626 
The Philippine Journal of Science 
1921 
As shown by the figures in Table 1, lumbang oil contains 93.04 
per cent of liquid unsaturated acids and 2.73 per cent of solid 
acids. These figures are the average of the results obtained 
from two closely agreeing duplicate analyses. 
The liquid unsaturated acids were separated and estimated by 
the bromp-derivative method of Eibner and Muggenthaler, 17 
which is based upon the different solubilities of the bromine 
derivatives of the liquid acids. We followed, in general, the 
directions given by Lewkowitsch, performing duplicate experi- 
ments. About 4 grams of the liquid acids were dissolved in 40 
cubic centimeters of dried purified ether. The ethereal solution 
was then cooled, treated with bromine, and allowed to stand 
about three hours at —10°. The solution contained a crystalline 
precipitate (ether-insoluble bromide) , showing the probable pres- 
ence of linolenic acid, since linolenic hexabromide is insoluble in 
ether. The solution containing the precipitated bromide was 
then filtered through a weighed filter paper which had been pre- 
viously dried and kept in a desiccator. The filtrate from the in- 
soluble bromide was set aside and investigated after the work on 
the insoluble bromide was completed. The insoluble bromide 
was dried at 50° and weighed. When treated with benzene the 
insoluble bromide dissolved completely, showing the absence of 
any octobromides, since the octobromides likely to be present are 
insoluble in benzene. The crystals obtained by evaporating the 
benzene solution gave the figures which are compared with the 
corresponding data for linolenic hexabromide in Table 2. 
Table 2. — Compound from lumbang oil and linolenic hexabromide. 
Compound. 
Melting 
point. 
Bromine 
content. 
Compound from lumbang oil 
°C. 
178.5 
Per cent . 
63. 59 
63.32 
Linolenic hexabromide 
180.0 
The bromine content was determined by boiling about 0.1 
gram of the crystals with about 0.5 gram of solid silver nitrate 
and 30 cubic Centimeters of pure concentrated nitric acid. The 
precipitated silver bromide was collected on a Gooch funnel. 
The figures given above show that these crystals were lino- 
lenic hexabromide and that lumbang oil contains linolenic acid as 
linolenic glyceride. 
17 Lewkowitsch, J., Chemical Technology and Analysis of Oils, Fats, and 
Waxes 1 (1913) 568 to 578. 
