No. 200. i 
275 
of alteration by exposure to the air, this rock will be an important ma* 
terial for Ike masonry of the Black river canal, which will pass not far 
from it. 
The gneiss, the calciferous, and the birdseye, being wholly confined 
to the town of Remsen and the Black river, leaves an extensive area for 
the Trenton limestone, and the black shale and the shales and sandstone 
of the lower part of Salmon river. 
Owing to the depth of alluvial, and the flatness of the country be- 
tween Utica and Rome, the boundary between these two last groups 
was not fully ascertained. In all probability it follows near the line of 
the canal from Utica, curving east of Rome towards Delta, thence pur* 
suing a north course to Lewis county. East and north of this line, is 
occupied entirely by the black shale and Trenton limestone; this latter 
rock every where separated from the green and the black shale. 
Within the area to which we have circumscribed the black shale and 
the Trenton limestone, we find the latter rock, which forms but a small 
portion of the surface, at a lower level than the black shale, with a few 
exceptions, arising from uplifts which extended into Oneida, altering the 
relative bed of the two rocks, as to collateral masses. 
The limestone is found along the course of Beaver Meadow creek to 
its mouth; in Steuben creek, and some of its tributaries; in the bed of 
the Mohawk, below Lansing's kill. It forms the two great falls of 
Lansing's kill; extending from the upper one, to near Boonville village, 
near Holland patent and Stitsville; also, along the course of Cincinnati 
creek, and of West Canada creek, forming Trenton falls, from whence 
it derives its name; and, finally, from Cincinnati creek it covers the 
whole of the narrow space comprised between the road to the village 
of Boonville and Black river. 
South of the Mohawk, the Trenton limestone, both in Herkimer and 
Montgomery counties, rarely exceeds a thickness of ten feet, nor much 
beyond that thickness in any part of the latter county. In Herkimer, 
between Fairfield and Middleville, (where it was quarried with the Birds- 
eye, for the building of the college and academy of the former village,) 
as well, also, at Stony brook, below Middleville, the limestone attains 
the thickness of more than thirty feet. At Trenton falls, the thickness 
is upwards of 100 feet, and at the falls on Lansing's kill, the common 
estimate of 76 for the one, and 50 for the other, the inclination of the 
bed of the kill and rock being the same, gives a thickness of 125 feet. 
These facts show, that this rock increases in thickness in the direction 
