prognosticated gangrene and probably death. The friends of the wounded man appealed to Sir Kenelm, who generously consented to do his best. He told the attendants to bring him a rag on which was some of the sufferer's blood. They brought the garter which had been used as a bandage and which was still thick with blood. He soaked this in a basin of water in which he had dissolved a handful of his sympathetic powder. An hour later the patient said he felt an agreeable coolness. The fever and pain rapidly abated, and in a few days the cure was complete. It was reported that the Duke of Buckingham testified to the genuineness of the cure and that the king had taken a keen interest in the treatment.
Digby asserted that the secret of the powder was imparted to him by a Carmelite monk whom he met at Florence. His laboratory assistant, George Hartman, published a "Book of Chymicall Secrets," in 1682, after Sir Kenelm's death, and therein explained that the Powder of Sympathy, which was then made by himself (Hartman), and "sold by a bookseller in Cornhill named Brookes" was prepared "by dissolving good English vitriol in as little warm water as will suffice, filter, evaporate, and set aside until fair, large, green crystals are formed. Spread these in the sun until they whiten. Then crush them coarsely and again dry in the sun." Other recipes say it should be dried in the sun gently (a French formula says "amoureusement") for 365 days.
Sir Kenelm's scientific explanation of the action of his sympathetic powder is on the same lines as the others I have quoted. Briefly it was that the rays of the sun extracted from the blood and the vitriol associated with it the spirit of each in minute atoms. At the same time the inflamed wound was exhaling hot
