Page:Popular Science Monthly Volume 10.djvu/457

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441
THE LONG ISLAND COAST.

of the period we are considering. An artesian well is being bored on Barnum's Island, already mentioned, within two miles of the ocean. The island is but a knoll of tillable upland, surrounded by meadows and the waters of the bay.

The boring has reached a depth of 368 feet, or about 358 feet below

PSM V10 D457 Stratified beds and drift reach the ocean.png
Fig. 2.—Section from Hills at Centre of the Island, near Wheatly, to the Ocean, showing Stratified Beds overlying the Unmodified Drift.
Vertical section, one inch to five hundred feet. Horizontal section, one inch to three miles.

tide-level, and is still in progress. We present below a statement of the series of deposits penetrated. Our table is prepared from the record of Theodore F. Carman, Esq., of Hempstead, Long Island, engineer of the work, and from eighty specimens of the layers passed through, furnished by that gentleman:

1.— 70 feet. Yellowish gravel and sand.
2.— 56 " Clay. Upper portions with decayed vegetation, wood, and lignite.
3.— 3 " Coarse gravel and sand.
4.— 46 " Sands, with clayey crusts and pyrites.
5.— 25 " Sands, with some lignite.
6.— 54 " Clayey sands.
7.— 94 " Fine sand, sandy clay, with much lignite in the more clayey portions.
8.— 4 " Fine sand.
9.— 1 " Very firm bed of lignite, in fine decayed vegetable matter and clay.
10.— 10 " Clay, with lignite.
11.— 3 " Clay, very fine, without lignite.
12.— 2 " Sandy clay.
Total, 368

Our grouping of the deposits may suggest transitions more sharp than the specimens warrant. About 70 feet of the surface is of yellow or orange colored sand and gravel. Then occurs a bed of clay 56 feet thick, on the surface of which was found decayed vegetable matter having a strong odor of carbolic acid. Wood and lignite occurred in this bed. Beneath was found a layer of coarse gravel and sand.

None of the layers penetrated are of the unmodified drift. No shells have been found, nor other remains of animal life, excepting a very small fragment of a crinoidal stem which occurred in a thick bed of coarse silicious sand 160 feet below the surface. This specimen, which is much water-worn, Prof. Dana suggests may be of cretaceous species, but it affords little or no evidence that the deposit in which it was found is of Cretaceous age. The Silurian and Devonian fossils, which occur frequently in the drift of Long Island, cannot be considered as proof that the deposits are Silurian or Devonian.