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 passionate, and complete; his mental grasp was close and unrelaxing. He ranks as the founder of modern observational astronomy; nor by the example of his 'solicitous accuracy' alone or chiefly, though this was much. But his discoveries of aberration and nutation first rendered possible exact knowledge of the places of the fixed stars, and thereby of the movements of the other celestial bodies. Moreover, he bequeathed to posterity, in his diligent and faithful record of the state of the heavens in his time, a mass of documentary evidence invaluable for the testing of theory, or the elucidation of change. The publication, for the benefit of his daughter, of his observations, contained in thirteen folio and two quarto volumes, was interrupted by official demands for their possession, followed up by a lawsuit commenced by the crown in 1767, but abandoned in 1776. The Rev. Mr. Peach, Bradley's son-in-law, thereupon offered them to Lord North, to be printed by the Clarendon Press, and after many delays the first of two volumes appeared in 1798, under the editorship of Dr. Hornsby, with the title 'Astronomical Observations made at the Royal Observatory at Greenwich, from the year 1750 to the year 1762;' the second, edited by Dr. Abram Robertson, in 1805. They number about 60,000, and fill close upon 1,000 large folio pages. A sequel to Bradley's work, in the observations of Bliss and Green down to 15 March 1765, was included in the second volume. A catalogue of 387 stars, computed by Mason from Bradley's original manuscripts, and appended to the 'Nautical Almanac' for 1773, formed the basis of a similar work inserted by Hornsby in vol. i. (p. xxxviii); and 1,041 of Bradley's stars, reduced by Pilati, were added to Piazzi's second catalogue (1814). In the hands of Bessel, however, his observations assumed a new value. With extraordinary skill and labour he deduced from them in 1818 a catalogue of 3,222 stars for the epoch 1755, so authentically determined as to afford, by comparison with their later places, a sure criterion of their proper motions. The title of 'Fundamenta Astronomiæ' fitly expressed the importance of this work. More accurate values for precession and refraction were similarly obtained. Bradley's observations of the moon and planets, when reduced by Airy, supplied valuable data for the correction of the theories of those bodies.

Portraits of him are preserved at Oxford (by Hudson), at Shirburn Castle, at Greenwich, and in the rooms of the Royal Society. A dial, erected in 1831 by command of William IV, marks the spot at Kew where he began the observations which led to the discoveries of aberration and nutation. His communications to the Royal Society, besides those already adverted to, were on 'The Longitude of Lisbon and the Fort of New York, from Wanstead and London, determined by Eclipses of the First Satellite of Jupiter' (Phil. Trans. xxxiv. 85); and 'An Account of some Observations made in London by Mr. George Graham, and at Black River in Jamaica by Colin Campbell, Esq., concerning the going of a Clock; in order to determine the Difference between the Lengths of Isochronal Pendulums in those Places' (ib. xxxviii. 302). His 'Directions for using the Common Micrometer' were published by Maskelyne in 1772 (ib. lxii. 46). The originals of Bradley's Greenwich observations having been deposited in the Bodleian, the confused mass of his remaining papers, disinterred by Professor S. P. Rigaud, afforded materials for a large quarto volume, published by him in 1832 at Oxford, with the title 'Miscellaneous Works and Correspondence of James Bradley, D.D., Astronomer-Royal.' It includes, besides the Kew and Wanstead journals, every record of the slightest value in his handwriting, not omitting papers already printed in the 'Philosophical Transactions,' with many letters addressed to him by persons of eminence in England and abroad, and in some cases his replies. The prefixed memoir embodies all that the closest inquiry could gather concerning him. The investigation of his early observations, thus brought to light after nearly a century's oblivion, was made the subject of a prize by the Royal Society of Copenhagen in 1832; whence the publication by Dr. Busch of Königsberg of 'Reduction of the Observations made by Bradley at Kew and Wanstead to determine the Quantities of Aberration and Nutation' (Oxford, 1838).



BRADLEY, RALPH (1717–1788), conveyancing barrister, was a contemporary of [q. v.], who has been called the patriarch of modern conveyancing. Bradley was called to the bar by the society, of Gray's Inn, and practised at Stockton-on-Tees with great success for upwards of half a century, he is said to have managed the concerns of almost the whole county of Durham, and,