surface of the skin, as well as by means of
the lungs.

One needs no better proof that carbonic acid is formed on the surface of
the body, than the fact that after the body has been closely covered all
night, if you introduce a candle under the bed-clothes into this
confined air, it will be quickly extinguished, because there is too
much carbonic acid gas there, and too little oxygen.

We may hence see at once the evil of covering the heads of infants when
they lie down--a very common practice. The air, when pure, contains a
little more than 20 parts of oxygen, and a little less than 80 of
nitrogen. Breathing this air, as I have already shown, consumes the
oxygen, which is so necessary to life and health, and leaves in its
place an increase of nitrogen and carbonic acid gas, which are not
necessary to health, and the latter of which is even positively
injurious. But when the oxygen, instead of forming 20 or more parts in
100 of the atmosphere of the nursery, is reduced to 15 or 18 parts only,
and the carbonic acid gas is increased from 1 or 2 parts in 100, to 5,
6, 8 or 10--when to this is added the other noxious exhalations from the
body, and from the lamp or candle, fire-place, feather bed, stagnant
fluids in the room, &c., &c.--is it any wonder that children, in the
end, become sickly? What else could be expected but that the seeds of
disease, thus early sown, should in due time spring up, and produce
their appropriate fruits?

It is sometimes said that fire in a room purifies it. It undoubtedly
does so, to a certain extent, if fresh air be often admitted; but not
otherwise.

I have classed feather beds among the common causes of impurity. Dr.
Dewees also condemns them, most decidedly; and gives substantial reasons
for "driving them out of the nursery."

In speaking of the structure of the room used for a nursery, I have
adverted to the importance of having a large or double room, with
sliding doors between, in order that the occupants may go into one of
them, while the other is being ventilated. But whatever may be the
structure of the room, the circumstances of the occupants, or the state
of the weather, every nursery ought to be most thoroughly ventilated,
once a day, at least; and when the weather is tolerable, twice a day. If
there is but one apartment, and fear is entertained of the dampness of
the fresh air introduced, or of currents, and if the mother and babe
cannot retire, there is a last resort, whi