123 ODOROGRAPHIA, 
also reacted upon it with great energy, and a liquid was distilled 
more dense than water and possessing a piquant odour. These 
reactions showed that it was an oxygenated substance—or, rather, 
a mixture of oxygenated substances—resembling the alcohols in 
chemical properties.” Gal considers it “ probable that the acid 
referred to may be considered as forming in the oil benzoic ethers 
with these alcohols. On the one hand, the acid does not exist in 
the oil in a free state, and on the other hand he was unable to 
obtain any alcohol soluble in water by distillation of the oil in 
presence of potash.” 
An examination of the oil of Cananga was since made by Adolf 
Convert, of Frankfort, with the following result * :—“ The oil did 
not affect litmus-paper moistened with alcohol ; at 170° C.a small 
portion distilled over, but the thermometer gradually rose to 290° C., 
and at a still higher temperature the oil was decomposed. As the 
portions passing over below 290° had a strongly acid reaction, the 
presence of compound ethers was very probable. Ten grams of 
the oil were then boiled with 20 grams of alcohol and 1 gram of 
potash during one day in a flask provided with an inverted con- 
denser. ‘The alcohol was then separated by distillation, the residue 
supersaturated with dilute sulphuric acid, and, together with much 
water, submitted to distillation until the distillate almost ceased to 
have an acid reaction. The distillate was then neutralized with 
barium carbonate and the filtrate concentrated, whereupon it 
yielded crystals which were recognized as nearly pure acetate. 
The acid residue containing the potassium sulphate was shaken 
with ether, and the ethereal solution, after being evaporated, left 
a crystalline mass of an acid reaction, which was coloured violet 
by ferric chloride. This reaction, probably ascribable to the 
presence of a phenol, failed to make its appearance after the mass 
had been recrystallized from boiling water. The aqueous solution 
of the purified crystalline scales then gave only a small flesh- 
coloured precipitate with ferric chloride. The crystals, forming 
small lamelle, melted at 120°. In order to demonstrate the 
presence of benzoic acid, the crystals were boiled with water and 
oxide of silver, and the crystals that separated from the cooled 
filtrate were dried over sulphuric acid—0:0312 gram of them 
yielded, on combustion, 0°0147 gram, or 47:1 of silver. Benzoate 
* Aicuiy der Pharm. 1881, p. 218. 
