Leonardo da Vinci designed an organ gun with multiple barrels arranged to fire in succession.
His famous design used a row or cluster of small gun barrels mounted on a frame. The arrangement resembled the pipes of a musical organ, which is why the weapon is commonly called an organ gun. By preparing several barrels, a crew could produce repeated shots more quickly than with a single manually reloaded gun.
The design is often loosely called a machine gun, but that modern term can be misleading. Leonardo’s weapon did not have the continuous automatic firing mechanism associated with modern machine guns. Its practical advantage came from having many loaded barrels and rotating or repositioning the frame.
The organ gun belongs to Leonardo’s military engineering studies. As with many of his weapons, surviving drawings show an ambitious concept, while firm evidence of widespread production or battlefield use is lacking.