18 



Economical Geology, 



Although the granite in general, in the vicinity of Connecticut 

 river, is too coarse for architectural uses ; yet in Hampshire county 

 are several beds of a superior quality. Perhaps the best is found in 

 Williamson rgh, a few miles from Northampton. This rock, (some 

 of which may be seen in the front of a few buildings in Northamp- 

 ton,) very much resembles the granite found in the vicinity of Ded- 

 ham, and yields in beauty and value to none in the State. It exists 

 in abundance in Northampton, Whately, and Williamsburgh ; but 

 has yet been quarried only on a very limited scale. 



On the east side of the Connecticut, a very beautiful sienitic gra- 

 nite exists in Belchertown ; in which the mica, when the hornblende 

 is wanting, is very black. It is not surpassed in elegance by any 

 rock in the State ; but it has not as yet, to my knowledge, been quar- 

 ried at all. Indeed, very little real granite is employed in the middle 

 or western parts of the State, except in a rough condition. 



This sketch of the granite of Massachusetts, although brief, is suf- 

 ficient to show that we have a great number of varieties, and an ex- 

 haustless quantity, of this most valuable material for durable and ele- 

 gant architecture. Numerous varieties not mentioned above, which 

 have fallen under my observation, either in ledges or loose blocks, 

 will be found in the collection of specimens ; and some of these are 

 peculiarly beautiful. Numerous other varieties have doubtless es- 

 caped my observation. Indeed, we may safely assert, that no part of 

 the world is better furnished with this useful and indestructible rock. 



Gneiss. 



This rock is commonly known under the name of granite ; and, 

 indeed, it is composed of the same materials ; but in the gneiss, the 

 structure of the rock is slaty, and it splits in one direction better than 

 in others ; yet this slaty structure is often hardly perceptible, even 

 in wrought specimens ; and hence for all architectural and economi- 

 cal purposes, the distinction between granite and gneiss is of small 

 importance : though of much consequence in respect to the science 

 of Geology. 



The quarries of gneiss in Massachusetts are perhaps even more 

 numerous than those of granite, though not in general so extensively 

 wrought. It forms an admirable building stone : and is in no res- 

 pect, that I know of, inferior to granite ; while the facility with which 

 it cleaves in one direction, renders it easier to get out and dress ; so 

 that it can be afforded at a less price. Accordingly we find that a 



