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 relation to intelligence, moreover, has usually been much exaggerated by anthropologists; for intelligence depends on the rapidity and range of the acts of associative memory, and this in turn on the complexity of the neural processes.  Brains are, in fact, like timepieces in this respect, that the small ones work “excellent well” if they are good material and well put together.  Although brains occasionally run above 2,000 grams in weight (that of the Russian novelist Turgenieff weighed 2,012), the brains of many eminent men are not distinguished for their great size.  That of the French statesman Gambetta weighed only 1,160 grams.  It must be borne in mind also that there are many individuals among the lower races and among women having brain weight much in excess of that of that of the average male white.