LAVENDER. 367 
various writers have affirmed that it contains in solution a 
stereoptene identical with camphor, but whether recently distilled 
oil contains it, is doubtful. Its sp. gr. is variable between 0°876 
and 0°880 at 15° C. It is completely soluble in three volumes of 
alcohol of 0°894. 
The principal adulterants are French oils of LZ. vera and L. spica, 
oil of turpentine, and alcohol. 
The presence of French oils is recognized by the keen sense of 
smell possessed by accustomed buyers. The sp. gr. of pure French 
oils of ZL. vera varies from 0°885 to 0°887. The commercial 
French oils are very frequently adulterated with turpentine, which 
has a sp. gr. ranging from 0°856 to 0°870. 
Oils containing turpentine and pure French oils of sp. gr. over 
0°890 are less soluble in a given volume of alcohol of a given 
strength than are pure English oil and pure French oils of sp. gr. 
0°885 to 0°889. 
Dragendorff found * that 1 c. c. of oil of lavender (prepared by 
himself) dissolved in 2°3 c. c. of 65 per cent. alcohol (according to 
Tralle’s aleoholometer, which gives the percentage volume for the 
temperature of 60° F.), the observation being made at a tempe- 
rature between 15° and 20° C. He also found that on experi- 
menting with ten different kinds of oil of turpentine, most of them 
required 3°5 to 3°75 of 92 per cent. alcohol to dissolve 1 ¢. c., and 
that 1 c. c. of a mixture composed of 10 parts oil of turpentine 
and 90 parts oil of lavender did not form quite a clear mixture 
with 5 c. ec. of 65 per cent. alcohol. 
On these figures it would be natural to expect that some reliance 
could be placed on a test which has been frequently given, viz. 
the solubility of 1 part of lavender oil in 3 parts of 70 volumes 
per cent. alcohol at 16° C.; but some recent investigations tend to 
show that pure oils may be brought under suspicion by this test, 
and that actual adulteration with 20 per cent. of turpentine is not 
detected by it +. It would therefore be well if distillers who have 
yet on hand some stock of their own make (in which of course 
they can rely for purity) to repeat the experiments. 
The optical rotation of pure Mitcham oil has been recorded as 
— 4° 2'in a column of 50 mm. and that of French oils —4° 15’ to 
* Neues Repert. fiir Pharm. xxii. i.; and Pharm. Journ. [5] vi. p. 541. 
+ Schimmel & Co., § Bericht,’ Oct. 1890. 
