anted in his lungs, he may have bronchitis or pneumonia. All these
kinds of sickness often spread from one person to another. If one person
in a family has a cold, others in the family often catch cold from him.

=215. Diseases like colds.=--Diphtheria, tuberculosis, whooping cough,
and measles all begin like a common cold and often look like a cold
during the whole sickness. Colds do not turn into any of these
diseases, for each of them comes from its own germ, just as corn comes
only from seed corn.

=216. Curing a cold.=--If you have a cold, you ought to stay at home
and rest, or lie in bed. Then your white blood cells can gain strength
to fight the disease germs. You ought to have plenty of fresh air in
your room. You ought not to eat much food for a few days, so that your
stomach and intestine and liver can use all their strength in throwing
off the poisons of the germs. But you ought to drink plenty of water,
so as to help wash away the poisons from your body.

=217. Keeping colds from spreading.=--You should keep away from other
persons while you have a cold, or other catching disease, so as to
keep from spreading the sickness. You ought not to go visiting, or go
to school, or to church, or to other meeting places. When you cough or
sneeze, you should hold a handkerchief to your mouth, so as to keep
from blowing disease germs from your throat and nose. You ought to
sleep in a bed by yourself, so that no one may take the disease germs
from your bedclothes. No one else should use your towel, or
handkerchief, or knife, or fork, or spoon, or dish, until they have
been washed in hot water, so as to kill the disease germs on them.

=218. Keeping from catching cold.=--You can keep yourself from
catching cold by keeping your body strong and in good order. You
should keep your clothes dry, eat good food, breathe pure air, get
good rest and sleep, and keep your body, your clothes, and your house
clean. You should also keep disease germs out of your body. You should
not form a habit of putting your fingers or a pencil to your mouth (p.
127). You should keep your nose, your throat, and your mouth clean.

=219. Cleanliness of the nose.=--The inside of the nose is wet with a
slippery liquid. If you have a cold, the liquid is thick and stops
your nose, and is called _phlegm_. The liquid catches and holds dust
and disease germs, and keeps them from going into the windpipe. It
also kills many of the disease germs.

You shou