(d) TERPINEOL FROM THE OIL OF E. DIVERSICOLOR. 



The saponification number for the original oil of this species was even higher 

 than for that of E. carnea. 



When rectified, 32 per cent, remained, boiling above 190 C. This portion 

 had saponification number 129-7 ^Y heating, and 34 in the cold with two hours' 

 contact. It was then saponified in the usual way and the volatile acids 

 separated and determined, the result being 86-9 per cent, barium-acetate and 

 13-1 per cent, barium-butyrate. The saponified oil was subjected to repeated 

 distillation under reduced pressure until a fraction was obtained boiling at 

 99-100 C. at 10 millimetres. This had : 



Specific gravity at 15 C. ... ... ... ... ... : 0-940. 



Rotation a + 21-5 



Refractive index at 20 ... ... ... ... ... = 1-4831. 



Phenylurethane melted at ... ... ... ... 111 C. 



It eventually gave a good yield of terpin hydrate when repeatedly shaken 

 with 5 per cent, sulphuric acid. 



The terpineol in the oil of this species was apparently combined with both 

 acetic and butyric acids, but chiefly with the former. It may be assumed, 

 therefore, that terpinyl-acetate is a constant constituent in the oils of the earlier 

 members of the genus, and that the alcohol is highly dextro-rotatory. In the 

 oils of the more recent groups the predominant terpineol appears to be mostly 

 Isevo-rotatorv. 



Pipcritol, the corresponding Alcohol to 



Pipcritonc. 



THIS secondary alcohol occurs in the oils of the " Peppermint " group of 

 Eucalypts, and although several members of this group give an oil containing 

 only a comparatively small amount of piperitone (the peppermint ketone of 

 Eucalyptus oils), yet a fair quantity of an alcohol other than terpineol or 

 geraniol is present. This investigation showed this alcohol to be the corres- 

 ponding one to piperitone, and is, therefore, named piperitol. It is an unsaturated 

 alcohol. 



Although it occurs naturally in a number of these oils, yet it has not, so 

 far, been possible to form it by the reduction of the ketone, the reduction 

 product, with sodium amalgam particularly, consisting of a solid dimolecular 

 ketone of quite a definite character. (See also the article on piperitone in 



this work.) 



Experience had shown us that one of the best oils for the preparation of 

 this alcohol was that derived from E. radiata, and for this purpose material for 

 distillation was obtained from Hill Top, New South Wales, in November, 1919. 

 The yield of oil was 2-9 per cent. The oil of this Eucalypt consists very largely 

 of phellandrene, and the leaves have the phellandrene venation particularly 



well-defined. 



That ketonic and alcoholic bodies were only present in small amount 

 is indicated from the specific gravity of the crude oil, this being only 0-8643 at 

 15 C. It was thus fortunate that the yield was so good, particularly as it was 

 necessary to employ a considerable quantity of oil in order to prepare sufficient 

 alcohol for investigation. 



