93 
tion in nitric acid. From the experiments of 
Gehlen, it appears to consist of the elements of oil 
of turpentine, carbon, hydrogene, and oxygene, 
united to the elements of muriatic gas, chlorine 
and hydrogene. 
From the analogy of artificial to natural camphor 
it does not appear improbable, that natural cam- 
phor may be a secondary vegetable compound, 
consisting of camphoric acid and volatile oib 
Camphor is used medicinally, but it has no other 
application. 
15. Fixed oil is obtained by expression from 
seeds and fruits; the olive, the almond, linseed 
and rape-seed, afford the most common vegetable 
fixed oils. The properties of fixed oils are well 
known. Their specific gravity is less than that of 
water; that of olive and of rape-seed oil is *913 ; 
that of linseed and almond oil *932 ; that of 
palm oil *968 ; that of walnut and beech-mast oil 
*923. Many of the fixed oils congeal at a lower 
temperature than that at which water freezes. 
They all require for their evaporation a higher 
temperature than that at which water boils. The 
products of the combustion of oil are water and 
carbonic acid gas. 
From the experiments of Gay Lussac and 
Thenard, it appears that olive oil contains, in 100 
parts, 
Carbon - - 77*213 
Oxygene - 9’427 
Hydrogene - - 13*360 
This estimation is a near approximation to 1 1 
