This will help you to fall asleep as soon as you are in bed. Do not sleep in the clothes which you have worn during the day, but hang them up to air, and put on a night robe.

Children should use a very low pillow, so that the body can lie straight in the bed. This gives the lungs and heart freedom to act. Do not lie on the back as this causes some of the organs to press on certain nerves and makes you dream. The windows should be opened wide because fresh air is the best aid to rest and health and keeps away tuberculosis.

PRACTICAL QUESTIONS

1. What makes the parts of the body work together?

2. Describe the surface of the brain.

3. Name the three parts of the brain.

4. Of what is the outer layer of the brain made?

5. Where is the spinal cord?

6. What are nerve fibers?

7. What work does the brain do?

8. What makes the mind good or bad?

9. What is habit?

10. How long should children sleep?

11. How can you get the most good out of sleep?

CHAPTER XXI

HOW NARCOTICS AND STIMULANTS AFFECT THE BRAIN AND NERVES

=What Narcotics and Stimulants Are.=--A _narcotic_ is something which when taken into the body makes the organs do their work more slowly and tends to cause sleepiness. Alcoholic drinks, tobacco, opium, soothing sirups, and pain killers are narcotics.

A _stimulant_ is a substance which makes the organs of the body do more and quicker work and does not later make the organs work more slowly. Coffee and tea are stimulants. Beer, wine, and whisky were once thought to be stimulants, but experiments have shown them to be narcotics. They urge the brain to faster work for a few minutes, but a half hour later they make it act slower than usual.

=Alcohol hurts the Brain.=--Within five minutes after a drink of beer or whisky has been swallowed, part of the alcohol has reached the blood. Within fifteen minutes much of the alcohol has gone from the stomach directly into the blood. In a minute after entering the blood vessels it reaches the brain.

If much strong drink is taken, the cells of the brain become so numbed that they cannot give the right orders to the muscles to move the limbs. The person then staggers about and is said to be drunk. Much whisky taken will make the nerve cells so numb that a man cannot move, and he will then lie down as if in a deep sleep.

A tablespoonful of whisky will make a child drunk and twice that amount may make him very sick. Much use of strong drink sometimes gives to the brain a terrible disease called _delirium tremens_. In this sickness the man thinks he sees horned animals, hissing snakes, and other creatures which annoy him.

=Alcohol injures the Thinking Part of the Brain.=--It was once thought that wine or whisky would make a man think better. Now we know that either of these drinks makes his thoughts slower and also causes him to make mistakes.

Two doctors in Europe made many tests with men to learn how alcohol affected their thinking. They found that when using wine the men could do about one tenth less work in adding numbers than when they took no strong drink. These doctors also tested the effect of alcohol on memory and discovered that the use of even small quant.i.ties of liquor caused their pupils to learn their lessons more slowly.

When persons have taken only a very little drink, they often say and do very foolish things. They sometimes tell secrets, for which they are very sorry when they get sober. Often they become angry at the least cause and strike or even shoot any person who seems to speak or work against them in any way.

=Alcohol makes People Steal and Kill.=--The alcohol in strong drink, when often used, appears to deaden that part of the brain which helps the mind know right from wrong. In one year the courts of Suffolk County in Ma.s.sachusetts found 17,000 persons guilty of doing some wickedness and in over 12,000 of these cases alcohol was found to be the cause of doing the wrong for which they were arrested.

Some time ago there were collected the records of 30,000 prisoners, and among these over 12,000 had done their wicked acts while alcohol was numbing the brain. Lately another careful record of over 13,000 prisoners in twelve different states has been studied. In over 4000 of these men the use of strong drink was the first cause of their crimes.

=Alcohol makes the Mind Sick.=--Since the mind depends upon certain parts of the brain, whatever hurts the brain is quite sure to hurt the mind. When the mind cannot reason rightly, the person is said to be _insane_. A study of 2000 insane men in New York State showed that the use of alcoholic drink was the cause of the mind sickness in over 500 of them. Of 687 persons in Ma.s.sachusetts who were so insane that they had to be cared for daily by others, more than 200 of them were brought to this sad condition by alcohol.

=Brain of the Young easily overcome by Alcohol.=--No one expects to become a drunkard or a criminal when he first begins to drink. The continued use of alcohol, however, soon numbs the brain and weakens the mind, so that the person's will power is lost. He is then not able to quit drinking even though he wants to stop. He has become a slave to alcohol.

_The brain of a young person is injured much more quickly by alcohol than that of an older person and he_ is much more likely to become a slave than one who begins the use of drink late in life. Doctor Lambert, of New York, studied the cases of 259 slaves to alcohol. He learned that four began to drink before six years of age; thirteen between six and twelve years of age; sixty, between twelve and sixteen years; 102 between sixteen and twenty-one years; seventy-one, between twenty-one and thirty years; and only eight after thirty years of age.

These facts teach that it is dangerous for the young to take strong drink at any time.

=Laws against Alcohol.=--The men who make laws for the good of the people are learning that alcohol is injuring the mind and body of many persons every year. For this reason laws have lately been pa.s.sed forbidding the sale of strong drink in several entire states and in large parts of many other states.

=Tobacco makes the Brain work Slower.=--An examination of the age and habits of hundreds of the students entering a large university in New England showed that those who smoked required more than a year longer than those who did not use tobacco, to learn enough to enter the first cla.s.ses in this school. Moreover, out of every hundred of those who took the highest rank in their work in the university, ninety-five did not use tobacco. It is likely that tobacco makes the mind work slower by preventing the full amount of blood from going to the brain. It does this by making the blood vessels smaller.

So far as known tobacco has but little effect upon the brains of older persons.

Superintendent Ogg of Indiana reports that the occasional users of cigarettes are a year, and the regular users two years, behind those who do not smoke. The conduct and honesty of the smokers were also found to be lower than among those who did not smoke.

=Opium, Morphine, and Cocaine.=--All of these harmful drugs are widely used in our country. They act on the brain in a strange way. All of them deaden pain. When a person first begins their use, only a small amount is required to produce the effect wanted on the body. Later the doses must be increased. After a few months' use the person becomes a slave to the habit of using them, and he cannot stop their use without the help of a doctor. It is therefore dangerous to use these drugs at any time.

Powders used for colds in the nose, also paregoric and laudanum, contain these harmful drugs.

=Pain Killers and Soothing Sirups.=--All pain killers contain opium or morphine or other harmful drugs. They are therefore dangerous to use.