— 151 — 



moistened filter was evaporated on the water bath to a small volume 

 and afterwards distilled in vacuo. By this method we obtained from N^-3 

 sample about 7 grams and from No. 3 sample about 50 grams ester, 

 possessing the following constants: — 



No. 2 No. 3 



B. p. (5 mm.) ... 128 to 135° 127 to 132° 



d 15C 1,1753 1,1835 



Acid v. . .-. ... 4,2 0,6 



Ester v 541,8 577,7 



miscible with water. 



Of the ester from No. 3 oil a sufficient quantity was available to 

 permit of its being broken up into its constituent parts. For this purpose 

 40 g. was saponified with the calculated quantity of sodium hydroxide 

 in a concentrated aqueous solution; the solution was then distilled, and, 

 as only water passed over, it was next evaporated to dryness in a dish. 

 The attempt to separate the alcohol which had been split off from the 

 ester from the sodium salt of the acid by means of an extracting agent 

 was a failure, because the known solvents took up not only the alcohol 

 but also considerable quantities of the sodium salt. To remove this 

 trouble, the sodium salt was decomposed with the calculated quantity of 

 dilute sulphuric acid and the organic acid which was liberated removed 

 by distillation, and subsequently by evaporation. This acid was identified 

 as acetic acid. It was now easy to separate the alcohol of the ester 

 from the residual sodium sulphate by means of ethyl alcohol. When the 

 ethyl alcohol had been evaporated by distilling in vacuo, the ester alcohol 

 was identified as glycerol by its b. p. 147° (4 mm.). 



The adulterant had now been proved to be a glyceryl acetate. Judging 

 from the high figure of the saponification value it consisted of a mixture 

 of glyceryl monoacetate and glyceryl diacetate. Comparison of the ester 

 content of the three oils before and after extraction shows that the adul- 

 teration had the effect of falsely representing the oils to contain the follow- 

 ing percentage of linalyl acetate in excess of the true content: 

 No. 1 4,5 °/o, No. 2 l,2°/o, No. 3 10,7°/o. 



1 g. ester roughly corresponds to 2 g. linalyl acetate. The following 

 quantities are calculated for the pure glyceryl esters: 



1 g. glyceryl monoacetate = 1,46 g. linalyl acetate 

 1 g. glyceryl diacetate «= 2,23 g. „ 

 1 g. glyceryl triacetate = 2,70 g. „ 



Ernest J. Parry 1 ) who has published the analytical values of several 

 samples of bergamot oil tested by him according to the proposed method, 



2 ) Perfum. and Essent. Oil Record 2 (1911), 14. 



