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Rh last two, only that of Paramatta was utilized; the astronomers Rumker and Dunlop prepared there precious catalogues of stars mostly invisible in our hemisphere. Abandoned after the death of Dunlop, this establishment was suppressed in 1855, and replaced by the observatory of Sydney, that the government of New South Wales caused to be constructed at its own expense to satisfy the complaints of the mariners, who found in these regions no means for regulating their chronometers. Already, two years before, the rapid increase of navigation between Europe and Australia in consequence of the discovery of the gold-mines had led the government of the colony of Victoria to found an observatory at Melbourne, which, under the intelligent direction of Mr. Ellery, quickly took rank among the most active establishments. Melbourne has possessed since 1870 a telescope of colossal dimensions. The tube and the mirror, which is four feet in diameter, weigh together nearly nine tons, and the clockwork movement that regulates this immense machine is of such precision that the wire of the micrometer follows a fixed star for more than an hour. As a precautionary measure, two four-feet mirrors were sent from London instead of one; unfortunately, they were both injured in the passage, it was necessary to repolish them, and, in spite of the impatience and bad humor of the inhabitants of Melbourne, all the results promised from this great telescope have not yet been attained. Instruments of this kind are so much the more delicate as their dimensions are increased, and they demand long practice before being used with success. At present the greater part of the work of the Melbourne establishment is carried on with the ordinary implements of observatories. Mr. Ellery arranged with the astronomers at Sydney and at the Cape for undertaking a grand review of the southern heavens, which were divided into zones, and the three stations shared the systematic exploration. A large portion of these observations has been already published.

The rapid picture we have sketched will give an idea of the extraordinary flight practical astronomy has taken not only on the soil of the British Isles, but upon every point of the globe where the Anglo-Saxon race has planted its colonies. The necessities of navigation have been the prominent motive for the creation of some of the most important English observatories; but the volunteers in science have also done no inconsiderable portion of the common work. The landed aristocracy, the higher branches of trade, the arts and manufactures, hold the honor of being united with the professional men of science, or at least of coöperating in their labors, by an enlightened munificence. Can a better use be made of fortune or leisure? It has been said concerning the organization of the Greenwich Observatory that the essentially practical and utilitarian spirit of the English is manifested also in science, since all the labor in Greenwich is directed toward a special purpose, the incessant improvement of that portion of astronomy that renders so great service to navigation. However,