LOCALITIES OF SUPERPOSITION. 
197 
co. 
No. 1. Primary rock or system. 
2. Oalciferous sandrock, or group, } 
3. Birdseye limestone, r 
4. Trenton limestone, > Champlain, division, in part. 
5. Utica slate, L 
6. Hudson river group, lower part, j 
l [ Ontario division, i. p.„. 
i?: \ ,Wd " be " in t “- * F “ ta,r ” ,,ey ' 
From the absence of the upper part of the Hudson river group at the middle and east end 
of the Mohawk valley, the following wood-cut is given, which represents a section, passing 
west from Black river, terminating with the sandstone shale of Pulaski, being the upper part 
of the Hudson river group and Champlain division. 
ci. 
No. 1. Primary rock. 
2. Black river limestone. 
3. Trenton limestone. 
No. 4. Utica slate. 
5. Frankfort slate, and 
C. Sandstone shale of Pulaski, 
Hudson river group. 
The continuation of the section from Black river in a southwest direction, carries you over 
the surface of the Grey sandstone, which is well exhibited at the falls on the north bank of 
Salina river, and more finely at the great falls on the main river, where it is about one hun¬ 
dred and twenty feet in thickness. From the grey, the next rock in succession is the Medina 
or Red sandstone, which covers the greater portion on the south side of the west part of 
Oswego county. Then follows the Clinton group, which terminates the Ontario division, the 
Oneida conglomerate not having been seen in place in that county. 
