aperture of 7.8 inches (surpassing that of any refractor then in England, Phil. Trans. cxix. 33), and was willing with some further improvements to attempt one of 2 feet. A committee appointed by the Royal Society in 1831 to report upon the practicability of this daring scheme, advised a preliminary trial upon a smaller scale, and a ‘fluid-lens’ telescope of 8 inches aperture and the extremely short focal length of 83/4 feet (one of the leading advantages of the new principle) was in 1832 executed by Dollond from Barlow's designs. The success, however, of this essay (described Phil. Trans. cxxiii. 1) was not sufficient to warrant the prosecution of the larger design (see the reports of Herschel, Airy, and Smyth, in Proc. R. Soc. iii. 245–53). The ‘Barlow lens’ now in use for increasing the power of any eye-piece is a negative achromatic combination of flint and crown glass, suggested by Barlow, applied by Dollond in 1833 (Phil. Trans. cxxiv. 199), and first employed by Dawes in the measurement of minute double stars (Month. Not. x. 176).
Barlow was much occupied with experiments designed to afford practical data for steam locomotion. He sat on railway commissions in 1836, 1839, 1842, and 1845; and two reports addressed by him in 1835 to the directors of the London and Birmingham Company on the best forms of rails, chairs, fastenings, &c., were regarded as of the highest authority both abroad and in this country. He resigned his post in the Woolwich Academy in 1847, his public services being recognised by the continuance of full pay. His active life was now closed, but he retained the powers of his mind and the cheerfulness of his disposition until his death, 1 March 1862, at the age of 86.
Barlow was elected a fellow of the Royal Society in 1823, and in 1825 received the Copley medal for his discoveries in magnetism. Somewhat later he was admitted to the Astronomical Society, and sat on the committee for the improvement of the ‘Nautical Almanac’ in 1829–30, and on the council in 1831. He was besides a corresponding member of the Paris, St. Petersburg, and other foreign academies.
In addition to the works already mentioned he wrote for Rees's ‘Encyclopædia’ most of the mathematical articles from the letter H downwards, and contributed to the ‘Encyclopædia Metropolitana’ the articles Geometry, Theory of Numbers, Mechanics, Hydrodynamics, Pneumatics, Optics, Astronomy, Magnetism, Electro-Magnetism, as well as the bulky volume on Manufactures. A report by him on the ‘Strength of Materials’ was presented to the British Association in 1833 (Reports, ii. 93). A list of his contributions to scientific periodicals, forty-nine in number, many of them reprinted abroad, will be found in the Royal Society's ‘Catalogue of Scientific Papers’ (8 vols. 8vo, 1867–79).
[Month. Not. R. Astr. Soc. xxiii. 127; Minutes of Proceedings of Inst. Civ. Engineers, xxii. 615, 1862–3; Proc. R. Soc. xii. xxxiii.]
BARLOW, RUDESIND (1585–1656), Benedictine monk, elder brother of the Benedictine, Edward Barlow [q. v.], became superior of St. Gregory's at Douay. Weldon relates that Barlow was looked upon as one of the first divines and canonists of his age; and that 'he exerted the force of his pen against Dr. Richard Smith (who governed the catholics of England under the title of Chalcedon), and succeeded in forcing him to desist from his attempts and pretended jurisdiction of ordinary of Great Britain.' Barlow died at Douay 19 Sept. 1656. Weldon adds that 'after the death of this renowned monk, a bishop sent to the fathers of Douay to offer them an establishment if they would but make him a present of the said father's writings. But in vain they were sought for, for they were destroyed by an enemy.'
[Oliver's Catholic Collections relating to Cornwall, &c., 474, 477, 506; Weldon's Chronological Notes; MS. Burney, 368, f. 100b.]
BARLOW, THOMAS (1607–1691), bishop of Lincoln, was descended from an ancient family seated at Barlow Moor near Manchester. His father, Richard Barlow, resided at Long-gill in the parish of Orton, Westmoreland, where the future bishop was born in 1607 (Barlow's Genuine Remains, p. 182). He was educated at the grammar school at Appleby, under Mr. W. Pickering. In his seventeenth year he entered Queen's College, Oxford, as a servitor, rising to be a tabarder, taking his degree of B.A. in 1630, and M.A. in 1633, in which year he was elected fellow of his college. In 1635 he was appointed metaphysical reader to the university, in which capacity he delivered lectures which were more than once published under the title 'Exercitationes aliquot Metaphysicae de Deo.' His father dying in 1637, Barlow printed a small volume of elegies in his honour, written by himself and other members of his college, entitled 'Pietas in Patrem.' Barlow was regarded as a master of casuistry, logic, and philosophy, in which subjects he had as his pupil the celebrated independent, John Owen, who, as dean of
