This mid-18th century sporting gun has a straight rifled upper barrel and smoothbore lower barrel and is fired via a single lock with a two-layer priming pan that automatically retracts when the lock is re-cocked after the first shot. The flash for the second shot is transmitted down through the lock to the vent for the lower barrel. There is a removable cover for that flash channel underneath the mainspring inside the lock. The cock and tumbler are not bridled. It is certainly a very innovative and fascinating design, and it would be interesting to see how well it worked and if there was much of a "fuse effect" of the long flash channel for the lower barrel. Another impressive aspect of the craftsmanship of this gun is that the side panels that extend along the sides of the barrels are integral to the stock rather than separate pieces. The stock features very fine incised and raised relief scroll carving and has horn tips on the forend panels. The ramrod is carried on the left, and a sling swivel is on the right. The upper barrel has a silver blade front sight with flush silver base, and raised silver designs involving a gentleman in contemporary sporting attire at the breech. Both of the fire blued barrels have decorative bands at the transition points and breech ends, the latter with silver beaded accents. The rounded lock has a mask design on the fence of the priming pan and scroll patterns. There is a heart shaped marker's mark that appears to be "iVB" or "iVR" under the frizzen spring with the last letter mostly covered. The furniture is gilt brass and is cast and chased with scroll and floral patterns, a lion and lion mask design on the pierced side plate, and a coronet on the wrist escutcheon.

Fine with 50% plus of the niter blue style finish remaining on the barrel, mostly silver-gray patina on the lock, aged patina on the furniture, some pieces of furniture a little loose, and minor overall wear. The wood is fine and has crisp carving, some hairline cracks mainly in the forend, light scratches and dings, and general minor age and storage related wear. Mechanically excellent.