BALSAM TOLU. 263 
in benzene or carbon disulphide. Its solution in acetone is in- 
active to polarized light. 
Balsam Tolu is partly constituted of an amorphous resin which 
is insoluble in carbon disulphide, and which is apparently identical 
with the black resin precipitated from Balsam Peru by carbon 
disulphide. This resin yields by distillation a hydrocarbon which 
was termed by Berzelius Toluol, a name which is still in use on 
the Continent, but which in England has been changed into 
Toluene, C;Hgs. It is a strongly refractive liquid smelling hke 
benzene ; it boils at 110°°3, and does not solidify at —20°; oxi- 
dizing agents convert it into benzoic acid. 
Balsam Tolu contains a large quantity of cinnamic acid, which 
may be separated by boiling with water, also with carbon disul- 
phide, and identified by heating with potassium dichromate and 
sulphuric acid, when benzaldehyde will be given off in quantity. 
By distillation with water, the balsam yields one per cent. of a 
volatile oil of sp. gr. 0°945, which consists of a terpene C,)H,, 
called Tolene, boiling at about 170° C., and which rapidly absorbs 
oxygen from the air. This volatile oil of Tolu also contains com- 
pound ethers of cinnamic and benzoic acids, and is of very fine 
perfume. 
By destructive distillation, Balsam Tolu yields the same pro- 
ducts as Balsam Peru, amongst which Phenol and Styrol have 
been observed. 
This balsam does not contain either cinnamein or styracin (cin- 
namyl cinnamate), both of which are found in Balsam Peru. 
According to the researches of Kopp there are two distinct 
resins in Tolu balsam, one C;,H,,O,, and another sparingly soluble, 
C,3;H,,O;. According to Deville, however, there is only one resin, 
to which the second formula belongs. Trommsdorff obtained 
88 per cent. of resin, 12 per cent. of free acid, and only 0°2 per 
cent. of volatile oil. 
The officinal description given in the United States Dispensa- 
tory states that Balsam Tolu is “a yellowish or brownish yellow, 
semi-fluid or nearly solid mass, transparent in thin layers, and 
brittle when cold.... It is almost insoluble in water.... Warm 
carbon disulphide removes from the balsam scarcely anything but 
cinnamic and benzoic acids. On evaporating the disulphide, no 
substance having the properties of resin should be left behind.” 
It is stated that when Balsam Tolu is dissolved in the smallest 
