The last act of Dungal of which we have any record is his gift of books to the library of Bobbio.[506] Dungal is greatly praised by Muratori, Mabillon, Bellarmine and others for his learning and he was valued both in Italy and France for his varied attainments. Muratori, who published a catalogue[507] of the library of Bobbio, says that “Dungal carried into Italy the Scotic love of learning.” Among the books which Dungal presented to Bobbio is one which was catalogued as Psalterium but named by Muratori as the _Antiphonary of Bangor_,[508] a book of hymns compiled expressly for the use of the monastic community of Bangor in Co. Down (Ireland). It is written in Latin, but it contains the strongest internal evidence of its Irish origin. On the strength of the evidence furnished by the fact that Dungal possessed this book many believe that Dungal himself was a pupil of Bangor. If so, we have in Dungal an excellent example of the type of education available in this famous monastic school in the ninth century. SEDULIUS: Under the Emperor Lothair 840–855 there was at Liège a colony of Irish teachers and writers of whom the best known is Sedulius, sometimes called Sedulius the Younger to distinguish him from the author of the _Carmen Paschale_. We have already referred to the fact that he was a distinguished poet[509] and a learned grammarian.[510] He is no less famous as a scribe[511] and as a writer on other subjects. He wrote an important treatise on the theory of government entitled _De Rectoribus Christianis_.[512] This work was written at Liège probably about the year 855 A.D. It is in reality the first systematic contribution of the Middle Ages to the theory of political government and should rank in importance with St. Thomas’s _De Regimine Principis_, with Colonna’s _De Regimine Principum_ and with Dante’s _De Monarchia_.[513] As its latest editor Dr. Hellman has remarked, if this work is not drawn from exclusively Irish sources, it is drawn at least from sources which were held in high esteem by Irish writers of the Carolingian Age. This Celtic conception of the duties of a Christian ruler is of very special interest to the student of mediæval political theories. Its sources are Christian and classical, its immediate object was the direction of a Frankish ruler (probably Lothair II.), the mind that conceived it was Celtic and here we have at the beginning of mediæval speculation a combination of forces and interests which went to make up the mediæval policy.[514] Sedulius also wrote a commentary of Porphry’s _Isagoge_ (or Introduction to the Logic of Aristotle) for which the basis may have been the Greek text though the work was known to other Christian logicians only in the Latin translation.[515] JOHANNES SCOTUS ERIUGENA (d. 877 A.D.):