ALLUVIAL DIVISION. 
31 
clouded during high winds with the lighter particles of drifting sand, while the heavier are 
rolled along on the surface. Every obstacle which creates an eddy current in the wind, as a 
rock, fence, bush or tree, causes a deposit of sand, which often serves as a nucleus of a hillock. 
The sand-banks, when first formed, present almost as much variety of outline and form as 
snow-drifts after a snow storm. Examples were observed on the north shore of Long Island 
during the heavy winds of October, 1836, where heaps of drift sand, two or three feet deep, 
were formed in a few hours behind boulders and blocks of rock, which created eddy currents 
in the wind. Sand-banks several feet deep were observed in some of the ravines next the beach, 
that had been formed- between the time of the storm of the 12th, and the time observed on 
the 17th October. A small pond near Horton’s point, has been converted into a meadow by 
the drifting sand filling it up, within the remembrance of Mr. Horton of Southold. 
The sand-dunes along the shore are so prominent as to mark the line of coast in many places, 
when seen at the distance of several miles ; presenting a very broken, undulating or serrated 
outline of white hillocks, from ten to forty feet high. On almost all the beaches are hillocks 
of drift sand, and in many places the high bluffs on the north coast are capped with them. 
Jacob’s hill, northwest of Mattituck, was once much higher than Cooper’s hill east of it; but 
the sand has blown off, so that it is now much lower at the former place. Some arable land 
has been covered over, and red cedar trees have been buried by the drift sand. The grounds 
occupied by the dunes are exceedingly irregular in form; in some places covered with small 
round-backed hiUs, with deep, irregular or bowl-shaped valleys, formed by the wind scooping 
the sand out, where it is not confined by the roots of the scanty vegetation that gains a foot¬ 
hold in some places. The myrtle bush {Myrica cerifera), the red cedar {Juniperus virgi- 
nianus), the beach grass {Psamma arenaria), and a small creeping vine, are almost the only 
things that take root in these changing, arid sands. 
The south shore of Long Island, from Nepeague beach to Southampton, is skirted with a 
line of sand-hills, presenting a very irregular broken appearance in the distance. Nepeague 
beach is covered for a considerable breadth with loose drifting sands, forming small hillocks 
of almost every variety of shape. The south beach of Long Island is almost entirely a line 
of hillocks, and is composed of a chain of long narrow islands of sand, from one to five or six 
miles from the main island. 
The sand washed up by the surf, having dried on the beach, is borne inland by the wind, 
and piled up in heaps ; and in some parts of the world, in consequence of the predominance 
of certain strong winds in one direction, they make a regular progressive movement, burying 
farms, houses, cities, and even whole tracts of country. No effects of this kind were observed 
on Long Island, of sufi&cient moment to affect the general value of farms, except in a few 
individual instances. 
Should such causes ever threaten the destruction of property, their effects may be arrested 
by the cultivation of some plants which vegetate only in the most barren sands ; by this means, 
their roots will confine the sand, and prevent its drifting. This course is pursued in some 
parts of Europe with obvious advantage. 
