In 1797, Robert Fulton (1765-1815), a Pennsylvania- born artist and inventor, offered to build a submarine for the French, who were then engaged in a bitter war with Britain. He proposed to use the vessel to sink Royal Navy warships blockading French ports. The French government hesitated to become involved in what they regarded as a dishonorable style of warfare. Undeterred, Fulton went ahead with developing his machine, gaining French financial backing after Napoleon made himself First Consul in 1799.
Fulton's "mechanical Nautilus" was launched on the River Seineat Rouen in 1800. Its inventor described it as "six and a half meters long and two meters wide... built entirely of wood." It had a mast and sail for propulsion on the surface, which were lowered when it submerged by filling its water tanks. The crew of two to four could stay underwater for around four hours thanks to a supply of compressed air. Submerged, the vessel was driven by a hand-cranked propeller and could maneuver using vertical and horizontal rudders. The interior was lit by candles and a glass cupola allowed the crew to see around them when semisubmerged. Like Bushnell's Turtle of 1775, the Nautilus depended on underwater explosives— primitive sea mines—to attack enemy ships.
After successful tests in the Seine, the Nautilus showed its ability to sink a target ship at Brest in July 1801. However, the French refused permission for Fulton to attack British warships and withdrew their support. Fulton tried to interest Britain in his invention, but as the dominant naval power they had no motive to pursue a revolutionary form of warfare.
