110 EVOLUTION THE RESULT OF CHEMICAL FORCES. 



1st. Large cranium capacity is not an unvarying index of high 

 culture and intelligence ; but such culture and intelligence never 

 exist without the large averages of brain size. The case is like 

 this: strong and powerful machinery is necessary to drive the 

 mill ; but if the power is not sufficient to drive the machinery, 

 the mill will never run. The capacious brain that was given to 

 the human race from its very inception, so far as we can judge, 

 and w T hich is in notable contrast to that of every other large 

 sized animal, was a machinery that was absolutely necessary to 

 the w r orking out of any kind of civilization ; but it lay dormant 

 for untold ages, and only awakened in these later years under the 

 spur of over-population, or rivalry, or of some master spirit. In 

 all this the idea is unavoidably suggested of the original endow- 

 ment of mankind with a surplusage of mind material with an 

 organ far above the then existing needs of its possessor, and de- 

 signed for use only in long distant ages. 



2nd. There is a gap between the brain-capacities of the lowest 

 or most ancient races of men, and the highest known ape species, 

 that natural selection does not and never can fill. If the princi- 

 ples of Darwinian evolution had anything to do with the case, 

 we would have a right to expect that savage and primeval man 

 would be furnished w T ith a brain only a little superior in size to 

 that of the larger apes; whereas he has one nearly three times 

 larger, and but little inferior to that of races of the highest 

 culture. 



3rd. From the fact that whenever an adult European has a 

 cranium less than nineteen inches in circumference, or brain con- 

 tents of less than sixty-five cubic inches, he is invariably idiotic, 

 we say confidently that man could never have sprung by any 

 slow and ordinary evolutional gradations, nor probably by any 

 relationship whatever, from anthropoid apes ; because if he had, 

 he would, with lessening brain or other abnormal conformation, 

 according to the principles of reversion as exemplified in all de- 

 rived species, become ape-like instead of idiotic. But so far as 

 known there has never been a case nor an indication of any such 

 reversion. 



Throughout the whole race of the quadrumana, both living 

 and extinct, the foot is prehensile, the thumb being opposed to 



