_Saponification._--For the purpose of determining the acids held in
combination in the oil in the form of esters, the oil was saponified
with alcoholic potassium hydrate by heating on a water bath with a
reflux condenser for one-half hour. Water was added to the mixture, and
the oil separated in a layer. After removing the excess alcohol on a
water bath, the alkaline solution was shaken out with ether to remove
any adhering oil. The remaining solution was evaporated to a small
volume, acidified with sulphuric acid, and distilled with steam.
The distillate from the above was extracted with ether and the ether
evaporated spontaneously. Only a trace of an acid residue remained,
which was neutralized with a solution of potassium hydroxid and
precipitated in three fractions:
Fraction 1. 0.1012 gram silver salt = 0.0893 gram silver = 88 per
cent silver.
Fraction 2. 0.0774 gram silver salt = 0.0637 gram silver = 82.3 per
cent silver.
Fraction 3. 0.0758 gram silver salt = 0.0502 gram silver = 66.2 per
cent silver.
The first two precipitates, when dried, consisted principally of silver
oxid, which, theoretically, contains 89.2 per cent of silver. A slight
excess of potassium hydroxid during neutralization was doubtless
responsible. Fraction 3 would seem to point to the presence of acetic
acid in the oil, silver acetate requiring 64.6 per cent of silver.
The aqueous acid portion remaining after the ether extraction was
neutralized with sodium carbonate concentrated to small bulk and
precipitated with silver nitrate in three fractions. Fraction 1
contained 76.2 per cent of silver; fraction 2, 77 per cent; and
fraction 3, 74 per cent. Since silver formate contains 70.5 per cent
of silver, a trace of formic acid is possibly present in the oil in
combination.
The esters of the oil, as shown by the above results, are present in
the oil principally as acetates, with a possible trace of formates.