Ecclesiastical Modes

Octave sections of the fundamental scale of med iæval music (first space in the ba staff to third space in the treble without chromatics), constructed by the ch. musicians of the Middle Ages in imitation of the ancient Greek modes. According to tradition St. Ambrose established the first four, which were called Authentic: Dorian, D in the ba to d above; Phrygian, E in the ba to e above; Lydian, F in the ba to f above; Mixolydian, G in the ba to g above. To these four others, each beginning a fourth below and having the same name with the prefix prefix hypo-, were added by St. Greg. ory. Two Authentic, Ionic and Æolian, and two plagal modes, Hypoionic and Hypoæolian, were added by later the or i tic i ans. The scales thus formed were the basis of church music until supplanted by the modern system of major and minor keys.