THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
23 
July 13, 1372.] 
It would be out of place here to enter into a de¬ 
tailed botanical description of the members of this 
large genus. For such our readers are referred to 
Mueller’s ‘ Fragmenta Phytograpliiie Australiensis’ 
or Bentham and Muellers’ ‘ Flora Australiensis. ■' 
We shall only allude to a few of the species, 
with their more striking characteristics, and im a 
further notice mention some of the products that 
they yield which have more particular therapeutic and 
chemical interest.. 
Like all the Myrtaceos, the Eucalyptus is an ever¬ 
green, but it presents the peculiarity of changing its 
aspect at three or four years of age. The leaves, at 
tirst large, sessile and horizontal, take then an 
oblique direction, or even hang vertically to the 
roots, at the end of long petioles. To speak more 
exactly, they are only simple petioles much dilated 
and presenting on both sides a uniform organization. 
These modified leaves, or phyllodes, peculiar to a 
great number of Australian plants, are generally 
coriaceous and appear to be fitted to resist atmo¬ 
spheric accidents, such as tempests, the sirocco, or 
hail. They contain numerous pellucid glands, filled 
with an essential oil that diffuses an odour which is 
strong and penetrating without being disagreeable. 
These aromatic emanations are esteemed as posses¬ 
sing properties assisting the respiration and neutra¬ 
lizing marshy miasmas; the absence of fevers in 
Australian settlements where the tree is found being 
attributed to their influence. The bark, flowers and 
fruit are all equally covered by glands containing a 
very odorous essential oil. 
The growth of the Eucalyptus is prodigiously 
rapid, even when transported far from its normal 
habitat, and nearly all the species early attain gigan¬ 
tic proportions. A tree ten years old ordinarily pre¬ 
sents the development of a well-grown oak of a 
century, and it is not rare to meet in Australia with 
specimens in their fiftieth year 160 to nearly 200 
feet high and 50 to 00 feet in circumference at the 
base. But notwithstanding this remarkable growth, 
the wood has a solidity that rivals the hardest woods 
of India, and has been used on the Australian 
coast for constructing quays, jetties etc., that ad¬ 
mirably resist the action of water. It lias also been 
utilized successfully in shipbuilding and for railway 
sleepers in India. One plank that was sent for the 
London Exhibition of 1851, but arrived too late, was 
4? metres long, 8• 50 metres wide, and 8 centimetres 
thick; and another, that was prepared for the Paris 
Exposition of 1855, but for which no vessel capable 
of conveying it could be found, was 51 metres long. 
Apart from the valuable properties they possess, 
and considered simply as ornamental plants, the 
trees of the genus Eucalyptus are of great interest 
from their beautiful appearance and the singularity 
of their foliage. And here, the first place must be 
awarded to the Eucalyptus globulus , so named from 
the form of its flower bud when covered by the oper¬ 
culum. Elegant when young, majestic when it attains 
the colossal dimensions of mature age, tliis tree has 
always a superb decorative effect. The tnmk from 
which the exterior cortical layers are often detached, 
as in the plane-tree, is smooth and asli-coloured, 
sometimes surrounded at the base by old fibrous bark. 
Its leaves, of a tint rather blue than green, play 
in the wind with effects of light and shade that re- 
* Vol. iii. pp. 185-261. 
call those of the aspen. The odour of the bark, 
flowers, leaves and fruits is analogous to that of 
Salvia officinalis. On rocky hills by the sea shore, 
where it is exposed to the weather, it forms bushy 
shrubs that flower and fructify abundantly. But in 
sheltered places it attains a height of from 60 to 70 
metres, and trees have been measured more than 100 
metres in height. In the forests the larger branches 
rarely commence below 30 metres, and many trees 
may be seen with their straight tapering trunks un¬ 
branched to a height of 60 metres. In Australia 
the Eucalyptus has proved of much sendee in pro¬ 
viding food for the honey bee, which has been in¬ 
troduced into the colony and increased in immense 
numbers. It is hoped that it will be of equal value in 
other countries where bee culture is carried on, 
especially as it provides the food at a time when 
other sources fail; for in changing its climate the 
Eucalyptus still obeys the calendar of its native 
hemisphere ; with it the spring commences in Sep¬ 
tember. Impervious to the attacks of insects, harder 
and more elastic than any other, their wood sur¬ 
passes in specific gravity that of the teak and the 
Paul tree ( Shorea robusta), long considered as pre¬ 
senting the maximum of density that could be ac¬ 
quired by ligneous fibre. 
The Eucalyptus Acajou (E. Mahogany or mar- 
ginata), popularly called in Australia the “Jarra” 
or “ Djaryl,” also merits attention. It has a vigorous 
growth, attains a colossal height, and furnishes a 
wood harder perhaps than that of E. globulus. Tliis 
wood is principally employed in maritime works, and 
better than any other resists the attacks of insects and 
the teredo. I 11 India it has been used largely on the 
railways for replacing the teak sleepers that had 
been destroyed by the dreadful ravages of the white 
ants. The wood is also susceptible of a high polish, 
and the markings are similar to the mahogany after 
which the tree is named. 
The E. rostrata, Schlecht., or red gum-tree,, is 
another large tree, furnishing a hard wood of a fine 
red colour, which is much used by the cabinet¬ 
maker. The bark yields an abundant supply of 
material to the paper-makers, which is utilized for 
packing-papers and pasteboard; filter-paper and 
blotting-paper of fair quality are also made from it. 
The E. amygdalina , Labill., or narrow-leaved 
peppermint-tree, generally attains a height of 150 
feet, but some have been met with in Australia 
measuring 480 feet in height. Its wood is very close- 
grained, and elegantly vemed. This species pro¬ 
duces the largest proportion of odoriferous oil in 
the leaves, the yield being from two to four per cent, 
of the weight of the fresh leaves and young 
branches. 
E. obliqua, L’Her, or stringy bark-tree, is a very 
large tree, having a very strong wood. The fibre of 
the bark is employed largely by the paper-makers. 
Other species are the E. microtheca , Muell., or 
“black box” and E. Stuartiana ,, F. Muell., or 
“ apple-tree,” both large trees, the latter furnishing, 
good material for the manufacture of pasteboard ;. 
E. corymbosa, Sm., with very resinous wood, and 
bark yielding good paper material; E. goniocalyx, or 
spotted gum-tree, Muell., with leaves rich in volatile- 
oil, and bark yielding excellent paper material; E. 
inophloia, Muell., E. Icucoxylon, Muell., and E. deal- 
bata , Cunn., trees of a similar description; E. side- 
roxylon, Cunn., with bark containing a peculiar resi¬ 
nous substance, which is obtained by distillation 
