168 
GEOLOGY OF THE FIRST DISTRICT. 
color, and gives a bright red streak when scratched. It is called by the inhabitants red chalky 
in consequence of its being used for a similar purpose. It frequently embraces the remains 
or impressions of plants.* It seems to have been iron sand on the ancient beaches, like that 
so often seen on the beach at the present time, but since aggregated into solid masses, enclos¬ 
ing organic substances, and changed to a peroxide of iron. Some of the specimens, however, 
have a striking resemblance to the clay ironstone of the coal formation, only changed to a 
peroxide of iron. The boulders in the Shinnecock hills are not confined to the elevated lands, 
as they are in most parts of the island, but are found at low levels as well as high. On the 
north side of Shawango neck, and at Oyster ponds, and thence to Rocco point, and near 
Horton’s point, they are also at a low level; but generally, the drift bed is elevated above 
the sea level, and the boulders on the beach and at a low level are the result of the degrada¬ 
tion of the land by the sea, and the crumbling down of the cliffs. 
In the Shinnecock hills, the boulders in some places seem to lie in groups ; but this cha¬ 
racter is not strongly marked there, as it is in many parts of the country. On the road two 
miles south of Sag-Harbor, the blocks and boulders are so numerous, and in such clusters, 
as to almost induce one to suppose the rock in place just below the surface. Most of these 
rocks bear a strong resemblance to the gneiss of Haddam in Connecticut. 
In Southold, the surface is generally a loamy gravel, or light loam. Boulders abound about 
Horton’s point, and thence to Rocco p int; also northeast of Oyster Ponds harbor, on the 
hills. A section of the boulder stratum is represented on PI. 27, fig. 3, about one or one and 
a half miles east of Horton’s point. A topographical sketch is also given of the place where 
the section was made across the beach. Boulders are numerous on the points at the extre¬ 
mities of the beach, and along the shore east and west. The layers of clay were much con¬ 
torted in many places, but the section gives the order of superposition. The clay contains in 
some places large masses of sand (several gallons), which, from their form, seem to have 
resulted from the disintegration of boulders while imbedded in the clay. The upper clay bed 
contains many pebbles, like that used in brick-making at Sag-Harbor, and many other places 
on the eastern part of the island. The boulders on the hills and shore consisted mostly of red 
granite and gneiss, like those of Stonington, Lyme, New-London and Waterford in Connec¬ 
ticut. Hornblende slate, green sienitic hornblende rock and greenstone, like those of Stoning¬ 
ton and Groton, were observed. 
Plate 4, figs 1, 3, 7, 9, shows the position of the drift. Fig. 3 is a section at a rocky point 
about half a mile west of Brown’s point. The strata of sand and clay beneath are undis¬ 
turbed ; and we can scarcely credit that such enormous boulders and blocks, as may be seen 
in the boulder stratum, should have been transported by water currents alone, without wash¬ 
ing away these deposits of sand.f No blocks or boulders are seen except in that stratum. 
• Specimens may be seen in the collection in the State Museum, among the specimens of drift from Long island, 
t Two or three days before my visit to this part of the coast of Long island, there had been a tremendous northeast storm, that 
caused a great destruction of property, and made great inroads upon the coast, exposing beautiful coast sections, fresh, and that 
showed the order of superposition of the various strata perfectly. 
