Leonardo da Vinci’s organ-like rapid-fire weapon design contained 33 barrels.
The device is commonly described as a multi-barrel cannon or organ gun. Its barrels were arranged in a fan-shaped or organ-like configuration so that several shots could be fired in sequence. The arrangement was intended to increase the rate of fire while allowing one group of barrels to cool and another to be loaded.
Leonardo’s military notebooks contain many studies of artillery, fortifications, and battlefield machines. The 33-barrel design reflects a practical concern of Renaissance warfare: ordinary gunpowder weapons were slow to reload, and concentrated fire could disrupt an advancing formation.
The weapon should not be confused with a modern machine gun. It had no automatic loading mechanism and depended on manual preparation and black powder. It is also often confused with Leonardo’s other military sketches, including armored vehicles and giant crossbows.