196 GREEN MOUNTAINS IN MASSACHUSETTS. 



em face of Round rocks and the steep south side of Saddle Ball. The former 

 is a very striking object in the landscape both from the east and west. 

 (Compare Section Q with PI. xrn and Fig-. 74). An east to west system of 

 joints and fractures growing out of the pitch may have aided glacial and 

 other erosion at these points. 



The great west spurs which characterize the west side of the range 

 (PI. x.iii) are portions of the mass left by the erosion which chiseled out the 

 Hopper and the hollows farther south, while the pleasing variety of surface 

 features seen on the east side from Hoosac mountain (PI. xn) is the result 

 of the Berkshire schist forming a series of foothills between the upper and 

 the lower limestone. Some of these are also shown in PI. xv, the view 

 from Lenox mountain. East of the summit, however, these schists have been' 

 eroded almost down to the level of the Stockbridge limestone, thus enabling 

 one to look over from Hoosac mountain into the area of the Bellowspipe 

 limestone and southwards for. 2 miles to a point where the Berkshire schist 

 rises from under the Bellowspipe limestone and hedges it in ("The Canoe" 

 PI. xix), forming several considerable masses, the pinnacle and the southeast 

 spur of Bald mountain. These constitute the ridge between the northern 

 and the southern trough of the eastern syncline and shut in the view. (Com- 

 pare PI. xn and Section P.) 



A careful comparison of the topography and geology of the map, with 

 the transverse and longitudinal sections, and the general views (Pis. xn, 

 xm, xv, and Figs. 30, 75) will show more clearly than words can the general 

 structural relations of the Greylock mass to its surface features. 



