What propulsion method did Leonardo da Vinci’s paddle boat use?

Leonardo da Vinci’s paddle boat used paddle wheels for propulsion.

Leonardo designed boats in which rotating wheels fitted with paddles would push against the water. Crank mechanisms and gears transferred power from people turning handles to the wheels. The arrangement was intended to produce movement without relying on oars or a favorable wind.

Paddle wheels had appeared in earlier Chinese and European ideas, so Leonardo should not be credited as their sole inventor. His contribution was to analyze and draw practical mechanical arrangements for using them on boats. His notebooks show repeated interest in converting rotary motion into useful movement.

The design also differs from a later steam-powered paddle steamer. Leonardo’s boat depended on human mechanical power, not a steam engine. The same broad propulsion principle later became important in riverboats and early steamships, where engines replaced the rowers or operators.