es requiring mental concentration with
studies permitting motor activity, and arranging for very short
periods of the former. Anaemic children should be relieved of all
anxiety as to the results of their efforts, and only short hours
of daylight work required of them. The disastrous consequences of
eye strain should be understood by all in charge of children who
are naturally hypermetropic. The ventilation of a class room is
far more important than its decoration or even than a high average
percentage in mathematics, and the lack of pure air is one of the
auxiliary causes of nervous exhaustion in both pupils and
teachers. Deficient motor control is a most trustworthy indication
of fatigue in children, and teachers may safely use it as a rough
index of the amount of effort to be reasonably expected of their
pupils. Facial pallor or feverish flushes are both evidences of
overtasking, and either hints that fatigue has already begun. As
to unfavorable atmospheric conditions, the teacher herself will
undoubtedly realize them as soon as the children, but she should
remember that effort carried to the point of exhaustion, injurious
as it is in an adult, is yet less harmful than it is to the
developing nerve centers of the child.

Because adults at work and at play reluctantly submit themselves to
vitality tests, because few scientists are beseeching individuals to be
tested, because almost no one yearns to be tested, the promotion of
adult vitality and of community vitality can best be hastened by
demanding complete vital statistics. Industrial insurance companies and
mutual benefit societies are doing much to educate laborers regarding
the effect upon vitality of certain dangerous and unsanitary trades,
and of certain unhygienic habits, such as alcoholism and nicotinism.
Progress is slower than it need be because state boards of health are
not gathering sufficiently complete information about causes of
sickness and death. American health and factory inspection is not even
profiting, as it should, from British, German, and French statistics.
Statistics are in ill repute because the truth is not generally known
that our boasted sanitary improvements are due chiefly to the efficient
use of vital statistics by statesmen sanitarians.[7]

The vital statistics of greatest consequence are not the number of
deaths or the number of births, not even the number of deaths from
preventable diseases,