68 CHARLES DARWIN 



At the same time, Darwin had not been idle in 

 other departments of scientific work. Side by side with 

 his collections for his final effort he had been busy on 

 his valuable treatise upon Coral Reefs, in which he 

 proved, mainly from his own observations on the Keeling 

 archipelago, that atolls owe their origin to a subsidence 

 of the supporting ocean-floor, the rate of upward growth 

 of the reefs keeping pace on the whole with the gradual 

 depression of the sea-bottom. ' No more admirable 

 example of scientific method,' says Professor Geikie 

 forty years later, ' was ever given to the world ; and 

 even if he had written nothing else, this treatise alone 

 would have placed Darwin in the very front of investi- 

 gators of nature.' But, from our present psychological 

 and historical point of view, as a moment in the de- 

 velopment of Darwin's influence, and therefore of the 

 evolutionary impulse in general, it possesses a still 

 greater and more profound importance, because the 

 work in which the theory is unfolded forms a perfect 

 masterpiece of thorough and comprehensive inductive 

 method, and gained for its author a well-deserved repu- 

 tation as a sound and sober scientific inquirer. The ac- 

 quisition of such a reputation, afterwards increased by the 

 publication of the monograph on the Family Cirripedia 

 (in 1851), proved of immense use to Charles Darwin in 

 the fierce battle which was to rage around the uncon- 

 scious body of the ' Origin of Species.' To be c sound ' is 

 everywhere of incalculable value ; to have approved one- 

 self to the slow and cautious intelligence of the Philistine 

 classes is a mighty spear and shield for a strong man ; 

 but in England, and above all in scientific England, it 

 is absolutely indispensable to the thinker who would 



