CASIRI, MIGUEL (1710–1791), a learned Maronite, was born at Tripoli (Syria) in 1710. He studied at Rome, where he lectured on Arabic, Syriac, Chaldee, philosophy and theology. In 1748 he went to Spain, and was employed in the royal library at Madrid. He was successively appointed a member of the Royal Academy of History, interpreter of oriental languages to the king, and joint-librarian at the Escorial. In 1763 he became principal librarian, a post which he appears to have held till his death in 1791. Casiri published a work entitled Bibliotheca Arabico-Hispana Escurialensis (2 vols., Madrid, 1760–1770). It is a catalogue of above 1800 Arabic MSS., which he found in the library of the Escorial; it also contains a number of quotations from Arabic works on history. The MSS. are classified according to subjects; the second volume gives an account of a large collection of geographical and historical MSS., which contain valuable information regarding the wars between the Moors and the Christians in Spain. Casiri’s work is not yet obsolete, but a more scientific system is adopted in Hartwig Derenbourg’s incomplete treatise, Les Manuscrits arabes de l’Escorial (Paris, 1884).