Vermont telegraph. [volume] (Brandon [Vt.]) 1828-1843, 1839-05-15
sienitic Granite Of Staten Island

Scientific Granite OF Staten IsIands
This rock is not what geologists and
mlneraIogists call granite, but ii belongs
to the granite family. Those rocks
which receive the denomination of gran
lite, have at least three constituents, some
what confusedIy adhering together; these
are quartz, feldspar, and meid. The par
ticular rock in question has no meid and
very little leIdspar, but in their place con-
tains hornblende, compound mineral not
subject to decomposition in the open air,
which some kinds Of feldspar are liable
to and as the o:her constituent, quartz, is
a simple substance, not subject to decom-
position, conceive this rock to be indie
structib!e in the open air. 1t belongs to
the same class of rock with that of Sy-
enc, in Egypt, of which the ancients con-
structed obelisks and other lasting monu-
ments; and hence i. has received the
name OF Sienite, being in fact a Sienitic
granite Of very pare quality. - -a
Some rocks of this class contain acct
dental minerals, such as pyrites or sui
phuret OF iron. a mineral subject to spon-
taneouS decomposition, a process which
not on! y stains and discolors the conligu-
Gus parts of the walls of edfces, after
they are constructed, as may be seen in
various public buildings in this city, but
Eventually affects in an injurious manner
the cohesion. have not observed any
specimens OF pyrltes or other injurious
minerals in this rock. .....
The question whether this rock is f.
ted for the construction of public and pri-
vate edihces in the city of New Y ork, be-
ing considered by myself OF great impor.
lance in public point of view, have,
after examining specimens of it in this
city, visited the locality, near Port Rich
mond, Staten Island, to satisfy myself as
well as 10 the extent of tina. part of the
field easily accessible for quarrying, as to
the other important consideration, wheth-
er it is to be fairly considered as uniform.
y of proper quality for city construc-
tons. .. ...- 49,. 80 $780,.
The field in which the quarry is stu
ated, IS near mile to the point Of embark
alton, by a gentle slope. and forms part
OF very extensive bed running from
N. N. E. to SIS. W., but sinking in
: both directions under the low and wet ad
jocent lands. Here, however, it crops
Out on a broad hill. with working sur.
face of 1900 by 1900 feet, and 43 fee,
above the water level. SO that the quarry
is capable Of yielding about $4,000 0C
f OF tons, without having resource TO ar;if-
cial drainage. The rock is so uniform
IN lis quality, and so free from injurious
accidental minerals, that the quarry men
remark, that they never worked in rock
that yields to the wedge more regularly
or that splits with greater facility.
The blocks which | saw spit were OF
the greatest beauty, no portion of them
beng dscolored, even of those taken
from the surface; 50 that the inference
may be justly drawn, that the interior
paris OF the quarry wiz at least continue
as pure and beautiful as those which have
been already exposed
La various parts Of the hill, immense
masses present themselves without anv
seams. and of such apparent solidity as to
warrant the belief that architectural, COL
umns OF the largest dimensions may be
formed at the quarry. IT,. f.,
:. Satisfied that this Scientific granite of
| Staten Island is, for the reasons [ have
stated, indestruclible and incompressible !;
Tree from injurious accidental minerals !:
not subject to discoloration; of remarka.
Die facility for working; abundant in
quantity; and OF singular economical
transportation TO the city,-I do not hest.
ate to recommend it confidently as build
ing material, we'll fitted by its excellence
and beauty for the construction of public
and private edi6ces.
G. w. FEATHERsroNHAroH
NEw-YoRK, Feb. IA, 1899.