6. The trunk is hollow, and has two chambers, one called the cavity of the chest, and the other the cavity of the abdomen.
7. The chest contains the two lungs and the heart.
8. The abdomen contains the stomach, liver, and many other very important organs.
9. Is it not our duty to take good care of our bodies as we would of some nice present from a friend?
CHAPTER IV.
OUR FOODS.
1. We all know very well that if we do not eat we shall rapidly lose in weight, and become very weak and feeble. Did you ever think how much one eats in the course of a lifetime? Let us see if we can figure it up. How much do you suppose a boy eats in a day? Let us say two pounds. How much does he eat in a year? There are three hundred and sixty-five days in a year; 365 multiplied by 2 equals 730. So a boy eats a good many times his own weight in a year. How much would a person eat in fifty years?
2. Our bodies are composed of what we eat. If we eat bad food, our bodies will be made out of poor material, and will not be able to do their work well. So you see how important it is to learn something about our foods. We ought to know what things are good for us to eat, and what will do us harm.