Leonardo da Vinci used miter gates in plans for improved canal locks.
A miter gate consists of two leaves that meet at an angle, usually pointing upstream. Water pressure pushes the leaves together against their central meeting point and the side walls, helping the gate resist the force of the water. This arrangement became a major development in canal engineering.
Leonardo worked on hydraulic engineering and canal projects in northern Italy, where reliable water transport was economically important. His notebooks include studies of lock mechanisms and water control. The design is often associated with Leonardo because of his detailed investigations, although the broader history of canal locks involved earlier engineers and construction traditions.
A canal lock raises or lowers boats between water levels by filling or emptying a chamber. Miter gates are not the same as simple sluice gates, which control water through openings. Leonardo’s hydraulic studies also covered canals, pumps, and methods for managing water flow.