BIGSBY PALAEOZOIC ROCKS OF NEW YORK. 



337 



Speaking now of the framework which contains this basin, we find 

 that it is bounded on the east by the metamorphosed rocks of the 

 Appalachian chain of mountains, continued northwards into New 

 York, Massachusetts, Vermont, and Canada, and in reality contem- 

 poraneous with the sedimentary strata they encompass. 



On the north the central basin or area is sustained unconformably 

 for 2000 miles westward by the Laurentine chain of hill-ridges, which 

 consist of gneiss, syenite, marbles, &c, of a metamorphism more 

 ancient than the eastern framework of the basin, and which stood 

 above the Silurian seas to represent the primal nodus or nucleus of 

 the Western Hemisphere long before, and during, the palaeozoic ages 

 which we hope to describe, and when elsewhere all was sea. 



An observer starting southwards from the Laurentine chain, as 

 from Kingston on Lake Ontario, would encounter the sedimentary 

 strata in succession from the oldest, until, in Pennsylvania or Ohio, 

 he would stand on wide-spread masses of coal-measures, — each fresh 

 stratum marked by a beach, ridge, or some local feature, and re- 

 stricted to a narrow band, or outspreading far and wide, according 

 to the accidents of the ground. 



Tabular Arrangement of the Palceozoic System 

 Upper ...Old Red Sandstone V. 



of the State of New York. 

 Conglomerate and Sandstone. 



r ^Slr::::::::::: } IV - ^— *— 



Q 



Middled Genesee Slate .. 

 Tully Limestone 

 Hamilton Rocks 

 Marcellus Shales 



III. Clay and Sandstone. 



Lower •> 



Coniferous Limestone 

 Onondaga Limestone 



}"• 



Schoharie Grit 



Cauda-galli Grit 



Oriskany Limestone 



Limestone. 

 Sandstone. 



M 



Upper Pentamerus Limestone 

 Delthyris Shaly Limestone ... 

 Lower Pentamerus Limestone 



Waterlime Rocks 



Onondaga Salt Rocks 



Coralline Limestone "I 



Niagara Shales and Limestone... J 



Clinton Rocks \ 



Medina Sandstone J 



Oneida Conglomerate 



"Hudson River Rocks \ 



Utica Slate J 



Trenton Limestone "1 



Lower ■{ Birdseye Limestone )■ 



Chazy Limestone J 



Calciferous Sandstone 1 



Potsdam Sandstone J 



Upper < 



Middle 

 Transition 



H. Limestone. 



G. Sandy Shale. 



F. Limestone. 



E. Sandstone. 



D. Quartzose Conglomerate. 



C. Clay. 



B. Limestone. 



A. Sandstone, 



