8 9 



ESSENTIAL OIL. Leaves and terminal branchlets for distillation were 

 obtained from Laggan, near Crookwell, New South Wales, in May, 1901. The 

 yield of oil was 0-7 per cent. The crude oil was amber-coloured, and had an 

 almond-like odour, indicating the probable presence of benzaldehyde. This odour 

 appears to be characteristic of the oil of this species, and has not, so far, been 

 detected in any other Eucalyptus oil. It was first noticed in a sample of oil 

 presented by Mr. J. J. Hook to the Goulburn Museum. 



In April, 1901, a commercial sample of freshly-distilled oil from this 

 species was submitted to us for determination. It was found to be identical 

 in composition with the specimen in the Goulburn Museum. 



The oil of this species was rich in cineol ; it contained pinene, but phellan- 

 drene was absent. On agitating a portion of the oil with acid sodium 

 sulphite a small amount of a crystalline compound was obtained; this 

 was separated, purified, decomposed, and the aldehyde removed by ether. The 

 product had a marked odour of benzaldehyde, but an attempt to oxidise it to 

 benzoic acid was not successful, so that its identity yet remains to be proved. 



The crude oil from the Laggan material had specific gravity at 15 C. = 

 0-9122; rotation a D + 6-7; refractive index at 20 = 1-4654, and was soluble 

 in 'ij volumes 70 per cent, alcohol. The saponification number for the esters 

 and free acid was 4-6. 



On rectification, 2 per cent, distilled below 162 C. (corr.). Between 

 162-180, 83 per cent, distilled ; between 180-188, 6 per cent, came over, and 

 between 188-250, 4 per cent, distilled. These fractions gave the following 

 results : 



First fraction, sp. gr. at 15 C. = : 0-9083 ; rotation a D + 8-2. 

 Second ,, ,, : 0-9216; ,, not taken. 



Third ,, ,, ,, = 0-9281 ; ,, ,, 



The cineol, determined by the phosphoric acid method in the first fraction, 

 was 55 per cent. (O.M.), indicating about 48 per cent, in the crude oil. 



The third fraction consisted largely of the sesquiterpene. 



The above sample was stored in the dark, and in November, 1919, 

 again analysed. Not much alteration had taken place during the time it had 

 been kept, with the exception that the specific gravity had increased a little. 

 The rotation had also altered, and showed a slightly higher dextro-rotation, 

 evidently due to the diminution in rotation of a laevo-rotatory constituent. The 

 odour of benzaldehyde was very pronounced in the rectified oil, particularly 

 after the cineol had been fixed by phosphoric' acid. 87 per cent, distilled below 

 190 C. The crude oil and the rectified portion gave the following results : 



Crude oil, sp gr. at 15 C. := 0-9192; rotation a v + 7-8; refractive index 



at 20 = 1-4664. 

 Rectified portion ,, ,, : 0-9113; rotation D + 9-4; refractive index 



at 20 = 1-4607. 



The cineol was determined by the resorcinol method in the rectified 

 portion ; the result was 63 per cent, when calculated for the crude oil. 

 By the rapid phosphoric acid method it was 58 per cent. 



In the year 1908, Mr. W. T. Farrell, of the Australian Eucalyptus Oil Co., 

 submitted a sample of Eucalyptus oil he was distilling for commercial purposes 

 from a tree known in the South Coast district of New South Wales as " Ribbon 

 Gum." This oil indicated the presence of benzaldehyde, and in other respects, 

 particularly the botanical material, agreed with the species we had previously 



50068 G 



