rushing. Hair oils are seldom
needed. If the skin of the head is kept in a healthy condition, the hair
requires no oil.

~10.~ The habit of biting and picking the fingernails is a very
unpleasant one, and keeps the nails in a broken and unhealthy condition.
The nails should be carefully trimmed with a sharp knife or a pair of
scissors.

~11. Effects of Narcotics and Stimulants upon the Skin.~--Alcohol,
tobacco, opium, and all other narcotics and stimulants have a bad effect
upon the skin. Alcohol often causes the skin to become red and blotched,
and tobacco gives it a dingy and unhealthy appearance.

SUMMARY.

1. If the pores of the skin are closed, a person will die.

2. We should bathe often enough to keep the skin clean.

3. We should not keep our rooms too warm, and should avoid wearing too
much clothing.

4. Alcohol, tobacco, and other stimulants and narcotics injure the skin.

CHAPTER XVII.

THE KIDNEYS AND THEIR WORK.

~1. The Kidneys.~--The kidneys are among the most important organs of
the body. They are in the cavity of the abdomen, near the back-bone, up
under the lower border of the ribs. Perhaps you have seen the kidneys of
a sheep or a hog. If you have, you know very nearly how the kidneys of
our own bodies appear.

[Illustration: KIDNEY.]

~2. The Work of the Kidneys.~--The work of the kidneys is to separate
from the blood certain very poisonous substances, which would soon cause
our death if they were not removed. It is very important to keep these
useful organs in good health, because a person is certain to die very
soon when the kidneys are in any way seriously injured.

~3. How to Keep the Kidneys Healthy.~--One way of keeping the kidneys in
good health is to drink plenty of pure water, and to avoid eating too
much meat and rich food. Pepper, mustard, and other hot sauces are very
harmful to the kidneys.

~4. Importance of Keeping the Skin Clean.~--The work of the kidneys is
very similar to that of the skin; and when the skin does not do its full
duty, the kidneys have to do more than they should, and hence are likely
to become diseased. For this reason, persons who allow their skins to
become inactive by neglecting to bathe frequently are apt to have
disease of the kidneys.

~5. Effects of Alcohol and Tobacco upon the Kidneys.~--A piece of beef
placed in alcohol soon becomes dry and hard, and shrivels up as though
it had been burned. The effect upon the kidneys of drinki