Classes of Rocks. 151 



8. First Graywacke. 



Subdivisions. Compact, overlying the inclined wacke 

 slate in a horizontal position, from Canada to near the High- 

 lands. Rubble, on the compact ; very perfect in the middle 

 of Rensselaer county, also two miles south of Albany. Vari- 

 ety. Chloride, in the highest $art of Rensselaer county. 

 Contents. Milky quartz, in the eastern part of Rensselaer 

 county. Calcareous spar and anthracite along the east 

 side of the Hudson from Fort Miller to opposite Newburgh. 



9. Sparry Limerock. 



Subdivisions. Compact, about New Lebanon Springs, 

 Slaty, three miles south of the springs on the Hudson turn- 

 pike. Variety. Checquered rock, on the Little Hoosick, 

 and near New Lebanon Springs. Contents. Chlorite and 

 Calc. spar, every where. 



10. Calciferous Sandrock. 



Subdivisions. Compact, Flint. Hill. Geodiferous, at Flat 

 Creek, west of the Noses. Varieties. Oolitic, near Sarato- 

 ga Springs. Sparry, at Flat Creek. Quartzose, on the 

 north side of the Mohawk, opposite Flat Creek. Contents. 

 Concentric concretions, near Saratoga Springs. Sulphate of 

 barytes and anthracite, on the West Canada Creek, six miles 

 above its mouth, also at Little Falls. Semi-opal, connected 

 with the quartzose variety. Brown spar and Hoimstone, at 

 Flint Hill. 



1 1 . Metalliferous Limerock. 

 Subdivisions. Compact, on East Canada Creek, Otsqua- 



ga Creek, and west of Little Falls. Shelly, Trenton Falls, 

 north of Utica, Glen's Falls, twenty miles north of Saratoga 

 Springs. Variety. Birdseye marble, is the compact, to which, 

 when polished, the vertical encrinites give a birdseye appear- 

 ance. 



12. Second Graywacke. 



Subdivisions. Compact, at Alexander's Bridge. Rubble, 

 ©n the top of the hill west of Schenectady, three miles. Va- 

 rieties. Grindstone, in Blenheim, Scoharrie county, N. Y. 

 and in Nova Scotia. Honeslate, in Rensselaerville, Albany 

 county. Red sandy, (old red sandstone ?) in Stephentown, 

 Rensselaer county, N. Y. near Dr. Elmore's. Contents. 

 Anthracite, near Alexander's bridge. Manganese Blcn- 



