Dr. Kane on the Composition of certain Essential Oils. 139 



III. OIL OF PEPPERMINT. 



This oil had been submitted to analysis by Blanchet and Sell,* but their results 

 having been communicated without any detail, and the analyses being exceedingly 

 discordant, I was obliged to reexamine its constitution before I could satisfy my 

 mind. The result has been, that I have obtained a formula differing from that 

 of the chemists before named. 



The oil of peppermint of commerce, particularly that sold as American, is 

 often adulterated by a large quantity of oil of turpentine, from which, if once 

 mixed, no number of rectifications can completely purify it. The rough oil, 

 when pure, has, according toBrande, a specific gravity 0.907; I found it 0.9083. 

 It contains a certain quantity of stearopten, though not so much as the gene- 

 rality of oils ; when freed from this by repeated distillations it has a specific 

 gravity of 0.8998, and bolls between 370° and 380° Fahr. 



The following are the analytical results : 



A. Material =: 0.2905 gramme gave 



Water = 0.318 



Carbonic acid = 0.812 



B. Material = 0.3667 gramme gave 



Water = 0.407 



Carbonic acid = 1.035 



C. Material = 0.3443 gramme gave 



Water = 0.375 



Carbonic acid ■=z 0.969 

 Hence there is per cent. 



A. B. C. 



Carbon = 77.29 78.06 77.81 



Hydrogen = 12.11 12.32 12.01 



Oxygen = 10.60 9-62 10.18 



The analyses A and B were made with the same specimen of oil ; the correct 

 value for carbon is therefore that of B. The analysis C was made subsequently 

 with a different specimen. 



• Journal de Phartnacie, vol. xx. 1834. 



