1870.] 203 [Shaler. 



those regions which most closely resemble in their present condition 

 the state in which this country was placed during the glacial period, 

 we may find a ready explanation of this fact. In Greenland, for 

 instance, although the glacial sheet covers the whole of the country 

 at a few miles back from the shore, it only comes down to the coast 

 in the valleys or fiords. It will be at once seen, as soon as the dis- 

 tribution of our drift is indicated on a good geological map, that the 

 greatest accumulation of it is about the mouths of our larger river 

 valleys. The accumulation, of which we find the remains in the drift 

 hills of this neighborhood and the islands of the harbor, is the prod- 

 uct of the stream which descended the Charles River valley. The 

 immense drift deposits of Long Island, New York, are the product 

 of the Housatonic, the Connecticut and the Thames glacial streams, 

 possibly also of that more gigantic glacier which swept down the 

 Hudson. It is evident that these local glaciers could have been in ex- 

 istence only- during the later part of the drift period. There was an 

 earlier time when the moving sheet swept over the whole shore line, 

 as is proven by the fact that every exposed ledge on the shore or on 

 the .islands beyond it, is scored by the glacial movement. The termi- 

 nal moraine during this time must have been far out to sea, and it is 

 probably to this first stage of the glaciation of this country that 

 we owe the formation of the broad submerged table land which borders 

 the whole northern coast of the United States for a width of over one 

 hundred miles. We owe to Professor Agassiz the recognition of the 

 probable glacial origin of this set of banks and shoals. 



If we extend our hasty survey beyond the New England shore to 

 the northward, we find many facts which are reconcilable with the 

 views here presented. The banks of Newfoundland are most likely 

 the great terminal moraines of the vast glacier which discharged the 

 snows of the greater part of the region drained by the St. Lawrence. 

 They bear much the same relation to that valley which the eastern 

 part of Long Island bears to the basins' of the Connecticut and of the 

 rivers to the eastward. 



The most difficult question which the geologist has to deal with in 

 connection with the drift beds, is that of the origin of Cape Cod. I 

 do not propose to undertake at present the discussion of the history 

 of this singular promontory. I will only venture the suggestion that 

 the main body of the cape has very likely a low axis of elevation 

 beneath it, connected in some way with those lines of disturbance 



