475 
vegetable and animal substances. 
Oil of turpentine, purified with alcohol by Dr. Nimmo’s 
method, seems to approach to the constitution of naphtha, or 
of a mere carburet of hydrogen. Its specific gravity is 0.878. 
But as from the mode of preparing it, a minute portion of 
alcohol may remain in it, I do not think it necessary to in- 
vestigate its atomical structure. 
Naphtha, specific gravity 0.857, obtained by distillation 
from petroleum, is very nearly represented by. 
Carbon 22 atoms . 
. 16.50 . 
. 82.5 
Hydrogen 20 
. 2.50 . 
. 12.5 
Oxygen 1 — 
1.00 . 
. 5-o 
20.00 
100.0 
It therefore consists of 20 atoms olefiant gas, 1 atom car- 
bonic oxide, and 1 atom of carbon held in solution. 
Castor oil is an interesting unctuous body, from its great 
solubility in alcohol. It consists nearly of 
Carbon 7 atoms . . 5.25 . . 75.00 
Hydrogen 6 . . 0.75 . *. 10.70 
Oxygen 1 — — . . . 1.00 . . 14.30 
ITT" 'fnrr»mM.WRf ra a HTll If ill m m I 
7.00 100.00 
It is composed therefore of 6 atoms olefiant gas -j- 1 atom 
carbonic oxide ; or in volumes of 3 olefiant gas -{- 1 carbonic 
oxide. 
Alcohol, specific gravity 0.812, is composed very nearly of 
Carbon 3 atoms . . 2.250 . . 46.15 
Hydrogen 5 * — — . . 0.625 • • 12.82 
Oxygen 2 — — . . 2.000 . . 40.03 
4.875 100.00 
or, of 3 atoms olefiant gas = 2.625. 
2 water . = 2.25. 
