86 H. G. SMITH. 



On the CRYSTALLINE CAMPHOR of EUCALYPTUS 

 OIL (EUDESMOL), and the NATURAL FORMATION 



of EUCALYPTOL. 

 By Henry G. Smith, f.c.s., Technological Museum, Sydney. 



[Bead before the Royal Society of N. 8. Wales, August 2, 1899.'] 



In August 1897, a paper was read before this Society by Mr. R. T. 

 Baker and myself, 1 in which was announced a crystalline camphor 

 or stearoptene isolated by us from the oil of Eucalyptus piperita. 

 The specimens then shown only consisted of a few isolated crystals 

 as the camphor does not appear to exist in quantity in the oil of 

 this species. At that time no investigation could be undertaken 

 to determine its constitution, it being obtainable in such minute 

 quantities, but it was thought that it must be a constant con- 

 stituent in these oils, and that it might be obtainable from other 

 species of Eucalypts in larger quantity. 



This surmise was correct, as the camphor has been found to be 

 present in the oils of several species of Eucalyptus, and as will be 

 presently shown, should be isolated, at certain times of the year, 

 from the oils of all those species of Eucalypts whose ultimate con- 

 stituent is eucalyptol. The results so far obtained in reference to 

 this camphor may assist somewhat towards a more complete 

 knowledge of the chemistry of Eucalyptus oils, and help to explain 

 the differences, found at certain times of the year, in the con- 

 stituents of the oils of this genus. The differences found existing 

 in the several members, apparently made a correct expression of 

 opinion in reference to them exceedingly difficult, but as our 

 knowledge increases these difficulties partly disappear, and the 

 explanations that can now be given considerably simplify the 

 study of these trees. In the determination of the chemical con- 

 stituents of the several species of Eucalypts, we have a check 



l On the Essential oil and the presence of a solid camphor or stearoptene 

 in the " Sydney Peppermint " Eucalyptus piperita. 



