PHILIPPINE WOOD OILS. 
By A. M. CLover. 
(From the Chemical Laboratory, Bureau of Science.) 
In a study of tropical forest products there are encountered as exuda- 
tions from trees a great variety of substances, all of which may appro- 
priately be termed resins. They appear and are collected in different 
physical conditions which are modified by the rapidity with which they 
issue from the tree and the rate at which they dry or harden thereafter. 
The latter function is dependent upon the relative amounts of water, oil, 
and solids which are found in the resins and upon the chemical composi- 
tion of the oil. Accordingly, many resins are encountered in the solid 
form and contain very little volatile matter, whereas others collect upon 
the tree in a plastic condition and still others harden so slowly that they 
are removed as fluids. 
The members of the latter class which have been differentiated in a 
study of the resinous products of the Philippine Islands have shown 
among themselves a similarity in chemical composition and a likeness to 
other known products to such an extent that they may appropriately be 
placed in a class by themselves and designated as wood oils (a term 
sometimes applied to gurjun balsam). A wood oil is therefore a fluid 
resin of very slight “drying” power and containing a high percentage of 
volatile matter; the oily portion of this volatile matter sometimes is as 
much as 75 per cent of the total resin and consists entirely of bodies 
belonging to the sesquiterpene group. In no case has a low-boiling or 
terpene oil been observed in this class of products; but on the other hand 
the viscous resins nearly always contain terpenes and the relative amount 
of oil found in them-.seldom exceeds 25 per cent. 
OlL-OF SUPA. 
The tree (Sindora wallichii Benth) yielding this oil is said to be widely 
distributed over the Islands. ‘The sample examined was sent to the lab- 
oratory from the Province of 'Tayabas, where in certain localities it is 
reported to be used as an illuminant, but no information concerning its 
use in other parts of the Islands could be obtained. A freshly cut tree, 
so it is stated, yields about 10 liters of the product, to obtain which it is 
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