90 GIJEEN MOUNTAINS IN MASSACHUSETTS. 



the quartzite |nd connected with the crushing. The laminated quartzite is 

 closely underlain by curving outcrops of a rather coarse layer gneiss, in 

 which long flat bands of feldspathic material, blue quartz, and biotite 

 alternate. This again is conformably underlain by outcrops of tine-grained 

 biotite gneiss. These outcrops are separated a few feet horizontally. 

 Their contacts must be within a few inches of Strata, and they are perfectly 

 conformable. This proves the structural conformity of this massive quartzite 

 series with the underlying gneisses. A mile and a half north of this we 

 find the sharp point of the mountain, on the east side of which the valley 

 makes a bay or "cove" running a mile south. This "point" of the moun- 

 tain is formed by the massive quartzite, south to the crest, and also at its 

 north and west base, where the quartzite is quarried for sand, and the stream 

 makes a fine cut through it. One-eighth mile east of Cheshire village the 

 quartzite is quarried from a large mass, striking north 30 c west, dipping 20° 

 northerly, and can be followed southeast for at least one-quarter of a mile 

 with the same strike and dip. Along the west side of this point of the 

 mountain the quartzite has been quarried in several places. About 1 mile 

 south of Cheshire, near the north end of the pond, at a sand mine, the 

 quartzite strikes north 40° to 50° east, dips 20 c west, while northeast of here, 

 on the slopes of the mountain, near another old sand-mine, the strike is 

 north s<> west, dip 20° northerly. This "point" of the mountain therefore 

 represents an anticline in the quartzite, collapsed and overthrown to the 

 east — a prow, or inverted canoe. On the top of the crest of the mountain 

 the quartzite forms the slopes and highest crests, striking north 15° west, 

 dip 15° east; in the east slopes it strikes north 30° west, dips 30° east. 



Going back to the quartzite quarry, in a little ravine off the road, an 

 outcrop of calcareous quartzite is found overlain within 10 feet by an im- 

 pure limestone. The strike is about north 20° west, dip about 30° north- 

 east. A few hundred yards further north outcrops of limestone are found 

 striking north 50° west, dipping 45° east. It is to be noticed therefore that 

 the limestone also circles around the quartzite to the north anil strikes south 

 to lie east of the quartzite, forming in part at least the bay or "cove" of the 

 valley. No outcrop, however, of the limestone in place is found in this 

 cove. Tlu' southern rim of the cove is formed by massive quartzite which 



