The Darne company was one of relatively few private arms manufacturers in France, best known for shotguns. During World War One they got into the machine gun trade, making licensed Lewis guns for the French air service. After making a few thousand of those, Regis Darne designed his own belt-fed machine gun in 1917. A large order was placed by the French military, but it was cancelled before production began because of the end of the war.
Darne continued to develop this design in the 1920s, while also producing sporting arms to keep the business running. The gun was intended mostly as an aircraft gun, but designed in a rather modular fashion, easily made into both magazine-fed and belt-fed infantry versions as well as downing, wing, and observer aerial models. It was actually bought by the French Air Force, as well as several other countries during the inter-war period.
The example we are looking at today is an infantry configuration, with a bipod and light-profile barrel. It is chambered for the French 7.5x54mm cartridge, and is officially the Model 1933 (one of the last iterations made). Many thanks to the Royal Museum of the Armed Forces and Military History in Brussels for access to this very rare piece! Check them out here: