459 



a For Pharmaceutical Purposes. The species from which the firsl sample 

 mi Eucalyptus oil had been distilled was /•.'. pipei ita, and this Eucalypl givi - a pro- 

 duct consisting oi phellandrene, piperitone, i ineol and some minor constituents 



It is worthy oi mention thai the Eucalyptus oil industry was established 



in Australia on oils oi tins (lass. It was in 1853 that Huron von Mueller 

 recommended the distillation oi Eucalyptus oil, ami he claims this in his "Extra 

 Tropical Plants," under E. amygdalina. In 1854 Mr. J. Bosisto established, in 

 Victoria, the first factory for the commercial distillation oi Eucalyptus oil 



in Australia, the species utilised being chiefly the one known at that time as 

 E. amygdalina. The oil oi that species contained phellandrene, piperitone and 

 cineol, and in constitution had some resemblance to thai oi E. piperita. 



As the more pronounced cineol bearing Eucalyptus oils became in 

 request, those containing phellardre.no receded in favour, and to meet this 

 demand the " Malice " oils came into prominence, while in Tasmania the chief 

 species employed was E. globulus. The " Mallee " oils, being as a rule more 

 closely related to the " Boxes," have, in most cases, distinctive properties from 

 those of the E. globulus type, in that the}' contain the aldehyde aromadendral, a 

 constituent which has been shown by Dr. Cuthbert Hall and others to have five 

 or six times the bactericidal value of cineol. 



The demand at present for medicinal oils is mostly for those having a high 

 cineol content, and the United States Pharmacopoeia demands a minimum of 

 70 per cent, of that constituent ; but, as can be seen from the results recorded in 

 this work, only a comparatively few species vield oils of this character in 

 fufficient amount to be profitable for distilling at the usual price paid for cineol 

 oils, and for that reason the demand for those containing 70 to 80 per cent, 

 of cineol has, for some time past, far exceeded the supply.* 



The British Pharmacopoeia's standard is more reasonable, only requiring 

 55 per cent, of cineol. For the supply of oils of this qualitv Australia has 

 numerous species, as can be seen by referring to the lists under Group 111, 

 class (6), and group IV, class (a). 



The question, however, is not yet settled as to whether cineol is the most 

 valuable medicinal constituent in Eucalyptus oils, and Dr. Attfield directs 

 attention to this uncertainty in his work on Chemistry (p. 505). Mr. E. M. 

 Holmes (Pharm. Journ. Ill, 25, p. 501 : says that " the chemistry is far in 

 advance of the therapeutic and physiological knowledge of Eucalyptus oils." 



In connection with this question an investigation on the bactericidal value 

 of the several constituents of Eucalyptus oils was undertaken by Dr. Cuthberl 

 Hall, of Parramatta, in 1904; these results were published privately. 



Considerations respecting the therapeutic value of Eucalyptus oils are 

 beyond the scope of this work, but much information may be found scattered 

 throughout the various scientific and pharmaceutical publications. 



Such a large number of constituents occur in oils of the various Eu< alypts, 

 that it may be the medicinal value of Eucalyptus oil is more largely due to the 

 admixture of certain of these, than to that oi any one individual constituent. 



b For Mineral Separation. As with cineol, other constituents which 

 contain oxygen, such as citronellal, piperitone, aromadendral, geranyl-acetate, 

 &c, as well as the several terpenes, reach a maximum in the oils oi particular 

 specie? of their class, and by taking advantage of this peculiarity, and exploiting 

 those species which contain the desired constituent in greatest abundance, these 

 products are now, or may eventually become, articles of commerce. 



• Commercially pure cineol is now manufactured in Vnstralia, ami can U: siippln-.i m n 



desired to use the pure producl in prefe to 11 Is. 



