ALLUVIAL DIVISION. 
19 
The salt marshes of the island of New-York are the Stuyvesant meadows, extending from 
Corlaer’s hook to Twentieth-street, and about half a mile wide, now mostly covered with gra¬ 
vel, graded, laid out in streets, and partly built over; and the marshes near Harlem and 
Kingsbridge. The Collect was a quagmire seventy-five feet deep in the middle, and received 
the drainage of the higher grounds around. The water at its bottom was as salt as that of the 
Hudson, and from which its salt water is supposed to have filtered through the gravel. This 
pond and mud-hole had an outlet leading to the East river, along where Roosevelt-street is at 
present, and another communicating with the Hudson across the Lispenard meadows. This 
latter outlet crossed Broadway at the present corner of Broadway and Canal-street. Mr. 
Disbrow, in boring for water at the Halls of Justice in Centre-street, passed through forty 
feet of made earth, and thirty of black mud, in the old Collect, Blue clay and gravel lay 
below, and the latter rested on the rock, “ The Lispenard meadows extended from Broad¬ 
way to the Hudson, and from the vicinity of St. John’s church to Spring-street, including the 
range of Thompson, Laurens and Wooster-streets.” {Prof. Gales’ Report.) 
The meadows on the Hudson river, classed under the fluviatile alluvions, might also be 
classed as salt marshes as far up as Hudson, The salt water reaches as far as that city 
during spring tides, and when the river is low in the summer. The principal of these are 
the meadows south of Nyack; those at the mouth of the Croton river; near Haverstraw ; 
near Peekskill; between Caldwell’s landing and Fort Montgomery; and those of Consook 
island, and of Constitution island. 
The coarse marine peat of the salt marshes may also be made available for making car¬ 
bonate of soda, or a substance analogous to barilla or kelp, since it is saturated continually 
with salt water. If dug, dried and burned, the ashes would afford this material. 
Encroachments of the Sea. 
The coast of Long Island on the south side, from Montauk point to Nepeague beach, a 
distance of about ten miles, is constantly washing away by the action of the heavy surf 
against the base of the cliffs, protected only by narrow shingle beaches of a few yards or rods 
in width. The pebbles and boulders of these beaches serve as a partial protection to the 
cliffs during ordinary tides in calm weather; but even then, by the bouldering action of the 
surf as it tumbles upon the shore, they are continually grinding into sand and finer materials, 
which are swept far away by the tidal currents. During storms and high tides, the surf breaks 
directly against the base of the cliffs ; and as they are formed only of loose materials, as sand 
and clay with a substratum of boulders, pebbles, gravel and loam,* we can easily appreciate 
the destructive agency of the heavy waves rolling in unbroken from the broad Atlantic, The 
destruction of land, from this cause, is less than one would be led to suppose, but still it is 
considerable. The road from Nepeague beach to Montauk point, which was originally at 
Vide Section at Montauk point. 
