al object; for all experience shows that, with a rational
distribution of employment and exercise, a child will make greater
progress in a given period than in double the time employed in
continuous mental exertion. If the human being were made up of nothing
but a brain and nervous system, we might do well to content ourselves
with sedentary pursuits, and to confine our attention entirely to the
mind. But when we learn from observation that we have numerous other
important organs of motion, sanguification, digestion, circulation, and
nutrition, all demanding exercise in the open air, as alike essential to
their own health and to that of the nervous system, it is worse than
folly to shut our eyes to the truth, and to act as if we could, by
denying it, alter the constitution of nature, and thereby escape the
consequences of our own misconduct.

Reason and experience being thus set at naught by both parents and
teachers in the education of their children, young people naturally grow
up with the notion that no such influences as the laws of organization
exist, and that they may follow any course of life which inclination
leads them to prefer without injury to health, provided they avoid what
is called dissipation. It is owing to this ignorance that young men of a
studious or literary habit enter heedlessly upon an amount of mental
exertion, unalleviated by bodily exercise or intervals of repose, which
is quite incompatible with the continued enjoyment of a sound mind in a
sound body. Such, however, is the effect of the total neglect of all
instruction in the laws of the organic frame during early education,
that it becomes almost impossible effectually to warn an ardent student
against the dangers to which he is constantly exposing himself. Nothing
but actual experience will convince him of the truth.

Numerous are the instances in which young men of the first promise have
almost totally disqualified themselves for future useful exertion in
consequence of long-protracted and severe study, who, under a more
rational system of education, might have attained that eminence, the
injudicious pursuit of which has defeated their own most cherished
hopes, and ruined their general health. Such persons might be saved to
themselves and to society by early instruction in the nature and laws of
the animal economy. They mean well, but err from ignorance more than
from headstrong zeal.

I shall conclude this chapter with a few rules rela