Page:Dictionary of National Biography volume 19.djvu/253

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chiefly valuable for the description, with which it terminated, of the Greenwich instruments and methods; the catalogues of Ptolemy, Ulugh Beigh, Tycho Brahe, the Landgrave of Hesse, and Hevelius followed; finally came the ‘British Catalogue’ of 2,935 stars observed at Greenwich, to which Halley's southern stars were appended. A dedication to George I, by Margaret Flamsteed and James Hodgson (the husband of Flamsteed's niece), was prefixed to the first volume; but Flamsteed's vindication of his conduct was cancelled from the preface, doubtless out of regard to the reputation of Newton and Halley.

The appearance of the ‘Atlas Cœlestis,’ corresponding to the ‘British Catalogue,’ was delayed, owing to difficulties with engravers and lack of funds, until 1729. The figures of the constellations were drawn by Sir James Thornhill. Crosthwait's labours in editing his master's works thus extended over ten years, and involved the sacrifice of his own prospects in life. Yet he never received one farthing. For this signal act of injustice Mrs. Flamsteed was responsible. She showed, nevertheless, an active zeal for her husband's honour, and resisted with spirit and success the outrageous claim made by the government after his death to the possession of his instruments. She died on 29 July 1730, and was buried with him at Burstow.

Flamsteed was in many respects an excellent man—pious and conscientious, patient in suffering, of unimpeachable morality, and rigidly abstemious habits. His wife and servants were devoted to him, living and dead; but his naturally irritable temper, aggravated by disease, could not brook rivalry. He was keenly jealous of his professional reputation. His early reverence for Newton was recorded in the stray note among his observations: ‘I study not for present applause; Mr. Newton's approbation is more to me than the cry of all the ignorant in the world.’ Later he was not ashamed to call him ‘our great pretender,’ and to affect scorn for his ‘speculations about gravity,’ ‘crotchets,’ and ‘conceptions.’ The theory of gravitation he described in 1710 as ‘Kepler's doctrine of magnetical fibres, improved by Sir C. Wren, and prosecuted by Sir I. Newton,’ adding, ‘I think I can lay some claim to a part of it.’ He had certainly, in 1681, spoken of the attraction of the sun as determining the fall towards him of the great comet, but attributed the curve of its path to the resistance of the planetary vortex.

‘Flamsteed,’ Professor De Morgan wrote, ‘was in fact Tycho Brahe with a telescope; there was the same capability of adapting instrumental means, the same sense of the inadequacy of existing tables, the same long-continued perseverance in actual observation’ (Penny Cyclopædia). Nor was he a mere observer piling up data for others to employ, but diligently turned them to account for improving the power of prediction. His solar tables were constructed at the age of twenty-one, published in 1673 with Horrocks's ‘Opera Posthuma,’ and constantly, in subsequent years, amended. The discovery of the importance of the Horroxian lunar theory was due to him; he extended it to include the equations given by Newton in 1702, and he formed thence improved tables published in Lemonnier's ‘Institutions Astronomiques’ in 1746. He remarked the alternately and inversely accelerated and retarded movements of Jupiter and Saturn; determined the elements of the solar rotation, fixing its period at 251/4 days, and formed from diligent observations of sun-spots a theory of the solar constitution similar to that introduced later by Sir William Herschel, viz. ‘that the substance of the sun is terrestrial matter, his light but the liquid menstruum encompassing him’ (Brewster, Newton, ii. 103). He observed Uranus six times as a fixed star, the observation of 13 Dec. 1690 affording the earliest datum for the calculation of its orbit.

Flamsteed's ‘British Catalogue’ is styled by Baily ‘one of the proudest productions of the Royal Observatory at Greenwich.’ Its importance is due to its being the first collection of the kind made with the telescope and clock. Its value was necessarily impaired by defective reduction, and Flamsteed's neglect of Newton's advice to note the state of the barometer and thermometer at the time of his observations rendered it hopeless to attempt to educe from them improved results by modern processes of correction. The catalogue showed besides defects attributable to the absence of the author's final revision. Sir William Herschel detected errors so numerous as to suggest the need of an index to the original observations printed in the second volume of the ‘Historia Cœlestis.’ Miss Herschel undertook the task, and showed, by recomputing the place of each star, that Flamsteed had catalogued 111 stars which he had never observed, and observed 560 which he had not catalogued (Phil. Trans. lxxxvii. 293). Her catalogue of these inedited stars was published by order of the Royal Society in 1798; they were by Baily in 1829 arranged in order of right ascension, and identified (all but seventy) by comparison with later catalogues (Memoirs R. Astr. Soc. iv. 129).

Flamsteed's portrait was painted by Gibson in 1712. An engraving by Vertue was prefixed to the ‘Historia Cœlestis,’ and the