Note 141 — Chapter X

Gerbert taught his disciples the use of the monochord; a single string, which being struck at different intervals, gave out the different sounds of the gamut. These intervals were marked on the chord, and the words to be sung had written over them a cipher, showing to what interval on the monochord it corresponded. A person therefore could always set himself right by sounding the note he wanted, as we should use a pitch-key. A description of this instrument is given by the monk Odoramn, whose works have been discovered and published by Cardinal Mai, and whose musical treatises are said to be based on the scientific principles of Boëthius and Euclid.