AMERICAN QUARTERLY JOURNAL 



OF 



AGRICULTURE AND SCIENCE. 



APRIL, 1846. 



AGRICULTURAL GEOLOGY OF ONONDAGA COUNTY. 



In the New York system, the Onondaga rocks occupy a centra) 

 position. Below them we find the whole of the inferior part of 

 the system, which has been called the Champlain division, as 

 well as the succeeding rock, the Medina sandstone. The same 

 may be said of a very large proportion of the Clinton group. 

 Those rocks which are above the Onondaga formation belong to 

 the superior part of the Erie division, and the whole of that mass 

 of shales and sandstones which form the Catskill mountains. The 

 thickness of the inferior sedimentary masses below those of the 

 county, cannot be less than three thousand feet, and those above 

 rather exceed this estimate. 



The base upon which the Onondaga formations repose, is the 

 Medina sandstone; a rock which skirts the shore of Lake Ontario 

 the whole distance from east to west. At the east, it is a harder 

 rock than the west, and furnishes but a small proportion of the 



Vol. III., No. IL 13 



