Concertina

Double concertina prototype, with the fingering system described in Wheatstone's 1844 patent. The instrument has a circular baffle mounted on the inside fo the reed pan, and a deep central fold in the bellows containing a wood and leather panel separating left from right halves. Flat, solid rosewood ends (left hand only) 6.56in/167mm across parallel sides, thick simple frets with pine backing. No finger rests. Conventional split between end and action frame. 40 buttons, 20 each end arranged in 4 columns. The action is of conventional sheet brass levers, wound brass wire springs, and sheet brass pivots, stapled directly onto the action board. Square-end brass reed beds, with nickel tongues, some beds with notches (indicating the potential site of screws). Circular baffle screwed to wooden annulus around central hole, supported on cork blocks. The lower notes were once screwed onto the pan rather than slid into related notches. The pan is unusually deep and has a 4.875in/124mm diameter circular wooden baffle screwed to a wooden annulus mounted around the pan hole, and supported on cork blocks, to either concentrate the air flow or protect the reed tongues from touching the bellows. Two sets of three-fold bellows, dark green leather, separated by a 1.875in/47.6mm wide central section containing a partially completed system of wooden baffles, with leather seals. The central baffle allows left and right hands to be played independently with varying pressure and volume. Gold dots and circles papers. Bellows frame has silk-reinforced lower folds and triangular block reed pan cradles. Broad green leather strap with nickel screw, with round brass inset to action frame. All parts are stamped L or R (for left or right). No label, though the left-hand number area is illegibly stamped. Serial number 5 (inked beneath action board).