The 'picture' of the French Romantic positive organ above reminds me of an article in 'Organ Building' Volume Fourteen (2014) published by the IBO. Titled 'Monsieur Debierre's Polyphone Organ' , John Rowntree introduces the 1922 Le Mintier and Gloton organ (1919 successors to L Debierre) now in the Catholic Church of SS Peter and Paul Yeadon, Leeds, while Geoffrey Griffiths (organ builder from Portsmouth) explores the rejuvenation of this wonder of a bygone age. There are several colour pictures including two of the polyphones (and two weighted fly pallets built into the bottom of a wooden pipe fed from two pipe feet).