88 
[Assembly 
There is one circumstance connected with these boulders which 
I will mention, on account of the bearing it has upon some ques- 
tions in the scientific part of geology. I will state only general 
facts, without entering, at this time, into the minute details, or the 
conclusions to be drawn from them. The boulders and blocks 
vary in size from a pebble to masses weighing several hundred 
tons,* and are mostly found on the range of hills running through 
the island, and between them and the north shore. The boulders 
and blocks are contained in a stratum which is inter-stratified with 
deposites of sand, clay and gravel, and is often exposed along the 
coast. Some of the blocks when first disinterred, exhibit scratches 
upon one or more of their sides. Rocks like those occurring on 
Long Island are found in Rhode Island, Connecticut, and along the 
Hudson river, and they are so similar in their mineralogical cha- 
racters and associations, as to lead to the conclusion that they were 
originally derived from those places. Again, as we progress west- 
ward from Montauk point to Brooklyn along the north shore, there 
is a regular succession of the groups of boulders, pebbles and gra- 
vel, corresponding to the successive changes in the rocks on the 
north side of the Sound. For example, the boulders on the east 
end of Long Island, are like the granite, gneiss, mica slate, green- 
stone and sicnite of Rhode Island and the east part of Connecti- 
cut; further westward, opposite New-London and the mouth of 
Connecticut river, are boulders like the New-London and Connec- 
ticut river granites, gneiss and hornblende rock; opposite New- 
Haven, are found the red sandstone and conglomerate, fissile and 
micaceous red sandstone, trap conglomerate, compact trap, amyg- 
daloid and verd antique; opposite Black-Rock are the granites, 
gnftiss, hornblende, quartz and white limestone, like those in Fair- 
field county; and from Huntington to Brooklyn, the trap (compact, 
crystalline, &c.) red sandstone, gneiss, granite, hornblende rock, 
serpentine and crystalline limestone, are found identical in appear- 
ance with those of the country between New- Jersey and Connec- 
ticut. The fact of the perfect correspondence of the mineral cha- 
racters, and of the associated minerals of these pebbles, boulders 
and blocks, with those of known beds on the main land, has alrea- 
dy been alluded to; but another fact of as great importance, is, 
that these blocks, boulders, &c. are in a southerly direction from 
those beds, and this direction is generally different from the line 
* A single one of these blocks at Oyster Pond point, has been split up, and a stone wall 
of four feet high and eighty rods in length has been made from that alone. 
