PRIMARY ROCKS. 
547 
Gneiss with beds of granite, frequently streaked with hornblende or with grains of magnetic 
oxide of iron, was seen in crossing the mountains farther west, to M‘Farlane’s iron-works in 
the valley of the Ramapo. 
Gneiss is the prevailing rock in this valley south to Sloteburgh, and thence southeast to 
where the Ramapo leaves the Highlands. In many places it is hornblendic, and passes into 
hornblende rock. Beds and veins of granite are not rare. , A fine granite for building occurs 
half a mile west of the Ramapo works, up the valley, and another about the same distance 
down the creek. These must be near the New-York and Erie railroad, and may perhaps be 
made available at some time, as the transport would be easy. The dip of the rocks is gene¬ 
rally at a high angle to the southeast or east-southeast. 
A bed of granite was observed on the hills about one-half to three-quarters of a mile from 
Capt. Faurot’s, four or five miles southwest of West-Point. 
Gneiss rocks are frequently seen in place along the road from Capt. Faurot’s to West-Point, 
and along almost the whole of the shore. They generally dip at a high angle to the east- 
southeast, and contain many beds of granite. Scarce a single quarry can be examined, or 
any considerable surface of the naked rock, without finding numerous granite veins. Many 
of them are very tortuous. Quartz veins are also not uncommon. Wherever cliffs are ex¬ 
posed on the shore, and particularly between Mearn’s landing and Buttermilk falls, and also 
between the latter place and Mrs. Kinsley’s, and near Block-house point, i\\e joints of these 
rocks are beautifully exposed to view. The rocks are divided into large blocks by these 
joints, of from a few tons to many hundreds and thousands of tons weight. The direction of 
the principal joints is about N. 60° to 70° W. They may be seen almost every where in 
the Highlands where cliffs are exposed. Along the shore, the cliffs frequently present a ser¬ 
rated outline to the water line, in consequence of the lateral heaves or faults along these joints, 
presenting mural escarpments on the southern and eastern sides. 
The rocks from West-Point to the Forest of Dean iron mines are gneiss, frequently horn¬ 
blendic, with beds of granite, hornblende, augite and limestone. Granite beds are numerous 
and extensive on the crests of the hills and mountains west, northwest and north of Kronkite’s 
and of Round pond. 
A bed of limestone about two and a half miles west of West-Point, has not been men¬ 
tioned. It is the grey siliceous limestone, apparently like the Calciferous rock of the Cham¬ 
plain division, slightly modified. This locality I have not seen, and the rock possibly may 
not be in place. I have only seen specimens, and been told that it was quarried and burnt 
into lime. The remains of two or three limekilns are within a short distance, near the road¬ 
side. 
On the road from the Forest of Dean mine to Fort Montgomery, a ridge of felspathic rock 
was seen, which from its aspect might be called granite. It would make a good building 
stone. It forms a high peak and ridge, about two miles west of Fort Montgomery, and it 
seems also to form the west side of Bear mountain to the south, and to extend also to the 
northeast to the top of Bare hill or mountain. 
69* 
