22 A Century of Science 



of India might interest British students who might 

 have occasion to go there, but not Americans. 

 Such crude notions, utterly hostile to the spirit of 

 science, were unduly favoured fifty years ago by the 

 persistent unwillingness to submit the phenomena 

 of organic nature to the kind of scientific expla- 

 nation which facts from all quarters were urging 

 upon us. 



During the period from 1830 to 1860, the factor 

 in evolution which had hitherto escaped detection 

 was gradually laid hold of and elaborately studied 

 by Charles Darwin. In the nature of his specula- 

 tions, and the occasion that called them forth, he 

 was a true disciple of Lyell. The work of that 

 great geologist led directly up to Darwinism. As 

 long as it was supposed that each geologic period 

 was separated from the periods before and after 

 it by Titanic convulsions which revolutionized the 

 face of the globe, it was possible for men to ac- 

 quiesce in the supposition that these convulsions 

 wrought an abrupt and a wholesale destruction of 

 organic life, and that the lost forms were replaced 

 by an equally abrupt and wholesale supernatural 

 creation of new forms at the beginning of each 

 new period. But, as people ceased to believe in 

 the convulsions, such an explanation began to seem 

 improbable, and it was completely discredited by the 



