152 Professor Hausmann on the Metal of Carbon. 
Silicie acid, : ° - 50.8 
Magnesia, . : : - 26.5 
Lime, : A 5 c 0.7 
Alumina, C ‘ : . 9.4 
Perox. of iron, . 5 5 2.0 
Water, : 5 : » 10.6 
99.9 
Is Graphite the Metal of Carbon? By Professor Hausmann 
of Gottingen. 
I nave to thank the kindness of Professor Wohler for a re- 
markable variety of Graphite from Ceylon, which he lately 
found in the possession of an apothecary. It is of the foliated 
kind, has a thick columnar structure, and shews in some 
places a tendency to individual crystalline development. Jn 
the pieces now lying before me, the length of the columnar 
portions is two Parisianinches. They are partly straight and 
uniform, partly bent. The pieces are bounded by parallel sur- 
faces, in regard to which the columns are either at right angles 
or somewhat obliquely placed; and it is not improbable that 
they were obtained from a vein. The individual columns af- 
ford longitudinally an extremely perfect cleavage, to the small- 
est lamella. By inserting the knife in one end of the columns, 
thin stripes may be taken off along the whole length, which 
retain their continuity, and become bent in a curved manner, 
just as bark may be peeled froma young branch. The breadth 
of the folia depends on the size of the distinct concretions, and 
generally measures from a half to two lines. The cleavage 
surfaces have a high lustre, and are quite brilliant. When we 
examine them under a lens, we perceive on them sometimes 
lozenge-shaped perpendicular fissures, that seem to indicate 
concealed cleavages which cut the principal ones at right an- 
gles, and have previously been noticed in Graphite. If we 
place one of the separated folia on an anvil, it can be made 
somewhat thinner and larger by hammering, which property 
(not, I believe, hitherto observed), in combination with the per- 
fect opacity of its thinnest folia and its electrical characters, 
