in the vicinity of Great Barrington, Mass. 263 
In some places in Beartown Mountain there are hornblendic 
layers; and at one ascent of the mountain made from the west 
side, about midway between the north and south extremities, I 
- found, near the top, a dark-gray, fine-grained layer, exceedingly 
tough, consisting largely of quartz and massive garne 
spur just east of the south end I observed in the gray gneiss a 
~ 
the Stockbridge limestone. Precisely the same kinds of gray, 
white, and quartzitic gneiss I found constituting the first ridge 
south of the road that leads up the valley to Washington from 
near Lenox Furnace. The Stockbridge’ limestone makes the 
base of the ridge and outcrops at its western foot; and the 
marble quarries of Lee are the same stratum two iniles to the 
southwest. 
Leaving now the region of the preceding section and Bear- 
town Mountain, we may go west to the low north-northwest and 
south-southeast ridge that extends from Three-mile Ridge north 
to the south end of Monument Mountain, and follow the ridge 
northward. 
First, at the notch where the road from Great Barrington 
passes through Three-mile Ridge, the gneiss is nearly horizontal, 
with a slight dip, where distinct, to the westward, as in Three- 
mile Ridge just to the south. 
A mile and a half to the north of the notch, a rocky bluff 
Monument Mountain the ridge is mostly under soil; and along 
the western slope all is earth-covered. Toward the base of the 
of a shallow synclinal, but a narrow one. 
Reaching the notch along which the Stockbridge road a 
the south end of Monument Mountain (near the east or right en 
- » 
*I speak, p. 262, of “ rising b: h and steep road to the top of this plateau. 
p. 408 g by a rough and § 
Near the point there reached, in the limestone area north - -segltiee to bs 
thodophyllite (rose-colored pyrosclerite), but containing also Logg eT tal = 
grains ; and, later, another smaller loose mass ooo qu 
n crystallized chlorite, along with large imperie 
beautiful rose-colored sphene. Since the first discovery I have been 1 
an excursion along its whole western side, no evidence of any W: : 
They may be of drift transportation. Until the minerals are oe pa pias ae 
I forbear to draw the conclusion—seemingly the most probable— : 
