The cartridge conversion Navy revolvers continued to be used by the U.S. Navy up until their replacement in the 1890s by the Colt Model 1889 double action revolver. This example, originally manufactured in 1856 and later converted to .38 centerfire, correctly falls into the serial number range of U.S. Colt Richards-Mason Model 1851 Revolvers as established by McDowell in "A Study of Colt Conversions and Other Percussion Revolvers" on page 232. The barrel is stamped with the New York address on the top flat and Commander Richard W. Meade inspection initials "R.W.M." followed by a Navy anchor marked on the bottom flat. "U S N" is stamped on the butt. "PAT. JULY. 25, 1871./PAT. JULY. 2, 1872." stamped on top of "COLTS/PATENT/US" on the left side of the frame. Matching serial number "59721" marked on the barrel, frame, trigger guard and back strap. The number "990/072" and the standard Texas Navy battle scene marked on the cylinder. "98" marked on the loading gate.