24 A Century of Science 



abstruse the problem really was. Starting from 

 the known experiences of breeders of domestic ani- 

 mals and cultivated plants, and duly considering 

 the remarkable and sometimes astonishing changes 

 that are wrought by simple selection, the problem 

 was to detect among the multifarious phenomena 

 of organic nature any agency capable of accom- 

 plishing what man thus accomplishes by selection. 

 In detecting the agency of natural selection, work- 

 ing perpetually through the preservation of fa- 

 voured individuals and races in the struggle for 

 existence, Darwin found the true cause for which 

 men were waiting. With infinite patience and cau- 

 tion, he applied his method of explanation to one 

 group of organic phenomena after another, meet- 

 ing in every quarter with fresh and often unex- 

 pected verification. After more than twenty years, 

 a singular circumstance led him to publish an ac- 

 count of his researches. The same group of facts 

 had set a younger naturalist to work upon the 

 same problem, and a similar process of thought 

 had led to the same solution. Without knowing 

 what Darwin had done, Alfred Russel Wallace 

 made the same discovery, and sent from the East 

 Indies, in 1858, his statement of it to Darwin as 

 to the man whose judgment upon it he should most 

 highly prize. This made publication necessary for 



