3 
<c3#.9 
Tn 11* ' 
V,4 
Part I.] Puran Singh ; Turpentine Oil and Indian Rosin. 
rectification by redistillation until on fractional distillation it 
would nearly all pass over below 167°—170° C. Some trouble was 
taken to find out if any portion of the 35 per cent, could be utilized. 
An oil of fairly good quality was produced by redistilling tlie 
last portion of the crude oil to the extent of 75 per cent, and mixing 
it with the first three parts of the crude distillate. An oil was thus 
obtained which had only 9 per cent, of that heavy residue distilling 
above 172° C. This oil sold at a fairly good rate, but certain pur¬ 
chasers still rejected it as unsuitable. A market w T as also found for 
the heavy turps contained in the crude oil, as it could be used for 
the manufacture of printing inks. 
Af.er preliminary work on redistillation, most of which was 
done in conjunction with Mr. P. H. Clutterbuck at Bhowali, the 
enquiry was pushed further with a view to finding out some better 
method for distilling Finns longifolia resin at low temperatures. 
It was observed that it is in the process of distillation whether by 
water or by steam, both of which have to be necessarily carried out 
at high temperatures to secure the total yield of oil, that the more 
labile constituents of Chir oil change into higher terpenes under the 
influence of excessive heat, resulting in the deterioration of the oil. 
No attempt seems ever to have been made on a commercial scale in 
India to produce this oil in its purest form. A suitable method 
was devised for distilling the oil in its original purity in the 
Laboratory of the Forest Research Institute. The fractional dis¬ 
tillation of the oil, which was obtained by distilling a mixture of 
crude resin with a small quantity of acetic acid or methylated spirit 
bjr steam at a temperature of about 100° C., confirmed the fact that 
it was the high temperature at wdiich distillation is carried out that 
spoils the oil. The oil thus distilled had only about 4—6 per cent, 
ot turps which distilled above 167° C., which, as said above, in the 
case of water-distilled crude oil amounted to 35 per cent., boiling 
above 172° C. It was thus proved that the quality of the oil mainly 
depends on the temperature of the still; the lower this is kept the 
better the quality of the oil. This laboratory method was tried 
on a fairly large scale at Bhowali and a fairly large quantity of the 
oil was distilled at 100° C. by using an ordinary and somewhat 
crude form of still. The commercial opinions received were fairly 
encouraging. 
631114 
