lished ‘Mathematical Lucubrations’ in 1755, and from 1754 onwards communicated to the Royal Society valuable investigations on points connected with the fluxionary calculus. His attempt to substitute for it a purely algebraical method, expounded in book i. of 'Residual Analysis’ (London, 1784) was further prosecuted by Lagrange Book’ ii. never appeared. The remarkable theorem known by Landen‘s name, for expessing a hyperbolic arc in terms of two elliptic arcs, was inserted in the Philosophical Transactions’ for 1775, and specimens of its use were given in the first volume of his ‘Mathematical Memoirs (1780). In a paper on rotary motion laid before the Royal Society on 17 March 1785 he obtained results differing from those of Euler and D'Alembert, and defending them in the second volume of ‘Mathematical Memoirs' prepared for the press during the intervals of a painful disease, and placed in his hands, printed, the day before his death at Milton, near Peterborough, the seat of the Earl Fitzwilliam on 15 Jan. 1790. In the same work he solved the problem of the spinning of a top, and explained Newton's error in calculating the effects of precession.
Landen was elected a fellow of the Royal Society on 16 Jan. 1766, and was a member of the Spalding Society. Though foreigners gave him a high rank among English analysts, he failed to develope and combine his discoveries. He led a retired life, chiefly at Walton in Northamptonshire. Though humane and honourable, he was too dogmatic in society. Besides the works above mentioned, he wrote: 'A Discourse concerning the Residual Analysis' (1758) and ‘Animadversions on Dr. Stewart’s computation of the Sun’s Distance from the Earth’ (1771). Papers by him included in ‘Philosophical Transactions,' vols. xlviii. li. lvii. lx. 1xi. lxvii. lxxv.
[Gent. Mag. vol. lx. pt. i. pp. 90, 191; Phil. Trans. Abidged, x. 469 (Hutton); Hutton's Mathematical Dict. 1815; Montucla's Hist. des Mathématiques; iii. 240; Montferrier's Dict. des Mathématiques; Poggendorff's Biographisch-Literarisches Handwörterbuch: Masres Scriptores Logarithmici, ii, 172; Richelot's Die Landensche Transformation in ihrer Anwendung auf die Entwickelung der eliptischen Functionen, 1868; Watt's Bibl. Brit.]
LANDER, JOHN (1807–1839), African traveller, born in Cornwall in 1807, was brother of Richard Lemon Lander [q. v.], and was by trade a printer. He accompanied his brother Richard without promise of any reward) in his expedition which left England under government auspices in January 1830 to explore the course and termination of the river Niger, and, after discovering the outlet of the river in the Bight of Biafra, returned home in July 1881. His African journal was incorporated with that of his brother in the narrative of the expedition published in 1832. Viscount Goderich, the president of the Royal Geographical Society, procured for Lander a tide-waiter's place in the custom house. Lander died on 6 Nov. 1889 in Wyndham Street, Bryanston Square, at the age of thirty-three, of a malady originally contracted in Africa. He left a widow and three children.
[Tregellas's Cornish Worthies, London, 1884, ii. 202-3; Brit. Mus. Cat. Printed Books; Gent. Mag. new ser. xii. 662.]
LANDER, RICHARD LEMON (1804–1834), African traveller, was born 8 Feb. 1804, at Truro, Cornwall, where his father kept the Fighting Cocks Inn, afterwards known as the Dolphin. His grandfather was a noted wrestler. A contested election for the borough was won on the day of his birth by Colonel Lemon, and suggested his second name. He was the fourth of six children, and is described as a bright little fellow, whose roving propensities gave his friends constant anxiety. He was educated at ‘old Pascoe’s’ in Coombs Lens of his native town, and was a great favourite with the master. At thirteen he went out with s merchant to the West Indies, had an attack of yellow fever at San Domingo returned home in 1818, and afterwards lived as servant in several wealthly families in London, with whom he traveled on the continent. In 1823 he went to the Cape Colony as a private servant to Major Colebrooke royal artillery, afterwards General Sir W. M. G. Colbrooke, C.B. (cf. Colonial List, 1869), then one of the commissioners of colonial inquiry. After traversing the colony with his master, Lander returned home with him in 1824. The discoveries of Lieutensnt Hugh Clapperton [q.v.] and Major Dixon Denham [q.v.] were at the time attracting much attention, and offered his services to Clapperton, refusing better-paid employment in south America. With Clapperton Lander went to Western Africa, and was his devoted attendant duin his second and last expedition into the interior until his death in 1827. Lander then made his way to the coast, reporting Clapperton's death to Denham, who was on a visit to Fernando Po, and by whom the news was sent to England. Lander followed with Clapperton's papers, arriving at Portsmouth in April 1828. To Clapperton's published ‘Journal,’ was added the ‘Journal of Richard Lender from Kano to the Coast,' London, 1829 4to. Lander afterwards published 'Records of Captain Clapperton's last