Also known as the Model 1855, which quickly became known as the "Root" after Colt Superintendent at the time Elisha K. Root, the Model 1855 marked Colt's return to the manufacture of shoulder arms and can be attributed to the introduction of a New Model pocket pistol. This is one of approximately 2,000 carbines sold through Colt's London Agency. This rare carbine is marked with British "crown/GP" and "crown/V" proofs on the left rear barrel flat below the rear sight and alternating in each cylinder flute. The top strap is marked "COL. COLT HARTFORD CT. U.S.A.", one of the cylinder flutes is stamped "PATENTED SEPT. 10, 1850" and the left side of the receiver is marked "COLT'S PATENT/NOV. 24th 1857" directly above and ahead of the saddle ring and stud. The matching serial number is marked on the bottom of the barrel, frame, lower tang and the buttplate toe. The upper left rear of the trigger guard is marked with the letter "P". Pinched brass front sight with folding three leaf rear sight (one fixed, two folding) marked for 100, 300, and 600 yards. The barrel, cylinder and frame are blue, loading lever and hammer casehardened, brass trigger guard and buttplate, and the carbine is mounted with a smooth oiled black walnut straight grip stock with crescent buttplate.

Fair. The carbine has a smooth cleaned gray patina with extensive deep pitting overall. The brass has a bright appearance with a dark patina in the protected areas. The very fine stock has nice raised feather grain with some scattered minor handling marks. Mechanically fine.