Siméon Bourgois was a 19th-century French Navy vice-admiral who was especially involved in the development of early submarines. He was born in Thionville, Lorraine, on March 26, 1815, and died in Paris on December 24, 1887. He held the rank of captain when he presented together with Bourdelle his project for the submarine Plongeur in 1858, and when he created the plans in 1860, under the code name Q00. Plongeur was the world's first submarine to be propelled by mechanical (by opposition to human) power.