# Dictionary of National Biography, 1885-1900/Duncan, Mark

​DUNCAN, MARK (1570?–1640), regent of the university of Saumur, son of Thomas Duncan of Maxpoffle, Roxburghshire, by Janet, daughter of Patrick Oliphant of Sowdoun in the same county, is supposed to have been born about 1570, and to have been educated partly in Scotland and partly on the continent. He certainly took the degree of M.D., but at what university is not known. From Duplessis-Mornay, appointed governor of Saumur by Henry IV in 1589, he received the post of professor of philosophy in the university of Saumur, of which he subsequently became regent. He is said to have been versed in mathematics and theology, as well as in philosophy, and to have acquired such a reputation for medical skill that James I offered him the post of physician in ordinary at the English court, and even forwarded to him the necessary patent; but to have declined the royal invitation out of regard to his wife (a French lady), who was reluctant to leave her native land. He published in 1612 'Institutiones Logicæ,' to which Burgersdijck, in the preface to his own 'Institutiones Logicæ' (2nd ed. 1634), acknowledged himself much indebted, and which indeed seems to have served as a model to the latter work; also (anon.) in 1634, 'Discours de la Possession des Religieuses Ursulines de Loudun,' an investigation of the supposed cases of demoniacal possession among the Ursuline nuns of Loudun. The phenomena had been attributed to the sorcery of Urbain Grandier, curé and canon of Loudun, who had been burned at the stake in consequence. Duncan explained them, at much risk to himself, as the result of melancholy. He is said to have been shielded from the vengeance of the clergy only by the influence of the wife of the Maréchal de Brézé, then governor of Saumur. This work elicited an answer in the shape of a 'Traité de la Mélancholie' by the Sieur de la Menardière, and that in its turn an 'Apologie pour Mr. Duncan, Docteur en Médecine, dans laquelle les plus rares effects de la Mélancholie et de l'imagination sont expliquez contre les reflexions du Sieur de la M$^{re}$ par le Sieur de la F. M.' La Flèche (no date). Duncan also wrote a treatise entitled 'Aglossostomographie' on a boy who continued to speak after he had lost his tongue, pronouncing only the letter r with difficulty. The faulty Greek of the title, which should have been 'Aglossostomatographie,' was very severely criticised in prose and verse by a rival physician of Saumur, named Benoit. Duncan resided at Saumur until his death, which took place in 1640, to the regret, it is said, of protestants and catholics alike. He had issue three sons, who took the names respectively of Cérisantis, Saint Helène, and Montfort.
His eldest son, Mark Duncan de Cérisantis (d. 1648), was for a time tutor to the Marquis de Faure, and was employed by Richelieu in certain negotiations at Constantinople in 1641; but in consequence of a quarrel with M. de Caudale was compelled to leave France, and entered the Swedish service. He returned to France as the Swedish ambassador resident in 1645. Shortly afterwards he quitted the Swedish service, renounced his protestantism, and went to Rome, where in 1647 he met the Due de Guise, then meditating his attempt to wrest the kingdom of Sicily from Spain, whom he accompanied to Naples in the capacity of secretary. He is said also to have been secretly employed by the French king to furnish intelligence of the duke's designs and movements. He died of a wound received in an engagement with the Spaniards in February 1648. The authenticity of the 'Mémoires du Duc de Guise,' published in 1668, was ​impugned by the brother of Cérisantis, Saint Helène, mainly on the ground of the somewhat disparaging tone in which Cérisantis is referred to in them. The genuineness of the work is, however, now beyond dispute, and it must be observed that the duke, while imputing to Cérisantis excessive vaingloriousness, gives him credit for skill and intrepidity in the field. Cérisantis was esteemed one of the most elegant Latinists of his age, and published several poems, of which ‘Carmen Gratulatorium in nuptias Car. R. Ang. cum Henrietta Maria filia Henrici IV R. F.’ is the most celebrated.
J. M. R.