NAPIER, JOHN ( 1550-1617). A Scotch mathe matician, born at Merchiston, near Edinburgh. lie was educated at Saint Andrews and probably also abroad. llis natural pugnacity of character often involved him in difficulties with his neigh bors and tenants. In 1594 he published his Plaine Discovery of the Whole Revelation of Saint John (2(1 ed., London. 1611), in which he sought to prove that the Pope was Antichrist. In somewhat the same spirit, ostensibly to defend his country from "the enemies of God and true religion," lie made some secret inventions. includ ing burning-mirrors, a piece of artillery, and a chariot of metal, none of which had any more merit than his theological contributions. Napier's fame rests on his mathematical discoveries, and lie is chiefly known as the inventor of logarithms (q.v.). In his earlier investigations lie seems to have been considering the subject of imaginary roots, and he refers to this as an important algebraic secret. The idea of logarithms seems to have occurred to him as early as 1594, and thenceforward the rest of his life was spent in developing the idea and computing logarithmic tables. He also invented some mechanical de vices for computation known as 'Napier's rods.'
(See CALCULATING MACHINES.) By means of these, multiplication and division can be per formed, and square and cube roots extracted. He was also the inventor of a number of formulas in trigonometry, known as `Napier's circular parts.' (See CIRCULAR PARTS. ) Napier was one of the first English writers to make any valuable contri bution to mathematics, and his discoveries mark an epoch in the history of science. His chief writ ings are: Dc Arte Logistics (written in 1573, published in 1839) ; .1/irifici Logarithmorum Canonis Descriptio (1614 and subsequent edi tions; Eng. trans., 1616 and 1857) ; ]Iirifici Logarithmorum Canonis Constructio (1619; Eng. trans. 1889) ; Rabdologia. sett Numerationis per Libri Duo ( 16171. Consult : Mark Napier, Memoirs of Napier (Edinburgh, 1793) ; Earl of Buchan, Life of Napier (ib.. 1787). A complete edition of Napier's works appeared in Edinburgh in 1839. A bibliography of Napier's works, by Macdonald, may be found in the Eng lish translation of the Logarithmorum Canonis Constructio mentioned above.