[William Clark, Professor of Anatomy in the University of Cambridge.] Autograph Letter Signed ['Wm. Clark. M.D.'], a glowing reference praising C. J. Johnstone of Caius College, with whom he has collaborated on dissections.

1p, 4to. On bifolium. In good condition, lightly aged. Addressed on reverse of second leaf, with two postmarks and seal in black wax, to 'C. J. Johnstone Esqre | M. B – | 53 Tavistock Square | London'. Twenty-two lines of neatly-written text. He is pleased that Johnstone has declared himself 'a candidate for the vacant office of Lecturer in Chemistry at St. Bartholomew's hospital', and assures him that he has his 'warmest wishes' for his success. He considers that Johnstone has been 'very assiduous and successful in the cultivation of those branches of medical science' in which he has come under Clark's observation, 'not only in the public examinations, but in our numerous dissections together'. 'Others will speak to the ability with which you have filled the office of public classical lecturer in your own College: & to your scientific knowledge as a Chemist.' He suggests that Johnstone use the letter in his 'canvass' for 'any office you may think it right to undertake', 'as the expression of my belief that you will discharge, with distinction to yourself & utility to the Institution to which you may be attached'. Ends: 'As far as I know, you are rather likely to retire from too much diffidence of your powers, than to put yourself forward without full warrant.' The London Medical Gazette reports death in 1838 of Johnstone, 'Physician to the Foundling, Fellow of Caius College'. Clark was the son-in-law of George III's doctor Robert Darling Willis (1760-1821). From the distinguished autograph collection of the psychiatrist Richard Alfred Hunter (1923-1981), whose collection of 7000 works relating to psychiatry is now in Cambridge University Library. Hunter and his mother Ida Macalpine had a particular interest in the illness of King George III, and their book 'George III and the Mad Business' (1969) suggested the diagnosis of porphyria popularised by Alan Bennett in his play 'The Madness of George III'.