What type of weapon did Leonardo da Vinci propose with multiple barrels mounted on a rotating platform?

Leonardo da Vinci proposed a multi-barrel cannon mounted on a rotating platform.

The concept belongs to his broader group of military-machine designs and is often discussed alongside his organ gun. Multiple barrels could be loaded before combat, allowing a crew to fire several shots in succession. After firing, the platform could be rotated or the assembly could be repositioned while other barrels were prepared.

This arrangement addressed a familiar weakness of early artillery: loading a cannon took time, leaving the weapon temporarily inactive. Leonardo’s design tried to increase the number of shots available without requiring a separate cannon for every position. It was still a black-powder weapon, so smoke, recoil, barrel heating, and slow reloading remained practical problems.

The design should not be called a modern machine gun. Automatic firearms depend on a repeating loading and firing cycle, whereas Leonardo’s proposal relied on preloaded barrels and manual operation. Nor should it be confused with the organ gun, whose barrels are arranged in a pipe-like array for a volley. The rotating platform is the defining feature here.