62 
Indian Forest Records. 
[VOL. IV. 
APPENDIX D. 
I. 
The Reports on Pinus longifolia Oil from the Imperial Institute, 
London. 
Extract from tlie Interim Report of Professor Dunstan on the Com¬ 
position of Turpentine Oil from Pinus longifolia Resin. 
The following is an extract from the interim report on Indian 
turpentine by Professor W. P. Dunstan, M.A., E.P.S., Director, 
Imperial Institute, London, dated 27th July 1909: — 
“ The investigation of the constituents of the turpentine oil 
of Pinus longifolia was conducted on a sample from 
the Jaunsar Division, United Provinces, as this was 
found by preliminary examination to have undergone 
the least oxidation of the specimens forwarded from 
India. 
“The oil was colourless except for a very faint buff tinge. 
Portions of it, after having-' been dried by contact 
with dry sodium sulphate, had a specific gravity at 
15° C. of 0'869 as compared with water at the same 
temperature, and a specific rotatory power ( a ) D 
= - 3° 2'. 
“ A portion was distilled to remove the comparatively non¬ 
volatile matter, and the distillate was submitted to a 
long series of fractional distillations to separate the 
volatile constituents from one another. These distilla¬ 
tions were made under diminished pressure, approach¬ 
ing a vacuum, so that the boiling was effected at 
temperatures not exceeding 100° C. in order that the 
constituents might not be altered by the heat applied. 
“ The non-volatile matter amounted to about 6 per cent., but 
as the amount of non-volatile matter in turpentine 
oil slowly increases owing to atmospheric oxidation, it 
may have been less when the oil was first prepared. 
“ The volatile constituents were separated into two portions, 
differing considerably in their boiling points. The 
portion with the lower boiling point amounted to 
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