622 The Philippine Journal of Science 1921 
about eight months after the sample had been prepared. The 
results obtained in this investigation really represent the condi- 
tion of the oil after storing. ; 
The sample of lumbang oil used in this investigation had a 
saponification value of 214, and an iodine value (Hiibl) of 140. 
Both the saponification and the iodine values were determined 
according to the method of Lewkowitsch.°® 
The specific gravity of the oil °C. fi was 0.9206. 
COMPOSITION 
Lumbang oil is a quick-drying oil and resembles linseed oil and 
Chinese wood oil (tung oil) in its general properties. These 
three oils have somewhat similar constants and are characterized 
by high iodine and saponification values. Although the exact 
composition of both tung and linseed oils is still somewhat un- 
certain, it is generally believed that tung oil consists chiefly of the 
- glycerides of oleic and elaeomargaric acids, while linseed oil 
contains linolenic, linolic, a small percentage of solid acids, and 
possibly oleic acid. The composition of tung oil is therefore quite 
different from that of linseed oil. Since both tung and lumbang 
oils are obtained from the same genus, Aleurites, we were inclined 
to think that probably lumbang oil had a composition more like 
that of tung than linseed oil and, like tung oil, contained elaeo- 
margaric acid. We therefore tested our sample of lumbang oil 
for the presence of elaeomargaric acid. In making this test we 
used the method of Schumann * which depends upon the fact that 
elaeomargaric acid has the property of crystallizing in rhombic 
flakes from dilute alcohol solution at 0°. We did not obtain any 
crystals and examination of the solution under the microscope 
showed the entire absence of crystals. 
Tung oil when tested by the bromo-derivative method of 
Eibner and Muggenthaler* gives no crystalline precipitate of 
ether-insoluble brominated glycerides, whereas linseed oil gives 
a copious precipitate amounting to about 38 per cent. This test — 
is regarded as an important test for the purity of linseed oil. We 
tested our sample of lumbang oil by the bromo-derivative method 
and found that, like linseed oil, it also yields a large crystalline 
* Lewkowitsch, J., Chemical Technology and Analysis of Oils, Fats, and 
Waxes 1 (1913) 380 and 397. 7 
* Schumann, C. L., Journ. Ind. Eng. Chem. 8 (1916) 9. 
* Lewkowitsch, J., Chemical Technology and Analysis of Oils, Fats, and 
Waxes 1 (1918) 568-578. 
