20 



entered upon the preparation of these oils on a large scale, with 

 what success (commercially speaking) I am, however, not pre- 

 pared to state. The similarity in the general properties of these- 

 oils is so great that it may suffice to make some general allusions 

 to them here, referring the reader for fuller information to the 

 short descriptive account of each of the various oils given under 

 their respective headings further on. They are all soluble in alt 

 proportions in turpentine, both fat and drying oils, benzine r 

 naptha, ether, chloroform, and absolute alcohol. Spirits of wine 

 dissolves them pretty freely ; and water on being agitated with 

 an excess takes up in most instances about 1 per cent, by weight. 



Inasmuch as they all possess medicinal properties, they will no- 

 doubt ultimately meet with extensive application in medicine. 



As solvents for a great variety of resinous substances, they are 

 all more or less excellent ; amongst other resins dissolved by 

 them, is, singular to say, the fossil Kaurie gum (Dammara 

 Amtralis) of New Zealand, a resin, the exportation of which, in 

 large quantities has hitherto been retarded in consequence of the 

 difficulty experienced in bringing it into perfect solution. From> 

 this it will be seen that these oils are well adapted for the prepa- 

 ration of varnishes and lackers. 



For illuminating purposes they are equally valuable. In alt 

 cases they burn with a brilliant flame, almost equal, and i 

 some cases even superior, to that from the best American kero- 

 sene, whilst the odor, if any, produced by their combustion, is 

 more agreeable, and, unlike it, they leave no stain upon paper 

 or clothing. Notwithstanding that the quantity of oil obtained 

 from each species was determined with considerable accuracy,, 

 the results cannot be regarded as absolutely constant under all 

 circumstances ; great variations will be perceptible in the pro- 

 ducing powers of oil-bearing trees, due to differences in age (ex- 

 periments proved that a much larger yield was obtained from the 

 more perfectly matured leaf than from those of younger growth) r 

 in the localities where grown, whether in high or low, moist or 

 dry ground, in the time of year when the leaves were gathered,, 

 and in climatic influences generally. 



The apparatus, employed by me, when preparing any of the 

 Eucalyptine oils, was the ordinary still, inside of which was 

 placed a strong wire-net basket, about two or three inches less in, 

 diameter than the still, and having legs so as to raise it about an 

 inch from the bottom. By this arrangement the material ope- 



