Now what fuel must you use in your body-engine? In the first place you must put in fuel that will make the engine grow so that it can do a great deal of work. This fuel you get when you eat lean meat, eggs, milk, and many other things.
If you want your engine to keep warm, you must use fuel that will make heat. You get this fuel by eating plenty of fats, such as nice butter and some sweet things. Potatoes, rice and syrup help to run your engine.
You need some fuel that will make you plump and round and healthy looking, so you must put into your engine fruits, nuts, a little candy, and a lot of vegetables. You need to eat things that have color, such as: tomatoes, lettuce, greens, and beets,—not because they look pretty, but because they have iron in them and help to make your engine strong.
You must remember that you eat food for three reasons: to make you grow, keep warm, and able to work. You must be careful that you do not eat too much of any one kind of food, but remember to eat a little of many kinds. Your engine can use only a little of each at one time.
Wood is chopped into short pieces, and coal is broken up before it will do good work in the engine, so the fuel must be prepared before it will suit your engine. It must be well cooked and then chewed thoroughly before it will do its best work in your body-engine. You should be careful not to swallow any food until it has been chewed as fine as it can be.
If you put into your engine the right amount of food, and the right kind of well-prepared food, you will have an engine more wonderful than any steam engine that ever pulled a train, or carried a big ship across the wide ocean.
The engineer sees that his engine is kept clean and bright, in order that it may run smoothly. Since you are the engineer of your body-engine, you must keep it neat and clean that it may work well.
QUESTIONS
1. What is it that causes the big steam engine to do its work, draw long trains, or big ships, or turn great factory wheels?