CAMPHORIFEROUS ESSENTIAL OILS, ETC. 
from its being supposed to bear the same relation to the volatile 
oils, asstearine does to the fixed oils. Dumas,* however, has 
analyzed several of these deposits, the analysis resulting in 
the fact that they are species of camphor, differing from the 
true, in containing more or less hydrogen, while the oxygen 
remains the same in all of them. He has also informed us that 
the second class of essential oils may be considered as solu- 
tions, in various proportions of these camphorous bodies, in 
liquid carburets of hydrogen. That these carburets are not 
all identical in composition, is evident from the constitution 
of the camphors analyzed by Dumas. 
Camphor of oil of peppermint, C 10 H l0 +0. 
true, C 10 H 8 + 0. 
of oil of anise, C 10 H 6 + 0. 
Camphor of Cinnamon, when pure, is a white substance, 
which is deposited from oil of cinnamon by long standing 
and exposure. It crystallizes in flattened oblique rhombic 
prisms, with truncated edges; soluble in alcohol and ether, and 
fuses at 248 degrees, Far.; at which temperature it volatilizes 
rapidly, boils at about 420 Far. without decomposition, and 
crystallizes on cooling. 
It would have been an interesting link in the chain of 
discovery, had Dumas, while investigating the camphors, 
also given an ultimate analysis of the camphor of cinnamon. 
It will probably be found to bear a near proportion to those 
already spoken of. 
It has been observed that volatile oils increase in specific 
gravity by age and exposure, and this is accounted for by 
their absorbing oxygen. The difference between a camphor 
and a resin is. the greater proportion of oxygen entering into 
the composition of the latter. I have observed that these oils 
are differently disposed, as regards the absorption of oxygen; as, 
for instance, those of cinnamon, peppermint, anise, &c. yield 
crystalline camphors, while those of juniper, copaiba, &c. 
yield true resins. As an example, a bottle of oil of cassia, 
* Annal. de Chimie et du Phys. vol. 1. 235. 
