LONG-ISLAND DIVISION. 
257 
arched clay beds near Brown’s point (vide Plate 4, fig. 7), are found layers of a fine, fat, 
reddish brown clay. It splits regularly into oblique-angled parallelepipeds, with a constant 
angle between its corresponding faces. The general form of these rhombic masses is like 
that of feldspar, except that none of the angles are right angles. 
Near Oysterpond village, the cliff, on the Sound side of the isthmus, was washed away at 
the base during the storm. The dark colored gritty clay, with its associated sand and gravel 
beds, surmounted by the drift stratum containing boulders, were exposed to view. 
Opposite Greenport, on the Sound side of the isthmus, the base of the cliff was washed 
away at the same time, so as to expose its strata. At the base, the cliffs are composed of 
horizontally stratified sand, gravel and pebble beds of variegated colors ; red, yellow, white 
and intermediate colors. The upper part of the cliff is of the greenish and bluish loamy 
deposit, containing great numbers of boulders and blocks, some of which are of great size. 
At Horton’s point, the blue gritty gravelly clay was seen like that on the shore near South- 
old, and described in many places along the north shore of Long island ; also between Hor¬ 
ton’s point and Duckpond point, two and a half or three miles west of the former point. 
At Roanoke point, and for two or three miles east, the cliffs were high, and the stratification 
was exposed to view by the inroads of the sea during the same storm (eleventh and twelfth 
of October, 1836). The strata of the Long-island division, towards the base of the cliff, of 
light colored and some variegated sands and bluish clay, are overlaid by the drift, deposit, and 
that by the quaternary sands and clays. Slides are here common. The superposition, and 
the effects of springs producing quicksands, slides and ravines, are illustrated on the woodcuts, 
figs. 1 and 2, on page 33 of this volume. 
Near Hudson’s point, three beds of clay may be seen: the upper greyish; the middle 
bluish, and containing gravel and pebbles ; and the lower brown, with a tinge of red. They 
form a thickness of sixty to one hundred feet. 
The gravel and pebble bed mentioned as occurring in the tertiary on Lloyd’s neck, and 
which has been seen in many places, was seen in crossing every deep ravine near the north 
shore of Long island, between Miller’s place and Smithtown; and in fact, in nearly all the 
ravines to Flushing on the west, and to Nepeague beach on the east, where the hills are one 
hundred feet or more in height. 
A range of clay beds extends from near Smithtown to Riverhead, a little south of the road. 
Gravel and loamy gravels form a belt parallel, a little north of the clay; and a belt of loose 
sands, still further to the north. Clay was seen near Corum, a little to the west of the village, 
near the brick-yard. It is blue, more or less variegated with red. The position of this clay 
is illustrated on Plate 4, fig. 11; but the figure has been incorrectly copied. The first and 
third layers are loam, the second gravel, the fourth clay. The laminse of the gravel bed are 
not parallel to those of the loam, and these latter are unconformably placed over the clay. 
The clay bed seems to have been bent downwards, and the loam deposited in the valley, as 
the bed is thicker in the deeper part of the valley. The gravel seems to have been washed 
over this, after some farther derangement of the strata producing a slight fault. The figure 
does not shew all these circumstances. 
Geol. 1st Dist. 
33 
