Lately it has been learned in Germany that
tuberculosis causes one half of all the deaths among bartenders.
Alcohol was once thought to be a good medicine for lung troubles, but
it has been clearly proven that beer and whisky weaken the lungs and
make them ready for the germs of disease. The body already weakened by
the poison of the alcohol is then easily overcome by the disease.

=Tobacco and the Lungs.=--The occasional use of tobacco does not seem
to hurt the lungs when fully grown. A study of many young persons has
shown that the chest of smokers grows much more slowly than in those
who do not use tobacco. As the lungs cannot grow any faster than the
chest, they must grow slowly in boys using much tobacco.

Tobacco is a common cause of sore throat. Many smokers have been
compelled to quit the habit because of throat troubles.

PRACTICAL QUESTIONS

1. Where are the lungs located?

2. What do the tubes in the lungs carry?

3. What part of the air do we use in the body?

4. Tell how the air gets into the lungs.

5. What passes from the blood into the air sacs?

6. Why should we breathe through the nose?

7. Why should you keep the fingers away from the nose?

8. What are the vocal cords?

9. Give two reasons why no one should spit on the floor.

10. Tell how alcohol harms the lungs.

CHAPTER XV

FRESH AIR AND HEALTH

=How much Air we Breathe.=--At every breath we take in about one pint
of air. We breathe eighteen times each minute. Nine quarts of air
therefore pass in and out of the lungs every minute. Air once breathed
is not fit to breathe again. It contains waste and carbon dioxide
which weaken the body.

If you breathe three full breaths into a wide-mouthed jar or bottle,
it will contain so much of the carbon dioxide that a lighted candle or
splinter will at once go out when thrust into the jar. A cat shut in a
tight box two feet square and one foot high will die in less than a
half hour.

Many years ago when the British and Hindoo soldiers were fighting each
other, the Hindoos made prisoners of 146 of the British and locked
them in a room about one half as large as a common schoolroom. There
were only two small windows. During the night 123 of these men died
because of the bad air.

[Illustration: FIG. 64.--The direction of the flame of the candle
shows how the fresh air enters and the bad air leaves a room.]

=How much Air shoul