What rotating weapon did Leonardo da Vinci sketch with 33 small cannons?

Leonardo da Vinci sketched a 33-barrel organ, a rotating weapon carrying 33 small cannons.

The design arranged the barrels in three rows on a triangular support. When one row was fired, the support could be rotated so another row moved into position. The arrangement aimed to increase the rate of fire compared with loading and firing a single cannon repeatedly.

The name “organ” refers to the visual arrangement of the barrels, which resembles the pipes of a musical organ. It was not a musical instrument. Leonardo’s drawing belongs to his military-engineering studies, in which he proposed devices for artillery, fortification, transport, and siege warfare.

The weapon is often grouped with early multiple-barrel guns, but it is not identical to a modern machine gun. The design still depended on black-powder artillery and manual loading, and there is no evidence that Leonardo’s particular version entered regular service.