The MS. classed E. 3. 30, [=1435] a late vellum (? 16th century) in the library of Trinity College, comprises a number of medical tracts, written by various hands (Abbott-Gwynn. Cat. p. 309). The names of the scribes do not appear. The following text, which deals with the plague, occurs on p. 200, and is in a clear well-formed script, with the contractions usual in Irish medical MSS. There is another version in H. 3. 7. [=1326] (p. 111113), a vellum of the same period, the variant readings of which are added here. For the opening passage cf. Isidor, Origg. IV, 6 sections 17, 18. I have not found the subject treated separately elsewhere in Irish medical MSS., but there are several theological dissertations on it. Although H. has the title Sillanus de Nigris in Almansorem on the back of the modern cover, this treatise is not included in the editions of Sillanus super nono Alman. op. expositionem that I have examined.
The tract appears to be translated from or based on a Latin treatise. It bears a close resemblance to the chapter De febribus pestilencialibus in the section on fevers in John Mirfield's Breviarium Bartholomei. The Breviarium exists in two MSS., one in the British Museum and one in Pembroke College, Oxford. There is also a fragment of a third copy in the British Museum. None of them has been printed (Moore: Medicine in the British Isles). John Mirfield was resident in the Convent of St. Bartholomew, with which the hospital of the same name was connected, in 1392 and 1393. He was a theological scholar as well as a physician and medical writer of repute. His famous treatise is particularly of interest on account of his association with the oldest London hospital. His account of the plague is based on the chapter on the same subject in Bernard of Gordon's Lilium Medicinae, written at Montpellier in 1305. Mirfield was a close student of the Lilium and was also acquainted with the writings of John of Gaddesden and Gilbertus Anglicus. Compare section 2 in the tract with the following description
p.143in the Breviarium: Among the signs of approaching plague are comets and irregular seasons, etc. Also a warm and damp Summer, a time when birds desert their nests and when many reptiles appear on the surface of the earth.
Moore op. cit.; Lil. Med.. Part. I, Cap. X, de febribus pestilentialibus.
The language of the tract, which is early Modern Irish, is interesting, as it contains many unusual words: names of diseases, plants, and animals. The treatment of the subject illustrates the atmosphere which surrounded the study of mediaeval medicine. There is a certain amount of real medical knowledge, mingled largely with superstition and belief in astrology.
In H. 2. 15. TCD. [=1315] there is a marginal note mentioning the Great Plague of 1350, which was apparently raging in Ireland at the time: . . . & isi sin indara bliadain iar tichtain na plaga i nEirinn ro scribad sin. A later visitation of the plague is. mentioned in a note in H. 3. 17 [=1336]: . . . in fplaigh do beth ar lasad a Crichmhuill.
Plummer: Colophons and Marginalia of Irish Scribes.The great Plague is recorded in the Four Masters under the year 1349: Plaigh mór in Erind . & go hairidhe i Muigh Luirg go ttugadh ár diarmhidhe ar daoínibh da bithin. Matha mac Cathail uí Ruairc décc don plaigh hisin. The same outbreak is recorded in the Annals of Clonmacnoise under the year 1348.