CONDUITT, John (1688-1737), of Cranbury Park, Hants.

Published in The History of Parliament: the House of Commons 1715-1754, ed. R. Sedgwick, 1970
Available from Boydell and Brewer



26 June 1721 - 3 Apr. 1735
3 Apr. 1735 - 23 May 1737

Family and Education

bap. 8 Mar. 1688, s. of Leonard Conduitt of St. Paul’s, Covent Garden, London by his w. Sarah. educ. Westminster (K.S.) 1701; Trinity, Camb. 1705. m. 26 Aug. 1717, Catherine, da. of Robert Barton of Brigstock, Northants., niece and coh. of Sir Isaac Newton, M.P., 1da.

Offices Held

Master of the mint 1727-d.


In 1717 John Conduitt married Newton’s niece, Catherine Barton, a rich woman eight years older than himself. She had been the reputed mistress of her uncle’s patron, Charles Montagu, Earl of Halifax, who had died in 1715, making a large bequest to her in his will,

as a token of the sincere love, affection, and esteem I have long had for her person, and as a small recompense for the pleasure and happiness I have had in her conversation.1

Having bought a Hampshire estate in 1720, Conduitt was returned in 1721 for Whitchurch in that county, with the support of his friend, John Wallop, Lord Lymington, on the understanding that he was to vacate the seat when Lymington’s infant son, John, came of age.2

In Parliament Conduitt supported the Government, making his first recorded speech on Lord Chancellor Macclesfield’s impeachment (18 Mar. 1725), and speaking against an opposition motion for an account of a recent vote of credit (21 Feb. 1727). On Newton’s death in March 1727, Conduitt succeeded him as master of the mint, the duties of which he had been performing for him since 1722. In 1730 he wrote an able pamphlet on ‘the present state of our gold and silver coins’, which was posthumously published. He also wrote a memorial sketch of Newton and collected materials for a biography of him. He became a fairly frequent government speaker, notably in 1733, when he defended the commissaries sent to Spain to negotiate over the losses suffered by British merchants (13 Feb.); put up a scheme, which was approved, for demonetizing broad-pieces, hammer-struck gold coins worth 23s. (19 Feb.); opposed a petition from Rhode Island asking to be heard by their agent against the sugar colonies relief bill (8 Mar.); and supported the address to the King on the Princess Royal’s marriage (8 May). In the next session he spoke against the repeal of the Septennial Act.

In 1734 Conduitt was re-elected at Whitchurch, but chose to sit for Southampton, where he was awarded the seat after a double return. He introduced a bill to repeal an Act of James I against conjuration and witchcraft (22 Jan. 1736), which became law. His last recorded speech was in favour of the universities on the mortmain bill (5 Apr. 1736).3 On his death, 23 May 1737, he was buried at the right hand of Newton in Westminster Abbey, in which his wife was also buried in 1739. In 1740 their only child, a daughter, with £60,000,4 married Lymington’s son and heir, thus uniting the Conduitt-Wallop interests at Whitchurch and becoming the ancestress of the earls of Portsmouth. She figures in Hogarth’s picture of a children’s performance of Dryden’s Conquest of Mexico at her father’s house in 1732.5

Ref Volumes: 1715-1754

Author: Paula Watson


  • 1. A. de Morgan, Newton, 5658.
  • 2. See WHITCHURCH.
  • 3. HMC Egmont Diary, i. 331-2, 371; ii. 55, 255; Stuart mss 160/1; Craig, The Mint, 240; Harley Diary, 22 Jan. 1736.
  • 4. Gent. Mag. 1740, p. 357.
  • 5. Reproduced in Lord Ilchester, Lord Hervey and his Friends.