128 



JVo Coal in the JYew York Rocks. 



[Sept., 



PROF. Eaton's classes. 



1. Primitive Class. 



Granite • 



Gneiss 



Horneblcnde rock 

 Mica blate 

 Talcose rock 

 Granular quartz 

 Granular limestone 

 Sparry limerock 

 Primitive argillite 



2. Transitive Class. 



Transitive argillite 



Calciferous sandrock 



Metalliferous limerock 



Graywacke 



Old red sandstone 



Secondary Class. 

 Millstone grit 

 Saliferous rock 

 Gray band lerriferous slate 

 Ferriferous sandrock 

 Calciferous slate 

 Geodiferous limerock 

 Cornitiferous limerock 

 Pyritiferous rock 



Remark.— The pyritiferous 

 rock embraced the whole 

 series from the Ononda- 

 ga limestone to the base 

 of the old red sandstone 

 of the Catskill mountain. 



PRESENT CLASSES OR SYSTEMS. 



1. Primary Rocks. 



Same as opposite column, 

 except those numerated in 

 the Taconic system. 



2. Taconic System. 



Granular quartz 



Magnesian slate 



Granular limestone alternat- 

 ing with Magnesian slate 



Sparry limestone 



Taconic slate, and subordin- 

 ate beds of impure lime- 

 stone 



3. JYew York System. 



Potsdam sandstone 



Calciferous sandstone 



Chazy limestone, and Birds- 

 eye Trenton limestone 



Utica slate 



Lorraine shales 



Gray sandstone 



Medina sandstone 



Onondaga salt and plaster 

 rocks 



Maniius water lime 



Pentamerus limestone 



Dekhyris shabby limestone. 



Encrinal limestone 



OrisUany sandstone 



Caudagalli grit 



Onondaga limestone, and 



Corniferous limestone 



Marcellus slate 



Hamilton slates and shales 



Tully limestone 



Genesee slate 



Portage and Chemung sand- 

 stones and shales 



Old red sandstone 



Conglomerate of the coal 

 formation 



