JONES, WILLIAM (1675?-1749), mathematician

Name: William Jones
Date of birth: 1675?
Date of death: 1749
Spouse: Mary Jones (née Nix)
Child: William Jones
Parent: Elizabeth George (née Rowland)
Parent: John George
Gender: Male
Occupation: mathematician
Area of activity: Science and Mathematics
Author: Robert Thomas Jenkins

Born at Merddyn, Llanfihangel Tre'r Beirdd, Anglesey. His son's biography says that William Jones was born in 1680, but he was born in 1674 or 1675, the same year as Morris Ap Rhisiart Morris, the father of the Morris brothers of Anglesey; the family removed to Tyddyn-bach, Llanbabo, and when the father died the mother went to live at Clymwr in the same parish - hence the Morris family's ' nickname, ' Pabo,' for William Jones. The father was John George; the mother was Elizabeth Rowland, of the family of Bodwigan, Llanddeusant (J. E. Griffith, Pedigrees, 3), and Elizabeth's mother was of the family of Tregaian and therefore, according to Lewis Morris (Add. M.L., p. 190), related to the Morris family's father and mother. He was at school at Llanfechell, and showed such skill as a calculator that his landlord (Bulkeley of Baron Hill) sent him up to London; after a period in a countinghouse there he became instructor on a man-of-war, and attracted the notice of admiral Anson. Tutorships in great families followed; two of his pupils, Thomas Parker (earl of Macclesfield) and Philip Yorke (earl Hardwicke) became Lords Chancellor. Macclesfield afterwards took him as tutor to his son, and Shirburn castle became Jones's home for many years. He lost heavily when his banker failed, but his friendship with the great brought him profitable sinecures. He was married twice: (1) to the widow of the merchant who employed him when he went to London. This might explain how he came by the money which he later lost; and (2) to Mary Nix on 17 April 1731 when he was 56 and she was 25. They had two sons and a daughter. He died in London, 1 July 1749, and was buried in St. Paul's church, Covent Garden on 7 July 1749.

He left his mark on mathematics in several ways. The use of the symbol π to designate the ratio of the circumference of a circle to its diameter first appeared in his book Synopsis Palmarorium Matheseos (1706) and it was he, in his editions of Newton's works who used the dot as the differential sign in the calculus. In one of his papers in the Trans. of the Royal Society he created a rule for compound interest and many mathematicians of the period sought his opinion of their work. He was a friend of Halley's and of Newton's (some of whose works he edited), was F.R.S. in 1712, and became vice-president of the Society.

It will be seen that Jones's career fell outside Wales, and his contacts with Welsh concerns were casual, though none the less interesting. It seems that Richard alone of the Morris family knew him personally, though Lewis in 1749 wrote to him. But in 1747 (Morris Letters, 129), we find Richard suggesting that Jones should propose Lewis for membership of the Royal Society - a service which he had already rendered to Moses Williams (1685 - 1742). When Richard Morris's edition of the Welsh Bible appeared (1746), it included two maps, 'a gift of William Jones, F.R.S., to the Welsh people.' On the death of Moses Williams, his widow sold his books and manuscripts to his friend William Jones, and Richard Morris took on the cataloguing of the manuscripts.

In his will he left his library of some 15,000 works and over 50,000 pages of manuscripts, including hundreds of pages refering to those whom he knew and several of Newton's MSS. to the 3rd Earl Macclesfield, who refused Morris further access to them. The earl talked of giving them to the British Museum, but many of these remained in the earl's home, Shirburn Castle. Angharad Llwyd tells us that she too offered to complete the catalogue but was told that the manuscripts ' were not worth the trouble.' But in 1899 many were bought by Sir John Williams and catalogued by J. Gwenogvryn Evans - they are today (with Richard Morris's notes and indexes) in the National Library of Wales.

William Jones's youngest child

Sir WILLIAM JONES (1746 - 1794), philologist and an authority on Hindu law

There is a biography (Memoirs of Sir W. Jones, 1804) by lord Teignmouth, and a full article in D.N.B. He was born 28 September 1746, married Anna, sister of dean W. D. Shipley, and died 27 April 1794 at Calcutta. He spoke no Welsh, and though he had a slight reading knowledge of it he never studied it systematically - a witty British ambassador in Paris presented him to the French king as ' a man who knew every language except his own.' He was a member of the Cymmrodorion in 1778, and a letter written by Richard Morris junior from India in 1785 (Add. M.L., p. 781) reveals that he was discussing with William Jones the project of publishing Lewis Morris's Celtic Remains; but Angharad Llwyd quotes from a letter of his (1790) to Morris, which avers that 'though, as a Cymmrodor, he was keenly interested in the antiquities and literature of Wales, yet he had not a minute to spare for them.'



Published date: 1959

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