462 
GEOLOGY OF THE FIRST DISTRICT. 
and about half or three-quarters of a mile east of Horton’s pond. The rock is of a blackish 
green, fine grained, and sometimes coarsely crystalline. It is yellow on the weathered sur¬ 
faces, and is associated with steatite. Ten to eleven acres seem to be underlaid by this rock, 
which might be quarried for an ornamental marble. It is about eight miles from water 
transport. 
Another mass of the serpentine rock was seen about a mile south of the one last described. 
The serpentine forms knobs and hillocks at small intervals for half a mile in length. 
Another locality, one that has already attracted much notice, is Brown’s quarry, near Pine 
pond in Putnam county, four or five miles from Putnam court-house, and one and a quarter 
miles north-northwest of the county poor-house. It is dark colored, dark green to black, 
and from compact to a coarse crystalline, like coarse grained hornblende rock. It is granu- 
larly foliated like common white marble, polishes well, and is perfectly black when polished. 
It may be obtained in large blocks for sawing into slabs. Large blocks lie on the surface in 
Brown’s lot, and the rock is seen in place all around the hill. In the mine lot adjacent, good 
blocks may probably be obtained by quarrying. Twenty-five to thirty acres of ground are 
underlaid by this rock on the hill-side, wmst of the brook, which is the outlet of Pine pond. 
It is easily accessible, and about one hundred feet above the water level of the adjacent valley. 
Blocks of many tons weight can be easily procured; in fact many of this size are now lying 
on the surface, and require no blasting or splitting before they are put in the sawmill. Mag¬ 
netic oxide of iron, or chromate of iron, is disseminated through the serpentine in some 
parts of the serpentine bed ; and this variety of the rock will not be suitable to work, as it 
can neither be sawed nor polished easily. The quarry seems to be sufficient to supply the 
market, not only of our own country, but the world, with this kind of ornamental marble for a 
long time. It is really a beautiful material when polished, and it is hoped that it will be 
extensively used. I have seen no other locality where such a material can be obtained in so 
large blocks, sound and free from seams and cracks. A marble of this kind was used in 
ancient times in some of the old Spanish palaces, but it is exceedingly rare in Europe. 
Another locality of it may be seen on the peninsula east of New-Rochelle. It has been 
quarried to a small extent for marble ; but it is understood that good blocks, free from cracks, 
could not be procured. The serpentine at this locality shows almost every shade of color 
and texture, from black to light yellowish grey, and from compact and crystalline to earthy. 
It is bounded by hornblendic rocks on the west, and by limestone more or less mixed with 
serpentine and with siliceous matter on the east. Among the minerals noticed here, may be 
mentioned verd antique ; precious serpentine of a red, green and yellow color ; common serpen¬ 
tine, green, yellow, grey, black, compact, granular and earthy; jasper, chalcedony, agate, 
drusy quartz, marmolite, hydrate of magnesia; carbonate of magnesia, compact and crystal¬ 
line ; tremolite, magnetic oxide of iron, and chromate of iron ? 
The locality where the quarrying operations were carried on, was at high-water mark, and 
they dug perhaps too near the level of low water. Good blocks of this rock could scarcely 
be expected free from cracks, where they had been exposed to the beating surf and the winter’s 
