- 6 7 - 



content. This ester is almost odourless, so that the scent is not 

 affected, and in spite of the high density, an addition up to 5 °/ will 

 scarcely be revealed by too high a specific gravity in the case of 

 light lavender and bergamot oils; on the other hand, this small 

 quantity suffices to give an apparent increase in the content of linalyl 

 acetate of about io°/ , owing to the tri-basic character of the citric 

 acid ester. This shows how dangerous an adulterant this triethyl 

 citrate is. Bennett quotes the following constants for it: b. p. 285 

 to 295 ; d 15 o 1,146; «d +o°; n D20° JJ4400; sap. no. 610. For the 

 detection of the ester it is advisable to distil off at reduced pressure 

 the bulk of the oil in question, then to saponify with aqueous potash 

 liquor the residue which contains the high -boiling artificial ester, 

 and finally to fractionate the whole saponification liquor in order to 

 detect the ethyl alcohol. The citric acid is then left behind in the 

 residue, and can be weighed as barium salt, which Bennett prefers 

 to the silver salt which decomposes violently when heated. 



The above communication induced us also to study the adulterations 

 with citric acid ester. For this purpose we produced an ester of the 

 following constants, which correspond almost completely with those 

 given by Bennett: d^o 1,1422, n D2o° i>447i> sap. no. 615,0, b. p. 

 165 (7 mm. pressure) and 144 to 145 (3Y2 mm - pressure). We 

 added this ester to lavender oils, and found that additions of even 

 2 °/ ethyl citrate can be detected with certainty. We propose the 

 following trial test, to determine in doubtful cases whether or not 

 it is an adulteration with citric acid ester. About 3 grams of the 

 suspected oil are saponified with alcoholic potash liquor, the liquid 

 neutralised with hydrochloric acid, and evaporated to dryness on the 

 water bath. The residue is dissolved in water, then extracted with 

 ether in order to remove the last traces of oil and resin, and filtered. 

 The solution cleared in this manner is mixed with a concentrated 

 solution of calcium chloride, and heated. If citric acid is present, a 

 white precipitate of calcium citrate occurs, which on cooling dis- 

 appears again. 



Lemongrass Oil 1 ). Our fears that the Indian producers, in view 

 of the profitable prices of the last harvests, would be tempted to 

 extend their plantations excessively, have unfortunately come true, 

 and it will now probably be difficult to lift this article again to a 

 sensible price basis. Whilst the total shipments during the season 

 (July I st to June 30 th ) of 1904/5 amounted to i88iY 2 cases, and 

 1905/6 to 2 26g 5 / 12 cases, the export during the months July to 

 December 1906 already amounted to 3603 1 / B cases, that is to say 

 nearly as much as in the previous two whole years together. It is no 



*) Comp. also under Palmarosa oil, p. 57. 



