85 



Theory. Experiment 



Carbon = 86,48 - 86,33 

 Hydrogen =11,27-11,44 

 Oxygen = 2,25 - 2,23 



These three oils, therefore, have the same hydrogen and 

 carbon, and differ only in the two latter having absorbed 

 small, but perfectly definite quantities of oxygen. 



Oil of the lavendula spica, boiling at 365° F., gave as 

 result, the formula c,' 2 h 10 o, or per cent. 



Theory. Experiment. 



Carbon = 80,35 - 79,45 

 Hydrogen = 10,90 - 11,30 

 Oxygen = 8,75 - 9,25 



The oil of peppermint had been analyzed by Blanchet 

 and Sell, who obtained results, giving the formula c 12 h,„o, 

 which has been found above for oil of lavender. As their 

 analyses were only two in number, and are given in the 

 Journal de Pharmacie without any explanatory detail, Pro- 

 fessor Kane thought it not superfluous to add to the above 

 experiments a confirmation of their results. On purifying oil 

 of peppermint of commerce, (having selected the foreign oil 

 that it might be more probably what they had examined,) 

 Professor Kane found that the more it was rectified and the 

 earlier condensed the specimens analyzed were, the more 

 the boiling point approached to 314°, and the composi- 

 tion to the formula c 5 h 4 . The difference between this 

 result and that of Blanchet and Sell is too great to be ex- 

 plained by an error in the analyses of chemists whose other 

 labours have shown such accuracy in quantitative research : 

 Professor Kane accordingly thinks it not improbable, that 

 there are two oils of peppermint of different compositions, 

 and he is now occupied in seeking amongst the commercial 

 samples for that with which the other chemists had been 

 engaged. 



