The Arcelin system was a capping breechloader provisionally adopted by the French military in 1854. It was a bolt action system with a folding bolt handle, firing a paper cartridge. It impressed Emperor Louis Napoleon III in initial trials, and he directed it be used to arms his elite Cent Gardes bodyguard. More extensive testing showed that it suffered from insufficient obturation, and would would with extended use, eventually becoming so difficult to close that bolt handles would break. Its adoption was rescinded, and it was replaced by the Treuille de Beaulieu 9mm pinfire carbine in Cent Garden use within just a few years.
The most distinctive element of the Arcelin in use was its bayonet – a true full-length sword complete with brass handguard that could be clipped to the muzzle. This was chosen for its impressive length, although it would have been cumbersome if used beyond ceremonial guard duties.
Thanks to the Cody Firearms Museum for allowing me access to film this very rare and very cool musketoon and its bayonet!