Page:Dictionary of National Biography volume 59.djvu/48

  [Ann. de Winton, ap. Ann. Monast. vol. ii., Will. of Malmesbury's Gesta Pontiff. (both Rolls Ser.); Eadmer, Hist. Nov. ed. Migne; A.-S. Chron. App. ed. Plummer; Lanfranc's Epp. ed. Giles; Freeman's Norman Conquest, and Will. Rufus; Willis's Architect. Hist. of Winchester (Archæol. Inst. 1846); Kitchin's Winchester (Hist. Towns ser.).] 

WALKER, ADAM (1731?–1821), author and inventor, born at Patterdale in Westmoreland in 1730 or 1731, was the son of a woollen manufacturer. He was taken from school almost before he could read, but supplied lack of instruction by unremitting study. He borrowed books, built for himself a hut in a secluded spot, and occupied his leisure in constructing models of neighbouring corn mills, paper mills, and fulling mills. His reputation as a student at the age of fifteen procured him the post of usher at Ledsham school in the West Riding of Yorkshire. Three years later he was appointed writing-master and accountant at the free school at Macclesfield, where he studied mathematics. He also made some ventures in trade which were unsuccessful, and lectured on astronomy at Manchester. The success of his lectures encouraged him, after four years at Macclesfield, to set up a seminary at Manchester on his own account. This, however, he gave up a little later for the purpose of travelling as a lecturer in natural philosophy, and, after visiting most of the great towns in Great Britain and Ireland, he met Joseph Priestley [q. v.], who induced him to lecture in the Haymarket in 1778. Meeting with success, he took a house in George Street, Hanover Square, and read lectures every winter to numerous audiences. He was engaged as lecturer by the provost of Eton College, Edward Barnard, whose example was followed by the heads of Westminster, Winchester, and other public schools.

Walker amused his leisure by perfecting various mechanical inventions. Among others he devised engines for raising water, carriages to go by wind and steam, a road mill, a machine for watering land, and a dibbling plough. He also planned the rotatory lights on the Scilly Isles, erected on St. Agnes' Island in 1790 under his personal superintendence. On 29 July 1772 he took out a patent (No. 1020) for an improved harpsichord, called the ‘Cœlestina,’ which was capable of producing continuous tones. On 21 Feb. 1786, by another patent (No. 1533), he introduced a method of thermo-ventilation, on lines formerly proposed by Samuel Sutton, on 16 March 1744 (patent No. 602), with whose ideas, however, Walker was unacquainted. He proposed to ventilate as well as heat a house without expense by means of a kitchen fire. His method, though economically fallacious, was not without ingenuity.

Walker also constructed an ‘eidouranion,’ or transparent orrery, which he used to illustrate his astronomical lectures. These were published in pamphlet form, under the title ‘An Epitome of Astronomy,’ and reached a twenty-sixth edition in 1817. Walker died at Richmond in Surrey on 11 Feb. 1821. A medallion portrait by James Tassie is in the National Portrait Gallery, Edinburgh.

His chief works were: 1. ‘Analysis of Course of Lectures on Natural and Experimental Philosophy,’ 2nd edit. [Manchester, 1771?], 8vo; 12th edit. London, 1802, 8vo. 2. ‘A Philosophical Estimate of the Causes, Effect, and Cure of Unwholesome Air in large Cities’ [London], 1777, 8vo. 3. ‘Ideas suggested on the spot in a late Excursion through Flanders, Germany, France, and Italy,’ London, 1790, 8vo. 4. ‘Remarks made in a Tour from London to the Lakes of Westmoreland and Cumberland,’ London, 1792, 8vo. 5. ‘A System of Familiar Philosophy,’ London, 1799, 8vo; new edit. London, 1802, 2 vols. 4to. He was the author of several articles in the ‘Philosophical Magazine’ and in Young's ‘Annals of Agriculture.’

Walker had three sons—William; Adam John, rector of Bedston in Shropshire; and Deane Franklin—and one daughter, Eliza (d. 1856), who was married to Benjamin Gibson of Gosport, Hampshire.

His eldest son, (1767?–1816), born in 1766 or 1767, assisted his father in his astronomical lectures, and died before him, on 14 March 1816, at the manor-house, Hayes, Middlesex, leaving a widow and children (Gent. Mag. 1816, i. 374).

His youngest son, (1778–1865), born at York on 24 March 1778, after the death of his brother William continued his father's lectures at Eton, Harrow, and Rugby, as well as his popular discourses in London. He died in Upper Tooting, Surrey, on 10 May 1865. By his wife, the daughter of Thomas Normansell, he left three daughters (ib. 1865, ii. 113).

[Gent. Mag. 1821, i. 182; Allibone's Dict. of Engl. Lit.; Woodley's View of the Scilly Isles, 1822, p. 319; Bernan's Hist. and Art of Warming and Ventilating, 1845, ii. 14–16.] 

WALKER, ALEXANDER (1764–1831), brigadier-general, born on 12 May 1764, was the eldest son of William Walker (1737–1771), minister of Collessie in Fife, by his wife Margaret (d. 1810), daughter of