i66 



On rectification, 2 per cent, distilled below 165 C. (corr.). This portion 

 consisted largely of volatile aldehydes with some acid water. Between 165-183, 

 87 per cent, distilled; between 183-260, 4 per cent, came over, and between 

 260-270, 2 per cent, distilled. These fractions gave the following results : 

 First fraction, sp. gr. at 15 C. == 0-9094; rotation a D + 8-7. 

 Second ,, ,, = 0-9241 ; rotation not taken. 



Third ,, ,, = 0-9430; rotation 



The cineol, determined by the phosphoric acid method in the first fraction 

 and calculated for crude oil, was 57 per cent. (O.M.) By the rapid phosphoric 

 acid method, determined in February, 1920, the result was 64 per cent. 



It will be seen from these results that the oil we "distilled from E. globulus, 

 growing naturally in New South Wales, was similar in character and constituents 

 to those always obtained with the oil of this species, no matter where the trees are 

 found growing naturally. This comparative constancy in the chemical product of 

 identical species of Eucalyptus is one of the most interesting results brought to 

 light by this research. This constancy in constituents is not peculiar to the oil of 

 E. globulus alone, but is common to the several members ot the genus, and 

 innumerable instances of this fact are recorded in this work. It has been, we 

 think, this constancy of constituents that enabled the oil of E. globulus originally 

 to command such favourable consideration from those dealing in Eucalyptus oils. 

 It is an "illustration of the advisability of restricting operations to species the oils 

 of which are in most request, and of keeping the product of individual species 

 distinct. If this be done, then the quality of any Eucalyptus oil can be assured, 

 and the industry become of greater importance, the species name being 

 a guarantee of the constancy of the product ; the purchaser could then 

 be sure of obtaining what is required. That this method is a judicious 

 one has been illustrated over and over again, more particularly, perhaps, with the 

 oils of E. Macarthuri, E. polybractea, and E. Australiana. Nothing can be more 

 detrimental than the indiscriminate mixing of oils of the various Eucalypts, 

 and if more than one species belonging to the same chemical group are being 

 worked, it would even then be better to keep the products distinct, although the 

 oils may be in agreement. The advantages to be derived from such a procedure 

 will be more fully recognised when cultivation of Eucalyptus species for their oil 

 products shall become more general. Eucalyptus globulus belongs to a group 

 of cineol-pinene oil yielding trees, of which many occur in Australia, the oils of 

 which are often not easily distinguishable from each other. Commercially- 

 distilled Eucalyptus oils ought, therefore, to be supplied with that constancy of 

 constituents and physical characters which have so long been characteristic 

 of the product of E. globulus. Very little oil of this species is now distilled in 

 Australia, as the products of more prolific yielding species have supplanted it, 

 the higher yields of oil of these species alone being answerable for this. 



