Musica of Hermannus Contractus

the long version

"A polymath and monk, Hermannus Contractus (1013-54) contributed to the important advancements made in European arts and sciences in the first half off the eleventh century, writing on history, astronomy, and timekeepig devices, among other topics, and composing several chants. His music theory, founded on a systematic treatment of traditional concepts and terminology dating back to the ancient Greeks, is concerned largely with the oganization of pitch in Gregorian chant."--Provided by publisher.