XX. ABSTRACT OF PROCEEDINGS. 



acid. A large amount of evidence is brought forward to show 

 eudesmol to be intermediate in the formation of eucalyptol, and 

 that eucalyptol is derived directly from the fraction containing 

 eudesmol if the oil be kept in the crude condition for some time 

 under ascertained conditions. Oxygen is necessary to this altera- 

 tion. It is shown that the oxygen atom enters the eucalyptol 

 molecule during the formation of eudesmol, and that by the 

 natural alteration of the high boiling fraction of oils containing 

 eudesmol (E. macrorhyncha, for instance) eucalyptol is formed* 

 Eucalyptus camphora oil was found to be rich in eudesmol at the 

 time of year when distilled. The probable reason why Eucalyptus 

 oils allied to E. globulus do not contain phellandrene is described, 

 and it is shown that the oils from other groups of eucalypts are 

 dextrorotatory when their maximum eucalyptol content is reached, 

 and that they do not at that time contain phellandrene, although 

 at certain times of the year phellandrene may be present. 



The synthesis by Perkin and Thorpe 1 shows camphoronic acid 

 to be trimethyl tricarballylic acid, as was first suggested by 

 Bredt, and as eucalyptol is derived from eudesmol, and eudesmol 

 forms camphoronic acid, the question is raised whether Briihl's 

 formula for eucalyptol is correct. It is suggested that the oxygen 

 atom in eudesmol is quadrivalent, and that the peculiarity of 

 eucalyptol may be thus accounted for. From the formula 

 suggested for eudesmol camphoronic acid, as trimethyl tricar- 

 ballylic acid, can be constructed. 



2. " Observations on the determination of the Intensity of 

 Drought," by G. H. Knibbs, f.r.a.s., Lecturer in Surveying, 

 University of Sydney. 



The paper was really a continuation of the subject of Mr. H. 

 Deane's paper, read at a previous meeting. It was shown that 

 if the degree of saturation of ground was, as suggested by Mr. 

 Deane, taken as the reciprocal of the measure of drought intensity, 

 then, theoretically, it was determinable. The essential feature* 



1 Journ. Chem. Soc, 1897, 1169. 



