228 MICA SLATE*— TALCOSE SLATE. 
belt of it runs north and south nearly through th^ 
centre of the state, striking north into New-Hamp- 
shire and Maine. It forms Saddle Mountain in 
Williamstown, near 4000 feet high, and the highest 
point in the state. The Taconic range, extending 
through Berkshire county, and south through Con- 
necticut and Dutchess county, is composed of mica 
slate, and so also is a great portion of the Hoosack 
Mountain range, which includes all the elevated land 
between the valleys of Berkshire and the Connecti- 
cut. It often approximates to argillaceous and tal- 
cose slate in Berkshire county, and is sometimes 
mistaken for them. The mica slate formations in 
New-England generally run north and south, and 
the strata, for the most part, dip to the east, with an 
angle of from 20 to 90 degrees. This rock is ex- 
tensively used for flagging the sidewaks of cities, as 
it is easily split into layers. 
Talcose Slate. — This is another of the primary 
rocks, and under it may be included chlorite slate 
and stealite, or soapstone, as these are only varie- 
ties of the same species. It is composed of talc 
and quartz, though it sometimes contains other in- 
gredients, as feldspar and hornblende. We find it 
connected with mica slate in New-England, as in 
the Hoosack and Green Mountain range, and very 
perfect specimens of it may be observed in Hawley 
and Plainfield. It also abounds in the Middle and 
Southern States. Steaite or soapstone abounds 
in the vicinity of the Rocky Mountains, where it is 
procured by the Indians for the bowls of tobacco- 
pipes ; also near the Falls of St. Anthony ; in Mary- 
land, near Baltimore ; in Pennsylvania, near Phila- 
delphia ; and Staten Island, where it forms a large 
proportion of the elevated grounds on the eastern 
part of the island. It is extensively employed for 
aqueducts, coal furnaces, &c. 
Granular Limestone, — There is no rock more ex- 
tensively diffused than this, and none more readily 
