1 6 HISTORY OF CO II ASSET. 



places as to color the granite red by rusting, as may be 

 seen anywhere upon our rocks where the sea washes 

 them. 



The soda and the potash are less important. In fact, 

 the rock which is called granite has so many accessory 

 minerals besides the principal three that Zirkel, the min- 

 eralogist, has counted as many as forty-four. 



In the Whitney farm near the race track there is a 

 granite ledge which has become rotten by the rusting of 

 the iron in its crystals of black mica. The red sand of 

 this rotten granite has been used upon some of Mr. 

 Whitney's private roads. 



In different places of the town one can see that the 

 quality of the granite changes considerably. That, for 

 example, which may be seen in the great ledge at the 

 head of Depot Court has crystals very indistinct, much 

 of it with no crystals, just masses of felsite ; while there 

 is a ledge in Beechwood where the crystals are so large as 

 to be called giant granite or pegmatite. This ledge is on 

 the west side of Bound Brook (see the map;, a few hun- 

 dred feet from the schoolhouse, and is approachable from 

 Doane Street. The surface of the rock in places has 

 cavities shaped like the apex of a quartz crystal — three 

 broad sides and three narrow ones — some of the cuplike 

 places being as much as six inches in diameter. Instead 

 of the hornblende which is a principal element of our 

 quartz everywhere else, there is silvery mica here in thin 

 scales. This ledge is called The Reach, because it extends 

 so far out into the meadow and is one of our natural 

 curiosities. 



Between the two extremes of granite there are many 

 intervening grades of coarse and fine grains. It is rather 

 lighter in weight than Ouincy granite ; for a good speci- 

 men of the latter has a specific gravity of 2.669, while 

 this of ours is only 2.633. 



Neither is it so valuable for building as the Ouincy 



