Valleys. 133 



hills and elevated ridges of less extent, occur in this valley ; but it is 

 unnecessary in this place to describe them. 



In tracing the Connecticut through this valley, the geologist will 

 be surprised to find it crossing the greenstone ridge above described, 

 and that too in its highest part, viz. through the gorge between Hoi- 

 yoke and Tom. For he will naturally enquire, why did not the river 

 flow through that part of the valley west of this ridge ; and follow- 

 ing the course of the Farmington Canal, empty at New Haven ? 

 For it appears from the surveys on that Canal, that in no place is that 

 part of the valley more than 134 feet above the present level of the 

 Connecticut at Northampton ; whereas the ridge through which it 

 passes is from 800 to 1000 feet high. But the surprise of the geol- 

 ogist will be still farther increased, when he finds this river at Mid- 

 dletown, quitting the great valley above described, and passing over 

 the remainder of its course through a deep ravine among primary 

 mountains. 



What inference shall we deduce from these remarkable facts? 

 Why, surely, that the Connecticut River did not excavate its own 

 bed ; for had the barriers at Northampton and Middletown been 

 higher than 134 feet, above its present bed, it must have emptied into 

 the Sound at New Haven. We must seek some other cause, there- 

 fore, for the origin of the passage between Holyoke and Tom, and 

 for that through the mountains below Middletown. 



Another inference is, that if the Connecticut ever formed a lake in 

 its present valley, it must have been rather limited and shallow. For 

 every place 100 feet higher than Northampton meadows at present,, 

 must have been above the waters. It may perhaps be thought that 

 a barrier might have formerly existed at New Haven, which was 

 subsequently worn down. But this would have been too mighty a 

 work for any transient deluge to accomplish ; and the idea that the 

 land was for a long time sunk beneath the ocean after the existence 

 of the river, so as to be acted on by currents, cannot be admitted, be- 

 cause this would have destroyed the river. The existence of an 

 extensive tertiary formation along the Connecticut, however, with 

 horizontal strata, renders it probable that this river did once form a 

 lake in its present valley ; though I have not been able to determine 

 certainly whether this tertiary formation was formed beneath fresh 

 or salt water. 



Not less remarkable than that of the Connecticut, are the beds of 

 its principal tributaries, the Deerfield, the Westfield, and the Farm- 



