42 



Geology, i^'-c. of the Connecticut. 



a dip as represented by the parallel lines. Let C D be a 

 deposite of the coal formation 1} ing upon the old red sand- 

 stone, the strata of which have the same dip. Now, to 

 »n observer passing along the surface from A to D, the red 

 sandstone, between A and C, appears to lie upon the coal 

 formation between C and D, whereas, the reverse is the 

 fact. This might apply to the rocks we are considering in 

 Connecticut, were it not for what I think to be the fact, 

 that there is a gradual passage of the old red sandstone in- 

 to the coal formation. 



These, and some other circumstances, made me suspi- 

 cious, for a time, that this range of sandstone east of Con- 

 necticut river, might not be the real old red sandstone, but 

 a member of the coal formation ; — and it was not till I had 

 traversed it the third time, that I felt entirely satisfied. 

 But much of it certainly does not differ, at all as I could 

 discern, from the old red sandstone on the western side of 

 the river; and we find likewise the very same conglome- 

 rate. The strata also, are of a similar thickness and dip, 

 varying as to the form, from six inches to two or three 

 feet; and as to the latter from 10° to 30° ; usually, how- 

 ever, not more than 10°. This dip, in all the red sand- 

 stone of the Connecticut, is below the eastern part of the 

 horizon, with the single exception of a ledge that appears 

 in the west street of Hatfield, where the dip is to the 

 west. 



This rock is extensively quarried for the purpose of 

 building, in almost every town along the river. Noble 

 specimens may be seen in the vestibules of the churches in 

 New-Haven. 



