I grammatici tra libro e testo. Il caso di Orso beneventano

The codex 1086 of the Biblioteca Casanatense of Rome, with the Adbreviatio artis gramaticae of Ursus Beneventanus, is a case study particularly significant to deepen the relationship between author, text and book: in its first part the manuscript is an 'idiografo d'autore' because it reports the text 'fired' by the author; in the second one it collects the notes of the author himself, working materials stopped at a stage of sketch or partial drafting. A reconstruction of the figure of Ursus is attempted, a grammar teacher active in Benevento in the first half of the IXth century, and the didactic nature of his manual is deepened. Finally, some reservations are proposed at the recent critical edition of Barbara Maria Tarquini.