What Leonardo da Vinci design used 33 barrels to fire repeated cannon shots?

Leonardo da Vinci designed a 33-barreled organ to fire repeated cannon shots.

The weapon concept arranged 33 small cannons in three rows of 11 on a supporting frame. The name “organ” refers to the visual resemblance between the parallel barrels and the pipes of a musical organ. The arrangement was intended to let one row fire while another was being loaded or repositioned.

Leonardo’s notes present the design as a military device, but there is no evidence that he built and used a battlefield example. The concept belongs to a broader Renaissance interest in increasing the rate of fire of gunpowder weapons, which were slow to reload individually.

The design is often confused with a machine gun. It did not use a modern automatic firing mechanism or a continuous ammunition feed. It was a multi-barrel artillery arrangement, and the term “organ gun” is the standard historical description for this class of weapon.