WALLIS (Dr. John)

, an eminent English mathematician, was the son of a clergyman, and born at Ashford in Kent, Nov. 23. 1616. After being instructed, at different schools, in grammar learning, in Latin, Greek, and Hebrew, with the rudiments of logic, music, and the French language, he was placed in Emanuel college, Cambridge. About 1640 he entered into orders, and was chosen fellow of Queen's college. He kept his fellowship till it was vacated by his marriage, but quitted his college to be chaplain to Sir Richard Darley; after a year spent in this situation, he spent two more as chaplain to lady Vere. While he lived in this family, he cultivated the art of deciphering, which proved very useful to him on several occasions: he met with rewards and preferment from the government at home for deciphering letters for them; and it is said, that the elector of Brandenburg sent him a gold chain and medal, for explaining for him some letters written in ciphers.

In 1643 he published Truth Tryed, or Animadversions on lord Brooke's treatise, called The Nature of Truth &c; styling himself “a minister in London,” probably of St. Gabriel Fenchurch, the sequestration of which had been granted to him.—In 1644 he was chosen one of the scribes or secretaries to the assembly of divines at Westminster.

Academical studies being much interrupted by the civil wars in both the universities, many learned men from them resorted to London, and formed assemblies there. Wallis belonged to one of these, the members of which met once a week, to discourse on philosophical matters; and this society was the rise and beginning of that which was afterwards incorporated by the name of the Royal Society, of which Wallis was one of the most early members.

The Savilian professor of geometry at Oxford being ejected by the parliamentary visitors, in 1649, Wallis was appointed to succeed him, and he opened his lec. tures there the same year. In 1650 he published some Animadversions on a book of Mr. Baxter's, intitled, “Aphorisms of Justisication and the Covenant.” And in 1653, in Latin, a Grammar of the English tongue, for the use of foreigners; to which was added, a tract De Loquela seu Sonorum formatione, &c, in which he considers philosophically, the formation of all sounds used in articulate speech, and shews how the organs being put into certain positions, and the breath pushed out from the lungs, the person will thus be made to speak, whether he hear himself or not. Pursuing these reflections, he was led to think it possible, that a deaf person might be taught to speak, by being directed so to apply the organs of speech, as the sound of each letter required, which children learn by imitation and srequent attempts, rather than by art. He made a trial or two with success; and particularly upon one Popham, which involved him in a dispute with Dr. Holder, of which some account has already been given in the life of that gentleman. |

In 1654 he took the degree of Doctor in Divinity; and the year after became engaged in a long controversy with Mr. Hobbes. This philosopher having, in 1655, printed his treatise De Corpore Philosophico, Dr. Wallis the same year wrote a confutation of it in Latin, under the title of Elenchus Geometriæ Hobbianæ; which so provoked Hobbes, that in 1656 he published it in English, with the addition of what he called, “Six Lessons to the Professors of Mathematics in Oxford.” Upon this Dr. Wallis wrote an answer in English, intitled, “Due Correction for Mr. Hobbes; or School discipline for not saying his Lessons right,” 1656: to which Mr. Hobbes replied in a pamphlet called “*s*t*i*g*m*a*i, &c, or Marks of the absurd Geometry, Rural Language, Scottish Church politics, and Barbarisms, of John Wallis, 1657.” This was immediately rejoined to by Dr. Wallis, in Hobbiani Puncti Dispunctio, 1657. And here this controversy seems to have ended, at this time: but in 1661 Mr. Hobbes printed Examinatio & Emendatio Mathematicorum Hodiernorum in sex Dialogis; which occasioned Dr. Wallis to publish the next year, Hobbius Hcautontimorumenos, addressed to Mr. Boyle.

In 1657 he collected and published his mathematical works, in two parts, entitled, Mathesis Universalis, in 4to; and in 1658, Commercium Epistolicum de Quæstionibus quibusdam Mathematicis nuper habitum, in 4to; which was a collection of letters written by many learned men, as Lord Brounker, Sir Kenelm Digby, Fermat, Schooten, Wallis, and others.

He was this year chosen Custos Archivorum of the university. Upon this occasion Mr. Stubbe, who, on account of his friend Mr. Hobbes, had before waged war against Wallis, published a pamphlet, intitled, “The Savilian Professor's Case Stated,” 1658. Dr. Wallis replied to this; and Mr. Stubbe republished his case, with enlargements, and a vindication against the exceptions of Dr. Wallis.

Upon the Restoration he met with great respect; the king thinking favourably of him on account of some services he had done both to himself and his father Charles the first. He was therefore confirmed in his places, also admitted one of the king's chaplains in ordinary, and appointed one of the divines empowered to revise the book of Common Prayer. He complied with the terms of the act of uniformity, and continued a steady conformist till his death. He was a very useful member of the Royal Society; and kept up a literary correspondence with many learned men. In 1670 he published his Mechanica; sive de Motu, 4to. In 1676 he gave an edition of Archimedis Syracusani Arenarius & Dimensio Circuli; and in 1682 he published from the manuscripts, Claudii Ptolomæi Opus Harmonicum, in Greek, with a Latin version and notes; to which he afterwards added, Appendix de veterum Harmonica ad hodiernam comparata, &c. In 1685 he published some theological pieces; and, about 1690, was engaged in a dispute with the Unitarians; also, in 1692, in another dispute about the Sabbath. Indeed his books upon subjects of divinity are very numerous, but nothing near so important as his mathematical works.

In 1685 he published his History and Practice of Algebra, in folio; a work that is full of learned and useful matter. Besides the works above mentioned, he published many others, particularly his Arithmetic of Infinites, a book of genius and good invention, and perhaps almost his only work that is so, for he was much more distinguished for his industry and judgment, than for his genius. Also a multitude of papers in the Philos. Trans. in almost every volume, from the 1st to the 25th volume. In 1697, the curators of the University press at Oxford thought it for the honour of the university to collect the doctor's mathematical works, which had been printed separately, some in Latin, some in English, and published them all together in the Latin tongue, in 3 vols folio, 1699.

Dr. Wallis died at Oxford the 28th of October 1703, in the 88th year of his age, leaving behind him one son and two daughters. We are told that he was of a vigorous constitution, and of a mind which was strong, calm, serene, and not easily ruffled or discomposed. He speaks of himself, in his letter to Mr. Smith, in a strain which shews him to have been a very cautious and prudent man, whatever his secret opinions and attachments might be: he concludes, “It hath been my endeavour all along to act by moderate principles, being willing, whatever side was uppermost, to promote any good design, for the true interest of religion, of learning, and of the public good.”