Organistrum

[1] Generally considered the ancestor of later hurdy-gurdies, the organistrum differs substantially in that it was played by two individuals: one turned the crank while the other pulled the keys upward to change the musical pitch of the strings.

[2] The word organistrum is derived from organum and instrumentum; the former term was applied to the primitive harmonies, consisting of octaves accompanied by fourths or fifths, first practised by Hucbald in the 10th century.

In the earliest examples the wooden tangents[4] took the place of fingers on the frets and acted upon all three strings at once, thus producing the harmony known as organum.

It has the place of honour in the centre of the band of musicians representing the twenty-four elders of the Apocalypse in the tympanum of the Gate of Glory of the cathedral of Santiago de Compostela (12th century).

A fine example appears in a miniature of a psalter of English workmanship (12th century), forming part of the Hunterian collection in Glasgow University.