What machine did Leonardo da Vinci design to fire multiple guns in a volley?

Leonardo da Vinci designed a 33-barrel organ to fire multiple guns in a volley.

The weapon consisted of three rows of eleven small cannon barrels mounted on a wheeled frame. The arrangement resembled the pipes of a musical organ, which explains the name commonly used for the design. The rows could be fired in sequence, allowing one group to cool while another was used.

Leonardo’s purpose was to improve the rate and continuity of artillery fire. The design appears in his military notebooks, but there is no firm evidence that Leonardo constructed or tested a working 33-barrel organ. It belongs to a large group of Renaissance military concepts that combined existing weapons with mechanical systems.

The name can cause confusion: this was not a musical organ and did not use sound-producing pipes. It was a multi-barrel gun platform. It is also distinct from a modern machine gun, because each barrel was a separate cannon and the concept depended on volley fire rather than automatic loading.