ESSENTIAL OIL FROM BARK OF EUCALYPTUS MACARTHURI. 177 



ON THE ESSENTIAL OIL FROM THE BARK OF 

 EUCALYPTUS MACARTHURI. 



By Henry G. Smith, f.c.s. 



[Read before the Royal Society of N. 8. Wales, October 4, 1916.~] 



It has been generally known to distillers, who have ex- 

 tracted the essential oil from the leaves of this Eucalyptus, 

 that the bark is particularly odoriferous. The leaf oil is 

 very rich in geranyl-acetate and appears never to contain 

 less than 60 per cent, of that constituent, while a consider- 

 able amount of free geraniol is present also. 



The first analysis of the oil of this species will be found 

 in the Journal of this Society, November 1900. Since that 

 time numerous analyses have been made with the oil dis- 

 tilled at various times of the year, and these have all been 

 in agreement with the one first published. 



Quite recently a considerable demand has arisen in 

 Australia for perfumery oils from indigenous trees, and 

 consequently a good deal of oil has been distilled from the 

 leaves of E. Macarthuri, the product being one of the best 

 geraniol bearing oils obtainable from Australian plants. 



It was found that an essential oil could also be distilled 

 commercially from the bark of this species, and it was thus 

 considered desirable that the composition and quality of 

 this bark oil should be determined prior to it being placed 

 on the market. 



The Technological Museum is indebted to Mr. J. Quigg 

 of Wingello in this State, who kindly forwarded the freshly 

 stripped bark for the purpose of distillation. It had been 

 obtained from fair sized trees, and ranged in thickness up 

 to \\ inches. The odour of geranyl-acetate was distinctly 



L— October 4, 1916. 



