A geological history of Manhattan or New York Island : together with a map of the island, and a suite of sections, tables and columns, for the study of geology : particularly adapted for the American student / by Issachar Cozzens Jr.

  • Cozzens, Issachar, 1780-1865.
Date:
1843
Catalogue details

Licence: Public Domain Mark

Credit: A geological history of Manhattan or New York Island : together with a map of the island, and a suite of sections, tables and columns, for the study of geology : particularly adapted for the American student / by Issachar Cozzens Jr. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    Avenue (as is shown by the blue on the map.) This rock begins, on the south side of, and under- lies Governor's Island, which is its most southern extent, passing through New York Island, and running through the greater part of Westchester County : it forms the rock, at the straits called Hell-gate, and even at that place (where it may be traced some 8 or 10 miles) underlying Long Island. The Gneiss of New York Island is a peculiar variety, and has more Mica than common, and which is also in larger plates than usual for this rock: some of this Gneiss, might with propriety, be called coarse Mica Slate. It is not a good building stone, on account of its splintering pro- pensities, which makes it dress uneven and rough, if it is struck with an intent to make a cross frac- ture, it is sure to split the wrong way. On the 10th Avenue near 60th Street, it is associated with Hornblende slate, and a granular Quartz rock, and at the Railroad Tunnel at Yorkvillc, with Hornblende. On the East River, above Bellevue, are precipitous Gneiss rocks from 20 to 30 feet high, forming bold bluffs, and overhanging the water ; at this place, it is sometimes, charged with Sulphuret of Iron in a state of decay, as may be