No. 200.J 
126 
Localities. 
The principal marshes of Long-Island are, Nepeague marsh; one be- 
tween Sagg-Ponds and Mecock bay, east part of Shinnecock bay; be- 
tween Moriches and Great West Bay; between Ocombamack neck and 
Fire-Place; Ocombamack neck and Patchogue; Patchogue and Nicho- 
las neck; and the very extensive one from Nicholas neck to Rockaway; 
and those about Jamaica bay and Coney Island. 
There are also many on the north shore of Long-Island, the principal 
of which are at Acabonnick, Oyster-ponds, Riverhead, Wading river, 
Smithtown harbor. Crab meadow, Lloyd's neck. Oyster Bay harbor, be- 
tween Peacock and Oak neck, Musquito cove, north part of Cow neck, 
Little neck bay. Flushing, Williamstown, Brooklyn, and Cowannus. 
The salt marshes of Staten Island, though not numerous, are exten- 
sive. The principal are the Greatkill meadows, Freshkill marshes, and 
those along the west coast of the island. 
The salt marshes of Suffolk county are estimated to cover an area of 
55 square miles; of Queens county, 40 square miles; Kings, 12 square 
miles, and Richmond 9 square miles; making an aggregate of 116 
square miles, or 74,246 acres, of marsh alluvion of the south coast of 
New- York, exclusive of the extensive marshes on the south coast of 
Westchester county, which would probably swell the aggregate to 125 
square miles, or 80,000 acres. 
As these alluvions are so extensive, the importance of rendering them 
most productive is sufficiently apparent. 
Encroachments of the Sea. 
Several examples of the encroachments of the sea on the land in Suf- 
folk county were mentioned in my first report. Others equally inte- 
resting and instructive, and as important in their bearing upon econo- 
mical and topographical geology, occur in Queens, Kings, and Rich- 
mond counties. Hog Island, as it has been called, or Middle Island, 
the name given by the coast surveyors, is gradually wearing away in 
many places by the action of the waves during storms and high tides; 
but the N. N. E. and N. W. parts, are exposed to the waves of 
Long Island Sound, and are wearing away more rapidly. The materi- 
als of which this Peninsula, as well as nearly the whole of Long Island, 
is composed, is a series of beds of sand, gravel, loam and clay. Boul- 
ders and erratic blocks occur in one of the beds in great numbers, and as 
the surf undermines the cliffs, they tumble down, and all the finer ma- 
