219 



About 20 CCS. of (b) distilled betw&en 136 aud IBS'" C, 

 and then the temperature rose slowly to 140° C. The follow- 

 ing constants were obtained 





Sample a. 



Sample b 



Specific gravity 



... 0-9516 



0-9553 



Rotation 



... -67-92° 



-72-22° 



Refractive index at 20° C. 



... 1-4888 



1-4921 



Dispersion 



... 0-01325 



0-01363 



The preparation of the oxime was tried on these samples, 

 but the product was only crystallized with great difficulty. 

 By carefully crystallizing from chloroform, however, minute 

 crystals were obtained; one crystal grew sufficiently to permit 

 of its removal by mechanical means. When washed and dried 

 it melted at 84-85 '5° C. As this aldehyde is not identical 

 with any yet separated from Eucalyptus oil, it is proposed 

 to call it cneoral. The amount available did not permit of 

 any extensive work being performed on it, and it is possible 

 that it may later be proved to be identical with some aldehyde 

 already separated from some other Eucalyptus oil. 



Conclusion. — -This oil appears to contain four aldehydes — 

 cuminal, aromadendral, cryptal, and a fourth one, which is 

 here called cneoral. The first three of these agree with the 

 aldehydes separate'd by H. G. Smith (loc. cit.J from 

 Eucalyptus oils. 



E. Sesquiterpene. 



The last fraction in the distillation of the oil contained 

 a sesquiterpene, which answered to H. G. Smith's tests for 

 aromadendrene. The oil which was left unabsorbed after 

 shaking the higher boiling fractions of the crude oil with a 

 35 per cent, sodium bisulphite solution (to remove aldehydes) 

 was equivalent to 4 per cent, of the crude oil and had a 

 rotation of —15*1°. As the quantity of sesquiterpene pre- 

 sent was small, the residual oil left after refining the crude 

 oil on a commercial scale was shaken with a solution of sodium 

 bisulphite (35 per cent.). About one-third of the oil was not 

 absorbed by this treatment, and it gave the following con- 

 stants : — Specific gravity — 09421 ; rotation = — 2'55° ; refrac- 

 tive index = 1*4800 ; dispersion, 0"01086. This sample was 

 shaken with a solution of resorcinol (50 per cent.) to remove 

 the cineol, and then steam distilled. The resulting oil, which 

 constituted 69 per cent, of the previous fraction, was prac- 

 tically colourless and gave the following constants: — Specific 

 gravity = 0*9356; rotation^ — 2'7°; refractive index at 20° C. 

 = 1-4788; dispersion, 0-01055. 



Conclusion. — This oil contains a small percentage of a 

 sesquiterpene (not more than about 2 per cent.), which appears 

 to be aromadendrene. 

 g2 



