6 INTRODUCTION 



been felt had Darwin left nothing but his 

 Origin of Species and the remarkable trea- 

 tises that followed it, but he has added thereto 

 leaders of thought of his own name and Hneage, 

 and they have carried his spirit and his breadth 

 of view into realms he could not himself enter. 

 The evolution of the earth and of the heavens 

 has thus felt his transmitted touch. The 

 concept of kinship of worlds follows eas- 

 ily on the concept of the kinship of organic 

 beings. 



In the transformed attitude of the intellectual 

 world to-day, the mooted question of the hour — 

 the evolution of the atom — ^finds a fair field, 

 wherein evidence needs but to accredit itself dxily 

 to have its place and weight freely accorded it. 

 If the atom shall show an authenticated pedigree, 

 it wiU easily take its place in the procession of 

 the derived, with the plant, the animal, the earth, 

 and the stars. 



The contributions of Darwin to the science 

 which it has fallen to me to f oUow have been great 

 and various, but the greatest of them aU relate 

 to the history of life on the globe. The geolog- 

 ical record, as known in his day, was at once a 

 foundation for his work and an obstacle to its 

 acceptance. It was the mission of his interpre- 

 tations to bring forth the added truth which made 

 the foundation broader and firmer, and which not 

 only removed the seeming obstacles in the evolu- 

 tionary path, but replaced them by cogent evi- 



