LIFE OF JAMES DWIGHT DANA 



controversy is evident. Many others have contributed 

 largely to the establishing of the fact of the existence of 

 a North American ice-sheet and determining its limits, 

 chief among whom must be mentioned Chamberlin, Up- 

 ham, Hitchcock, Lewis, Wright, and others; but Dana 

 was their leader, not only in first embracing the idea, but 

 in abundant, painstaking, detail work on the phenomena 

 in New England. 



If time permitted, we might take up many other 

 subjects which he touched only to illuminate, subjects 

 which in his mode of handling showed that rare com- 

 bination of original thought and painstaking, detailed 

 work which characterized him in so remarkable a degree. 

 We can barely allude to his work on the vexed " Taconic 

 question," which he, assisted by Walcott and others, con- 

 tributed so largely to clear up ; also to his work on the 

 difficult question of metamorphism, to which he devoted 

 much thought and careful work in the field. 



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