What Leonardo da Vinci weapon used many small barrels to fire in sequence?

Leonardo da Vinci’s 33-barrelled organ was a multiple-barrel firearm concept designed to fire a volley from many small guns.

The design arranged 33 barrels in three rows of 11. The name “organ” refers to the visual resemblance between the parallel barrels and the pipes of a musical organ. Its purpose was to increase the number of shots delivered in a short period, rather than to create one exceptionally powerful projectile.

The weapon belongs to the family of organ guns, also called ribauldequins or volley guns. It should not be confused with a modern machine gun: Leonardo’s concept depended on loading and firing separate barrels, and the surviving drawing does not establish that he built a successful battlefield example. The design illustrates his interest in improving artillery rate of fire through arrangement and repetition.