Trinitas, unitas, deitas – a trope for the Sanctus of mass

Abstract

The melody for the verses beginning “Trinitas, Unitas, Deitas” has so far been published only from three French sources of the 13th century. Amedee Gastoue gave the melody in the course of his essay ‘Les anciens chants liturgiques des Églises d'Apt et du Comtat’; his transcription was based on the manuscript Apt 6 (No. du fonds 1), a mass-antiphoner of the 12th century used at the church of St.Pierre in Apt, with additions in various hands on the unfoliated leaves after folio CXII at the end of the manuscript, which is where we find Trinitas, Unitas, Deitas, between a troped Kyrie and a Christmas song. Henri Villetard (1907) and Wulf Arlt (1970) published the melody as part of their respective editions and commentaries for the New Year's offices of Sens and Beauvais, from the manuscripts Sens 46 and London, B.L., Egerton 2615, that is, from two sources of the early 13th century whose contents are related, and which may be seen as recensions of a 12th-century exemplar no longer extant.