54 
Indian Forest Records. 
[Vol. IY. 
The free acids formed corrode the copper of the appa¬ 
ratus and the copper salts so produced discolour the dis¬ 
tillate, which becomes at times green and at times blue. 
If the distillate becomes discoloured, it must be redis¬ 
tilled and decolourized before it is mixed up 'with the 
rest of the stored oil. 
(6) To avoid complaints being made regarding the variations 
in quality, it is recommended that suitable storage 
tanks should be established in both the departmental 
factories to collect the distillates from different 
charges and thus to make them all of a uniform 
quality. 
It is hoped that the suggestions made above will prove of some 
value. It is possible that even when effect has been given to the 
recommendations made above, complaints may still be forthcoming 
from the buyers of the oil. The oil could be refined to any degree 
if such complaints were well grounded and the price offered by those 
from whom they proceed were to warrant extra rectification. The 
writer believes that no complaint can legitimately be made against 
the Bhowali redistilled oil as regards its quality for the purposes 
of painting and varnishing. But the painters and varnish-makers 
are known to judge a sample of turpentine oil by its odour, and 
ihe slight variations from the odour of the standard turpentine 
constitute in their judgment a sufficient cause for rejection of 
the sample. The story is related of a buyer of a leading 
American Yarnish Company to whom a sample of nearly chemi¬ 
cally pure pinene was sent for valuation and who returned it as 
not satisfactory. It is said that he opened the cork and instead of 
testing the oil he simply brought the mouth of the bottle close 
to his nose and passed judgment on the odour. Mr. Harper* says 
that this pure oil could not be duplicated at less than twice the 
price of ordinary American turpentine. This story is related here 
to show that it is difficult to convince painters and varnish-makers 
of the merits of really good turpentine oil. 
In connection with the drying capacity of the turpentine oil, 
it may be noted here that old oil without doubt causes varnishes 
to dry more quickly than freshly distilled oil. This is so because 
* W. B. Harper, MS.—the Utilization of Wood Waste by Distillation, page 117. 
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