78 
Indian Forest Records. 
[Vol. rtf. 
saucers and is exposed to sunlight from 10 to 30 days according 
to the weather. Exposed to the bright sunlight of moderate heat, 
the amber coloured rosin, for example, becomes gradually clearer 
in colour, finally becoming almost colourless and transparent. 
Kosin is generally overburnt in the still if turpentine distillation 
is completely carried out. After a cal- 
dlffeient mefchods culated amount of oil has distilled over, 
it is best to “cut” the still. For finer 
grades of rosin it is essential to leave some amount of the oil in it, 
which can be driven off by heating it over an open fire. Usually 
the still is “ cut 55 at a point when the distillate approximates to 
one part of turpentine and 9—10 parts of water. At this stage only 
a negligible quantity of oil is left in the still. Any attempt to 
distil this last portion of the oil darkens the colophony. In 
America, when “Virgin Dip” is under distillation, the still is 
“ cut ” even earlier. 
A great deal, as said above, depends on the process of distilla¬ 
tion, which if carried on at a low temperature gives better qualities 
of both the oil anl the rosin. For example, rosin obtained in tur¬ 
pentine distillation by furnace heat only is of inferior quality and 
often dark coloured and smoky. (J. L. Figot, Deport on the manu¬ 
facture of spirits of turpentine and colophony, 1897.) It is due 
to the fact that La this process the crude resin has to be heated to 
158° C- and more. The rosin obtained from turpentine distillation, 
where both the furnace heat and the superheated steam are employed 
is of better quality than that obtained in the process mentioned 
above or in steam distillation of turpentine where the temperature 
is kept at about 150° C. by letting in steam at a pressure of 4*7 
kilograms per square centimetre, both into the steam jacket con¬ 
taining crude resin and into the steam coil inside the jacket. (See 
J. L. Pigot, loc. cit.) 
Water distillation, however, is the only process that has been 
adopted up to very lately in India.* This process lies between the 
furnace heat process and steam distillation. (For the description of 
the latter two processes, see J. L. Pigot, loc. cit., and of the former 
process, see Chapter I, Part I of this Note.) At Bhowali, where 
* It is understood that steam distillation has very recently been tried near 
Lahore, but the results are not yet available. 
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