more elaborated than in childhood and often highly anesthetic and
disagreeable, motor cooerdinations that will need laborious
decomposition later. The avoidable factor in their causation is, with
some modification, not unlike that of the simpler feral movements and
faulty attitudes, carriage, and postures in children; viz., some form
of overpressure or misfit between environment and nature. As during
the years from four to eight there is great danger that overemphasis
of the activities of the accessory muscles will sow the seeds of
chorea, or aggravate predispositions to it, now again comes a greatly
increased danger, hardly existing from eight to twelve, that
overprecision, especially if fundamental activities are neglected,
will bring nervous strain and stunting precocity. This is again the
age of the basal, e.g., hill-climbing muscle, of leg and back and
shoulder work, and of the yet more fundamental heart, lung, and chest
muscles. Now again, the study of a book, under the usual conditions of
sitting in a closed space and using pen, tongue, and eye combined, has
a tendency to overstimulate the accessory muscles. This is especially
harmful for city children who are too prone to the distraction of
overmobility at an age especially exposed to maladjustment of motor
income and expenditure; and it constitutes not a liberal or
power-generating, but a highly and prematurely specialized, narrowing,
and weakening education unless offset by safeguards better than any
system of gymnastics, which is at best artificial and exaggerated.

As Bryan well says, "The efficiency of a machine depends so far as we
know upon the maximum force, rate, amplitude, and variety of direction
of its movements and upon the exactness with which below these maxima
the force, rate, amplitude, and direction of the movements can be
controlled." The motor efficiency of a man depends upon his ability in
all these respects. Moreover, the education of the small muscles and