16 Indian Forest Records. [Yol. IV. 
The turpentine oil as turned out at Bhowali (Naini Tal) (specific 
gravity.at 30° C. = 0'869) gave the following fractions : — 
Crude turpentine oil distilled at Bhowali , 
(IN’aini Tal.) 
160°—165° C. 
165°—172° C. 
172°—180° C. 
180°—200° C. 
Residue above 200° C. . 
27-5 per cent. 
32-5 „ 
17 *5 „ 
9-0 „ 
13-5 „ 
The yield of turpentine oil at Bhowali is between 19—20 per 
cent, by weight. 
It will be evident from the above figures that the quality of the 
crude oil from both processes is nearly the same, but the oil recti¬ 
fied by redistillation is really much lighter than the crude oil and 
is of a uniform quality. About SO per cent, of this rectified 
passes below 165° C.* But it will be shown later on that the crude 
oil obtained by water distillation can also be improved to the same 
standard, by means of redistillation. 
Colophony, as obtained from steam distillation, appears to 
contain a greater amount of moisture and less of other volatile 
matter than the colophony obtained by the water distillation 
process, and, therefore, if the former were gently heated on an open 
fire for some time, it would be quite as good as the imported stuff. 
There is very little difference in the two samples in their acid and 
saponification numbers. (See Part II of this Note.) 
Water distillation. —In this process, the temperature of the still 
charged with crude oleo-resin is raised to 165°—175° C. before the 
distillation actually begins. As soon as the oleo-resin is brought to 
boiling point, a thin stream of water is admitted, which consider¬ 
ably reduces the temperature of the still The water thus is at 
once converted into steam, which is given off with large volumes of 
turpentine vapour, and the distillation commences at a much lower 
* Gildmeister and Hoffman : “ Volatile Oils,” page 246. 
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