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



100 



I cannot explain the diflPerence between this result and that of Blanchet 

 and Sell, as they give no account of the circumstances under which their 

 analyses were made. They make no mention of having submitted their oil to 

 rectification. Their result is c,2 Hm o, and per cent. 



Experiments. Theory. 



Carbon = 79-63 79-53 80.35 



Hydrogen = 11.25 10.77 10.90 ■ 100 



Oxygen = 9-12 9-70 8.75 . 



Blanchet's result for the stearopten of oil of peppermint, though discordant 

 with itself, yet approaches closer to mine for the oil. Thus he obtained for the 

 solid crystalline stearopten Cm Hk, o, and per cent. 



Experiments. Mean. Theory. 



Carbon = 79.63 77.27 78.45 77-28 " 



Hydrogen = 11.25 12.96 12.11 12.59 ■ 100 



Oxygen = 9-12 9-77 9-44 10.12 . 



On analyzing the first portion obtained in rectifying oil of peppermint, which 

 had a boiling point about ten degrees lower than the general mass subsequently 

 condensed, I obtained the following result : 

 Material = 0.337 gramme gave 



Water = 0.360 



Carbonic acid = 0.969 



Hence per cent. 



Carbon = 79-53 



Hydrogen = 11.86 



Oxygen = 8.61 

 This result might be considered as approximating to that of Blanchet ; but 

 this portion could not be considered as being pure oil, as it constituted not a 

 tenth of the quantity submitted to distillation. I attributed its different compo- 

 sition to an adulteration by oil of turpentine, which from its greater volatility 

 came over in the commencement. If the oil of turpentine were in large quan- 

 tity, a complete rectification could not be obtained. 



