A RARE GERMAN OVER-AND-UNDER FLINTLOCK SPORTING RIFLE with blued two-stage barrels each rifled with fourteen alternating broad and narrow grooves, the upper barrel with silver spider fore-sight and pierced and engraved saddle back-sight, gold vents and gold-lined counterfeit mounts of Alonzo Martinez of Madrid with six further decorative marks, the lower barrel with five decorative marks, and applied silver receiver for a sling mount, the tang with an applied shaped silver plaque on each side, flat lock with stepped tail and sliding pan for the upper barrel, retracted by the cock after discharge to reveal the pan for the lower barrel, figured walnut full stock with shaped silver mounts including skeleton butt-plate, cheek-piece, chequered grip, and engraved silver escutcheon gilt against a blued ground with the crowned arms of Salm within mantling (ramrod and rear sling mount missing), unsigned but almost certainly by Pierre Greverath à Dyck, circa 1820