Men who have no interest in selling beer, and have experimented with
it to find out whether it strengthens the body, say that beer should
never be used as a food. It often tends to weaken the body. Children
should never use beer at any time, and older people can sometimes
avoid disease by letting it alone.

PRACTICAL QUESTIONS

1. Which are the best meats for food?

2. Why should we not eat meat at every meal?

3. How should meat be cooked to make it most tender?

4. How is soup or broth made?

5. Name the best vegetables for food.

6. Name some good grain foods.

7. Of what use are fruits?

8. What can you say of the use of eggs?

9. How should eggs be cared for?

10. What can you say of the use of salt and pepper?

11. Why does tobacco satisfy hunger?

12. Of what value is beer for food?

CHAPTER V

HOW PLANTS SOUR OR SPOIL FOOD

=Germs, Microbes, or Bacteria.=--The dust and dirt of all sorts
contain thousands of tiny plants too small to be seen by the eye
without help. An instrument called a _microscope_ makes them appear so
large that their form and growth are easily studied. These little
plants are called _germs_ or _microbes_. They are also named
_bacteria_. They are so small that a million laid side by side would
not cover the head of a pin.

[Illustration: FIG. 16.--Bacteria or microbes found in water, dust,
and waste. They help change straw and other dead matter into food for
plants. Much enlarged.]

There are hundreds of different kinds of germs. Some are round like
little balls and others are the shape of tiny rods. Many of them which
look just alike act very different in growing. There are more than
twenty different kinds that grow in our bodies and cause diphtheria,
tuberculosis, and other diseases. We have measles and scarlet fever
because we have gotten these disease germs from some one else in whom
they were growing.

[Illustration: FIG. 17.--Mold which grew on moist bread in two days.
5, seed bodies breaking out of the sack; 1, 2, and 4, one of the seed
bodies after one, two, and four hours' growth. Much enlarged.]

Most germs feed on dead matter instead of our living bodies and make
it melt away or change into another form. An apple or a piece of meat
thrown out on the ground will soon change and become like the earth on
which it lies. The change, called decay, is caused by millions of
germs. The farmer's be