Part I.] Puran Singh : Turpentine Oil and Indian Rosin. 53 
the distillate of 57 lbs. (the yield of oil from 300 lbs. 
of oleo-resin) should be divided into four fractions, the 
first three being of about 15 lbs. each and the last 
of 21 lbs. and only the fourth fraction should be 
redistilled in a separate copper still, stopping the 
redistillation when 75 per cent, of this charge has been 
recovered. 
To put the last fraction back into the still used for the distilla¬ 
tion of oleo-resin, though no doubt more convenient, is 
not recommended. This plan is worthy of trial on a 
commercial scale. 
To improve further the quality of the oil the whole of the 
crude oil may be redistilled once or twice if the demand 
warrants this. Evidently repeated distillation will be 
unnecessary if the oil so produced does not command 
a much better price. 
There can be no reason, however, why the redistilled Bhowali 
oil made “ extra fine by rejecting a total of 20 per 
cent, of crude oil should not command a much better 
price than the present oil, and it is, therefore, recom¬ 
mended that steps should be taken to manufacture the 
“ extra fine ” quality and secure a proper market for it. 
(5) Rapid distillation should be avoided and care should be 
taken that the temperature inside the still be not so 
high as to cause the emission of yellowish fumes, 
which can be noticed by opening the charge hole 
from time to time, otherwise the distillate will be very 
acidic and sticky owing to the presence of the resin 
and its decomposition products, rosin oil, etc-, which 
are carried over into the distillate. In such cases 
whenever yellow colouration is observed in the fumes 
issuing from the still, the whole distillate result¬ 
ing from the charge must be redistilled before it is 
mixed up with the preceding distillate. 
An additional reason for avoiding too high a temperature is 
the fact that excessive heat has an injurious effect on 
the apparatus, and on the quality of the oil and rosin. 
[ 53 ] 
