430 ODOKOGKAPIITA. 



These examples prove tliat Lavender oil contains a large per- 

 centage of free linalool. 



The ester-determination constitutes a distinct advance in the 

 methods of examination of lavender oil, and it should always be 

 carried out in addition to the determination of the specific gravity 

 and the optical rotation. 



Spike oil, which is also a common adulterant of lavender oil, 

 contains about oO per cent, of an alcoholic body, but only small 

 (quantities of ester. Hence the addition of Spike oil to lavender 

 oil decreases considerably the ester percentage of the latter. The 

 surest method of detecting the presence of Spike oil is to test the 

 suspected sample for the presence of Cineol, which is a 

 constituent of Spike oil, but does not occur in lavender oil. 



Messrs. S. & Co. further remark that they have convinced 

 themselves that all samples of Lavender oil of unimpeachable 

 excellence are soluble in three times tlieir v(»lume of 70 per cent, 

 alcohol. 



The formation of linalyl-acetate has been studied by Bouchardat,* 

 who states that acetic anhydride reacts with linalool at the 

 ordinary temperature, and appears to cause the formation of the 

 corresponding ether, from which the linalool may be regenerated, 

 but the reaction is slow and incomplete. As soon, however, as the 

 temperature is raised and maintained for some time at 100 '^ to 120^, 

 combination takes place, and the rotatory po^ver disappears, but at 

 the same time an acetic ether is formed, which is a derivative of 

 another alcohol. This ether has a density of 0'9o77 to 0*9467 at 

 0^, and possesses a very agreeable odour, recalling that found in 

 the oil of Lavandula cera. Saponified with alcoholic ])Otash at 

 100^ a neutral compound, C^^, H^^ O.^, is formed, which boils at 

 226"^ to 231^ with slight decomposition, is totally inactive when 

 polarised, and has a density of 0-9061 at O*-^. It combines with 

 four equivalents of bromine, which it decolorises instantly like 

 linalool, a Ijody l^eing formed which is crystalline or oily, according 

 to the temperature employed. The alcohol has an 

 Geranium agreeable rose odour, and has been proved to be 



(p. 44). identical with geraniol, the chief ingredient of all 



geranium oils, and which is isomeric with linalool 



and closely allied to oleginic alcohol. The various geranium oils 



also contain, in addition, other constituents at present unknown. 



* Comptes Eendus, cxvi., p. 1253. 



