92 Sketch of the Mineralogy 



considerably different from those of the iidjacent moun- 

 tain. 



They present very distinct crystals of feldspar, and 

 quartz in abundance,"^ but the mica, the other ingredient 

 of granite, is wanting, and we find little or no hornblende 

 so common in the contiguous whin stone mountain. 

 These are however some masses of compact, fine grained 

 black basalt lying upon the hill ; and upon the whole, 

 we must pronounce it grajiitic, although it is not granite, 

 and inclining to whin, although it is not whin stone. 

 It must be regarded as one of those masses which form 

 a connecting link between whin stone and granite, for it 

 must be remembered that granite, whin stone and por- 

 phyry graduate insensibly into each other. 



Leaving the East Mountain, and its dependencies, 

 we come next to that chain of high ground, which passes 

 immediately west of, and parallel to, the Hartford turn- 

 pike road, and terminates near the nev/ burying ground. 

 Here we shall not be detained long. The basis of the 

 hill appears to be a very coarse grained and friable red 

 sand stone. Upon its surface lie here and there, frag- 

 ments of granite, in many of which the feldspar is under- 

 going decomposition, and becoming porcelain clay. It 

 is, probably, from the decomposition of the feldspar of 

 granite, that the porcelain clay is principally formed. 



Most of that used in England is obtained from Corn^ 

 wall, where extensive hills or ridges of granite are now 

 undergoing decomposition. On the hill under conside- 

 ration, is found abundance of quartz, white, brown, and 

 red ; and masses of flint are not unfrequently met with. 



Proceeding in our survey, we arrive next at the 

 Pine Rock, lying north-v/est of the Beaver Ponds, 

 and east of the West Rock. Pine Rock is a mass of 

 Whin Stone, scarcely distinguishable in fracture, 

 grain and colour, from that of the East Mountain. It 

 contains however, veins of phrenite in radiated crystals, 

 and tremolite crystalized in diverging lines, grouped to- 

 gether like radii of a circle. It is somewhat gratifying 

 to find these crystalized substances, so common in the 

 whin of the old world, associated also with that of the 



