110 C. E. FAWSITT AND CG. H. FISCHER. 
the C.S.T. Kor example, a specimen of oil from Eucalyptus 
Macarthuri with a ©.S.T. of 41° C. against a mixture of 
water and methyl alcohol was distilled and the last small 
portion discarded. The portion collected between 105° and 
230°, amounting to at least 95% of the original, was tested 
in regard to C.S.T. against the same mixture of methyl 
alcohol and water as before distillation. The O.S.T. was 
found to be 63°, a rise of 22° as compared with the original 
oil. A specimen of oil from H. polybractea was distilled 
and all collected up to 200° OC. Only a few drops of brown 
liquid were left in the distillation flask. The O.S.T. of the 
original oi] was 47°5°. After distillation the C.S.T. was 
59° C. To eliminate the effect due to varying proportions 
of water in the oil, the oil should either be dried before 
testing or else saturated with water. We have usually 
employed the latter method, leaving the oil in contact 
with water for at least twenty-four hours in a thermostat 
at 25° ©. The adoption of this precaution still permits of 
other changes going on in the oil such as those due to the 
absorption of oxygen and polymerisation, to which such 
oils are particularly subject. 
Method of Experiment. 
The mixture, B, with which the oil, A, is heated, must be 
varied according to the class of oil. For most oils a mix- 
ture of water with methyl alcohol was used in these 
experiments. Other mixtures such as water and ethyl 
alcohol, methyl alcohol and ethyl alcohol, glycerine and 
methyl! alcohol, and water and acetic acid have also been 
used. Although water-alcohol mixtures have been used - 
here, it is not to be assumed that an alcohol mixed with 
water makes the most suitable mixture to test these oils 
with. While some oils after mixing with water and alcohol 
appear to retain the samé C.S.T. for some hours, otber oils 
‘such as those from EH. australiana and E. polybractea show 
. rapidly altering C.S.T. This is shown by the following: 

