Geology and Mineralogy of a part of Massachusetts, &c. 15 
exquisite polish, have been found, which are supposed to 
= a superior quality of marble at a greater depth. 
is a common remark of the workmen, that the quality 
auaibes as its depth increases. 
The elastic marble of Lanesborough and West-Stock- 
bridge has long attracted the attention of mineralogists. 
The artificers consider it a poorer kind of marble, 
compact and fine; and some of them have made the re- 
— that most of their coarser marble is somewhat elas- 
“The value of the marble annually wrought in the coun- 
ty of Berkshire, is estimated at about $40,000. Travel- 
lers who have not been accustomed to such abundance of 
this beautiful mineral, have often admired the multitude 
of white marble monuments in our church-yards, and ex- 
pressed their surprise at its commonness in ordinary 
dwelling houses. 
here the limestone joins the mica slate, the two often 
run into each other, forming, with the quartz and some- 
times tale mingled with it, a singular aggregate, scarcely 
capable of being named, and not worth the t 0 
ing it. Near. Williams College, is a bed of limestone 
which contains a large proportion of quartz. It is a fine- 
grained, compact mineral, harder than the true granular 
limestone, and sometimes much divided by neguier “a 
which are Sik with tale. This bed may a d for 
ibe distance of two miles—white and gray —an ofteit di- 
vided by natural seams into rhombordal masses Fs various 
dimensions. 
Caverns are said to be uncommon in granular limestone. 
In this section, however, are several. They are at Ben- 
crystalline calcareous qe and stalactites and 
ries eg are found in them. e caverns at Benning- 
ton and New- tte iniokgh have several rooms, some of 
onal are large. That at Lanesborough is a long and 
a passage at a lower depth 
nular limestone alternates several times in this 
section with mica-slate. The alternations in Salisbury, 
Con. were noticed by Prof. Silliman, Am. Journ. Vol. II. 
p- 211. 
