262 AUSTRALIAN NATIVE PLANTS. 
Tasmania, also, a company has been formed for the distillation of 
different species of Eucalyptus. A statement made in a previous 
report that the Australian oil from Lucalyptus amygdalina contains 
no Eucalyptol, and is inferior in this respect to the Lucalypius 
globulus oil from Algeria and California, was subsequently chal- 
lenged and stigmatised as ‘distinctly erroneous.’ Messrs. 
Schimmel, however, now reaffirm that statement, and say that the 
fraction of the amygdalina oil, separable at a temperature of 
176°-177°C, has a specific gravity of 0.886 at 15°C (Eucalyptol has 
a specific gravity of 0.930), and is probably a mixture of terpene 
(Eucalyptene, C,, H,,) and a small quantity of cymol.’”’ (Pharm. 
Fourn., 1888.) 
The following excerpt from the Zndia-rubber and Gutta-percha 
Fournal, 1887, on the subject of Eucalyptus leaves for preventing 
and removing scale in boilers is interesting, and may perhaps be 
mentioned under this head, pending the settlement of the question 
as to what constituent or constituents in the leaves causes the 
action stated. The matter is worthy of consideration by steam- 
users in Australia, to whom illimitable supplies of gum leaves are 
available for experiment. : 
“‘ Boiler cleaning is an important subject to all users of steam 
power. The extract from the leaves of the Lucalyp/us, or blue 
gum (which has recently been found so efficacious for the above- 
named purpose), is procured by boiling the leaves in a battery of 
boilers under a pressure of 4olb. of steam. Twenty tons of 
leaves are boiled every day, and the boilers, after constant use of 
two years, are as sound as when they came from the shop. 
Extract of Kucalyptus globulus, or blue gum, has been tested by 
Professor E. W. Hilgard, of the Agricultural Department of the 
University of California, in respect to its contents of tannin, its 
taste being highly astringent. It was found that a standardised 
tannin solution would precipitate -337 per cent. only of tannin; 
that beyond these limits either tannin or gelatine solution would 
produce a precipitate of about equal amount. After removing 
the tannin as far as possible, by digestion with animal membrane, 
the acid reaction shown by the extract was found to be equivalent 
to only *127 per cent. of sulphuric acid, an amount so. small that 
win < 
