370 J. D. Dana—Geological Relations of the 
the mouth of Roaring Brook) about seven miles northeast of 
Oregon—a village on the borders of the two counties. 
fine-grained white to blue limestone and occurs with a well 
marked by the T-symbols. Below this, there are no out- 
crops of rock, and its limits southwestward are consequently 
undetermined. This valley—Peekskill Hollow—is so narrow ° 
for much of the way above Adams Corners that it is probable 
that the limestone is not continuous, but that the present spots 
are what is left after long denudation. There can no 
reasonable doubt that the large, open valley was once the course 
of a broad band of the limestone for the whole of the seven 
miles in Putnam County. 
The facts observed with respect to area 30 A and the asso- 
ciated mica schist and quartzyte are mentioned on page 214. 
Mather speaks of an outcrop of limestone, with “ hornblende 
rock adjoining it on the east,” at the Lower Dock of Peekskill. 
This spot is now graded over and the observation cannot be 
confirmed ; but it lies in the line of this area where it would 
reach the river. If it is correct, the rock which adjoins the 
limestone in this part is noryte, and no mica schist intervenes 
between this rock and the limestone, as it does 150 yards north. 
To the eastward, in Peekskill village, there is limestone in 
the mica schist on the Crom Pond road, according to Mather ; 
and north of the Academy grounds there appears to be an out- 
crop in the road; and this lies on the south margin of the valley 
in which this area occurs. The limit of the area eastward is not 
determinable; it may possibly connect with that of Peekskill 
Hollow, though this seems to be hardly probable. 
Areas 31, 32, 83, 84 and 35.—Number 81, in the southern 
part of Somers, east of Hallock’s Mills, trends nearly east and 
west; it is made up of two parts, a western and eastern, the 
strike in the former N. 58° E., and that in the latter east-and- 
west. 
Number 32, in North Somers, east of Somers Center, is 
another nearly east-and-west area, the strike averaging N. 71° 
umbers 88, 34 are small areas, too limited in extent of 
outcrop to determine their characters, beyond that of an approx- 
imately east-and-west trend. No. 35, or that of Lake Wack 
bue, has, according to Percival, the extent given it on the map. 
I have seen outcrops only between the lake and the pond west 
f it , 
Areas 36, 37 and 38.—The large North Salem belt, No. 36, 
first laid down by Percival, is six miles long, and has an east- 
and-west course. It has in some parts a band of gneiss 
