What type of weapon did Leonardo da Vinci design with multiple gun barrels?

Leonardo da Vinci designed a multi-barrel cannon with several gun barrels arranged in parallel.

Leonardo’s military notebooks include a weapon often described as a triple-barrel cannon or organ gun. Its barrels were mounted on a wheeled frame, allowing one group to fire while another was being reloaded. The arrangement aimed to increase the speed of artillery fire and reduce the delay between shots.

The weapon was not a modern machine gun. Each barrel still required loading and ignition, and the design’s practical battlefield performance would have depended on heavy equipment, unreliable gunpowder, and trained crews. Leonardo’s multi-barrel concept is best understood as an attempt to solve the problem of slow artillery reloading, not as proof that he invented fully automatic firearms.