Object Lessons on the Human Body Part 16

How much must you eat?--"Enough, but not too much."

How must you eat?--"Slowly."

How should your food be masticated?--"Thoroughly."

When must you eat?--"Regularly, but not too often."

When should you avoid eating?--"Just before bedtime."

What kind of air should you breathe?--"Pure air."

How should you sit, stand, and walk?--"Erect."

Why should you not eat too much food?--"Because, if I eat too much food, my stomach will have too much work to do in changing it into chyme."

Why should you eat slowly?--"That I may have time to masticate the food thoroughly."

Why should you masticate your food thoroughly?--"That it may be well prepared to enter the stomach."

Why should the food be well prepared to enter the stomach?--"Because, if it is not well prepared in the mouth, the stomach will have too much work to change it into chyme."

Why should you eat regularly, but not too often?--"Because the stomach needs rest, which it cannot have, if I eat too often."

Why should you avoid eating just before bedtime?--"Because, while I am asleep, the stomach cannot do the work of changing the food as it ought to be changed; because the stomach should rest with the other parts of the body."

Why should you breathe pure air?--"Because pure air helps to make pure blood, which the stomach needs to make it strong and healthy."

Why should you sit, stand, and walk erect?--"That the stomach may not be crowded out of its place, or pressed upon by other parts of the body."

In what way does tobacco hurt the stomach?--"It poisons the saliva and prevents it from preparing the food to enter the stomach."

What harm does tobacco do inside the stomach?--"It weakens the stomach and makes it unfit to change the food into chyme."

How will wise children treat tobacco?--"Let it alone. They will not chew, snuff, or smoke the vile weed."

Is alcohol food or poison?--"It is poison."

How do we know it is not food?--"Because it cannot be changed into blood."

How has this been proved?--"Alcohol has been found in the brain, and other parts of drunkards, with the same smell and the same power to burn easily which it had when it was taken into the mouth."

How do you know it is a poison?--"Because it does harm to every part of the body, beginning in the stomach."

What harm does alcohol do in the stomach?--"It hinders the stomach from doing its work; it burns the coats of the stomach; it destroys the gastric juice; it hardens the food, so that it cannot be dissolved by the gastric juice."

What does the stomach do with alcohol?--"Drives it out as soon as possible."

Where does the stomach send it?--"Into the liver."

Where does the liver send it?--"To the heart; and the heart sends it to the lungs."

What do the lungs do with the alcohol?--"They drive it out as soon as they can."

Where do the lungs send some of it?--"Through the nose and mouth, into the air."

What harm does the alcohol do in the breath?--"It poisons the air; it tells that some kind of alcoholic liquor has been taken into the stomach."

From what you have learned about alcohol, what do you think is the only safe rule to obey concerning cider, beer, wine, and all alcoholic liquors?--"I must not drink them, if I wish to have a strong and healthy stomach."

[Ill.u.s.tration: THE NERVOUS SYSTEM.--(From Walker's _Physiology_.)]

1. The large brain. 2. The small brain. 3. The spinal cord. 4, 5. Nerves.

PART XI.

FORMULA FOR THE LESSON ON THE NERVOUS SYSTEM.

1. My brain is a soft gray-and-white ma.s.s resembling marrow.

2. It is placed in a bony box called the skull; it is covered and held together by three coats or membranes.

3. The outer membrane is thick and firm; it strengthens and supports the brain.

4. The middle membrane is thick, and somewhat like a spider's web in appearance.

5. The inner membrane is a network of blood-vessels.

6. From the brain, white or reddish gray pulpy cords, called nerves, pa.s.s to all parts of the body. These nerves are of two kinds: nerves of feeling, and nerves of motion.

7. If I p.r.i.c.k my finger, a nerve of feeling carries the message to my brain; if I wish to move my finger, a nerve of motion causes my finger to obey my will.

8. Twelve pairs of nerves pa.s.s from the base of the brain: the first pair, called the nerves of smell, to my nose; the fourth pair, called the nerves of sight, to my eyes; the fifth pair, called the nerves of taste, to my mouth, tongue, and teeth. One pair pa.s.s to my face; another to my ears. The ninth, tenth, eleventh, and twelfth pairs to my tongue and parts of my throat and neck.[3]

9. The spinal cord is a bundle of nerves extending from the base of my brain, down through the whole length of my spine, or backbone. It is the largest nerve in my body.

10. From the spine, thirty-one pairs of nerves, called _spinal nerves_, pa.s.s to different parts of my body; some to the lungs, some to the heart, some to the stomach, some to the bones, and some to the muscles and skin.

11. If a nerve be destroyed it cannot carry messages to and from the brain.

Before filling a tooth, the dentist sometimes destroys its nerve.

12. If a nerve be pressed upon too long it cannot perform its duty. If I press upon the nerve pa.s.sing to my foot, I stop it from communicating with the brain; the foot loses its feeling, or, as I say, "is asleep."

13. If I drink alcoholic liquors, or snuff, smoke, or chew tobacco, my brain and nerves cannot do their work well; because alcohol and nicotine are very poisonous to the brain and nerves.

14. The brain must be supplied with good blood;