Cognet de Seynes / C de S (France) - AllCarIndex

Automobiles Cognet de Seynes was a French automobile manufacturer based in Lyons, active from 1912 until 1926. The company was established through a partnership between Edouard de Seynes, a wealthy enthusiast, and Victor Cognet, a skilled engineer known for inventing a constant-mesh gearbox. Their initial efforts included the production of one or two prototypes of a small car before officially commencing production in 1912.

The first model featured a 1,122 cc four-cylinder side-valve engine paired with a three-speed gearbox. Notably, the design incorporated a propeller shaft and rear axle enclosed in an oil-filled cylindrical sump, which reduced friction and allowed the vehicle to reach speeds of up to 35 mph (56 km/h). Initially, the company offered only a four-seater tourer, although de Seynes had a custom-built aluminum two-seater for personal use in 1914. Production continued sporadically during World War I, with the company also manufacturing components for Anzani aero engines.

In 1920, the company underwent a change in ownership, and the vehicles were rebranded as C de S. The new management aimed to produce 300 cars annually, including a six-cylinder model, but these ambitions were not realized, and the new owners soon left. Edouard de Seynes regained control and resumed production at a reduced scale, manufacturing approximately 20 to 30 cars per year. The post-war models featured minor mechanical updates, such as a longer wheelbase and full electric equipment, while their design reflected the early 1920s aesthetic, characterized by disc wheels and a slightly V-shaped radiator.

By the time of its closure in 1926, Automobiles Cognet de Seynes faced significant competition from mass producers, which ultimately led to its demise. Although sales were primarily local, one of their cars reportedly reached Hankow, China. After the company's closure, Edouard de Seynes took on a role as commercial director at Rochet-Schneider and served as a driving examiner. Today, two examples of Cognet de Seynes cars are known to survive.