Leonardo da Vinci sketched a miter lock for canals and water engineering.
A miter lock uses two gates that meet at an angle pointing upstream. Water pressure pushes the gates together, helping them seal the opening when the water level differs on the two sides. Leonardo studied canal systems in northern Italy and drew mechanisms for controlling water, including lock gates and related hydraulic equipment.
The miter-gate principle is especially useful in navigation locks because it allows boats to pass between water levels. Operators close the gates, equalize the water level through controlled openings, and then open the opposite gates. Leonardo’s hydraulic studies connected practical transport problems with his broader investigations of water flow.
Leonardo did not invent every component of canal-lock technology. Earlier water-control systems existed, and historians distinguish between Leonardo’s designs and the later construction of specific locks. His sketches are significant because they show detailed analysis of gates, channels, and the forces acting on moving water.