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NEW YORK STATE MUSEUM 



the mouth of which is just above the Oobleskill, and Becker's 

 cave below Lasell park, the entrance to which is in the Manlius 

 above the waterlime. Numerous other caves occur in this rock 

 in eastern New York. Caverns are much less frequent in the 

 coarser grained limestone, though fissares of considerable width 

 are common. They generally open to the surface however. It 

 seems that the lime mudrocks are more readily dissolved than 

 the lime sandrocks which generally are more or less crystalline 

 and that furthermore the thin bedded character of the rock is 

 more favorable to the passage of underground water than is the 

 coarse massive-bedded lime sandrock of the higher formations^ 

 In the western part of the State of New York the Siluric 

 (Ontaric) section is as follows, the thicknesses given being those 

 found in the Niagara section. 



Devonic Onondaoa limestone 



Cayugan 



iluric 

 or _ i 

 Outanc 



Hiatus 



CobleskilP (Bullhead) limestone 



Bertie waterline 



Camillus shale 



Syracuse beds . . 



j Yernon shale 

 iPittsford shale 



Guelph doioniites 



Lockport dolomite 



Eochester shale 



_ Clinton beds 



r Medina sandstones 



Oswegan ^ Medina shales and sandstones 

 t Oswego sandstone , 



Niagaran 



FEET 



7-8 

 60 



150 

 35 



200 



200 



75 



40 



125: 



1140: 

 75: 



Champlainic Lorraine shales 



In central New York the Oswego sandstone merges into the 

 Oneida; a pure white quartz pebble conglomerate. At Washing- 

 ton Mills, Oneida co. this conglomerate rests directly on the 



^The name Greenfield limestone has been used by tbe author for this 

 western type of the Cobleskill, from Greenfield O., where it 1» well de- 

 veloped. Science, Dec. 2, 1898. v.8, no.205, p.800. 



