236 



The Philippine Journal of Science 



Lumbang banucalag (Aleurites trisperma) is confined to the 

 Philippine Islands. Though of wide geographic distribution in 

 the Archipelago, extending from central Luzon to Mindanao, it 

 is less common and much more local than is lumbang bato. The 

 oil is darker colored and more viscous than lumbang bato oil. It 

 is commonly supposed to cause skin eruptions on contact, but I 

 have seen no foundation for this belief. I have handled the oil 

 constantly in this work, but have suffered no inconvenience. 

 The yield, calculated on the kernel weight, is about 43 per cent by 

 hydraulic expression at 310 kilograms per square centimeter. 



Brill and Agcaoili 5 found that the lumbang oils are comparable 

 with linseed oil in drying quality of film and percentage change 

 in weight when drying ; also that they can be used as substitutes 

 for tung, or Chinese wood, oil, the product of allied species of 

 the same genus, Aleurites fordii and Aleurites cor data. 



EXPERIMENTAL PART 



The oils used in this series of tests have the constants noted in 

 Table I. 



Table I. — Oil constants. 1 







Fresh lumbang:. 



seed oil. 



Bato. 



Banucalag:. 



0.9368 

 197. 74 

 145.25 



8.70 





0. 9345 

 189.40 

 183.96 



0.50 



0.9252 

 192.95 

 150.36 



1.05 











" Analyzed by F. Agcaoili, chemist, Bureau of Science. 



All the tests included in this preliminary work have been 

 carried on under ordinary Philippine laboratory conditions, that 

 is to say, in diffused daylight, at a temperature of from 28° to 

 30° C, and at a relative humidity of about 75 per cent. 



Drying test. — The drying tests were made in the usual way 

 by spreading a small amount of oil to uniform thickness on 

 glass plates, each 6.35 by 8.89 centimeters (2.5 by 3.5 inches) 

 in size. The oil films were placed in a glass case and were 

 exposed to a dry atmosphere obtained by passing a slow current 

 of air through sulphuric acid. The changes in weight and ap- 

 pearance are shown in Table II and in fig. 1. 



6 Op. cit. 



