200 
chemical study and the few superficial examinations which have been 
made and recorded do not show much agreement, other than that the 
volatile oil boils within a narrow range of temperature at about 255°. 
The balsam is used in India for preparing varnishes and in adulterating 
essential oils. It is often stated to be sufficiently mobile to permit of 
filtration, to possess a fluorescence, and to coagulate on heating. A sample 
of this product purchased from a drug firm in Manila was found to 
contain 74 per cent of volatile oil capable of being removed by direct 
distillation. Only a trace of water was present and the residue was 
viscous. 
The violatile oil redistilled within 2° (154° to 156° at 48 millimeters) and 
showed the following constants: Rotation, +53° (10 centimeters, 30°). Specific 
ravity, {——)} = 0.9103. 
gravity, (33) 
This gurjun balsam was completely soluble in all the ordinary solvents 
excepting ligroin, in which it showed a decided turbidity, differing in 
this respect from the sample of copaiba balsam and also from Oil of Supa; 
it is also distinct from each of these products in the composition of its 
volatile oil, as is indicated by the boiling point. Gurjun, as well as 
copaiba, is produced by making a deep cut, or cavity, in the trunk of the 
tree near the base. Into this the resin exudes rapidly, amounting in 
individual instances to from 50 to 180 liters. After the exudation has 
diminished, a fire is built in the cavity or on the ground below it, which 
means greatly increases the flow. 
From such a general knowledge of the balsams of copaiba and gurjun 
as it is possible to obtain, it appears that Oil of Supa is a very similar 
product and that it should prove valuable for the same uses. Copaiba 
and gurjan, as well as the oil distilled from them, are used for like 
purposes in medicine. Considering that these oils are not identical and 
possibly have nothing in common, except that they belong to the class 
of sesquiterpenes, it seems very probable that the volatile oil from Supa 
could be put to the same uses. The Oil of Supa could also be utilized 
in the ways mentioned, namely, in making varnishes, paints, and trans- 
parent paper, and in the adulteration of other oils. 
In connection with these products the resin from the Dipterocarpus 
tree, Mayapis (Tagalog), is of interest. This product is considered by 
Dr. Tavera in his book “Medicinal Plants of the Philippines” to be iden- 
tical with gurjun balsam. A sample of the resin from Mayapis was 
obtained from Bataan Province. On examination it proved to be quite 
similar to the two Dipterocarpus wood oils which have already been 
considered. It contained 15 per cent of water and 25 per cent of sesqui- 
terpene oil, which could be removed by careful distillation sbi 
decomposition. The residue was quite hard. 
‘Wiesner: Die Rohstoffe des Pflanzenreiches. 
