The Medieval Scales.

The medieval musical scales were called modes, which were described by their ranges, the location of the half-steps, the important pitches used at the beginning and end of the composition, and the "reciting tone"—the pitch used for recitation in psalms (see Plainchant, Psalms). During the Middle Ages there were eight modes, grouped into four pairs (this was enlarged to six pairs in the sixteenth century, and reduced to two—the major and minor scales presently in use—in the eighteenth century). Each mode was known by its number and by a Greek name. The names chosen were those of ancient Greek tribes that were believed to have exemplified the emotional character of that mode. Although the system of modes was originally invented to describe and control monophonic music, it was also applied...