p
should not be overlooked. The bed should be comfortable, and the room
should be cool, well ventilated, dark, and quiet. The inducing of sleep by
means of drugs is a dangerous practice and should never be resorted to
except under the direction of the physician.

*Effects of Heat and Cold.*--Heat and cold both have their effects upon the
nervous system. Heat increases the nervous irritability, while cold acts
as a natural sedative to the nerves. A nervous person is made more nervous
by an overheated atmosphere, but derives beneficial effects from exposing
the body freely to cold air and water. The tonic cold bath (page 273), if
taken with the usual precautions, can be used to good advantage in
diminishing nervousness. The taking of outdoor exercise in cold weather
is, for the same reason, an excellent practice.

*Effect of Emotional States.*--We have already noted the effect of certain
emotional states upon the digestion of the food (page 162). Emotional
states are also known to interfere with breathing and with the action of
the heart. Such effects are explained through the close relation of the
mind to the work of the nervous system in general. While certain emotional
states, such as fear, anger, melancholia, and the impulse to worry,
interfere seriously with the normal action of the nervous system, others,
such as contentment, cheerfulness, and joy, are decidedly beneficial in
their effects. How important, then, is the habit of suppressing the states
that are harmful and of cultivating those that are beneficial. From a
hygienic, as well as social, standpoint a cheerful, happy disposition is
worth all the effort necessary for its attainment.

*The Nervous Condition of Children* should be a matter of deep concern on
the part of both parents and teachers. In the home, as well as in the
school, the child may be "pushed" until the nervous system receives
permanent injury. Exhaustion of nerve cells is produced through too many
and too vivid impressions being made upon the immature brain. The child
should be protected from undue excitement. He should have the benefit of
outdoor exercise and should be early inured to cold. He should be shielded
from the poisoning effects of tea, coffee, tobacco, alcohol, and other
drugs. He should have impressed upon him the habit of self-control. He
should not be indulged in foolish caprices or whims, but should be taught
to be content with plain, wholesome food and with the simple forms o