Michel Corday (1870-1937) was the pseudonym of the French soldier and author Louis-Léonard Pollet. He wrote two significant science fiction novels, late in his life: La Flamme éternelle (1931) and its sequel Ciel Rose (1933). These have been translated together in one volume by Brian Stableford, as The Eternal Flame (2013). The Encyclopedia of Science Fiction says of these books “the invention of a new power source is scrutinized with unusual sophistication in terms of its Economic consequences.”
The Lofficiers mention other relevant books: Le Mystérieux Dajann-Phinn (1908); Le Fiancé aux Deux Visages (1908); Le Lynx (with André Couvreur, 1911); and En Tricogne: Un an chez les Tricognes (1926).
He was born in Paris, and was enrolled for the Polytechnique in 1888. However, he went to the École d’application at Fontainebleau, and trained as an army engineer. For a while he was garrisoned at Versailles. He left the army in 1895; his first novel had been published in 1894. He was very interested in novels that explored social and economic issues, but was also known for his novels dealing with the army: Intérieurs d’officiers (1894) and Coeurs de soldats (1897). With a break during the Great War, he published roughly a novel a year until the 1930s.
He kept and published a diary about life during the Great War (on which see his entry). After the war he involved himself in pacifism, and attacked those who made profits from the war. He also got interested in a possible member of his family: Charlotte Corday, the assassin of the Revolutionary leader Marat.
My information comes from a brief note by R. Limouzin-Lamothe in the Dictionnaire de Biographie Française, fascicule 51 (Paris 1960), and from Jean-Marc Lofficier and Randy Lofficier, French Science Fiction, Fantasy, Horror and Pulp Fiction (Jefferson NC and London: McFarland, 2000).