AURELIANO di REOMÉ. - French monk who lived in the 9th century. His treatise De musicae disciplina, written around 830, of which two manuscripts are preserved, one in the abbey of S. Armando and the other in the Biblioteca Laurenziana in Firenze, summarizes, in its own way, the doctrine of s. Agostino, of Marzano Capella down to s. Beda, and is intended as a summary of what the musician must know in order to distinguish himself from the mere singer. Among the somewhat confused explanations of the neumes, it lays down the famous rule for the “tristropha”: “trinum ad instar manus verberantis facias celerem ictum” (chap. XIX). When it speaks of the transposition of the modes, and of certain formulas for the psalms,
it has not been possible clearly to determine whether it attributed them to fixed modality or not. It is interesting, however, as a study for the classification of the modes attributed to various antiphons, and it bears witness to how this part of ancient modality should be studied, before the systematization of the Middle Ages.