Applied Physiology Part 10

By means of the mind we feel, and know, and think. The mind uses each part of the brain for only one kind of work.

=142. The senses.=--The cells of the body send word to the brain over the nerves. The eye tells of sight, the ear of sounds, the nose of odors, the mouth of tastes, and the skin of feelings. All these messages go to the back part of the brain. They tell the mind of the news outside of the body. We get all our knowledge in this way. The cells also tell of their need of food and drink by means of the feelings of hunger and thirst.

=143. Motion.=--The mind in the cells of the top part of the head sends the orders for moving the different parts of the body. When we wish to run, the mind in the top of our head sends an order over our nerves to our legs, and they carry the body where we wish. If the top part of your brain is hurt, as by a blow, it cannot send orders to move, but you will lie stunned.

=144. Memory.=--The mind lays away all its messages, and often looks them over again. These old messages are called _memories_. They always stay with the brain, and the mind can call them up at any time. Our memories make our knowledge.

Every act of the mind leaves some mark on the memory. We may not be able to bring it back when we want to, but it will come back some time. Every bad word and evil deed will tend to come back and make us bad again. Every good work and word will leave its memory and make us better. We ought to fill our minds with good memories.

=145. Thinking.=--The brain also thinks. Thinking is different from feeling and from moving, but we can think about our feelings and about our movements. The brain just back of the forehead does all our thinking. A dog has only a little forehead, and cannot think much. But the rest of its brain is large, for it can see and hear and run as well as a man. A baby can see and hear and move, but it cannot think until it is taught how. Boys and girls go to school to learn to think.

Thinking is work, just as truly as running is work. At school, no one can learn to think without working. Looking at things and hearing some one talk about them will not make you a strong-minded man, but thinking about these things will. Boys and girls should study and think, as well as look around and listen.

=146. How thought rules the body.=--We are always feeling and moving.

We often do these things without trying, but we must make ourselves think. We can make our bodies move, or keep still, and we can keep from too much feeling. Our thoughts direct our natural desires to move and feel. In an animal, the feelings and movements direct the thoughts. When men let their feelings rule their thoughts, they are like animals. When the thoughts control the feelings and acts, we are men. If you get angry and cry, when you hurt your finger, then you are like an animal; but if you think about it and control your feelings, you are behaving like a strong and n.o.ble man. The thought part of the brain ought to rule all the rest.

=147. Sleep.=--Most of the brain does its work without our knowing it, but we know when we think. The thinking part of the brain gets tired, like any other part of the body. When it stops work, we are asleep.

We must give the brain a rest in sleep, just as we must rest an arm or a leg. We ought to give it regular rest. Every night we ought to go to bed early. Then we shall be ready to get up early and shall feel like working. Boys and girls need nine or ten hours' sleep each day. When they are grown, they need seven or eight hours' sleep each day.

The spinal cord and some parts of the brain must always stay awake to make the cells of the body eat and grow. When we are asleep, they must be wide awake, and must repair the worn-out parts. They do not seem to rest at all. If they rested for any length of time, then the lungs, heart, stomach and all other parts of the body would stop work, and we should die. But they really rest a part of the time. Like the heart, they act for a second, and then stop for a second. They seem to act all the time, but in all they rest half the time.

=148. Worry.=--The mind can do a great deal of work, if it gets good sleep. If a person gets enough sleep and rest, he cannot harm his mind by hard work. Sometimes the mind is troubled and worried over a danger or a loss. Then it cannot rest, but soon wears itself out. Worry is far more tiresome than hard work. By an effort, we can keep from worrying. It never does us good to worry, and we ought to keep from it.

=149. Nervousness.=--The thoughts are able to rule all the rest of the mind. They can keep us from feeling ill-tempered when we cannot have our own way. Sometimes a little unpleasant feeling makes us very unhappy, and keeps us from thinking about our work. A little noise or pain keeps some children from study, while others can bear a great deal without being disturbed by it. Some persons jump at a little noise, and are afraid of a tiny bug or mouse. This is because their feelings rule their thoughts. Such persons are called _nervous_.

A nervous person is very uncomfortable and makes others so too. Yet any one can get over the habit of being nervous, if he will try. You ought not to laugh at a nervous person if he is afraid of some little thing while you are not. You should help him to get over his nervousness and to become brave.

=150. Fear.=--Some persons are always brave. In danger they calmly stop to think, and then know how to save themselves. A timid person does not think, but rushes where his feelings lead. When a crowd is in danger, all will rush to do one thing. All will run for a door, and perhaps tread on one another. Then some one will surely be hurt. At a fire, or in any other danger, you should always stop to think how to act. If you rush with the crowd, you may be hurt. You will be more likely to be safe, if you stay away from them. Then, if help comes, you will be able to receive it. Besides, if you are cool and brave, you will help others around you to be brave too.

=151. Fire drill.=--In schools the children are taught how to go out of the building when there is a fire. A bell is struck when the children do not expect it. Then every child must leave his seat at once and march out of the building. The bell is struck every few days.

Then, when the bell really sounds for a fire, the children know how to march out quickly, and so they learn to be brave.

By training we can learn to be brave at all times. We fear many harmless things, and in many cases do not fear real dangers. We are liable to be hurt at any time. We are more liable to be hurt by a horse when we are out driving than we are by the dark. Yet we do not fear the horse, while some do fear the dark. We ought to learn to think, so as to control our fear.

