Once he graduated, he became a mathematics teacher the Lycée de Dijon in Saint-Cyr.
After the declaration of World War I, Antoine served as a reserve lieutenant in the 72nd Infantry Regiment of Amiens, and later a commander on the machine gun of the 151st Infantry Regiment.
In 1917, he lost his sight as a result of bullets hitting his eyes.
Antoine was assisted by his friends during his studies, who produced braille copies of mathematical papers.
Antoine developed a system of braille mathematical notation, with the assistance of a student at École Normale Supérieure.