On page 945/r/ of the Codex Atlanticus, Leonardo da Vinci drew many devices for the plan of a mechanical paddle boat. One or more sailors can alternate working the pedals. The pedals transfer the alternate motion to a central gear, where it becomes linear motion, and a series of gears transfer it to the two big paddles on the sides of the craft. The central gear is drawn in more accurately on another page, 30/v/, and the mechanism works through springs hidden in the two main wheels that alternate