GENERAL CONCLUSIONS. 291 



submerged continental areas, and the greatest of these 

 analogues of Greenland was, no doubt, the Cordilleran 

 system of glaciers depicted in the map prefixed to this 

 chapter. 



It has been the practice of the more extreme glacialists 

 to attribute to their opponents the idea that all glacial 

 work is done by icebergs, whereas they should have known 

 that seas loaded with icebergs imply land covered with 

 snow and ice. Iceberg-work implies glacier-work. It is 

 these glacialists who have persisted in confounding the 

 work of land-ice, icebergs and field-ice, in mixing up the 

 earlier and later drifts, in neglecting the effects of the 

 great movements of elevation and depression which were 

 going on throughout the Pleistocene period, in omitting 

 to consider the effects of the comparatively rapid move- 

 ments of this kind which must have taken place from the 

 crust suddenly giving way under tension, in confounding 

 deposits obviously, from their structure and fossils, marine, 

 with glacier moraines, in quietly assuming for glaciers an 

 extension physically impossible, in neglecting to consider 

 the possibility of tracts of verdure inhabited by animals 

 on the margin of snow-clad hills and table-lands, in exag- 

 gerating the eroding and transporting power of glaciers, 

 and minimizing that of sea-borne ice, and generally in 

 misunderstanding or misrepresenting the glacial work 

 now going on in the arctic and boreal regions. These are 

 grave accusations, but I find none of tlie memoirs or other 

 writings of the current school of glacialists free from such 

 errors ; and I think it is time tliat reasonable men sliould 

 discountenance these misrepresentations, and adopt more 

 moderate and rational views. 



The facts indicate that there was an earlier and later 

 period of glacial action and dispersion of boulders, that 



