D. W. Barton on the Virginia Fluor Spar. 277 
Before the blowpipe they are partially fused, when a small 
fragment is employed. By the compound blow-pipe they 
are fused into a black glass, and burning particles are thrown 
off in various directions, resembling the scintillations of burn- 
ing iron. Repeated digestion with nitric acid separates a 
little lime. Melted with carbonate of potash, and the com- 
pound dissolved in boiling water, a dense white precipitate 
is separated, which is soluble in the stronger acids. The 
specific gravity of the crystals is from 3.31 to 3.37. 
2. Mr. D. W. Barron on the Virginia Fluor Spar. 
TO THE EDITOR, 
Dear Sir, 
I once gave you an imperfect description of the locality of 
Fluor in this vicinity. (Vid. V. 3, pa. 243 of this Journal.) 
Having lately examined it with more minuteness, I am ena- 
bled to communicate some additional facts which may not 
be wholly uninteresting. I visited the spot, accompanied 
by two of my former x (Messrs. Boyd and Rock- 
well, of Winchester, Ct.) for the purpose of excavating the 
ground, and ascertaining the position, extent, direction, and 
other circumstances of the vein. We penetrated to the 
hornstone with which the fluor is frequently connected. The 
vein is not so extensive as the number of detached masses 
near the surface induced us to believe. To the depth we 
have explored it, it is not more than twelve or fifteen inches 
wide. i am inclined however to believe, that it gradually 
enlarges as it descends, and that what we have discovered is 
only the clue which may serve to conduct the future adven- 
turer to one of nature’s rich and magnificent store-houses. 
With regard to the length of the vein it is impossible to form 
any other than a vague estimate. It may terminate within a 
ew yards of its commencement—It may traverse a consid- 
erable extent of country. 
he Fluor is found here of almost every variety of colour 
which ‘the mineral ordinarily assumes—white, greenish- 
Vor, IV......No, 2. 10 
