Leonardo da Vinci designed a paddle boat using rotating paddle wheels for propulsion.
Leonardo’s watercraft sketches show wheels fitted with paddles that would push against the water as they turned. Cranks and mechanical linkages were intended to let people supply the power. The arrangement resembles later paddle boats, although Renaissance versions were smaller concepts and lacked the steam engines that eventually made paddle-wheel vessels practical on a large scale.
The proposal belongs to Leonardo’s wider work on canals, locks, pumps, and military engineering. Paddle propulsion could move a craft without relying on wind, a useful idea for maneuvering on rivers and in calm conditions. It also offered a way to concentrate human effort through mechanical transmission.
Leonardo’s design was not a modern steamboat. The paddles were human-powered, and there is no evidence that his exact craft entered regular service. Nor should the sketch be confused with a ship propelled by a single stern wheel; Leonardo explored several arrangements for transferring motion from people to water.