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



formulated on researches limited principally to the oil of E. 

 globulus, which belongs only to a type of Eucalyptus oils, and 

 which may very well be styled the globulus type. This matter is 

 of importance also, because it may eventually be that a large pro- 

 portion of the Eucalyptus oil of commerce will be distilled from 

 the leaves of E. macrorhyncha for the reason that it will be obtained 

 practically as a bye-product connected with the extraction of 

 myrticolorin. The yield is not sufficiently large for the extraction 

 to be remunerative if the oil alone were the main product sought 

 for, unless the stearoptene may be found to be of value, but in 

 connection with the extraction of myrticolorin it has great possi- 

 bilities. 



Eucalyptol determination by Phosphoric Acid. 



It will be noticed that the crude oil of Eucalyptus macrorhyncha 

 did not react satisfactorily with phosphoric acid, although a large 

 percentage of eucalyptol was present in the oil, as will be seen by 

 referring to the table of results. It is only after the oil has been 

 redistilled, whereby the fractions containing the eucalyptol are 

 separated from the eudesmol and other constituents boiling at a 

 high temperature, that the reaction with phosphoric acid is at all 

 satisfactory. This test cannot be considered a satisfactory quali- 

 tative one for eucalyptol in some crude Eucalyptus oils, and with 

 the crude oil of M macrorhyncha it could not be used for quanta - 

 tive determinations. Other constituents besides eudesmol may 

 have an adverse influence. When ice was added to the water 

 bath a crystalline product was obtained, but with difficulty, and 

 the reaction was far from satisfactory, and no attempt was made 

 to determine the eucalyptol content quantitatively in the crude 

 oil of E. macrorhyncha. It appears, therefore, that crude oils of 

 unknown species should be redistilled before a decision can be 

 arrived at as to the absence or otherwise of eucalyptol, when phos- 

 phoric acid is used. 



The quantitative eucalyptol determinations were carried out in 

 the following manner; the phosphoric acid was added by drops from 

 a burette to 10 grams of the oil, using a cold water bath ; thorough 



