630 
The Philippine Journal of Science 
1921 
The percentage of solid acids (2.73) calculated as stearic 
glyceride gives the figure 2.85, which really represents the per- 
centage of glycerides of the mixed solid acids. 
According to our investigation, lumbang oil therefore has the 
composition shown in Table 8. 
Table 8 . — Composition of lumbang oil. 
Per cent. 
Linolenic glyceride 
6.56 
Linolic glyceride 
33.48 
Oleic glyceride 
56.98 
Glycerides of solid acids 
2.85 
Total 99.87 
Our experiments show that lumbang oil contains the glycerides 
of linolenic and linolic acids. Both linolenic and linolic acids and 
their glycerides absorb oxygen rapidly from the atmosphere. 
The drying power of oils such as linseed and lumbang is due to 
the glycerides of linolenic and linolic acids which these oils 
contain. In general, the more of these compounds an oil con- 
tains the quicker it dries. Our results show that lumbang oil 
has a composition quite similar to that of linseed oil and there- 
fore should be an excellent drying oil. 
In addition to ascertaining the composition we determined the 
solubility of lumbang oil in various solvents and also carried out 
a series of oxidation experiments. 
SOLUBILITY 
Lumbang oil at 28° C. is insoluble in cold ethyl and methyl 
alcohols and acetic acid. It is very soluble in cold turpentine, 
chloroform, ether, carbon tetrachloride, carbon bisulphide, pe- 
troleum ether, and acetone.' It is also soluble in ethyl acetate, 
ethylene bromide, toluene, and nitrobenzene. 
OXIDATION 
Lumbang oil, like other drying oils, has the characteristic 
property of absorbing oxygen from the air and drying to an 
elastic skin when exposed to the air in a thin layer. Brill and 
Agcaoili 18 investigated the drying properties of lumbang oil by 
spreading the oil on small glass plates and allowing it to dry 
(glass-plate method) . They found that lumbang oil compares 
very favorably with tung and linseed oils in the rate of dry- 
“ Brill, H. C., and Agcaoili, F., Philip. Journ. Sci. § A 10 (1915) 119. 
