150 



Scientific Geology. 



dently washed from the region of argillaceous slate lying north, 

 through two or three narrow valleys, running north and south, down 

 which the current must have rushed with great force. Accordingly 

 we here find, on the road towards Northfield, a mile or two east of 

 Bernardston center, an example of diluvial elevations and depressions 

 scarcely equalled in the State ; exhibiting, as it were, the very gyra- 

 tions of the mighty torrent. But when this stream spread out over 

 the broad valley of the Connecticut, its violence and strength would 

 greatly diminish ; and hence this diluvium was not driven very far 

 into that valley. Yet at the east end of Mount Holyoke, where it 

 approaches the primary hills in Belchertown, we find a very power- 

 ful diluvial agency to have been at work, in consequence of the rush 

 of waters through the gorge between the mountains, and also through 

 the valleys on both sides of Mount Toby and among Pelham hills,to the 

 north. So that in the southeast part of Amherst, and indeed through 

 its whole eastern part, the diluvial sand and gravel are piled up and 

 scooped out in a striking manner. And in general, as we begin to 

 rise from the tertiary plain of the Connecticut basin, we find a greater 

 accumulation of this stratum than on the plain itself, or high up 

 among the primitive mountains. 



In passing over the mountainous region between the valleys of the 

 Connecticut and Berkshire, there is little in the character of the dilu- 

 vium worthy of special notice, till we approach the summit of Hoosac 

 mountain ; when we are surprised to meet with an immense number 

 of bowlders, which have been forced up the high and steep western 

 escarpment of that mountain from the valleys of Berkshire. In these 

 valleys, also, we find bowlders in abundance, which have been driven 

 over the Taconnic range from the State of New York. But these 

 facts will be examined more particularly farther on. 



Along the western base of the Hoosac range, diluvium is accumu- 

 lated in large quantities: but in general, this formation is not as abun- 

 dant to the west, as to the east of Connecticut river. 



As we pass from the Taconnic range to the Hudson, we find vast 

 accumulations of diluvium. The fragments decrease in size as we ap- 

 proach the river, and within a few miles of it, diluvial elevations and 

 depressions, composed of gravel and sand, are numerous and strik- 

 ing. The materials seem in part to have been derived from a terti- 

 ary formation, whose lower clay beds are still visible, a little east 

 of Troy and Albany. 



In Pownall, Vt. three miles north of Williams' College, is an un- 



