TRENTON LIMESTONE. 49 



deposits at these latter localities, during which time the rock of the quarry to the southeast of 

 Amsterdam, of that at Tripes. hill, and at Sage & Reed's quarry on the south side of the 

 river, and the upper layers of the lower cliff on Black river, were formed, uniting the two 

 by intermediate characters. From the intermediate mass between the birdseye and the 

 Trenton limestone being invariably associated geographically with the birdseye along the 

 whole course of Black river through Lewis county, etc., it was described with that rock ; 

 exhibiting more of the mineral character of the latter rock, the fossils being those of the 

 Trenton limestone. 



The Trenton limestone is confined entirely to the counties of Montgomery, Herkimer, 

 Oneida and Lewis. Along the Mohawk, it is a rock of uplift ; and with the exception of the 

 Noses, it is not found further south of the river than about a mile. The last place where it 

 appears in the Mohawk valley, is on the south side of the river, about three miles west of Little- 

 Falls. The limestone is not found to the west of Lansing's kill ; it makes its appearance at 

 the mouth of Wells' brook, and continues up the Mohawk to the kill, and thence to Boonville, 

 the kill being its extreme western boundary in Oneida county. It forms the second terrace 

 of the west side of Black river, ranging parallel with the river ; its surface from two to four 

 miles wide, curving from the river in entering Jeflferson county. The greatest extent of 

 exposed surface of this rock is in Lewis county; the next extent of exposed mass is in 

 Oneida, being the continuation of the surface in Lewis, from vyhence it extends into Herki- 

 mer, covering the greater part of the town of Russia, and a considerable portion of Norway. 

 It forms, in these two last counties, the dividing line between the Primary and the New- York 

 systems, ranging by the side of the primary ; the junction usually concealed by sand and 

 other alluvial products, these latter having been abundantly deposited, and heaped upon the 

 surface of the limestone. 



The greatest thickness of the Trenton limestone is in Lewis county, toward the northern 

 end, where it cannot be less than three hundred feet. It diminishes in thickness going east 

 and south, rarely exceeding thirty feet in any part of the Mohawk valley : it i§ not so thick 

 at the east as at the west end. The dark-colored mass in thin layers, separated by slate or 

 shale, is the kind which is met with in the Mohawk valley, and throughout Montgomery 

 county. In Lewis county, the upper layers are thicker, but often much intermixed with 

 shale, the Hmestone often in accretions, giving a rough character to the rock, and detracting 

 greatly from its value for all economical purposes, excepting for soil when decomposed. 



The grey variety of limestone docs not appear upon the Mohawk, nor in Montgomery 

 county, but it is abundant in the neighborhood of Holland Patent, the waters of Beaver 

 meadow, Trenton falls, Cincinnati creek, and the road thence to Boonville. In many parts 

 of Lewis county, the limestone shows a crystalline grain, and the color of portions of it is 

 Inclined to be grey. Where so much of the rock is exposed as in that county, and of such 

 great thickness, there must be locahties yielding as good a quahty of stone as in Oneida 

 county. The upper layers at Rathbone's, near Newport on West Canada creek, are of a grey 

 color, but rather of a fine-grained structure. The grey limestone, from often being in thick 



GBrt,. 3d Dist. 7 



