Dewey on Geology of Williamstown, ^c. 341 



On these two hills, it lies in large strata, inclining, like the 

 mica slate, to the east and northeast, often divided bj veins 

 into rbomboidal masses. On the east side of Stone Hill, it is 

 more granular, and may perhaps be called arenaceous quartz, 

 containing a larger proportion of iron. Near the base of Hoo- 

 sack Mountain, similar quartz is found, which extends round 

 the north side of the Hoosack to Oak Hill, (D) which is 

 wholly composed of it. It lies in rounded fragments, called 

 hardheads, through the northern part of the valley, and on 

 the sides of Oak Hill in huge rocks, presenting nearly perpen- 

 dicular fronts from 20 to 50 feet in height, and many rods in 

 length. The strata are in some places horizontal, and in 

 others nearly perpendicular. In one place it forms plates, 

 from 2 to 6 feet on a side, and from half an inch to several 

 inches in thickness, which are nearly perfect rhomboids, the 

 edges never being perpendicular to the sides. Most of the 

 quartz, except the white, yields a small portion of lime, and 

 has been called calcareous quartz. Greasy quartz, rose quartz, 

 hornstone, and rock crystal, are occasionally found ; the last in 

 considerable quantity south of Stone Hill. On the stream 

 which issues from the Hopper, is arenaceous quartz of a slaty 

 structure, which is an excellent stone for sharpening the 

 chisels used by stonecutters. 



4. Granular Limestone is abundant at the Cave or Falls, in 

 Adams, and on both sides of the Hoosack. The Cave or Falls, 

 (O) is a singular chasm between limestone rocks. A small 

 stream, which appears once to have run on the surface of the 

 hollow between two small elevations, has now worn a passage 

 many feet in depth through the limestone. The chasm is nar- 

 row, winding in its course several rods long, and its opposite 

 sides were connected, till four years ago, by a natural bridge 

 of limestone. From the bridge to the water is 70 feet. There 

 is a dark cavern of several feet diameter, and some passages 

 into the rocks. The white marble walls, the foaming of the 

 water below, the piles and irregularity of the rocks, and the 

 thick overhanging trees, make the scene very wild and inter- 

 esting. The limestone rests on mica slate. On the west 

 bank of the Hoosack, and east base of the hill, (L) the same 



