Morse cartridge alteration rifled muskets are described on pages 95-97 of George D. Moller's book "American Military Shoulder Arms Volume III", with this exact rifle photographed on page 96. The book states that only 2 initial muskets were shipped from Springfield to the Ordnance Office on April 22, 1859, and 54 additional rifles were completed by January of 1860. One of these was sent to Muzzy & Company (ammunition supplier to Ordnance), and 53 went to the Washington Arsenal. This system, first patented by George W. Morse in 1856 and improved in 1858, was used to create the first breech loading cartridge firearms produced by the national armories. Only a limited number of Morse conversions were conducted by the national armories at Harpers Ferry and Springfield just before the Civil War using existing Model 1841 rifles (at Harpers Ferry) and Model 1816 Muskets that had already been converted once from flintlock to percussion (both locations). Morse also patented the first center-fire cartridge, and thus, a proprietary center-fire cartridge with metal case was manufactured for these conversions. The alteration involved machining out the breech section of the barrel and installing a rather complex action and hinged "trapdoor". Moller states that of the 1,000 muskets selected to be converted, 544 were listed as "in the process of being converted" and were sold at auction. The other 400 were simply returned to the storekeepers since they remained in usable condition as percussion rifles. The rifle has a bayonet stud, blade front sight, folding ladder rear sight graduated 1-4 on the base and 5-8 on the ladder, an 1839 dated Springfield Model 1816 lock plate, standard Model 1816 stock marked with two circled script cartouches on the left flat, a circled script cartouche behind the lower tang, and a trumpet head ramrod. The breech block parts are numbered "3", "4" is marked on the left flat of the barrel at the breech, and "JO" is marked on the inside of the cocking lever, on top of the brass bolster, and on a part inside of the lock. "GDM" (George D. Moller) collection initials marked at the toe of the stock. Includes a US socket bayonet and leather sling. Provenance: The George Moller Collection