AND THEIR ESSENTIAL OILS. 193 



geranyl-acetate. It contained pinene as the chief terpene, 

 and ))hellandrene could not be detected in it. It 

 was rich in eucalyptol, over 60 per cent, of the crude oil 

 being that constituent. The saponification number for 

 the esters and free acid was only 3*96, representing ISS 

 per cent, of ester if calculated entirely as geranyl-acetate. 

 The amount of ester in the oil of this species is thus very 

 small. The average yield of oil was 0482 per cent. — a 

 comparatively small one for a commercial oil. 



The crude oil had specific gravity at 15^ C. — 0"9075 ; 

 rotation aj) = + 10*6; refractive index at 24° = 14653 ; 

 and was soluble in 6 volumes 70 per cent, alcohol. 



On rectification, the usual amount of acid water an.d 

 volatile aldehydes were obtained below 164° C. (corr.), "it 

 which temperature the oil commenced to distil. Between 

 164-1730 33 per cent, distilled; between 173-1980 57 per 

 cent.; between 198-265° 5 per cent, distilled. The high 

 boiling fraction contained a constituent with rotation to 

 the right, but it was not isolated. The following results 

 were obtained with the several fractions : — 



Sp. Gr. at Rotation a ^^^- ^"''^'^ 



15° C. Kotation a^. ^^ j^^o (. 



First fraction 0-8979 ... +15-8° ... 14629 



Second frdction... ()'9ll9 ... +8-4 ... 1-4(538 



Third traction 0'9231 ... + 5'2 ... 1-480.5 



The eucalyptol was determined by the resorciuol method 

 in that portion of the oil distilling below 198° C. and cal- 

 culated for the crude oil, which was shown to contain 64 

 per cent, of that constituent. The rectified oil had a yel- 

 lowish tinge, a ])eculiarity often found with the eucalyptol- 

 pinene oils distilled from the leaves of the smooth-baik 

 Gums like J'J . r/lobuJiffi, E. goTiiorali/x, &c. Pinene was 

 isolated from the first fraction, and proved to be that sub- 

 stance by the formation of the nitrosochloride, which 

 melted at the correct temperature. 



The oil from the leaves of E. M acarthuri of New South 

 Wales appears never to contain less than 60 per cent, of 

 geranyl-acetate at any time, this ester often rising to 75 

 per cent., and one determination of the oil from the 

 " suckers " showed that it contained over 77 per cent, of 

 geranyl-acetate. Eucalyptol does Mot appear to occur 

 in the oil of ?J . M acarthuri, although pinene is usually 

 present in small amount. 



