The Oils of Spearmint and Lavender. 445 



The oil examined by Mr. Brande, and which probably con- 

 tained much stearopten, was found by him of a specific gra- 

 vity 0-9206. In the specimen which I tried the specific gra- 

 vity was 0-9 1 74. By repeated rectifications, by which as much 

 of the solid matter as possible was separated, it was obtained 

 0-8865, and then boiled at 370° Fahr. Another portion 

 equally rectified had a specific gravity 0*8745, and boiled at 

 365° Fahr. Saussure, who likewise examined this oil, states 

 its specific gravity, when pure, to be 0*877. 



A specimen of the commercial oil, the specific gravity of 

 which was 0*9172, was rectified, and the product received in 

 four different vessels, stopping when the residue in the retort 

 appeared to become thick. 



No. 1 had sp. gr. = 0-88M~l ^,i ^^^^ ^^^^^^^ ^^^^ 



3 = 0-8884J ""^"^ ^^^ ' 



4 = 0-9050 boiled at 390°. 



The residue solidified by cooling. The difficulty of pro- 

 nouncing on the absolute purity of any one portion of oil of 

 lavender is thus evident. 



The analysis of this oil was conducted in the usual way. 

 Different portions of oil were selected, in consequence of 

 their boiling points and specific gravities not being in ac- 

 cordance. 



A. Specimen sp. gr. = 0*8865 ; boiling point = 370° F. 



Material = 0-4333 gramme gave 

 Water = 0-441 



Carbonic acid = 1-245 



B. Specimen sp. gr. = 0*8745 ; boiling point 365°. 



Material = 0-2835 gramme gave 

 Water = 0-299 



Carbonic acid = 0-819 



C. Specimen sp. gr. = 0-8864 ; boils at from 365° to 370°. 



Material = 0-3788 gramme gave 

 Water = 0-394 



Carbonic acid = 1*079 

 Hence the composition 



A. 

 Carbon = 79*45 

 Hydrogen = 11-30 

 Oxygen = 9*25 



As it is quite evident that, the heavier this oil is, the more 

 stearopten it contains, and consequently, the less pure it is ; 

 and as, by Dumas's analysis, stearopten, if not completely 

 identical, has at least the same composition with common 



