Porchfest 2011
September 25

A division on a ground
performed by Maurice Steger


sadly, only a short clip

More on hands

Helperic used a diagram of the hand as a mnemonic device for determining the correct date of Easter. Guido of Arezzo used a diagram of a hand, in which a musical note is assigned to each fingertip, joint and knuckle. 


In the diagram in the image below, note the labels "diatessaron" and "diapente," referring to a perfect fourth and a perfect fifth. 


(See blog entry of March 8, 2011)

From a manuscript in the British Library

Helperic and Guido of Arezzo, Miscellany of treatises relating to computus and music, imperfect at the end, including Helperic's 'Liber de computo' (ff. 2-55v); Guido's 'Regulae rhythmicae' (ff. 55v-56), 'Prologus in Antiphonarium' (ff. 56v-58), 'Epistola ad Michaelem (ff. 58v-65) and 'Micrologus' (ff. 79-88v, 91v-94v); 'Musica enchiriadis', excerpt (ff. 65-69v); computus text (ff. 71-74); 'De tonis', dialogue (ff. 74-79); office of the nativity of the Nativity of Virgin Mary’ (ff. 89-91). England or France; 1st half of the 12th century.