Page:History of the Royal Astronomical Society (1923).djvu/75

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.

1830-40] ROYAL ASTRONOMICAL SOCIETY 57 and Remarks for the year 1822,* a perfect ephemeris except that it does not include the sun and the moon. As the object was merely to show what an ephemeris ought to contain, the design was taken from Schumacher's Hulfstafeln for 1820 and 1821, and much of the contents are borrowed from various sources ; e.g., the list of occupations from Zach's Correspondence astronomique (computed for Florence), and the places of the planets from Schumacher's Ephemerides. Shortly afterwards Baily followed this up by publishing Remarks on the present defective state of the " Nautical Almanac." London, 1822, 72 pp. ; dated May 7. In this essay Baily first refers to some remarks he had made in the introduction to his recently published Tables, owing to some of these differing from those of a similar kind in the Nautical Almanac. These comments had called forth an anonymous " Reply to Mr. Baily 's Remarks " in the Journal of the Royal Institution.^ Baily reprints the whole of this reply and then answers it point by point. He goes through the four foreign ephemerides and enumerates the articles in them which are not in the Nautical Almanac. These were but few and unimportant, so far as the Berlin Jahrbuch and the Connaissance des Temps went, but the case was very different with the Coimbra and Milan ephemerides, particularly with the former, which Baily pronounced, on the whole, the best pattern for a work of this kind. His preference of it seems to be mainly due to the innovation of all computations being made with reference to mean solar time instead of apparent time. The Milan ephemeris was specially praised for containing a list of the visible occultations of all stars whose places were given in any catalogue. Baily also pointed out that the Bureau des Longitudes, established in 1796, more than eighty years after the British one, did not contain any useless members, nor " learned professors, who lived upwards of fifty miles from the place of meeting and consequently seldom attend the Board." Simultaneously with Baily's pamphlet appeared one by South : Practical Observations on the Nautical Almanac, 64 pp., dated 1822 April 15. He laid particular stress on showing that the Nautical Almanac had always contained information which was only of use to astronomers, and that there was therefore good reason for extending the items given. He compared observations of eclipses of Jupiter's satellites by Beaufoy and himself with the Nautical Almanac and the Connaissance des Temps, and showed that the data in the latter agree very much better with the observations

  • ii pp. Preface, xxx. pp. Explanation, 72 pp. Tables; chart of the

Pleiades. t Obviously written by Young himself, as Baily also hints.