MOUNT GKEYLOCK. 177 



is ;i shallower trough analogous and parallel to' the minor one .shown on 

 Section P. 



Sections It 1 and It" pass through two of the minor synclines on the west 

 flank of the Greylock mass; R' through Stone hill and Deer hill, the syn- 

 clinal axis of which probably continues southward through East mountain 

 (Section L) and Potter mountain. At the north end (see Appendix A, Stone 

 hill) the north pitch is not directly observable, but is partially indicated by 

 an observation of Mr. Hobbs in one of the ravines of the Taconic range. 

 The relations between Stone and Deer hills are a repetition of those which 

 have been inferred between Clarksburg mountain and the Greylock mass, 

 the quartzite of Stone hill pitching under the limestone of Green river, and 

 that under the schists of Deer hill. 



Section B." passes through Sugarloaf mountain (see Appendix H), one 

 of the smaller lateral synclinal axes, which, farther north, appear in Bald 

 mountain ami Symond's peak (Sections G and I). In this part of the syn- 

 cline, which measures only about 6 miles in length, there are two well 

 marked troughs, one underlying Sugarloaf, and the other the high schist 

 ridge south of it. 



RESUME, STRUCTURAL. 



Mount Greylock, with its subordinate ridges, is a synclinorium consisting 

 in its broadest portion, of ten or eleven synclines alternating with as many 

 anticlines. While the number of these minor synclines is so considerable at 

 the surface, it is found, in carrying the sections downwards, that they resolve 

 themselves chiefly into two great synclines with several lateral and smaller 

 ones. The larger of these two forms the central ridge of the mass: the smaller 

 one, east of it, forms Ragged mountain and an inner line of foothills farther 

 south. The anticline between these coincides with the Bellowspipe; that 

 on the west of the central syncline is a little west of the north and south 

 part of the Hopper. The major central syncline is so compressed east of 

 Symonds peak (Mount Prospect) and Bald mountain, and its axial plain- is 

 so inclined to the east that the calcareous strata, which underlie the cen- 

 tral ridge, have on its west side a westerly dip (Sections (I and I). Far- 

 ther south this syncline opens out (Section K), and all the relations become 

 more normal. But between the villages of Cheshire and Lanesboro the 



3ION XXIII 12 



