290 
GEOLOGY OF THE THIRD DISTRICT. 
level than at the north, appearing as though the drainage or excavation of at least a large part 
was the effect of a flow north, and not in the present direction. 
The county presents but a few of the rocks of the district, the lowest of which are those 
of the upper part of the Hamilton group, which project from Onondaga county. These are 
found only in the north part of the town of Truxton, extending east from Tinker’s falls. The 
Tully limestone being a continuous mass through that section of the district, it will be found in 
all places where the space between the Genesee slate and the Hamilton group is uncovered, 
but was not seen in the county. 
The Genesee slate is exposed to a considerable extent in the side-hills in the towns of Pre¬ 
ble and Truxton, and in parts of Homer; these hills extend through those towns, being the 
north prolongation of the southern overlying masses, some of which terminate in Cortland, 
and others in the east and west valleys of Onondaga county. The termination of some of 
the hills is quite abrupt, and when viewed from the broad level valleys north from which 
they rise, are highly picturesque. The Indian tradition of coal existing in this rock near 
Preble corners, before noticed, has no foundation in fact. 
The Portage and Ithaca groups form the greater part of the surface rocks of the county. 
They are but thin at the north, increasing in thickness going south. They cover the whole 
of the towns of Cortland and Solon, the greater part of Homer and Scott, and the terrace 
between Truxton and Solon. They extend south along on both sides of the Onondaga river, 
diminishing in breadth south, and also along the Otselic river in Willet and Cincinnatus. 
Numerous quarries are opened in these groups, for building stone and flagging. The color 
is more generally olive, than at Ithaca, where but a small part of the mass comparatively is 
of that color. 
On the east branch of the Onondaga, about a mile or more above Port Watson, and to the 
east of Homer, are the quarries of Miller and of Derby. To the south of the same villages, are 
those of Stephens, of Rose, and of Betts. This latter shows, in the ascending order, grey 
sandstone with no regular lines of division or layers ; above this also sandstone, thin, and 
somewhat regular in its divisions, capped with argillaceous layers, rather broken ; the whole 
above twenty feet in thickness, and opened along a line of four or five rods. The quarries are 
above a mile from Port Watson. 
Bellows quarry, from which nearly all the flagstones used in Homer are obtained, is on 
the hill-sides to the east, and between Cortland and Homer. The lower part of the quarry 
consists of flags from one to six inches in thickness ; not so smooth or straight as those of 
Sherburne, but waved like the slight movements which water produces upon a sandy bottom. 
The flags, etc. contain fucoids large and small, some of which anostomose, and all are smooth. 
Above these layers, there is a line of concretions about a foot or more in diameter, with 
shale. On the top of these are slaty, broken up and partly decomposed layers of shale and 
sandstone, forming the refuse of the quarry. Some of the lower layers of sandstone contain 
vegetable impressions, and show small accumulations of coal, owing to the alteration which 
the material of the plants have undergone. 
