Patented in England ca. 1817 by Urbanus Sartoris of Milan. Sartoris Patent was an improvement on the Guiseppe Crespi system, with Forsyth type detonator lock (complete with parts to convert lock to use percussion caps). Marked "Patent" on bolt lever and the letters "ABF 54" and a British proof under chamber. Condition is overall very fine to excellent. Bore is mint; action, trigger guard and buttplate are finely engraved. Trap in butt contains percussion converison parts. Three-stage barrel retains a nice Damascus pattern. Two gold bands on breech block. Wood is very fine, with normal handling marks and one small stress crack on forearm. An extremely interesting firearm.