Digby (Sir Kenelm, natural philosopher and courtier, 1603-65) Autograph Letter signed to Robert Sidney, second Earl of Leicester, 1p. with address panel, sm. 4to, London, 21st June 1637, writing to "My good lorde... to congratulate wth. you the happy conclusion of the treaty you have carried and effected wth. so much honor", and hoping to visit Paris in about three weeks time and visit him to "kisse yr. handes", tears where opened repaired, left margin laid down on modern paper for an album, folds, slightly browned.

⁂ Autograph material by Sir Kenelm Digby is extremely scarce.

Digby's premature congratulations to the Earl of Leicester on a putative Anglo-French treaty. Robert Sidney, second Earl of Leicester (1595-1677), diplomat and landowner. In April 1636 Charles I sent Leicester as ambassador-extraordinary to Louis XIII of France, seconding the mission of the ambassador-in-ordinary, Viscount Scudamore, whose negotiations with the French had proved unsuccessful. Despite working hard for a projected Anglo-French agreement, other factors such as intrigues against Cardinal Richelieu, and secret talks with the exiled Marie de Medici, doomed the treaty from the start.

Kenelm Digby, the elder son of Sir Everard Digby (c. 1578-1606), executed for his part in the Gunpowder Plot. Digby was a man of many parts, including, as a courtier (he was a friend of Charles I and was known to Cromwell), poet, traveller, book collector, author and inventor. In 1625 he married the beautiful Venetia Stanley, a childhood friend who he mourned extravagantly when she died in 1633 (Van Dyck made the death-mask for a deathbed portrait); he travelled extensively, fighting a naval action against Venetian galleys off Iskenderun, and living successively in France and Italy. One of Digby's main claims to fame were his chemical experiments, including the renowned Powder of Sympathy, made "... from dried green vitriol, this was a variant of the well-known Paracelsian 'weapon salve' which cured wounds by being applied, not to the patient, but to the offending weapon. Digby had cured his friend James Howell, then the duke of Buckingham's secretary, of a sword-cut in the hand by dissolving some powdered vitriol crystals in water and plunging into the mixture a cloth stained with blood from the wound. The pain in Howell's hand, some yards away, immediately ceased. Many were convinced by Digby's evidence, including Joseph Glanvill, later a Royal Society fellow, and Nathaniel Highmore, a distinguished anatomist and friend of William Harvey. In fact the cure lay in washing and bandaging the wound." - Oxford DNB.