Indian Forest Records. 
[Vol. IY. 
CHAPTER 111. 
Steam Distillation* versus Water Distillation. 
It was lirst proposed to determine to what extent the quality 
of turpentine oil was improved by replacing the present method of 
distillation by the steam distillation process. Accordingly two 
samples of crude oleo-resin, one from the Jaunsar Division and the 
other from Naim Tal, were subjected to steam distillation in a 
small steam still in the laboratory with results detailed below: — 
Jaunsar sample .—-This oleo-resin gave 20 per cent, by weight of 
turpentine oil. On fractional distillation, the latter gave the 
following fractions: — 
Steam distilled turpentine oil. 
(Kalsi.) 
160°—165° C. 
165°—172° C. 
172°—180° C. 
180°—200° C. 
Residue above 200° C. 
25-5 per cent. 
39 0 
13-0 
12-5 
The steam distilled oil rectified by redistillation gave the 
following fractions : — 
Up to 165° C. ..... 80 per cent. 
165°—172° C.15 
Residue above 172° C. . . . . . 5 „ 
The specific gravity of the redistilled 
0-8635 at 22° C. 
oil was found to be 
* Steam distillation mentioned here consisted in passing steam into the resin placed 
in a steam still gradually heated to about 140° C. and distilling off the whole of the 
turpentine oil at that temperature. It was found that the total* yield of the oil 
could not be obtained in the Laboratory below that temperature. According to 
various authorities, the temperature of the resin even in superheated steam dis¬ 
tillation process has to be raised to 150° C. when distillation is done on a large scale. 
[ 14 3 
