carboniferous system. 
285 
The second member only of this system is known in New-York; and from the situation in 
which it occurs, little of interest or importance can be expected from it, except as showing the 
remains of an important formation, which once extended widely over the southern tier of 
counties, but from subsequent operations has been almost entirely removed, leaving only the 
isolated fields and blocks which indicate its former extent and importance. 
The Old Red sandstone in the Fourth District, is succeeded by a coarse siliceous con¬ 
glomerate, and a grey diagonally laminated sandstone, the former generally prevailing. The 
conglomerate consists of a mixture of coarse sand and white quartz pebbles, varying from the 
size of a pin’s head to the diameter of two inches. They are generally oblong, or a flattened 
egg shape. Some of these are of a rose tint when broken, but white upon the exposed sur¬ 
face. Pebbles of other kinds are very rare in the mass, though red and dark colored jasper 
are sometimes found. 
This rock in the Fourth District occurs in outliers of limited extent, capping the summits 
of the high hills toward the southern margin of the State. It is represented on the map by 
small dark spots, and its relative position is seen by an inspection of the sections crossing 
the counties (Plates 10, 11 and 12). From the absence of the red shales and sandstones 
forming the Old Red, this rock, on the west of the Genesee, rests directly upon the Chemung 
group. 
From its position, it has been much undermined; and sepaiating into huge blocks, by 
vertical joints, which are often many feet apart, the places have received the name of ruined 
cities , Rock city, &c. The sketch at the head of the chapter will give an idea of the cha¬ 
racter presented by this rock in its exposed edges. In many situations it can hardly be con¬ 
sidered as being in place, the wearing away of the rocks beneath having allowed the mass to 
fall down, so as to occupy the side of a hill instead of the summit. 
It is often much broken, and scattered fragments extend on all sides of the principal outliers 
to considerable distances. In many instances I have detected huge fragments of this rock 
nearly as far north as the northern limit of the southern range of counties, lying on the hill¬ 
sides, and sometimes in the valleys. At first I was disposed to consider these as transported 
from the south, knowing no rock in place of the kind so far north. Subsequent investigations, 
however, have convinced me that these fragments are the remains of the rock itself, which 
once extended continuously much farther north than its most northern outliers at the present 
time. 
In some instances, we find perhaps but a single mass; again we may find several, and in 
a few instances I have found a long range of fragments flanking the southwestern slopes of 
hills, and a similar arrangement upon an eastern slope, and again upon the summit of a broad 
flat table land surrounded by higher hills. These fragments have all the characters of the 
rock in place, and some of them occur in the immediate vicinity of such localities, and in one 
or two instances to the south of points where the rock is known in place. The occurrence, 
therefore, of single fragments, or of several in proximity, in the southern counties of the 
