EUCALYPTUS. None of the species of Eucalyptus are capable of standing the climate of the United States, except the warmer parts of Florida and some portions of California. Ten degrees of frost will kill them. E. globulus, or the blue gum tree of New South Wales is a fast growing, magnificent, and useful tree where it will stand the climate. TJnfortunately, it is not hardy, except where we have stated, and possi bly in favorable situations on the Gulf coast, and, probably, in southern Texas, near the coast line. As showing the rapidity of growth of the Euca lyptus, where it is hardy, in California, at two years old, the trees have reached a height of from fifteen to twenty-five feet, and after three years' growth a height of from thirty-five to forty feet, and from five to nine inches in diameter of stem. They are well adapted to dry situations. The principal varieties experimented with, in Cali fornia, were E. globulus; paniculata; tereticornis; vitninalis; hemiph,loia; and obliqua. The follow ing are some of the more valuable qualities of the genus Euealyptii: The remarkable solidity, hardness, and durability of the timber of some of the species is well known. The large propor tion of potash, amounting to twenty per cent., in the ashes of these trees has been pointed out by Baron Von Mueller. The barks of E. 7'08 trata, E . obligua, E. goniocalyx, and E. corymbosa are used for making paper. The barks of many has similar action to the ordinary manna, and exudes in large quantities through punctures or wounds made in the young bark. Another product of great importance is the essential oils. These oils generally have a camphoraceoua smell, the odor differing in the various species; species are used extensively for tanning. A substance called Australian manna is yielded by E. mannifera, E. viminalis, and other species. This manna occurs in small, rounded, opaque, whitish masses, with an agreeable sweetish taste; it contains somewhat similar constituents, and that from E. citriodora has a pleasant citron like flavor. The oil from E. oleosa is used as a solvent for resins in the preparation of varnishes.
The oils of E. amygdaiina, E. glolralus and E. citriodora are used for diluting the more delicate. essential oils used in perfumery. These oils, -contain a substance called Eucalyptol, a liquid body, having chemical characters resembling camphor. The fehrifugal properties of the bark .and leaves of E. globulus have been noted by many medical practitioners. Although careful examination of the bark and leaves has proved that neither quinine nor the other alkaloids of cinehona bark exist in the plent, yet it is .admitted to possess antiperiodic properties, which are supposed to be due to the presence of Eucalyptol. Finally, cigarettes made of Euca lyptus leaves are reputed to be useful in bronchial and asthmatic affections. Considering the rapidity of growth, the value of the timber, the healthy emanations from the foliage, the com mercial importance of the essential oils, and the beauty of the different species of the genus, it must be conceded that the Eucalyptus is one of -the most imp.rtant fam ily of forest trees known at the present time, and that they should be ex tensively planted wher -ever climatic conditions are favorable to their growth, with the further reminder that the E. ,globulus need not be taken as criterion of the hardiness of the ge nus in low temperatures, since the more alpine species are known to flourish where the E.
globulus has failed. The supposed sanitary value is not confined to one species, but the whole family are possessed of oil-bearing leaves, and that, therefore, further experiment with the hardier species may be profitable. In this con nection it should be re iterated that none of the Eucalyptuses are hardy, and, in fact, all of them are su b- tropical, and many of them really inter-tropical. Hence in experimenting with them in the United States care should be taken to use only those most hardy. Of their value as arresters of miasma there is little doubt, and it would seem proper that agricultural colleges, South, and the gen eral government, should experiment still further with these valuable species.