What rotating artillery design did Leonardo da Vinci create with multiple gun barrels?

Leonardo da Vinci created a 33-barrel organ, a multi-barrel artillery design arranged to fire a broad volley.

The weapon used three rows of eleven small cannon barrels mounted on a wheeled frame. The name “organ” refers to the visual resemblance between the grouped barrels and the pipes of a musical organ. The frame could be angled, and the repeated barrels were intended to increase the speed and volume of fire compared with a single cannon.

Leonardo’s military notebooks contain many weapon studies, reflecting the practical market for engineering expertise in Renaissance Italy. The 33-barrel arrangement was designed as a field weapon rather than as a handheld firearm. It was never documented as a successful mass-produced weapon in Leonardo’s service.

The device should not be confused with a modern machine gun. It still relied on separately loaded gun barrels and black-powder artillery technology. Its importance lies in the attempt to solve firing-rate problems through mechanical arrangement.