CHRONOLOGICAL  TABLE

Pythagoras, c . 582—500 B.C . Determines the ratios of the diatonic scale . Aristoxenus, fl . 320 B.C . Our chief authority on classical Greek music . Ptolemy, ft . A.D . 130 . Astronomer, geographer, mathematician and writer on music . Reforms the Greek modes so as to prepare the way for the ecclesiastical modes . St Ambrose .

Arranges the Ambrosian tones of

church music, A.D . 384 . Hucbald, c . 84o-930 . Systematizer of Diaphonia or Organism (called by him Symphonia), and inventor of a simple and ingenious notation which did not survive him . Guido of Arezzo, c . 990-1050 . Theorist and systematizer of musical notation and solmization . Franco of Cologne, iith century author of treatises on musical rhythm . Works under the name of Franco appear at dates and places which have led to the assumption of the existence of three different authors, who, however, have been partly explained away again; and the 11th century is sometimes called the Franconian peciod of discant . Discantus positio vulgaris . An anonymous treatise written before I15o; is said to contain the earliest rules for " measured music," i.e. for music in which different voices can sing different rhythms .

The

Reading MS., c . 1240 (British Museum, MS . Hari., 978, fol . 11 b.), contains the rota " Sumer is icumen in." Walter Odington, fl . 1280 . English writer on music, and composer . Adam de la Hale, 1230–1288 Connecting-links between the trouba-Machault, fl . 1350 dours and the archaic contrapuntists . John Dunstable, died 1453 . English contrapuntal composer . G . Dufay, died 1474 .

Netherland contrapuntal composer . (These two are the

principal founders of artistic counterpoint.) Josquin Des Pres, 1445–1521 . The first great composer .