AND THEIR ESSENTIAL OILS. 19 



CHEMISTRY. 



Essential Oil. This material was collected at Iiiterlaken 

 in May, 1912, and was distilled in the fresh condition just 

 as would be done commercially. The average yield of oil 

 from the leaves and terminal branchlets was 0'387 per cent. 

 The crude oil was dark -coloured, and had a terpene odour, 

 together with that of eucalyptol. The chief constituents 

 in the oil of this species are dextro-rotatory pinene, laevo- 

 rotatory phellandrene, eucalyptol, some sesquiterpene, and 

 a small amount of ester. 



The crude oil had specific gravity at 15 C. s* 0'9014; 

 rotation a D = + T5 O ; refractive index at 1.8 =: 1'4752 ; 

 and was soluble in 4 volumes 80 per cent, alcohol. 



On rectification, a small amount of acid water and vola- 

 tile aldehydes came over below 165 C. (corr.). Between 

 165-1730 - C. 30 per cent, distilled; between 173-198 C. 

 52 per cent. ; the thermometer then rose to 254, and 

 between 254-270 C. 14 per cent, distilled. The fractions 

 gave the following results: 



Sp. CT. at Ref. Index 



We Rotation a D . at 18 C . 



First fraction 0-8813 ... +5-4 ... 1-4680 



Second fraction .... 0'8930 ... -4*2 ... J-4686 

 Third fraction 0-9377 ... + 8-9 1-5013 



The eucalyptol was determined in the oil distilling below 

 198 and calculated for the crude oil, which was thus 

 shown to contain 41 per cent, of that constituent. 



The saponification number for the esters and free acid 

 was 6'7. The results of this investigation show the oil of 

 this species to be quite distinct from that of E . camphor a 

 of New South Wales. E . Gunnii has no value as an oil- 

 producing tree, as the yield is small, and the main con- 

 stituents only of an ordinary nature. 



EUCALYPTUS LINEARIS, A. Cunn. 



f" White Peppermint." ) 

 BOTANY. 



Remarks. It has been customary to regard the smooth- 

 barked narrow-leaved Eucalyptus growing near Hobart, 

 and distributed throughout Tasmania generally, as this 

 species, but in going over the literature and specimens pro- 

 curable to-day it would seem that such a classification is 

 'wj-rAi correct. 



