The first mention of a collection of chants occurs about the year 760 when Pope Paul I sent to King Pepin an Antiphonal and a Responsal.[58] In the time of Charlemagne there existed a missal and breviary called Gregorian, as we gather from a letter addressed to the emperor by Pope Hadrian. This is the earliest mention we find of the Gregorian tradition, and it is not very enlightening. The first writer to give us much information about the liturgy is Amalarius, who was deacon of Metz under Louis the Pious. Aurelian of Réomé (_ca._ 859) classes the melodies according to the order of the eight ecclesiastical modes, and Regino, Abbé of Prum, toward the end of the same century gives us in his _Tonarius_ an extended catalogue of anthems and responses, accompanied by a neumatic notation. We find again a hazy reference to Gregory by Walafrid Strabo under Louis the Debonair, and it is only when we come to the life of St. Gregory, written by John the Deacon about 882, that we find an explicit and unequivocal ascription of the existing collection of liturgical chants to that pope.[59] The scarcity of references to the Gregorian tradition among writers prior to John the Deacon is curious. Isidor of Seville and the Venerable Bede, both of whom occupied themselves much with the liturgy, are silent on the point; so is the _Liber Pontificalis_. Gregory’s own writings are singularly lacking in references to music. His only utterance on the subject that has been preserved to us is the decree of the Synod of 595 in which he condemns the tendency of the priests to be more preoccupied with the effect of their voices than with the import of what they sing, and orders that they confine themselves thenceforth by reciting the Gospel in the celebration of the mass and leave the singing to sub-deacons and clerics of inferior grade. This would not of itself imply any great devotion on Gregory’s part to liturgical music, though the necessity of training clerics of inferior grade to sing the services might have suggested the founding of the _Schola Cantorum_ which is traditionally ascribed to him. It is pointed out by Gevaert that the _Antiphonarius Gregorianus_ does not fit the ecclesiastical calendar of the time of St. Gregory, but belongs to the liturgical usage of Rome about the year 750.[60] Duchesne credits the editing of the Gregorian missal to Pope Hadrian during the first years of Charlemagne’s reign. The name Gregorian may have reference to Gregory II (715-31) or, more probably, to Gregory III. It is a fact that until the end of the seventh or the beginning of the eighth century the churches did not open on Friday, and it was not allowed to celebrate mass on that day, because it coincided with the Pagan feast of Jupiter (_Jovis Dies_). Even as late as the end of the sixth century the celebration of this festival was so common that it was solemnly condemned by the Council of Narbonne (589). By the eighth century,