ndition, and periodic visits at least once a year to a dentist's
office, not to the kind advertised by Indians where they are willing to
extract teeth without pain, free, but where a regularly qualified
dentist practices, should be the habit. Armenian children, who prize and
covet beautiful teeth, are taught to clean their teeth always after
eating, if only an apple or a piece of bread between meals, and while
probably our American customs would hardly make this possible, there is
no question but that a persistent and frequent use of the toothbrush
will help much in reducing dentist bills.

_Sleep._

From many standpoints sleep is the most wonderful attribute of the human
body. Our familiarity, from our earliest years, with sleep, closes our
eyes to its strange, its awful power. We know that every human being,
once in twenty-four hours, will normally close his eyes and for a
certain length of time be as oblivious to things present as if already
in the sleep of death. It is a common belief that sleep is nature's
provision for restoring tired muscles and jaded nerves, and for building
up new tissue in cell and corpuscle. Excessive exertion produces a
numbness and exhaustion so that the body becomes "dead tired," and sleep
brings back life and elasticity. And yet some parts of the body, some
muscles and some organs, do not stop work during sleep, and apparently
feel no bad results for their continuous lifelong exertion. Thus, the
lungs, whose muscular action is estimated at the rate of one thirtieth
of a horse power, have no rest day or night, seemingly without
weariness. Similarly, the heart is continually forcing blood under a
pressure of about three pounds through the arteries without cessation
from birth to death.

Why do the muscles of the arm and leg tire and need sleep as a restorer,
while those of the heart and lungs are independent of sleep? Dr. W. H.
Thomson, in his book on "Brain and Personality," finds an answer to this
question in the fact that the latter do their work independently of the
human consciousness, while the former are stimulated and directed by the
will. He points out that fatigue comes in proportion to the intensity of
the mental effort expended. A baby, to whom everything is strange, whose
consciousness is absolutely zero at birth, however well developed his
body, sleeps five sixths of the time because of the mental efforts
needed in his simplest bodily acts. Brain work, the most absorbing tas