Chemistry and Physics. 275 
The formula of the body thus obtained is C22H40i10, or, as the author 
writes it, C1H4Os. 
Its crystals belong either to the right or oblique prismatic system. It 
is insoluble in water, containing acids or salts, and very slightly soluble 
in pure water. It unites with alkalies, and the crystals have an acid 
' ion; ammonia converts it into a transparent jelly, but the substance 
isnot dissolved. Acids separate it from this combination, as a gelatinous 
__ Inass resembling silica. ‘Treated with deoxydizing agents, it is readily 
mposed. When a solution of sulphate of ammonium or of potas- 
Os, 
The 
__ ores CosHsOu become GraHsOs, GrsH204 and GraHsOun, 
cording to the law of Dulong and Petit, the specific heats of the 
dements are inversely as their ccniviceiil The elements are divided 
Into two classes, one in which the product of the specific heat into the 
sitivalent is about 3°3—the other in which this product is 66. The 
*Pecific heat of carbon in the form of graphite—0°20187—presents a re- 
: ity exception 'to the law, if we take its equivalent as 6- or 12, but 
dine Sme the atomic weight of graphite as 83, we have for the pro- 
of the specific heat into the atomic weight, the number 6°6 which is 
et to the law of Dulong and Petit. : he 
and 5; relation which exists between the atomic weights of boron, silicon 
Pe hisat ~ that form of carbon for which - oo may be a gone : as 
.» .°t €lement, graphon, is precisely the kind of numerical relation 
wich is found to ade keboaih te weighte of analogous elements, We 
Vir REE seer, 