Some are afraid of the dark, some are frightened by ghost stories, and others expect to see a wild animal jump from behind every bush. No one fears these things unless he has been told about them. We ought to be careful not to tell children of these things. We ought to teach them to control their fear.

=152. Habit.=--After we have thought about a thing a few times, its hold on our memory becomes strong, and leads us to think about it often. When we have done a thing a few times, we are likely to do it again without knowing it. We call this doing things over again _habit_. When we once form a habit, we find it very hard to break. We can form habits of doing right or of doing wrong. We can get into the habit of swearing or of drinking by doing these things a few times.

Then we shall do these things when we do not want to. When a drinker begins, he does not expect to keep on drinking. But his habit makes him drink, and he cannot help it. We should be careful not to do bad things, for we easily form the habit of doing them.

=153. Good habits.=--We can form habits of doing right. We can speak kindly and be generous. Then we shall do these things as easily as others get cross. After a person has tried to do good a few times, he will find it much easier to do good. Then he will speak kindly and give generously just as easily as others get angry and keep their good things to themselves.

=154. Alcohol takes away thought.=--Alcohol affects and weakens the cells of the brain sooner than it does those of any other part of the body. It first makes the thought cells weak. Then a person does not think how he acts. He lights his pipe in the barn and throws the match in the hay. He drives his horse on a run through a crowded street. He swears and uses bad language. He gets angry at little things and wants to fight. He seems to think of himself, and of no one else. He is happy, for he does not think of the bad effects of the drink. He has a good time, and does not care for its cost. He likes to drink, because it makes him feel happy.

=155. Alcohol spoils motion.=--Some cells of the brain cause the arms and legs, and all other parts of the body, to move. Alcohol next makes these weak. Then a person cannot move his legs right, but he staggers when he walks. He cannot carry a full cup to his lips. His hands tremble, and he cannot take care of himself. He is now really drunk.

=156. Alcohol takes away feeling.=--After a man is drunk, he loses the sense of feeling. He does not feel cuts and blows. Because he does not feel tired, he feels very strong. He often sees two things for one, and hears strange noises. The whole brain at last gets weak, and cannot act. Then the drinker lies down in a drunken sleep, and cannot be waked up. Some die in this state.

=157. Insanity.=--When the brain is misused by alcohol for some time, it cannot get over it. Then the person becomes insane. Drink sends more persons to the insane asylum than all other causes put together.

=158. Delirium tremens.=--If a drinker gets hurt, or becomes sick, he sometimes has terrible dreams. In them he sees dirty and savage animals coming to harm him. These dreams seem very real to him, and he cries out in his fright. This is called _delirium tremens_. A person is liable to die from it.

=159. Alcohol harms a drinker's children.=--The children of drinkers are apt to be weak in body and mind. A drinker hurts his children even more than he hurts himself. They are liable to catch diseases, and are often cross and nervous, or weak-minded. It is a terrible thing for a man to make his children weak and nervous.

=160. Other bad things about drink.=--There are many other terrible things about drink, besides the harm it does a man's body. Many a man has made himself drunk so as to steal or kill. No man can drink long without becoming a worse man for it. Men will not trust him, and he loses the respect of his friends.

Making strong drink takes thousands of men away from good work. They might work at building houses, or raising grain, or teaching school.

As it is, their work is wasted.

A great deal of money is wasted on strong drink. All the mines of the world cannot produce enough gold and silver to pay the drink bill. The people of the United States pay more for strong drink than for bread.

The price of two or three drinks a day would amount to enough, in ten years, to buy a small home.

The cost of strong drink is made much greater if we count the cost of jails and insane asylums. Over one half of all crimes and cases of insanity are caused by strong drink.

We must also add the misery and suffering of most children of drunken fathers. This loss cannot be counted in money. Numbers of children become truants from school and learn theft and falsehoods from lack of a father's care. When all the cost is counted, nothing will be found so expensive as strong drink.

On the other hand, what do people get for their money and suffering?

They get only a little pleasure, and then they are ashamed of it. Men use strong drink only because they like it more than they dislike its bad effects.

Since drink does a great deal of harm, with no good to any one, it is right to make laws to control its sale.

=161. How tobacco affects the brain.=--Some men smoke to make themselves think, and some to keep themselves from thinking. Now, smoking cannot do both things. It really makes the brain less able to think, for it weakens the whole body. A school-boy's brain will surely be harmed if he uses tobacco at all.

WHAT WE HAVE LEARNED

1. The mind makes all the cells of the body work together.

2. Tiny nerve threads carry messages from the mind to the cells.

3. Most of the nerves begin at the spinal cord in the backbone.

4. The mind in the spinal cord tells the cells to eat and grow.

It tells the arteries how much blood to carry to the cells.

5. The cells tell the spinal cord if they need food, or if something suddenly hurts them. The spinal cord sends word to s.n.a.t.c.h the part from danger.

6. Nerves carry to the brain news of sight, sound, odor, taste, and touch.

7. The brain sends word to the muscles to move the arms, the legs, and the rest of the body.

8. The brain thinks.

9. The brain stores up all its messages; these make memory and knowledge.

10. The thought part of the brain can control the feelings and the movements of the body.

11. Alcohol is more harmful to the brain than to any other part of the body.