The youngest of five children, André-Gustave Citroën was born in Paris on this day in 1878. He developed a passion for engineering as he watched the construction of the Eiffel Tower, leading him to study at École Polytechnique in Palaiseau, France. During a visit to Warsaw in 1900, he witnessed a carpenter building a new type of gear system. He later purchased the gear patent to further developed it. This lead to the invention of double helical gears, commonly used in rear axles, transaxles, camshaft timing gears and other applications.
In 1906, Citroën became director of Mors automobiles, where he launched his automotive career. His success in the auto industry inspired him to found Citroën automobile company in 1919. Citroën would become the fourth largest automobile manufacturer in the world by 1932. Following overspending during development of the Traction Avant model, the company declared bankruptcy. In 1934, in the afternmath of the situation Michelin tire company took over Citroën. The very next year, André-Gustave Citroën succumbed to stomach cancer.