Determination of Carbon in Graphite. 357 
Veins of asbestus. Between the plates are occasional thin part- 
ings of bfown siliceous matter, but the body of each crystal ap- 
pears to be perfectly pure graphite. 
Six grains of this material reduced to an extremely fine pow- 
der with the granular quartz, yielded by oxydation, carbonic 
acid, 20°76 grains. A second experiment with a like quantity 
gave, carbonic acid, 20-82 grs. 
From the near coincidence of these results, we may safely as- 
Sume the mean 20-79 as a basis for computing the carbon in the 
mineral. We infer therefore that this graphite contains in 100 grs., 
carbon, 94-5 grs. , 
Native Graphite, (b.)—This is a compact massive variety, 
from Cumberland, seemingly very pure 
Six grains yielded, in two successive experiments—first eX- 
Periment, carbonic acid, 20-35 grs.; second experiment, carbonic 
acid, 20°31 grs. Assuming the mean 20°33 for computation, we 
have in 100 grs. of this graphite, carbon, 92°4 grs. 
_ Native Graphite, (c.)—A portion of the massive variety asso- 
Giated with (a.) It contains earthy matter and interspersed scales 
of mica, with grains of partially decomposed felspar. 
Six grains treated as before, yielded, carbonic acid, 14°36 grs. 
This corresponds in 100 grs. of the graphite, to carbon, 65:4 grs. 
In all these experiments the oxydation was completed in about 
thirty minutes. : 
Kish, (a.)—This material was in very thin crystalline plates, 
not acted on by the magnet. 
Six grains in two successive experiments gave—first, carbonic 
acid, 20-50 grs.; second, carbonic acid, 20-42 grs. The mean of 
a. results, 20-46 grs., corresponds in 100 grs. of the kish, to 
n, 93 grs. ; 
_ Kish, (b) This specimen was in larger flakes, with adhering 
ton and slag. Before submitting it to experiment, it was digest- 
ed for some hours in hydrochloric acid to remove the iron, and 
