74 H. G. SMITH. 



aromatic than cuminaldehyde, and it differs from that aldehyde 

 in having a somewhat high rotation to the left, a less specific 

 gravity, a lower boiling point, and its oxime melts at a much 

 higher temperature. It is now being further investigated.] T 



It must not be thought that the odour of some Eucalyptus oils 

 is entirely due to this ester. In the oil of E. patentinervis a very 

 small quantity of an ester is present, but the odour of the saponified 

 oil is excellent, resembling somewhat that of Bergamot oil, and 

 there is little doubt but that either linalool or geraniol is present. 

 Acetylation of the oil showed no less than 16-5 per cent, of free 

 alcohol to be present in the oil of this species, calculated as 

 linalool. A small quantity of citral was removed from the oil of 

 this species (E. patentinervis) by acid sodium sulphite, and deter- 

 mined by the formation of the alcyl-/3-naphtocinchoninic acid 

 characteristic of citral, 2 and it seems reasonable to suppose that 

 this citral has some connection with the aromatic alcohol present 

 in the oil of this species. The leaves have a lemon odour when 

 crushed and are quite aromatic. It was previously supposed that 

 botanically E. patentinervis was connected with E. resinifera but 

 the chemical determination of the constituents of its oil shows it 

 to have no immediate connection with that species, but to be allied 

 to E. botryoides and perhaps more closely to E. saligna. 



In the list of known constituents of the oil of E. globulus, 

 published by Schimmel and Co., report April 1897, we find amyl 

 alcohol mentioned, it may be considered that this amyl alcohol 

 was originally derived from the ester now being described, and 

 goes to show that even in an oil like that of E. globulus an ester 

 is present at some time, although when distilled these oils usually 

 consist largely of pinene and eucalyptol. 



The oil of Eucalyptus aggregata. 



The crude oil of the "Black Gum " E. aggregata, is very fluid, 

 much like water in that respect, it is light orange-brown in colour 



1 Added 25 July, 1900. 



2 There is no doubt but that citral does occur naturally in some 

 Eucalyptus oils. 



