58 



ESSENTIAL OIL. Material for distillation was collected at Tunbridge, 

 r/asmania, in June, tgi2. The yield of oil was i per cent. The crude oil was 

 lighl olive-brown in colour! had a terpene-like odour, and consisted principally 

 oi lavo-rotatorv pinene; cineol and eudesmol were both present, the latter in 

 quantity, as it crystallised from the higher boiling fraction. The so-called 

 "Cabbage or Weeping Gum" is common both in Australia and Tasmania. Oil 

 was first distilled from this Eucalypt by Mr. Marsden, at Muloon, near Boro, 

 N.S.W., in February, 1908, and it was brought under our notice by Mr. Farrell, 

 of the Australian Eucalyptus Oil Company, on account of its strong odour of 

 turpentine, and the low temperature at which it boiled. When submitted to us 

 it was a colourless oil, as it had been rectified, and was found to contain a small 

 amount of cineol, and to consist almost entirely of laevo-rotatory pinene, with 

 some eudesmol. In September, iqio, Mr. Farrell noted this species growing 

 at Monga, N.S.W., and he had the leaves distilled, and submitted the crude oil 

 to us for investigation. The oil was light olive-brown in colour, had an odour 

 of turpentine, was very mobile, and besides consisting largely of laevo-rotatory 

 pinene, contained some cineol and eudesmol. Even more pinene was present 

 than in the Tasmanian oil, but this may be due to the difference in the time of 

 the year, or partly to the mode of distillation, as the Monga oil had been distilled 

 from an ordinary pot-tank still, which naturally does not bring over the high 

 boiling constituents so completely as when the steam is supplied from a boiler. The 

 Monga oil had specific gravity at 15° C. = 0-8766; rotation a — 32-5°; refractive 

 index at 20 = 1-4679; and contained n per cent, of cineol by the resorcinol 

 method. Over 80 per cent, of the total oil distilled below 170 C. (corr.). 



The oil from the Tasmanian trees (our own distilling) had specific gravity 

 at 15 C. = 0-8925 ; rotation a u - - 22-4°; refractive index at 20 = 1-4752, and 

 was insoluble in 10 volumes 80 per cent, alcohol. The saponification number 

 for the esters and free acid was yz. 



On rectification, a very small amount of acid water and volatile aldehydes 

 came over below 157 C. (corr.). Between 157-172° 66 per cent, distilled; 

 and between 172-192°, 9 per cent. ; the temperature then quickly rose to 265°, 

 only a few drops distilling; and between 265-282°, 20 per cent, distilled, which 

 largely consisted of crystallised eudesmol and the sesquiterpene. These fractions 

 gave the following results : — 



First fraction, sp. gr. at 15° C. = 0-8710; rotation a D - - 35-2°; refractive 



index at 20° = 1-4658. 



Second ,, ,, ,, = 0-8809; rotation a D 21-2°; refractive 



index at 20° = 1-4671. 



Third ,, ,, ,, = 0-9418; rotation, not taken; refractive 



index at 20° = 1-5010. 

 The cineol was determined by the resorcinol method in the portion distilling 

 below 192° C, and when calculated for the original oil represented 9 per 

 cent. ; the absorption, however, might include some eudesmol brought 

 over in the distillate. The pinene was determined in the first fraction, and an 

 amount equal to 30 per cent, of the total oil came over between 156-157° C. It 

 had an odour resembling ordinary turpentine. The specific gravity at 15° C. 

 = o-866i ; rotation </„ - - 38-1°; and refractive index at 20° = 1-4650. The 

 nitrosochloride was easily prepared with it, and this melted at the correct 

 temperature. It may be assumed, therefore, that 50 or 60 per cent, of the oil 

 of this Eucalyptus consists of laevo-rotatory pinene, and this is confirmed by 

 both the Monga and Muloon samples. Whilst the chief constituent of the oil 

 of this species is pinene, that of the oil of E. coriacea is phellandrene. Other 

 differences are also shown between the oils of these two species. 



