Edward Livingston Youmans 65 



that it puts into definite and coherent shape the 

 ideas which many people are more or less vaguely 

 and loosely entertaining, and that it carries to a 

 grand and triumphant conclusion processes of rea- 

 soning in which many persons have already begun 

 taking the earlier steps. This community in men- 

 tal trend between the immortal discoverer and many 

 of the brightest contemporary minds, far from di- 

 minishing the originality of his work, constitutes 

 the feature of it which makes it a permanent acqui- 

 sition for mankind, and distinguishes it from the 

 eccentric philosophies which now and then come 

 up to startle the world for a while, and are pre- 

 sently discarded and forgotten. The history of 

 modern physics as in the case of the correlation 

 of forces and the undulatory theory of light 

 furnishes us with many instances of wise thoughts 

 floating like downy seeds in the atmosphere until 

 the moment has come for them to take root. And 

 so it has been with the greatest achievement of 

 modern thinking, the doctrine of evolution. 

 Students and investigators in all departments, 

 alike in the physical and in the historical sciences, 

 were fairly driven by the nature of the phenomena 

 before them into some hypothesis, more or less 

 vague, of gradual and orderly change or develop- 

 ment. The world was ready and waiting for Her- 



