114 
GEOLOGY OF THE FIRST DISTRICT. 
pyrites have decomposed. Another locality has been described near West-Point,* which is 
understood to be near Fort Putnam. I have not seen it there as native sulphur. 
Should the supply of sulphur from foreign countries cease from any cause, so as to raise 
the price of that article, the resources within the limits of our country could supply any de¬ 
mand. Beds and veins of pyrites abound in the State of New-York, from which sulphur 
may easily be obtained. Some of the localities of pyrites of the first district will be men¬ 
tioned in the proper place. Sulphur, to the amount of some tons, could be procured from the 
earth and tufa at the Sharon springs, but not sufficient to justify the expense, except in case 
of an emergency. Sulphur has been observed in fissures where alum occurs near Catskill, 
on the Helderberg mountain.t 
Carburetted hydrogen is known to issue permanently from but few points in the First Geo¬ 
logical District. At the salt well in the valley of Elk creek, three and a half miles from 
Delhi in Delaware county, bubbles of this gas rise through the salt water continually, and 
may be inflamed. Tn Dutchess count}?-, an inflammable gas, very pure, rises from the bottom 
of a small lake in the township of Northeast.^; At the mineral springs bored for McCulloch’s 
brewery, carburetted hydrogen is evolved.^ 
8. Sulphate op Iron. 
The sulphate of iron is formed by the oxidation of either the common or the magnetic py¬ 
rites, both of which are common in many parts of the First Geological District; and this salt 
is found efflorescing on those rocks in situations partially sheltered from the weather, that 
contain pyrites susceptible of decomposition.!! The localities of this salt are very numerous, 
but few of them promise to be of much importance. 
In Dutchess county, it w'as observed in small quantities efflorescing on the mica slate, about 
two miles southwest of Ameniaville, on the east side of the mountain, near an old excavation 
that had been made under the expectation of finding coal; also four miles south of Amenia¬ 
ville, at the south end of Barker’s mountain, on mica slate; and about two miles south of 
Poughkeepsie, on the shore of the Hudson, where an excavation and boring had been made 
in search of coal in the black slate of the Hudson river group of rocks. At all these localities, 
the bisulphuret of iron was disseminated through the rock. 
In Putnam county, many localities of sulphate of iron were observed. 
1. An old mine hole in hornblendic rock, a quarter of a mile east of Luddington’s corners 
in Kent, six miles north of Putnam court-house. Copperas effloresces, and causes this rock 
to crumble to sand. The excavation, which is small, is on the west side of the mill-pond. 
* Robinson’s Catalogue of American Minerals : Douglass and Webster, p. 145. 
t Robinson’s Catalogue of Minerals, p. 132. Webster’s Catalogue of Minerals, p. 6. Eaton’s Geological Survey of Albany 
county. 
t Ackekly. Geology of the Hudson. Cleaveland's Mineralogy, p. 483. 
Prof. L. C. Beck. N. Y. Geological Report, 1838, p. 41. 
II Some pyrites do not decompose, unless they be chemically or mechanically acted on by some artificial means. 
