What type of lock did Leonardo da Vinci design to control water in canals?

Leonardo da Vinci designed a mitre lock to control water levels in canals.

A canal lock allows boats to move between sections of water at different elevations. Mitre gates meet at an angle pointing upstream; water pressure helps press their angled edges together, creating a seal when the gates are closed.

Leonardo worked on canal and hydraulic engineering in northern Italy and designed improvements to lock mechanisms. His studies addressed practical problems such as navigation, water control, and the movement of boats through changing levels.

Leonardo did not invent the basic canal lock, and earlier locks existed in Europe. His importance comes from refining hydraulic designs and documenting mechanisms with detailed drawings and observations. A mitre lock is different from a simple sluice, which regulates flow but does not create a navigable chamber between two water levels.