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    JEAN DOMINIQUE CASSINI.—In the course of his examination of the older archives of the Paris Observatory, which had been placed at his disposal with unrestricted permission to make extracts for use in his lunar researches, in the first instance by Delaunay and afterward: by Leverrier, Prof. Newcomb discovered that the wide cpread belief that Cassini I. was director of the Observa-tory which is even stated to have been the fact in French histories of astronomy, is an error. The establishment appears to have been assigned for the common use of the Academy of Sciences, and no such office as that of director was known or recognised. Prof. Newcomb Suggests it may have been the celebrity of Cassini which gave rise to the impression that he was director of thr Observatory. Of the astronomical records of that time preserved in the archives a large portion were evidently never intended to be understood or used except by the observers themselves. The note-books have no titles, no indications of the observer or indications of the instruments employed, except in the case of clocks: each observer seems to have had his own instruments, without any reference to or comparison with those of others. In the earlier observations no designations even of occulted stars were attached, so that it was necessary for Prof. Newcomb's investigation to calculate the places of the moon as affected by parallax for the times of observation before the objects could be identified, an operation which, though laborious, was always successful except in the cases of a few small stars. Lalande, in his notice of the work of Cassini I., does not call him director of the Observatory at Paris. Louis XIV., he states, applied to the Pope, Clement IX., for permission for Cassini to pass some years in Paris, where the Academy of Sciences was in course of formation, offering him, through Colbert, 9,000 livres per annum for the period of his residence in France. He arrived at Paris on April 4, 1669, and his reception by the French king was such that he wished to remain permanently in the country. The Pope offered opposition at first, which the king succeeded in overcoming, and Cassini was naturalised, and, as Lalande says, obtained a considerable fortune. He commenced observations at the Paris Observatory in September, 1671.

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