Leonardo da Vinci designed a miter lock using two connected gates to control water levels in a canal.
A miter lock has gates that meet at an angle, with the point facing the higher water. Water pressure pushes the gates together and helps seal the opening. Leonardo used this principle in canal-engineering designs associated with Milan, where waterways were important for transport, irrigation, and construction.
Leonardo is often credited with improving the miter lock rather than inventing the basic concept from nothing. His designs included practical details for operating gates and managing changing water levels. The system allowed boats to pass between sections of canal at different elevations.
The term “miter lock” is more precise than simply “canal lock,” because a canal lock is the broader system while the miter refers to the characteristic meeting arrangement of the gates. Leonardo’s work helped document and refine water-control technology during the Renaissance.