nature seems to have reached the
limit of her materials in creating the human species. The development
of hands freed from locomotion and a brain out of proportion to bodily
weight are _tours de force_, and, so to speak, an afterthought, which
put the heaviest strain possible on the materials employed, and even
diverted some organs from their original design. A number of ailments
like hernia, appendicitis, and uterine displacement, are due to the
fact that the erect posture assumed when the hands were diverted from
locomotion to prehensile uses put a strain not originally contemplated
on certain tissues and organs. Similarly, the proportion of idiocy and
insanity in the human species shows that nature had reached the limit
of elasticity in her materials and began to take great risks. The
brain is a delicate and elaborate organ on the structural side, and
in these cases it is not put together properly, or it gets hopelessly
out of order. This strain on the materials is evident in all races
and in both sexes, and indicates that the same general structural
ground-pattern has been followed in all members of the species.

Viewed from the standpoint of brain weight, all races are, broadly
speaking, in the same class. For while the relatively small series of
brains from the black race examined by anthropologists shows a slight
inferiority in weight--about 45 grams in negroes--when compared
with white brains, the yellow race shows more than a corresponding
superiority to the white; in the Chinese about 70 grams. There is
also apparently no superiority in brain weight in modern over ancient
times. The cranial capacity of Europeans between the eleventh and
eighteenth centuries, as shown by the cemeteries of Paris, is not
appreciably different from that of Frenchmen of today, and the
Egyptian mummies show larger cranial capacity than the modern
Egyptians. Furthermore, the limits of variation between individuals in
the same race are wider than the average difference between races.
In a series of 500 white brains, the lowest and highest brains will
differ, in fact, as much as 650 grams in weight.

There is also no ground for the assumption that the brain of woman
is inferior to that of man; for, while the average brain of woman is
smaller, the average body weight is also smaller, and it is open
to question whether the average brain weight of woman is smaller in
proportion to body weight.[257] The importance of brain weight in
rel