PRIMITIVE LIMESTONE* 229 
detected, as a single drop of acid will cause an ef- 
fervescence. Its structure and appearance are too 
well known to need description. It forms an ex- 
tensive bed through the whole extent of Berkshire 
county, and thence it stretches through Vermont far 
north into Canada. The same range also extends 
south through the State of Connecticut, where in 
many places it is burned for lime. It also abounds 
in New-Hampshire and Maine, and, indeed, in all 
the states where the other primitive rocks are 
found. Professor Hitchcock regards the Berkshire 
deposite as one of the most extensive ranges of 
primary limestone in the world. It is of a pure white 
colour and of a highly crystalline texture, as may 
be seen by examining the City Hall in the city of 
New- York, which is built of this stone ; or the Gi- 
rard College, Philadelphia. Blocks are obtained 
from a ledge in Sheffield more than 50 feet long and 
eight feet thick. We shall hereafter speak of the 
economical uses of this valuable rock. 
The non-stratified or granitoid rocks, as they have 
been called, contain, among others, the following 
minerals, viz., iron, tin, zinc, plumbago (black lead), 
titanium, molybdena, lead, copper, gold, beryl, gar- 
net, topaz, tourmaline, zircon, chrysoberyl, pyrox- 
ene, hyperstene, spinelle, epidote, pinite, idocrase, 
diallage, &c. The same minerals are also found in 
the stratified rocks ; and, in addition, anthracite coal 
has been met with, though not in large quantities, 
as at Worcester, Massachusetts, in mica slate.* 
* It is claimed by some geologists that this is a transition 
formation. 
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