Grove Karl Gilbert: An Appreciation 



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analytical instincts and the far-sighted nature of his conclusions 

 are perhaps even better manifested in a number of his short- 

 er papers. In his contributions on isostasy, geologic time, 

 joints, fault-block mountains, and on the methods of scientific 

 investigation, he was clear, original, and convincing. His 

 presidential address before the Geological Society of America 

 in 1892, on "Continental Problems," was a paper remarkable 

 in comprehensiveness of view. In it he raised a number of 

 questions on important topics which geologists disregarded, 

 and showed himself twenty years in advance of his time in the 

 appreciation of the large significance of unconformities. 



