THE EUCALYPTUS GLOBULUS.

Globe, Volume I, Issue 69, 20 August 1874, Page 4

THE EUCALYPTUS GLOBULUS.

The Medical Times and Gazelle, of May 16th, publishes the following interesting comments on the properties and uses of the Eucalyptus Globulus, from a lecture delivered by Professor Bently, at the Koval Botanic Society’s Gardens, in Kegent Paik The first and most important influence which this tree exerts, and that which has brought it more especially into uotke ? iaits

power of destroying the malarious agency which is supposed to cause fever in marshy districts, from which circumstance it has been called the “ fever destroying tree.”

It is in this respect commonly regarded as being serviceable in two ways—first, by the far spreading roots of this gigantic tree acting like a sponge, as it were, and thus pumping up water and draining the ground ; and, secondly by emitting odorous antispeptic emanations from its leaves. Probably the influence of the latter is but small ; although I am by no moans of the opinion entertained by some writers, that these emanations are without effect. Ido not certainly believe as has been recently stated that the branches of of a solitary Eucalyptus tree can have had any effect in neutralising the malarious influence of a district previously constantly infected with fever ; but I do think that the foliage of groves of Eucalyptus trees, by diffusing an agreeable aromatic camphoraceous stimulating odour in the surrounding air, docs have an" appreciable influence in neutralising marshy miasmas, thus improving the healthiness of the district. That influence is however, in my opinion, unquestionably produced by the power the roots possess of absorbing the water from the soil. It is stated that a Eucalyptus tree absorbs as much as ten times its weight of water from the soil ; and hence the enormous suction power of masses of such trees may be in some degree judged of, so that, where thickly planted in marshy places “ the subsoil is drained in a little while as though by extensive piping.” That the main influence of the Eucalyptus tree is thus due to the absorptive power of the roots is also borne out by the fact that other plants of rapid growth, when planted in marshy districts, have a sensible effect in diminishing their malarious influence. This is notably the case with the sunflower, which is grown for this purpose to a large extent in the swampy regions of the Punjaub, and other parts of the world ; and the effect has been that districts which were previously remarkable for their insalubrity, are now said to be entirely free from miasmatic fever.

But whatever may be the cause or causes which render a marshy district thus com paratively healthy to what it was before the introduction of the Eucalyptus trees in the neighborhood, the fact is unquestionable, and is now testified to in various parts of the world. Thus, at the Cape, in a very few years, the cultivation of the Eucalyptus has completely changed the climatic condition of the unhealthy parts of the colony ; and in Algeria, where it has been tried on a large scale in a district previously noted for its pestilential air and consequent prevalence of fever, not a single case now occurs, although the trees are not more than nine feet high ; and in the neighborhood of Constantia it is also stated that at another noted fever-spot, covered with marsh water both in winter and summer, in live years the whole district was dried up by 14,000 of these trees, and the inhabitants now enjoy excellent health. In Cuba, again, marsh diseases arc fast disappearing from the unhealthydistricts where this tree has been introduced. In the department of the Yar it is also said that a station-house situated at one end of a railway viaduct, so pestilential that the officials could not be kept there longer than a year, is now as healthy as any other place on the line, in consequence of the planting of a few Eucalyptus trees. Numerous other instances might be cited to the same effect as having occurred in France, Spain, Italy and Germany, and other parts of the world ; and we cannot doubt therefore that although the effects have been to some extent probably exaggerated, the statements are substantially correct, and that this tree does possess a most beneficial effect in neutralising and improving the malarious influence of marshy districts. *******

Among the products obtainable from the Eucalyptus wood we must not forget the potash more "particularly as this alkali can be obtained without sacrifice of any valuable timber, and from localities not accessible to the wood trade.” The richness in potash of this wood may be estimated by the fact that Baron Yon Mueller found that the ashes of these trees *• contained a larger proportion of potash than the elm or maple, which are the trees most esteemed for that purpose in America. The yield from the latter trees is estimated at 10 per cent of the ashes, while that from the Eucalyptus is 21 per cent.” * * * * *

Another very important product of the Eucalypti is the essential oil which may be obtained in large quantities by aqueous distillation from the leaves. This oil is stored up in pellucid glands contained in the leaves, readily observed when these are held up to the light by the semi-transparent appearance they then exhibit. These oils are prepared on a very largo scale by Mr Bosisto of Melbourne, and now form an important article of commerce with this country and elsewhere, Mr Bosisto alone produces about 1000 lbs of Plncalyptus oil per month. These oils generally have a somewhat camphoraccous smell ; but the odour differs in the various species and the oil obtained from E. citriodora has a pleasant citron-like odour, *******

We have now in conclusion to allude very briefly to the medical properties of the Eucalyptus Globulus. The febrifugal properties of the bark and leaves of this plant have been testified to by many practitioners —as M. Pepin, Dr Oarlotti, Dr Lorinser, Professor Gubler, Dr Keller, Dr McLean, and more especially of late years by Dr Gimbert, who has published two important communications on the subject. It is said to be a valuable remedy, and more especially in intermittent fevers and bronchitis. Probably some of the exaggerated statements that have been made in reference to the efficacy of the Eucalyptus bark and leaves in fevers have arisen under the mistaken idea that the bark contained an alkaloid resembling, if not identical with quinine, the well-known alkaloid of cinchona barks. But the experiments of Mr Broughton, the Government chemist of Oatacamund, entirely disproves this; for upon careful examination of the bark and leaves, Mr Broughton states that neither quinine nor the other alkaloids of cinchona bark, as quinidine, cinchonine, or cinchonodine, exist in the plant in any proportion. What properties the plant possesses would appear, therefore, so far as known at present, to be due essentially to Hhe presence of eucalyptal, the principal constituent of eucalyptus oil. This substance. in its chemical characters, resembles camphor. Dr Gunbert has recently introduced anew method of dressing wounds by using eucalyptus leaves instead of lint. The leaves are simply laid on the wounds, uud it

is said that their balsamic nature not only c ircs, but removes all unpleasant odour. Another way of using eucalyptus leaves is in the form of cigarettes. They are reputed to be efficacious in bronchial and asthmatic affections and in other ways.