a diastematic form, which could be written in such an analytical way. William of Volpiano and the Norman line William of Volpiano elaborated the concept of an additional letter notation and created a new form of tonary which became an important part of his monastic reforms, he did the first reform for Cluny, after he became abbot of St. Benignus of Dijon in Burgundy. Since 1001 he changed to the Abbey of Fécamp, after he was asked by the Norman Duke Richard II to guide secular and monastic reforms in the Duchy of Normandy. The fully notated tonary which he wrote for St. Benignus (F-MOf H159), is following the order of other tonaries, which were created under the influence of the Cluniac Monastic Association. These tonaries usually had sections dedicated to the antiphonary and the gradual, within the gradual and the antiphonary there were subsections like the antiphons which were sung as refrains during psalm recitation (introits and communions), responsories (the introduction of epistle readings), but also other genres of the proper mass chant as alleluia verses (the introduction of gospels), and offertories (a soloistic processional antiphon for the procession of the gifts). Several Aquitanian troper-sequentiaries had a libellum structure which sorted the genres in separate books like alleluia verses (as the first part of sequentiaries and tractus collections), offertorials, and tropers. But William of Volpiano subdivided these books into eight parts according to the octoechos system like the tonary, or the troparia in the Byzantine book Octoechos, and within these sections the chant was ordered according to the cycle of the liturgical year starting with advent. He used the neumes of Cluny, the central French forms, without changing them, but he added an own system of alphabetic notation in a second row, which defined the pitches of the melody precisely according to the Boethian diagramm. Like any other chant manuscript around 1000, the book was not written for a use during a ceremony, it was a "book of memory" for cantors who alone had the competence of reading and writing neumes, and the responsibility to organize the chant sung during the liturgical year. During his reforms, several Abbeys followed his example and his system was used by the teachers of the local grammar schools which included the daily practice of singing the liturgy. William's reform and its monastic foundations of Fécamp and the construction of the Abbey on the