Glacial Geology in America. — FaircJiild. 163 
tended paper by the latter described the glacial phenomena 
in the Alps, and stated that those of the White mountains were 
similar. The diluvialists still opposed the glacier theory, even 
to the degree of questioning the Alpine observations of Guyot 
and Agassiz. James Hall evidently voiced the sentiments of 
the younger men when he said, as reported in the discussion : 
"In this country there has been a tendency to oppose the glacial 
theory because it had been applied for the explanation of diluvial 
phenomena. We ought to be ashamed in this country, he said, to 
speak with confidence, after so little research, when there had been so 
much abroad." 
From this time there are fewer references to the origin of 
the drift. A new generation of geologists was taking the place 
of the older men and they were freer to accept the new ideas 
while not aggressively attacking the prevailing ones. The 
writings of the younger men frequently refer to glacial agency 
as an admitted fact. Among the contributions to glacial geo- 
logy in those earliest years of the science but very few can be 
noticed. In 1850 C. B. Adams, at the New Haven meeting of 
the Association, read a paper on changes of level in North 
America, in which, adopting the hypothesis of Lyell, he sug- 
gested the elevation of northern land as sufficient cause of the 
ice sheet; also of submergence at the close of the glacial period 
to account for the undisputed marine deposits. This hypoth- 
esis was elaborated by Dana in his presidential address of 1855, 
and placed upon a working basis by three time divisions: (i) 
Glacial epoch, with northern elevation of land; (2) Laurentian 
epoch, of depression; and (3) Terrace epoch, of moderate 
reelevation to present altitude. From this time Dana was the 
leader of the glacial forces and the chief exponent of the 
theory. 
In 1857 Edward Hitchcock published in the Smithsonian 
Contributions his extended and valuable paper ori Surface 
Geology, treating chiefly of the Connecticut valley. He distin- 
guished local glacial strige from the general drift striae, and 
recognized moraines and other effects of local glaciers. In 
1859 C. H. Hitchcock made the same discrimination for New 
England in general. The Cjeology of Vermont, published in 
1861, while describing phenomena of local glaciers, attributed 
the common drift to icebergs. In 1863 the report of progress 
