48 J. D. Dana on the Quartzite, Limestone, etc., 
the limestone does not reappear; but instead, there is sufficient 
evidence that the overlying schist or slate is the upper rock 
under the alluvium of the river. The large masses of rock in 
sight are mostly boulders ; yet some appear to be true outcrops, 
and if so indicate much variation a aoe ith none at a high 
angle. In the slopes of Tom Ball, along iis section, the slate 
of the lower part is nearly horizontal, or even westerly 15°, 
and some of it is calcareous; but forty yards above it changes 
to 40° to the eastward, wit ith the strike N. 5° E.; and higher 
up to 50°-70°, and even 80° at the summit. The west slope 
of the mountain in this part is very precipitous.* 
W A? H 
Section from Monument mountain westward, south of f 
4, 
V3 
Section ae Glendale westward. 
- 9. The section in fig. 4 was taken just north of the line of 
the old furnace, fon the map, or of the cross road f’. The first 
elevation west of the ecg is the ridge N, which is nearly 
a continuation of W ; but e W consists of quartzite, about 
N the quartzite is scar ere there are only the underlying 
beds of mica slate and limestone, a bluff of mica slate forming 
its summit—not over 150 feet above the river. The mica slate 
dips to the westward 25°. West of this ridge the section is 
essentially i same as No. 3, no limestone outeropping in its 
e slate being probably the upper rock underneath 
the levies 
3. a. Half to two-thirds of a mile farther north in the Housa- 
tonic valley, near 6’ (map), the schist on the east (right) of the 
*In n figures 3, 4, 5, W shows the positio n of Williams river, and ee 
Housatonic river; and the height on the west (left) is Tom Ball ridge. The letter 
same 
scale is to the vertical about as one to four. 
