What was Leonardo da Vinci’s large weapon design with multiple gun barrels called?

Leonardo da Vinci’s multiple-barrel weapon design is commonly called the 33-barrel organ.

The design arranged thirty-three small cannons in three rows on a wheeled platform. The nickname “organ” comes from the visual resemblance between the parallel barrels and the pipes of a musical organ. The arrangement was intended to allow one group of barrels to fire while another group cooled or was reloaded.

Leonardo included the concept among his military-engineering studies, which also covered fortifications, bridges, and artillery. The surviving drawing shows a proposed weapon rather than evidence that Leonardo manufactured a battlefield-ready example. Its practical value would have depended on reliable gunpowder, strong barrels, and a workable loading system.

The number 33 is important: it distinguishes this design from other historical volley guns and from later multi-barrel weapons. The 33-barrel organ was not a musical instrument, despite its name, and it should not be confused with a conventional cannon.