Leonardo da Vinci designed an organ gun, a multi-barreled weapon arranged so that several guns could fire in sequence. The name comes from the resemblance of the parallel barrels to the pipes of a musical organ.
His design belongs to a family of proposed rapid-fire artillery devices. Multiple barrels could increase the number of shots delivered before the weapon needed to be reloaded, while a carriage could help crews move and aim it. The concept was aimed at improving battlefield firepower rather than creating a modern automatic firearm.
The organ gun should not be identified with a machine gun. It still relied on separate gunpowder charges and projectiles, and Leonardo's surviving drawings do not prove that a fully operational version was built by him. Similar multi-barreled weapons existed in later military history, but Leonardo's design is notable for its organized array of barrels and its attempt to combine mobility with concentrated fire.