358 
GEOLOGY OF THE FIRST DISTRICT. 
neer may use without fear, of hazai’ding his reputation ; and his employer may feel certain 
that the structures built of. it; will not crumble down by the ordinary action of the weather in 
a few years, like some of our public works and private dwellings. 
It is surprising to see how little attention is paid to the selection of materials for construc¬ 
tion. Judging from what has come under my observation, the general impression must be, 
that any solid stone may, with equal propriety, he put into the walls of buildings. It is not 
so ; and in our public works and expensive buildings, it is of great importance to select ma¬ 
terials that will stand time unchanged. Some granites, limestones, sandstones, marbles and 
other rocks will stand the vicissitudes of the seasons for ages without any perceptible change ; 
others nearly similar in appearance, and belonging to the same kinds of rocks, will crumble 
to sand or powder in a few years. An experienced eye is necessary to judge whether parti¬ 
cular kinds of rock ought to be employed for structures that are intended to be permanent. 
Metalliferous veins have been found in several localities in the Shawangunk grits. There 
are traditions that lead ore has been cut out of the Shawangunk mountain in many places by 
the Indians and hunters of former days with their hatchets, and melted to make their bullets. 
Traditions of this kind are said to have led to the discovery of the lead ores at Ellenville, 
Redbridge and Wurtsboro’. Lead ore has been discovered at many other points on the western 
side of the Shawangunk mountains, and in so many places, that it is thought probable a me¬ 
talliferous vein may be almost coextensive in length with this range of mountains in Ulster, 
Sullivan and Orange counties. 
The Ellenville mine is within one half mile of that village, at the base of the Shawangunk 
mountain. The vein is one of the transverse breaks of the strata, and ranges south sixty 
degrees east nearly vertical. The materials filling the vein are nearly the same as the grit 
rock that it traverses, more or less loaded with pyrites and crystallized quartz, and in some 
places with blende and galena. The vein is from two to three feet wide, and a copious spring 
flows from near its junction with the marsh below. The mine was first opened about twenty- 
three years ago, and some lead and zinc ores were obtained, that were reputed to be rich in 
silver. The lead ore was said to have been more abundant in the marsh than where the 
“ mine ” was opened, and it is supposed the Indians and hunters obtained their supplies from 
the marsh. The “ mine ” has been worked again within a few years by the North American 
Coal and Mining Company. In has been said that the adit level penetrated six hundred feet 
into the mountain, but no lead ore of importance seems to have been obtained. I should sup¬ 
pose, from the mass of rubbish, that the level cannot have been carried so far; and again, 
they would undoubtedly have perforated the grit rock, and entered the subjacent slate rocks, 
in less than that distance. 
It is a fact well ascertained in mining, that metalliferous veins change in productiveness, 
and sometimes in the kind of ore, as they pass from one kind of rock to another. The grit 
rock of the Shawangunk mountain is overlaid by limestone,* and underlaid by the slate rocks 
• The limestone does not often cover the grit rock on the sides of this part of the mountains, but ranges along the valley, 
superposed in geological position. 
