An Irish translation of medieval Latin texts. The astronomical tract is based on a medieval Latin version of a work by Messahalah, a Jew of Alexandria who wrote in Arabic c. 815. The medical treatise is the work of Petrus Musantinus. There is also an incomplete medical philosophical treatise (five leaves, pages 23-26, 29-32). The text is written in a small neat hand in double columns with finely executed geometrical drawings. The frontispiece is an astronomical rotula with a moveable index attached, illuminated with red and yellow pigment. It has the name of the signs of the Zodiac, the planets, the months and numeral figures.

There are two other similar astronomical manuscripts, MS Z 2 1 in Marsh’s Library and RIA MS 23 F 13 (Cat. No. 1217) in the Academy. The three manuscripts are defective at the end, without the name of the scribe or location. Recent scholarship has identified the scribe of RIA MS B ii 1 as Aedh Buidhe O’Leighin of Fermoy, who was also the scribe of a herbal vellum in the Library of Trinity College.

The name Donncha O’Convill is written in ornate capitals on page 22; he is considered to have been a former owner rather than the scribe. In 1763, the manuscript was acquired by Thomas Astle and came to the Duke of Buckingham’s library at Stowe in 1806, and ultimately, as part of the Ashburnham Collection, it was given to the Academy with the Stowe Manuscripts in 1883.

In 1993-1994, the manuscript was disbound from the 1765 calf binding which was blind tooled in an interlaced design. The leaves were flattened, cleaned and repaired where necessary and rebound in a sympathetic style by Mathew Cains, Delmas Conservation Bindery. The cost of £2,550 was funded by a grant from the Boehringer Ingelheim Foundation, Stuttgart.

Digital images of the manuscript can be viewed on Irish Script on Screen.

Astronomical and Medical Tract, B ii 1, p.12

Further Reading

Catalogue of Irish manuscripts in the Royal Irish Academy Fasc. 26: pp. 3261-3266 (Dublin, 1943).

M.H. Close, ‘Remarks on a cosmographical tractate in the Irish language in the Library of the Royal Irish Academy’, Proceedings RIA, 22 (1900-1902), pp. 457-64.

J.E. Gore, ‘An Irish astronomical tract’, Knowledge (1909).

Aoibheann Nic Dhonnchadha, ‘The “Book of The O’Lees” and other medical manuscripts and astronomical tracts’ in Treasures of the Royal Irish Academy Library edited by Bernadette Cunningham and Siobhán Fitzpatrick (Dublin, 2009), pp. 81-91.

T. Ó Concheanainn, ‘The scribe of the Irish Astronomical Tract in the Royal Irish Academy B ii 1’, Celtica, 11 (1976), pp. 158-67.

‘An English translation’ by J.J. O’Farrelly (RIA MS 3 A 9).

M. Power, ‘An Irish astronomical tract, edited with preface, translation and glossary’, Irish Texts Society, Vol. 14 (London, 1914).