70 Crystallographic Examination of Eremite. 
going on, the heat be suffered not to fall below the boiling point of 
quicksilver, and the condenser be observed to contract, it is a sure 
sign that evaporation is no longer going on and that distillation is 
perfect. _ 
But if the condenser be unscrewed, and the tips of the beak be 
supposed to remain immersed in water, as soon as the pressure 
from within (whether by cooling, or from the absence of a fluid to 
supply vapor,) becomes less than that of the atmosphere with- 
out, the water is forced from the bucket through the tube into the 
alembic, and if the quicksilver be not all evaporated it is wasted, 
and the alembic is endangered by the concussion and sudden cooling 
produced within, by the cold water and steam. ‘Therefore as soon 
at the condenser contracts, the alembic should be removed from the 
fire, the condenser taken out of the bucket and unscrewed, and the 
alembic be suffered to cool in the air. 
This alembic has been in use at one of the Virginia mines for the 
last ten or twelve months, and when properly luted, the weight of 
the gold and quicksilver after distillation has invariably equalled that 
of the amalgam which they formed previous to the operation. It 
does away with the necessity of settling and pouring off, or straining, 
and saves all the gold and quicksilver lost in the common way of 
“¢ blowing off.”’ 
Art. VI.— Crystallographic Examination of Eremite; by James D. 
Dana, A.M., Assistant in the Department of Chemistry, Miner- 
alogy, &c. in Yale College. 
[Read before the Yale Nat. Hist. Society, June 19th, 1837.] 
Ar our last meeting we were informed by Mr. Thos. R. Dutton, 
that he had discovered in a bowlder at Watertown in this State, a 
few crystals of a mineral, which Prof. C. U. Shepard on examina- 
tion had announced to be an undescribed species ; and that Prof. S. 
had consequently described it as new under the name of Eremite. 
Through the kindness of Mr. Dutton, I have examined other crys- 
tals in addition to the one investigated by Prof. S. and thus am en- 
abled to add farther confirmation of the conclusion that the speci- 
mens belong to a species hitherto unknown. 
The crystals are all of them small. The largest is but one fifth 
of an inch long; the others vary in length from one sixteenth to one 
