— 118 — 



former V 2 h. and 1 h. saponifications), and that an addition of only 2% 

 produces a difference of 6,4; consequently even small sophistications of this 

 nature should now be readily traceable. 



A remarkable fact is that when up to about 10°/o terpinyl acetate is 

 added the ester value of the diluted sample is only slightly increased, 

 the true linalyl acetate content being thus ascertainable with approximate 

 exactitude. 



In connection with the above we give the analytical values of a few 

 samples of adulterated bergamot oil which have been submitted to us 

 for our opinion: — 



d 15 o 0,8955 0,8827 0,8843 



«d +16°10' + 9°0' +19°25' 



Evaporation-residue 4,2% 4,8 % 6,8 % 



Sap. v. of evap. residue .... 180,0 186,6 178,7 



Solubility in 90°/o alcohol . . . 0,3 v. a.m. 0,3 v. a.m. 0,3 v. a.m. 



Acid v 1,8 1,6 4,1 



Ester v. after 1 hour's saponif. 



with lOcc. seminormal potash 104,2 96,4 97,4 

 Ester-content (calc. as linalyl 



acetate) 36,5 °/o 33,7 % 34,1 °/o 



Ester v. after 2 hours' saponif. 



with 20 cc. seminormal potash 121,8 105,6 101,3 

 Ester v. after 1 hour's saponif. 



with 10 cc. seminormal potash 



+ 25 cc. alcohol 88,2 86,6 92,1 



Difference 33,6 19,0 9,2 



Sap. v 106,0 98,0 101,5 



Acid v. II 102,3 88,7 92,0 



Difference 3,7 9,3 9,5 



Terpinyl acetate content. . . . about 20% about 10% about 4% 



Esters of sparingly volatile acids ) L . - 

 ^. , \ s J \ not found. 



Glycerol esters ] 



The dilute saponification indicates a content of linalyl acetate 



below 30,9% about 30,3% about 32,2% 

 instead of above 36,5% 33,7% 34,1% 



While on this subject we may refer to a notice by Jeancard and Satie 1 ) 

 on the estimation of citric esters and glycerol esters in essential oils. 

 These authors isolate the citric acid from the saponified oil by a suitable 

 method and detect the crystals by means of the microscope. The glycerol 

 they convert into acroleine with acid sulphate of potash. 



*) Rev. gen. de Chim. 14 (1911), 177. 



