i 4 THE POPULAR SCIENCE MONTHLY. 



heralded, quietly settled down to his work, and soon astonished 

 the world with the first published results, such as his book on 

 Coral Reefs, and the monograph on the Cirripedia ; and, finally, 

 how he presented his paper and followed it up with treatises 

 which make him one of the great leaders in the history of human 

 thought. 



The scientific world realizes, too, more and more the power of 

 character shown by Darwin in all this great career : the faculty 

 of silence, the reserve of strength seen in keeping his great 

 thought his idea of evolution by natural selection under silent 

 study and meditation for nearly twenty years, giving no hint of 

 it to the world at large, but working in every field to secure 

 proofs or disproofs, and accumulating masses of precious material 

 for the solution of the questions involved. 



To one man only did he reveal his thought: to Dr. Joseph 

 Hooker, to whom in 1844 under the seal of secrecy he gave a 

 summary of his conclusions. Not until fourteen years later 

 occurred the event which showed him that the fullness of time 

 had come, the letter from Alfred Russel Wallace, to whom, in 

 brilliant researches during the decade from 1848 to 1858, in Brazil 

 and in the Malay Archipelago, the same truth of evolution by 

 natural selection had been revealed. Among the proofs that sci- 

 entific study does no injury to the more delicate shades of senti- 

 ment is the well-known story of this letter. With it Wallace 

 sent Darwin a memoir, which he asked him to present to the Lin- 

 nsean Society ; on examining it, Darwin found that Wallace had 

 independently arrived at conclusions similar to his own possibly 

 had deprived him of fame ; but Darwin was loyal to his friend, 

 and his friend remained ever loyal to him. He publicly presented 

 the paper from Wallace, and with it his own conclusions, and the 

 date of this presentation July 1, 1858 separates two epochs in 

 the history, not merely of natural science, but of human thought. 



In the following year, 1859, came the first installment of his 

 thought in its fuller development his work on The Origin of 

 Species. In this, one at least of the great secrets at the heart of 

 the evolutionary process, which had baffled the long line of inves- 

 tigators and philosophers from the days of Aristotle, was more 

 broadly revealed. The effective mechanism of evolution was 

 shown at work in three ascertained facts: in the struggle for 

 existence among organized beings ; in the survival of the fittest ; 

 and in heredity. These facts were presented with such wealth of 

 minute research, wide observation, and patient collation, with 

 such transparent honesty and judicial fairness, that they at once 

 commanded the world's attention. It was the outcome of thirty 

 years' work and thought by a worker and thinker of genius, but 

 it was yet more than that it was the outcome, also, of the work 



