Leonardo da Vinci’s 33-barrel weapon design is commonly known as an organ gun.
The design placed many small cannon barrels in a fan-shaped or organ-like arrangement. The visual resemblance to the pipes of a musical organ gave this family of volley weapons its name. Firing several barrels in succession or together could increase the volume of fire compared with a single muzzle-loading gun.
Leonardo’s version is preserved in his military-engineering drawings and is often described as a 33-barrel gun. The arrangement was intended to make reloading and firing more practical than using one enormous cannon, while also allowing the weapon to sweep a broader area.
It should not be confused with the later Ribauldequin, another multi-barrel artillery weapon, or with Leonardo’s giant crossbow. Leonardo’s organ-gun concept was a firearm battery, not a bow-powered machine.