Dictionary of National Biography, 1885-1900/Craig, John (d.1620)
CRAIG, JOHN, M.D. (d. 1620), physician, third son of Sir Thomas Craig [q. v.], the eminent lawyer, was born in Scotland, graduated M.D. at Basle, settled in his native country, and became first physician to James VI, whom he accompanied to this country on that monarch's accession to the throne of England as James I. In 1604 he was admitted a member of the College of Physicians of London. He was incorporated M.D. at Oxford 30 Aug. 1605; was named an elect of the College of Physicians on 11 Dec. the same year; was consiliarius in 1609 and 1617; and died before 10 April 1620, when Dr. Argent was chosen an elect in his place.
He was the author of 'Capnuraniae seu Comet, in Aethera Sublimatio,' a manuscript addressed to his friend Tycho Brahe. Some of his letters to that famous astronomer are printed in Rudolf August Nolten's 'Commercium litterarium clarorum virorum,' 2 vols. Brunswick, 1737-8.
Craig is generally believed to have been the person who gave John Napier of Merchiston the first hint which led to his great discovery of logarithms. Wood states that 'one Dr. Craig . . . coming out of Denmark into his own country called upon John Neper, baron of Murcheston, near Edinburgh, and told him, among other discourses, of a new invention in Denmark (by Logomontanus, as 'tis said) to save the tedious multiplication and division in astronomical calculations. Neper being solicitous to know farther of him concerning this matter, he could give no other account of it than that it was by proportionable numbers. Which hint Neper taking he desired him at his return to call upon him again. Craig, after some weeks had passed, did so, and Neper then shew'd him a rude draft that he called "Canon mirabilis Logarithmorum,"' which, with some alterations, appeared in 1614. There seems, however, to be no foundation in fact for this oft-repeated story. It is a remarkable circumstance, not generally known, that Napier himself informed Tycho Brahe of his discovery twenty years before it was made public.
His son, James Craig, M.D., became a fellow of the College of Physicians, and physician to James I and to his successor Charles I, both before and subsequently to his accession to the throne. He died in January 1614-5, and was buried in the church of St. Martin-in-the-Fields. Craig attended James I in his last illness, and gave great offence at court by giving free expression to his opinion that his royal patient had been poisoned.
[Wood's Athenæ Oxon. (Bliss) ii. 491; Fasti, i. 310; Sloane MS. 2149. p. 83; Mark Napier's Memoirs of John Napier, pp. 361-6; Munk's Coll. of Phys. (1873). i. 118, 170; Burnet's Own Time (1823), i. 20 ; Gardiner's Hist. of England, v. 312.]