114 C. KE. FAWSITT AND C. H. FISCHER. 


Table VI. 
A, Oil from £. australiana. 
B, Acetic acid , water 
Addition to Oil. Cis Ea 
0 37-2 
9-1 pinene ... ie Bel Dee: 
9:1 #. dives residues cca pee) Bee 
) 9b cineoly se: nea <2 1 2D Re 




It will be seen from these measurements that a change 
in the composition by 1% pinene produces a difference in 
the O.S.T. of 1°-—2°. As these temperatures can be read 
with an accuracy of about ;5 C., it will be understood 
that the method is a very sensitive one for the detection 
of differences in the composition of the oil. 
Some physical determinations on oil, such as a determin- 
ation of the density, are directly connected with the com- 
position of the oil as determined by chemical analysis. For 
a substance like eucalyptus oil this ‘analytical composition’ 
is expressly what we want to know. The determination 
of miscibility and in particular of O.S.T. is not so directly 
related to the analytical composition, as to the true com- 
position, in which all possible molecular complexes in 
solution play a part. A miscibility test does not appear 
therefore to have quite the same value for a eucalyptus 
oil as it has for some other mixtures, but the carrying out 
of this work has had its value in suggesting other avenues 
of research. 
We are indebted to Mr. A. R. Penfold of the Techno- 
logical Museum, Sydney, for supplying us with several 
samples of eucalyptus oil. 
- Chemical Department, 
University of Sydney. 

