An English flintlock blunderbuss pistol with folding bayonet

An English flintlock blunderbuss pistol with folding bayonet, flaring brass barrel 7 in., private Tower proof marks, box lock engraved 'Waters & Co / Patent No 128'; cock (lacking top jaw) with safety bar, the triangular-section bayonet deployed by the action of a spring housed in a rotating brass drum below the muzzle, the point being held by a sliding catch concealed within the iron trigger guard and released by a secondary trigger; figured wooden grip with grotesque mask cap, side mounted ram rod (lacking tip), late 18th century.