WINTEEGREEX. 337 



similar precipitate was formed, but in smaller quantity upon 

 decomposing the soap from peach kernel and other similar oils, but 

 not from the soap of artificial bitter almond oil. 



The gravimetric method of assay was conducted as follows : — 

 A small, convenient quantity (1"5 to 2 grammes) was weighed in 

 a tared flask of 50 c. c. m. capacity, a slight known excess of a 

 strong solution of caustic soda added, the flask securely corked and 

 the contents rotated over a moderate heat until the disappearance 

 of the precipitate formed by the soda solution. After cooling, 

 the cork was removed, and the litpiid again subjected to heat for 

 five minutes, this time at the boiling point, after which it was 

 transferred to a separating funnel, where it was treated with a 

 slight excess of hydrochloric acid, and the precipitated salicylic 

 acid taken up by shaking the resulting mixture with two 

 volumes of ether. After subsidence, the aqueous stratum was 

 drawn off into a second separator and shaken with two volumes of 

 ether ; again drawn off" into a third separator and shaken with two 

 volumes of ether: when, upon resting, the aqueous solution was finally 

 drawn off, found to be free from salicylic acid, and rejected. 

 The ethereal solutions in the separators were then washed in 

 succession four times, each time with two volumes of distilled 

 water, to free them from sodium chloride. That in the first 

 separator was transferred to a tared platinum dish, as was that 

 in the second, after passing through the first, and that in the 

 third after passing through the second, and thence also through 

 the first. The ethereal liquids were carefully evaporated and 

 the residue dried over sulphuric acid to a constant weight.* 



Ethyl salicylate can be obtained by distilling a mixture of 2 

 parts of absolute alcohol, Ih part of pure salicylic acid and 1 part 

 of sulphuric acid. The first product consists almost entirely of 

 alcohol, a mixture of alcohol and salicylic acid then passes over^ 

 and lastly the bulk of the ethyl salicylate formed. The distillation 

 must be stopped when a disengagement of sulphurous acid is 

 observed. The product is washed with water rendered slightly 

 ammoniacal, then dried over calcium chloride and rectified. Ethyl 

 salicylate is a colourless, fragrant liquid of sp. gr. 1-1345 at 15^ C, 

 boiling at 231^ to 232'^'5. It is but very slightly soluble in water, 

 but in combination with potash or soda forms crystalline 

 compounds which are soluble in water. 



* British and Colonial Druggist, 9tli Sept., 1892, p. 2S0. 

 Y 



