MYKTACE^B 349
and Smith,^1 who have now re-named the mainland tree Eucalyptus
Australiana.
When these scientists studied theEucalyptsof Tasmania, Labillardier's
species of Eucalyptus amygdalina necessarily received much attention,
as it was from that island he obtained his material, which, of course,
stands as the authenticated species. The name, however, has long since
been also given to a tree on the mainland, and it was only when investi-
gating the species for the above research, that differences were detected
in the two trees, and these have since been followed up. In fact, the
differences were so marked that even then they raised the continental
form to varietal rank under the name of Eucalpytus amygdalina, var..
Australiana, being loath to introduce another species name to the already
long list of eucalypts. They were prepared to let it stand at that, but
the technology of this eucalyptus has since come so much to the front
in the commercial world, that they considered it best in the interest of
applied, as well as pure science, to give it specific rank, for which they
propose the name Eucalyptus Australiana for the mainland tree.
The probability of this oil becoming one of the most important pro-
ducers of eucalyptus oil induced the authors to investigate it very fully.
They were able to show that, by fractional separation at stated times
during the primary distillation, an oil richer in eucalyptol could be ob-
tained, particularly if the portion which came over during the first hour
was separated. The eucalyptol was thus more easily distilled than the
alcoholic bodies and other oil constituents in the leaf. By taking ad-
vantage of this peculiarity, and working the trees growing at Nerri-
gundah, Yourie, and neighbouring districts of New South Wales in the
same way, it has been possible to produce a product of a fairly constant
character, high in eucalyptol-content, and answering to the requirements
demanded for a first-class pharmaceutical eucalyptus oil. The results
have been so satisfactory that the species is, at the above localities, now
worked in this way, the first-hour oil being sold for pharmaceutical pur-
poses, the remainder being employed for mineral separation and for other
industrial uses.
The remarkably high yield of oil given by this species enables this
mode of working to be profitably undertaken, and the amount obtained
during the first hour is almost as great as that from many other cineol-
producing species when these are distilled right out. The second-hour
oil thus becomes practically a subsidiary product. Little advantage ap-
pears to be derived from distilling the leaves for a longer period than
two hours, as the amount of oil thus obtained is but small. The first-
hour oil, when properly prepared, is almost water-white, which fact ap-
pears to be due to the presence of the phenol, tasmanol—common to-
ting class—containing a methoxyl group, a constitution which does not
permit the formation of a quinone, as is the case with the oils of the
other large class of cineol-producing eucalypts. The amount of volatile
aldehydes in the crude oil is but small, so that altogether no rectification
of the first-hour oil is needed before placing it on the market.
The crude oil has the following characters :—
Specific gravity 0-9157
Optical rotation + 2*8°
Refractive index 1-4644 at 20°
Eucalyptol..70 per cent.
1
Jour. Proc. Roy. Soc., N.S.W., xlix., 514.