536 
GEOLOGY OF THE FIRST DISTRICT. 
A granite quarry might be opened with advantage on the shore, about one mile south of 
Fort Montgomery, and east of Mrs. Pell’s house. 
Several quarries can be opened on Wagon’s islands, between Fort Montgomery and Cald¬ 
well’s landing. 
One or more quarries can be opened at the foot of the Dunderberg mountain, between 
Caldwell’s landing and Wagon’s islands. 
These quarries may all be opened directly on the shore, and blocks of large size may 
apparently be quarried with ease, and swung directly on board vessels by means of cranes. 
Should these stones prove as good as their external aspect would seem to indicate, it would 
be difficult to estimate their value, which would be very great. 
A valuable quarry may be opened on Stony point, a little west of the light-house. This 
part of Stony point next the United States’ land, belongs to Mr. Brewster. There are about 
ten acres of granite of good quality, and which may be worked to a mean depth of sixty 
feet to high-water mark. This place ought to be able to furnish one million cubic yards of 
granite, or 27,000,000 cubic feet. This rock is the proper granite, composed of quartz, fel¬ 
spar and mica. It is darker or as dark colored as the Quincy stone; is as durable, and as 
easily dressed. This quarry ought in the course of working to yield a nett profit of one million 
dollars, if the stone should prove as sound and easily quarried as its appearance would seem 
to indicate. The aggregate amount of workable granite in locations just described on the 
right bank of the Hudson in the Highlands, is estimated at 100,000,000 cubic yards, or 
2,700,000,000 cubic feet, a quantity that may be considered inexhaustible. 
Granite veins. These are very numerous, and may be seen in every quarry, and in every 
cliff and naked surface of the rock exposed to view. Some are very tortuous, others nearly 
straight and smooth on the sides, but most generally they are very irregular, and connected 
with intertruded and interlaminated irregular masses and beds of granite in the gneissoid rocks. 
The granite in the veins is of much finer grain and texture than that of the large masses and 
beds. Minerals are rarely found in them, except quartz, felspar and mica. Garnets, horn¬ 
blende, epidote, sulphuret of molybdenum, pyrites, etc. are occasionally seen in the veins. 
Numerous fine examples of veins, beds and irregular masses of granite may be seen at and 
near West-Point. 
2. SlENITE. 
This rock occurs abundantly in the Highlands. It is usually a coarse granitic aggregate, 
composed mostly of whitish or reddish felspar, and containing masses of hornblende, inter¬ 
mixed sometimes with magnetic iron ore or epidote. 
The following localities may be mentioned : 
