LAVENDER. 



427 



Ester percentages of other lavender oils from various sources 

 were found to be as follows : — 30 per cent., 36 per cent, (in two 

 cases), 33*8 per cent., 34*2 per cent., 39 per cent., 32-8 per cent., 

 30'7 per cent., and 31*5 per cent. (Pure oil from the dried flowers 

 gave 22-2 per cent.). It follows therefore that 30-33 per cent, 

 may be taken as a fair standard percentage for a good sample of 

 lavender oil. 



In order to find out whether tlie ester-determination is reliable 

 in the presence of large quantities of Turpentine oil, mixtures were 

 made of the latter oil with a lavender oil testing 32-33 per cent, 

 of linalool-acetate and the ester percentage of the mixture then 

 determined, the result being as follows : — 



Messrs. Schimmel & Co. state that experiments for the quanti- 

 tative determination of free linalool in lavender oil have not yet 

 attained the desired result, Ijut in their investigations they have 

 made use of the relatively favourable affinity of linalool for 

 acetic-anhydride, with which it combines to form linalool-acetate. 

 In these experiments, made with mixtures of linalool-acetate and 

 linalool and terpene (limonene), 10 c. c. m. of the mixture were 

 boiled with acetic anhydride and sodium acetate in a reflux 

 stoppered glass retort, and the mass, after cooling, warmed with 

 three times its volume of water and shaken in order to decompose 

 the excess of the anhydride. After washing out with water and 

 with baryta- water, the ester percentage of the dry neutral product 

 was determined by saponification. 



