oing on
all the time, but we do not sweat so much when we are quiet and are not
too warm, and so the sweat dries up as fast as it is produced, and we do
not see it. Nearly a quart of sweat escapes from the skin daily.

(2) _Breathing through the Skin._--We breathe to a slight extent through
the skin. There are some lower animals which breathe with their skins
altogether. A frog can breathe with its skin so well that it can live
for some time after its lungs have been removed. Breathing is an
important part of the work of the skin, and we should be careful, by
keeping it clean and healthy, to give it a good chance to breathe all
that it can.

(3) _The Skin Absorbs._--The skin absorbs many substances which come in
contact with it, and hence should be kept clean. If the foul substances
which are removed in the sweat are allowed to remain upon the skin, they
may be taken back into the system and thus do much harm.

(4) _The Skin has Feeling._--When anything touches the skin we know it
by the feeling. We can tell a great many things about objects by feeling
of them. If we happen to stick a pin into the skin we feel pain. We are
also able to tell the difference between things which are hot and those
which are cold. Thus the sense of feeling which the skin has is very
useful to us.

(5) _The Skin Protects the Body._--The skin is a natural clothing which
protects us much better than any other kind of clothing could. It is so
soft and pliable that it cannot hurt the most delicate part which it
covers, yet it is very strong and tough.

SUMMARY.

1. The skin is the covering of the body. It has two layers, the outer,
called the cuticle, and the inner, called the true skin.

2. A substance called pigment is found between the two skins. This gives
the skin its color.

3. The true skin has blood-vessels and nerves, but the cuticle has no
blood-vessels and very few nerves.

4. In the true skin are glands which produce sweat, and others which
make fat, or oil.

5. The nails are really a part of the skin. They are firm and hard, and
protect the ends of the fingers and the toes.

6. The hair grows from the true skin. The hair is made soft and glossy
by oil from the oil glands of the skin.

7. The skin is a very useful organ. It removes waste matters, it
breathes, it absorbs, it has feeling, and it protects the body.

CHAPTER XVI.

HOW TO TAKE CARE OF THE SKIN.

~1. Uses of the Pores of the Skin.~--Many years