 He suffered from poor health during his years as an officer and this led to him requesting a non-active military position as a professor of mathematics.He gained the attention of Adrien-Marie Legendre with some of his work and through Legendre's recommendation, he was assigned to his first academic position, as a professor at the École d'Artillerie in Besançon in July 1801.He would go on to teach at a number of different artillery schools through France, including ones in Châlons-sur-Marne (March 1802 - December 1802), Metz (December 1802 - February 1808, 1815–1816), and La Fère (February 1808 – 1814, 1814-1815).