116 R. T. BAKER AND H. G. SMITH. 



The Eudesmol. 

 This new stearoptene, eudesmol, was first found in the oil of 

 Eucalyptus piperita floe. cit. J. It exists in large quantity in the 

 oil of Eucalyptus macrorhyncha and may be obtained in abundance. 

 Three methods have been successfully employed in obtaining it : 

 (1) It may be obtained from the oil distilled about November (when 

 it appears to be present in the greatest quantity) by placing the 

 oil in shallow vessels and allowing the volatile constituents to 

 evaporate, eudesmol then crystallises into a solid mass after a few 

 days. The March distillate did not succeed so well in this respect, 

 but it is a very wasteful method and not to be thought of practic- 

 ally. (2) The oil may be redistilled and the constituents boiling 

 below 188° C. removed ; this represents about 57 to 60 per cent. ; 

 the remaining 40 per cent, is then placed in shallow vessels and 

 left a few days to crystallise, whereupon it forms a solid mass 

 having the consistency of butter. As the presence of a very small 

 quantity of adherent oil prevents the ready purification of eudes- 

 mol, we found it better to spread this impure product upon porous 

 plates, whereby the adhering oil was absorbed ; a whitish product 

 was thus obtained (pressure between drying paper was not satis- 

 factory) ; no difficulty being then experienced in purifying the 

 eudesmol. (3) By complete redistillation of the oil. A fraction 

 boiling between 269° and 289° C. is obtained ; this represents 27 

 per cent, of the original oil. On standing, this fraction crystallised 

 into a solid mass, being mostly eudesmol. 



Considerations respecting the specific gravity of Eucalyptus Oils. 

 According to the British Pharmacopoeia, 1898, Eucalyptus oil 

 should have a specific gravity of 0*910 to 0-930. When the crude 

 oil of E. niacrorhyncJia is rectified an excellent product is obtained, 

 boiling between 172'4° and 188° C, colourless, pleasant in taste 

 and smell, very volatile, and containing by the most rigid phos- 

 phoric acid test 50 to 53 per cent, of eucalyptol, while only a trace 

 of phellandrene could be detected ; and yet this rectified portion 

 of the oil, comparable in all requirements with the best Eucalyptus 

 oils, except the specific gravity test, cannot pass the tests laid down 



