by G. S. McIntyre
© Oxford University Press 2004 All rights reserved
Brouncker, William, second Viscount Brouncker of Lyons (1620-1684), mathematician and first president of the Royal Society of London, was born at Castle Lyons, co. Dublin in 1620, probably in April, the eldest son of Sir William Brouncker (1585-1645), gentleman of the privy chamber to Charles I and vice-chamberlain to Charles, prince of Wales, and his wife, Winifred (d. 1649), daughter of Sir William Leigh of Newnham. In 1639 the elder Sir William had been commissary general of the musters against the Scots; he was made doctor of civil law at Oxford on 1 November 1642. He received a grant of the monastery of Clonnis and was created Baron Brouncker of Newcastle and Viscount Brouncker of Lyons on 12 September 1645. He died in November 1645 at Wadham College, Oxford, and was buried on 20 November in Christ Church Cathedral. His wife died in July 1649 and was buried in London on 10 August 1649. The younger Brouncker succeeded to his father's titles in 1645.
Brouncker was sent to Oxford University at the age of sixteen and graduated MD on 23 February 1647. There is no indication that he practised medicine, but he avoided the turbulent politics of his day by devoting himself to the study of mathematics. In 1653 he published a translation and critique of Descartes's Musicae compendium under the pseudonym 'a person of honour', where he proposed to divide the diapason into seventeen equal semitones. In 1657 he started corresponding with fellow mathematician John Wallis, and his discoveries were later published as part of Wallis's work. His most important contribution concerned the quadrature of the circle: Brouncker was the first to express the ratio of the area of a circle to the circumscribed square as an infinite continued fraction. As a mathematician, he enjoyed a good reputation for his abilities--Bishop Burnet, for one, refers to him as a 'profound mathematician' (Burnet's History, 1.131). That reputation and his association with Wallis drew Brouncker into the philosophical discussions at Gresham College in the late 1650s, informal gatherings which would eventually grow into the Royal Society of London.
In 1660 Brouncker surfaced as a loyal royalist. In April he signed the 'remarkable declaration' in favour of General Monk and was member of parliament for Westbury, Wiltshire, in the convention parliament of that year. As a reward for his loyalty, on 18 April 1662 Brouncker was appointed chancellor to Queen Catherine and keeper of her great seal. In August 1662 he commissioned and helped design a new yacht for the king. For many years afterwards his relationship with Charles II was cordial, and it was not uncommon for Brouncker to spend time discussing scientific questions with him, often in the company of the diarist John Evelyn or fellow courtier Sir Robert Moray.
The Royal Society of London was incorporated under royal charter, first on 15 July 1662 and again on 15 April 1663. At the time of the second charter Charles II nominated Brouncker as the society's first president, a post he held from 22 April 1663 until 30 November 1677. In that time he continued his interest in mathematics and attempted 'to prove Huygen's assertion of the isochronicity of the cycloidal pendulum' (Whiteside, 157). He also continued his interest in the study of music, and often held musical meetings at his house. In his day he was not known for his experimental research, although he published the results of a series of simple experiments on the recoiling of guns and on the increase in the weight of metals with the application of heat. He was, however, a good administrator: he rarely missed the meetings and regularly paid his dues. Outside the society he was a tireless advocate for the new experimental philosophy. He tried--unsuccessfully--to use his influence at court either to establish a permanent home for the society when it was displaced from Gresham College by the great fire of 1666 or to obtain a grant from the king to cover the society's expenses. As interest in the society waned in the early 1670s many felt that it was time for a change; when it became clear that he would not be re-elected, Brouncker resigned, to be succeeded by Sir Joseph Williamson.
During his presidency Brouncker was also pursuing an active career in the civil service. On 12 November 1664 he was appointed a commissioner of the Admiralty, and it was at this point that he began his long personal and professional relationship with Samuel Pepys. After their first meeting, Pepys described him as a 'modest civil person ... wholly ignorant in the business of the Navy as possible, but I hope to make a friend of him, being a worthy man' (Pepys, 5.341). It would seem that Brouncker performed his duties well: from December 1666 to December 1679 he was an assistant comptroller to the treasurer of the Admiralty. After a brief lapse in favour he was reappointed to this post in 1681. He also served as president of Gresham College from 1664 to 1667, and as master of the royal hospital of St Katharine by the Tower from 21 November 1681, after a long battle with judge Sir Robert Atkyns for the post was resolved in court.
