of the processes by which they are made. As hunter he followed game,
which, when found, he chased, fought, and overcame in a struggle
perhaps desperate, while we shoot it at a distance with little risk or
effort. In warfare he fought hand to hand and eye to eye, while we
kill "with as much black powder as can be put in a woman's thimble."
He caught and domesticated scores of species of wild animals and
taught them to serve him; fished with patience and skill that
compensated his crude tools, weapons, implements, and tackle; danced
to exhaustion in the service of his gods or in memory of his forebears
imitating every animal, rehearsing all his own activities in mimic
form to the point of exhaustion, while we move through a few figures
in closed spaces. He dressed hides, wove baskets which we can not
reproduce, and fabrics which we only poorly imitate by machinery, made
pottery which set our fashions, played games that invigorated body and
soul. His courtship was with feats of prowess and skill, and meant
physical effort and endurance.

Adolescent girls, especially in the middle classes, in upper grammar
and high school grades, during the golden age for nascent muscular
development, suffer perhaps most of all in this respect. Grave as are
the evils of child labor, I believe far more pubescents in this
country now suffer from too little than from too much physical
exercise, while most who suffer from work do so because it is too
uniform, one-sided, accessory, or performed under unwholesome
conditions, and not because it is excessive in amount. Modern industry
has thus largely ceased to be a means of physical development and
needs to be offset by compensating modes of activity. Many
labor-saving devices increase neural strain, so that one of the
problems of our time is how to preserve and restore nerve energy.
Under present industrial systems this must grow worse and not better