What artillery design did Leonardo da Vinci arrange with 33 small barrels?

Leonardo da Vinci arranged 33 small barrels in a 33-barrelled organ, an artillery design intended to fire multiple shots in succession. The barrels were grouped in rows so one set could be fired while another was prepared.

The name comes from the visual resemblance to the pipes of a musical organ. Leonardo’s proposal used a wheeled frame and several rows of barrels, allowing the weapon to deliver a broad volley rather than relying on one slow-loading cannon. It was part of his continuing interest in improving battlefield firepower.

The design was not a modern machine gun. Its barrels still required separate loading and firing, and the weapon’s practical rate of fire would have been limited by Renaissance gunpowder technology. Leonardo’s 33-barrel arrangement is also distinct from his other artillery concepts, including large crossbows and multi-barrel guns with different configurations.