Page:Popular Science Monthly Volume 10.djvu/453

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deep. These dead and submerged meadows are but little decayed, and are usually continuous with those now growing upon the shores.

On the flat shores of the south side of the island the encroachment of meadow upon the uplands is attended with interesting results. It forms first in depressions where the tides overflow. In this way knolls of upland, cultivated or perhaps covered with trees, become islands, which are in turn overflowed and covered by meadow, but some of the more elevated ones remain almost at the verge of the ocean. Barnum's, formerly Hog Island, in East Rockaway Bay, now being converted into an asylum for the paupers of Queen's County, is one of these.

It is well known that the beach[1] on which the ocean breaks is gradually thrown inland upon the meadows. By this means old meadows are sometimes laid bare. It is stated, in Furman's "Antiquities of Long Island," that when Jones's Inlet was opened through the beach during a storm, it was found that the "bottom, laid bare, was solid meadow, in which were tracks of cattle, or of cloven-footed beasts."

The old meadow-bottoms, and sometimes masses of the tangled roots of upland vegetation, are torn up by waves during storms and thrown upon the beach. We have seen this turfy matter lying like windrows along the surf. Mr. Pelletreau informs us that just opposite the east end of Shinecock Bay "there was washed out by waves a large quantity of what is called meadow-bottom, partially decomposed vegetable matter, remains of fresh-water plants. . . . A few years since a violent storm washed away the sea-beach near Southampton, exposing at low tide, nearly at the brink of the ocean, a row of fence-posts that were put down by the first settlers." From these and other facts this careful observer concludes that the ocean, in that vicinity, has encroached upon the land about half a mile in two hundred years.

At Montauk Point, north of the lighthouse, is a low, swampy place, over which the tides sometimes rise. We are informed by Mr. J. F. Gould, who was for many years keeper of the lighthouse, that stumps are laid bare in front of this swamp, at the sea-margin, when the tide is extremely low. A similar phenomenon occurs at the extreme westerly end of the island. A few rods south of Fort Hamilton, at the entrance of New York Harbor, are the well-known Dyker Meadows (Fig. 1). They occupy the site of a swamp which is filled with the remains of upland and fresh-water vegetation.

The swamp was originally about a mile long, and was in one of the valley-shaped depressions common on the surface of the Long Island drift. It lost its character as a swamp by encroachment of the tides upon it, and was finally converted into a salt-marsh. This

  1. This breakwater of sand extends from Coney Island to the bills of Montauk, a distance of nearly one hundred miles.