EUCALYPTUS OIL CONTAINING GERANYL ACETATE. 143 



presence of aromatic alcohols has often, been detected; either free 

 or combined as esters, and in a paper before this Society 1 it was 

 shown that in the oil of E. patentinervis, either geraniol or linalol 

 was present as free alcohol ; from the results of this research it 

 was probably geraniol. 



The species of Eucalyptus now being described, the oil of which 

 contains such a large percentage of geraniol, is known locally as 

 'Paddy's River Box'; its botanical name is Eucalyptus macarthuri. 

 It grows plentifully in the Wingello district of this colony, on the 

 banks of Paddy's River it is found as a fine foliaceous tree. The 

 oil obtained from this species has no resemblance to ordinary 

 Eucalyptus oil, and belongs to none of the well defined chemical 

 groups of these oils. It thus becomes still more difficult to define 

 in a simple sentence what Eucalyptus oil really is. 



The crude oil of E. macarthuri, obtained by steam distillation 

 from fresh material of leaves and terminal branchlets, is reddish 

 in colour owing to the presence of a small amount of free acid in 

 the original oil. In appearance, odour, etc., it resembles more 

 than anything else, the crude oil of Darwinia fascicularis, but 

 the higher boiling portion consists largely of eudesmol, the stear- 

 optene of Eucalyptus oil, which constituent is absent in Darwinia. 

 Although containing this stearoptene no crystals we're obtained 

 when the crude oil was placed in a freezing mixture, eudesmol 

 being so exceedingly soluble in the oil. 



The free acid present could not be determined in the usual way 

 because it was found during the research on the oil of Darwinia 

 fascicularis, that saponification of geranyl acetate takes place 

 readily in the cold, if alcoholic potash be used. Full description 

 of the rates of saponification is given in the paper referred to. 

 The free acid was readily removed from the oil of E. macarthuri, 

 by agitating with a very dilute aqueous solution of potash, the 

 ester not being saponified by this treatment; the oil was after- 

 wards well washed and dried. Saponification of the oil before 



1 Proc. Eoy Soc, N. S. Wales, 1900, p. 74. 



