What type of cannon did Leonardo da Vinci propose using three rotating barrels?

Leonardo da Vinci proposed a triple-barrel cannon using three barrels arranged together.

The design is commonly known as a three-barrel or triple-barrel cannon. Leonardo explored artillery concepts that could increase firing speed by allowing one group of barrels to be loaded while another was firing or cooling. Multiple barrels could also provide a broader spread of shot than a single gun.

The idea belonged to Leonardo’s wider interest in military engineering during the late 15th century. His notebooks contain designs for fortifications, bridges, armored vehicles, artillery, and other battlefield machines. Many were proposals rather than completed weapons, and their practical performance was never proven in combat.

The triple-barrel cannon should not be confused with the later revolving gun or modern multi-barrel automatic weapons. Leonardo’s design used the technology of Renaissance gunpowder artillery, with heavy barrels and manual loading. Its importance lies mainly in the attempt to solve the slow reload problem through multiple firing tubes.