What Renaissance weapon did Leonardo da Vinci design with 33 parallel gun barrels?

Leonardo da Vinci designed a 33-barreled organ with 33 parallel gun barrels.

The weapon was a form of organ gun, a firearm made from multiple barrels arranged together. Leonardo’s design placed the barrels in rows so that several projectiles could be fired in a coordinated sequence or volley. The arrangement could provide a wide spread of fire while allowing some barrels to be loaded before others were discharged.

Its nickname comes from the resemblance between the grouped barrels and the pipes of a musical organ. The weapon remained a design rather than a documented Leonardo-built battlefield device.

It should not be confused with a modern machine gun. The 33-barreled organ relied on separate gun barrels and the technology of Renaissance gunpowder weapons. Leonardo’s drawing is notable for attempting to improve the rate and breadth of fire through organization of multiple barrels.