Thomas Desaguliers

Lieutenant-General Thomas Desaguliers (5 January 1721 – 1 March 1780) was a British Army general and a Colonel Commandant of the Royal Artillery.

Early life Desaguliers was born 5 January 1721, the youngest son of Dr. John Theophilus Desaguliers. He was the grandson of Jean Desaguliers who, as Protestant pastor of Aytré, near La Rochelle, was exiled in 1682 prior to the revocation of the edict of Nantes. Jean was ordained in the Anglican Church, but served briefly as lecteur at the French chapel in Swallow Street, London.

As a young man Thomas Desaguliers was a Freemason who accompanied his father to masonic meetings and is mentioned in the 1738 edition of the Constitutions of the Freemasons. He was promoted to major-general on 25 May 1772, and lieutenant-general on 29 September 1777.

In recognition of his scientific work Desaguliers was elected a fellow of the Royal Society on 24 February 1780, just before his death; he was the first officer of Royal Artillery who won that distinction.

Personal life On 18 March 1745, Desaguliers married Mary Blackwood (1727–1749) at St George's Chapel, Mayfair. She was the daughter of John Blackwood, art dealer, of Crayford, Kent, and a granddaughter of Admiral Sir Cloudsley Shovell. There is a posthumous portrait of Mary by William Hogarth. Together, they had three children before her death at the age of 23:

Mary Catherine Desaguliers (1747–1814), who married Thomas Cartwright of Aynho, Northamptonshire. After his death, she married Sir Stephen Cotterell, Master of the Ceremonies to the King. She was executrix of her father's will. Anne Desaguliers (1748–1801), who married Robert Shuttleworth of Gawthorpe Hall, Lancashire, son of James Shuttleworth. Frederick Desaguliers (1749–1777), who joined the Royal Artillery as a cadet in 1762; he died a Second Lieutenant in 1777 at the Battle of Princeton during the American Revolutionary War.

Desaguliers never remarried after the early death of his wife. He had an estate, Graces near Little Baddow, Essex, as well as a London home. He demonstrated artillery to the Royal Family, was equerry to King George III and accompanied the monarch on morning horse rides. Desaguliers died unexpectedly on 1 March 1780. He was attended at Woolwich by the King's physician John Hunter (who had tended his wounds at Belle Isle) but succumbed to a ruptured spleen. He was buried alongside his wife at Crayford, where the grave still exists at St Paulinus church.

There is no known portrait of Thomas Desaguliers.

Descendants Through his eldest daughter Mary, he is the ancestor of mathematician Dame Mary Lucy Cartwright.

Through his second daughter Anne, he was a great-grandfather of Janet Shuttleworth, who married the politician and philanthropist Sir James Kay (later Kay-Shuttleworth). A descendant, the present Lord Shuttleworth, is Lord Lieutenant of Lancashire.