MOUNT GREYLOCK. 169 



locality .*i"_\ a little south of east from South Williamstown village, the struc- 

 ture of the schist is finely exposed (see Fig. 58), the coarse stratification 

 foliation (plications) dipping about 45° oast with a southerly pitch, associ- 

 ated with a, cleavage foliation dipping 35 east. Following this ravine 

 southerly, its sides gradually approach each other until the two rocks are 

 finally found in superposition with a westerly dip. 



'The chief points of interest in the remaining sections will he only 

 briefly referred to. 



TRANSVERSE SECTIONS A-F, J-O. 



Section A, PI. xviii, crosses the northernmost portion of the range at North 

 Adams, and shows a compressed syncline turned over westward. 1 The actual contact 

 may be seen about a thousand feet west of the North Adams railroad depot, the 

 limestone overlying the schist, both rocks striking north 22° east, and dipping 45° 

 southeast. I failed with careful search to find any quartzite outcrops in this part of 

 Greylock, although there are numerous bowlders of it which have probably been 

 brought from Clarksburg mountain or beyond. 2 There is room, between the lowest 

 outcrop of quartzite on Clarksburg mountain and the western side of the steep portion 

 of the Greylock mass traversed by this section, for a bed of limestone 1,400 feet thick 

 dipping at an angle of 50°, which is the dip of the schist at locality 916 (see map); 

 and none of the measurements of the thickness of the lower limestone obtainable on 

 Greylock indicate a greater thickness than that. 



Section B, PI. xvm, about a mile and a half south of North Adams. The limestone 

 of the lloosac valley and the schist of Mount Greylock appear here in their normal 

 relations. The syncline which farther south const i A 



tutes the central portion of Ragged mountain appears ; 

 and there is a second syncline west of it, identical with 

 the one on Section A, but open, and also with that on 

 the east side of the Notch. In the western portion of 

 the section two synclines and an anticline have been 

 conjectured from observations farther south. It will 



be observed that this section crosses the Greylock Fig. 65.— Cross-sections A, B. 



mass below the horizon of the upper limestone and calcareous schist. 



Section V, PI. xviii, about 2 mi es south of North Adams. The calcareous bench 



1 See J. D. Dana, Taconic Rocks and Stratigraphy, Sec. 17, p. 105. Also. On the Quartzite, Lime- 

 stone, etc., of Great Barrington, p. L'73. 



1 J. D. Dana, On the Taconic Rocks and Stratigraphy, p. t06: "A prolongation of it [the Clarks- 

 burg mountain quartzite] appears to exteud south of Braytonville into the north end of the Greylock 

 mass, along the ascending road (but chiefly on its eastern side) for a mile." 



