30 Charles Bohert Ihirwin. 



ogist. To the leading thought of Lyell, that the geologic 

 past finds a sufficient explanation in the present state and 

 tendency of things, his various studies brought emphatic 

 confirmation. His essay upon " Coral Eeefs " provecl their 

 origin in surface water, and deduced the conclusion of wide 

 areas of oceanic subsidence. " If he had -written nothing 

 else," says Geikie, "this treatise would alone have placed 

 him in the very front of investigators of nature." If less 

 original, not less masterly were his works upon Volcanic 

 Islands and the Geology of South America. The latter 

 sovight, and not in vain, to prove the slow and interrupted 

 elevation of the South American continent within a recent 

 geological period. But it was in the relations of geology 

 to biology that the geological results of Darwin were most 

 revolutionary and important. His chapter in the "Origin 

 of Species " on the "Imperfection of the Geologic Kecord" 

 proclaimed upon the house-tops Avhat had before been only 

 whispered in the ear, and very timidly. He proved that, by the 

 very conditions of its formation, the geological record must 

 be intermittent and fragmentary. Hence, in its character 

 there was no argument, as generally assumed, against the 

 genetic continuity of species, but in such continuity a con- 

 clusive evidence of the record's incompleteness. 



In the meantime Darwin was brooding patiently over the 

 idea of natural selection which had been suggested to his 

 mind by the zoological phenomena of the Galapagos 

 Islands, and in 1844 he made known the outlines of his 

 theory to Lyell and Hooker. But he had not, apparently, 

 the slightest disposition to take the general public into his 

 confidence. Another seven years went by, and still another, 

 and found him still making experiments, still collecting 

 facts, still trying to anticipate all possible objections. " He 

 that believeth shall not make haste " ; and Darwin might 

 have gone on for another twenty years thinking and prob- 

 ing, but for the fact that in 1858 Mr. Alfred Wallace sent 

 him an essay, based upon personal studies of the Malay 

 Archipelago, which was no more nor less than an expression 

 of Darwin's own most characteristic thought. This essay 

 Avas soon after published, jointly with extracts from Dar- 

 win's exposition of 1844 ; and, soon after, Lyell and Hook- 

 er persuaded Darwin to publish his own views more fully, 

 and this he did in 1859, when he was already fifty years of 

 age. This publication was the famous " Origin of Species," 



