​FLUE-WORK. Organ-stops, in regard to the manner in which their sound is generated, are grouped in two great classes—Reed-work and Flue-work. All organ-stops in which the sound is produced by the wind passing through a fissure, flue, or wind-way, and striking against an edge above, belong to the Flue-work, whatever may be the shape, make, or tone of their pipes. The peculiarities of shape or proportion, make, and tone, lead however to a subsequent division into Principal-work, Gedact-work, and Flute-work.