Described only by Irwin, who says: �A manual or pedal mixture composed of Foundation ranks of open metal construction, designed to amplify the sub-unison series of pitches.� Hopkins & Rimbault give the composition below, but do not define the name.
Quint Mixture II (12,15), Great; The Grove Organ, Tewkesbury Abbey, Gloucestershire, England; Michell & Thynne 1885.