14 EUCALYPTUS TREES. 
found extensively its way into technic (chiefly through Mr. Jos. 
Bosisto’s exertions), to dissolve select resins and indiarubber for 
particular varnishes, and to dilute costly scents for the manufac- 
ture of fragrant soaps. The Eucalyptus-oil is closely allied to 
the cajuput-oil (from a species of Melaleuca in India), and con- 
sists of two distinct hydro-carbonous fluids. Approximately an 
estimate of the yield of oil from the foliage of various Eucalypts 
can at once be formed by merely turning a leaf towards the light, 
when the pellucid dots of those species, which are richest in oil, 
may readily be noticed even without the aid of a magnifying 
lens. Among the Victorian species a large yield of oil (two per 
cent. or even more of the fresh foliage) may be obtained from one 
of the White Gum-trees (namely Hucalyptus amygdalina), which 
moreover is famed as the tallest tree of the globe, surpassing 
when arisen from our ferntree-gullies even the renowned Califor- 
nian Sequoia- and Wellingtonia-Pines in height, reaching to 400 
feet and even more. Oil in proportionately large quantity is also 
obtained from the foliage of several dwarf Mallee-Eucalypts, of 
the inland desert-country. 
The most important of all our Eucalypts for its timber is the 
Red Gum-tree (Eucalyptus rostrata). It lines most of the 
watercourses of all Australia, extending usually over the adjoin- 
ing valleys. Well matured wood of this species, cut at the 
season when the circulation of the sap is least active, and care- 
fully placed for gradual drying, has proved one of the most 
durable of any timbers of the whole globe. The quantity of 
tannic principle in its bark is also not inconsiderable, though 
much less than that of the wattles. This H. rostrata is readily 
obtainable in every district for the sake of comparison with E. 
globulus (or any other congeneric species); thus the specific 
characteristics can be easily contrasted, whereby a clear idea of 
the meaning of species will be gained. Both belong to the same 
section of the genus, whether they are arranged according to 
their bark or according to their anthers. The Red Gum-tree 
however has narrower leaves, with more numerous veins; the 
flowers are seated on radiating stalklets, thus forming an umbel; 
they are much smaller; several stalklets or pedicels are placed 