Brouncker never married and had no children. He had a number of mistresses, most notably the actress Abigail Williams, his long-time companion. Pepys was not fond of her, but some of his dislike can be attributed to a fire which started in her closet in 1673. The fire spread to some thirty houses, including Pepys's own, and destroyed much of his furniture and works of art. Brouncker died in his house on St James's Street, Westminster, on 5 April 1684 and was buried on 14 April 1684 in the choir of the chapel attached to the hospital of St Katharine.
William Brouncker was succeeded by his brother Henry Brouncker, third Viscount Brouncker of Lyons (c.1627-1688), cofferer to Charles II and gentleman of the bedchamber to the duke of York. Henry was created MD on 23 June 1646, took part in the siege of Colchester in 1648, served as the MP for Romney from 1665 to 1668, and was a commissioner of trade and plantation in 1673. According to charges brought against him in the House of Commons in 1668, he ordered the sails of the British fleet to be slackened in the duke of York's name during the battle of Lowestoft in 1664, thereby allowing the Dutch to escape. As a result of the incident he was dismissed from the duke's service and expelled from parliament. He was not well liked, although admired for his skill with chess: Edward, earl of Clarendon, described him as 'a man throughout his whole life notorious for nothing but the highest degree of impudence, stooping to the most infamous offices, and playing chess very well, which preferred him more than the most virtuous qualities could have done' (Clarendon, 2.515). In May 1661 he married Rebecca Rodway, widow of Thomas Jermyn, brother to the earl of St Albans; they had no children, and with his death, on 4 January 1688 at Sheen Abbey, Surrey, the viscountcy and the barony became extinct. He was buried at Richmond, Surrey.
G. S. MCINTYRE
Sources
J. F. Scott and H. Hartley, 'William, Viscount Brouncker, FRS (1620-1684)', Notes and Records of the Royal Society, 15 (1960), 147-56
Pepys, Diary
GEC, Peerage
T. Birch, The history of the Royal Society of London, 4 vols. (1756-7); repr. with introduction by A. R. Hall (1968), vols. 1-3
Bishop Burnet's History of his own time, new edn (1850)
D. T. Whiteside, 'Brouncker's mathematical papers', Notes and Records of the Royal Society, 15 (1960), 157
T. Sprat, History of the Royal Society, ed. J. I. Cope and H. W. Jones (1958)
A. Kippis and others, eds., Biographia Britannica, or, The lives of the most eminent persons who have flourished in Great Britain and Ireland, 2nd edn, 2 (1780), 613-14
Wood, Ath. Oxon.
N. Luttrell, A brief historical relation of state affairs from September 1678 to April 1714, 1 (1857)
M. Hunter, The Royal Society and its fellows, 1660-1700: the morphology of an early scientific institution, 2nd edn (1994)
C. R. Weld, A history of the Royal Society, 2 vols. (1848)
Diary of John Evelyn, ed. W. Bray, 1-2 (1889)
The life of Edward, earl of Clarendon ... written by himself, 3 vols. (1759), vol. 2
J. Dutka, 'Wallis's product, Brouncker's continued fraction, and Leibniz's series', Archive for History of Exact Sciences, 26 (1982), 115-26
C. Jamison, The history of the Royal Hospital of St Katharine by the Tower of London (1952)
The diary of Robert Hooke ... 1672-1680, ed. H. W. Robinson and W. Adams (1935)
The correspondence of Henry Oldenburg, ed. and trans. A. R. Hall and M. B. Hall, 13 vols. (1965-86)
'Brouncker, The Hon. Henry', HoP, Commons
Archives
Hunt. L., proposal 'on the manning of ships in ordinary' | BL, corresp. with Petty relating to naval matters
RS, letters to Royal Society
Likenesses
P. Lely, oils, 1661, RS
P. Lely, oils, c.1674, RS; versions, NPG, Althorp, Northants [see illus.]
oils, c.1675 (Henry Brouncker; after P. Lely), NPG
W. Hollar, etching (after J. Evelyn), NPG; repro. in T. Sprat, History of the Royal Society (1667)
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