J. D. Dana—Taconie Locks and Stratigraphy. 405 
with quartzyte, the rock of the region, above. Only a few feet 
without rock intervenes between the schist and quartzyte. 
Section 42. In Washington, near Ashley Lake, quartzyte 
and mica schist in contact, with like dip. 
ARGS, 
SW Son 
SS 
WZ 
Se 
SS > 
SS Bren 
S NG 
42. Ashley Lake, 
Section 43. At the north foot of South Mountain, south of 
Pittsfield, near the road, where there has been quarrying. The 
westward dip indicates the synclinal structure of the mountain. 
Section 32 (page 402) represents well also a section at the 
southwest base of Sugar Loaf Mountain in New Ashford. 
Sections 44-48. These sections in Adams, North Adams 
and Williamstown bear on the question as to the synclinal 
structure of Greylock. Section 44 represents the limestone 
Washington, 
45. W. side of Graylock, at the 
Hopper, Williamstown, 
46. Same as 45, but S. of Entrance. 47, West of N, Adams. 
and schist at the east base of Greylock, in Adams, showing the 
westward direction of dip and its small angle, sustaining the 
observations of Prof. Emmons and Prof. EH. Hitchcock. 
Sections 45, 46 are from the western base of the Greylock 
Mountains, in Williamstown, at the entrance to the Hopper, 
48. Saddle Mountain Section, Emmons, 48.A Greylock Section atter Hitchcock. 
and also agree with Emmons. From these and other observa- 
tions, Emmons’s section, copied in section 48, was made. Farther 
west, in the southern part of Williamstown, the strike becomes 
