Leonardo da Vinci sketched an organ gun, a multi-barrel firearm arranged on a wheeled platform.
His design used a row of small cannon barrels mounted so they could be fired in sequence. The platform could be repositioned or elevated, and the multiple barrels were intended to increase the rate of fire compared with a single muzzle-loading gun.
The name “organ gun” comes from the visual resemblance between the parallel barrels and the pipes of a musical organ. Leonardo’s version was a proposed artillery device, not a modern machine gun: each barrel still required separate loading, and battlefield operation would have been slow and hazardous.
Leonardo’s military notebooks contain many weapon studies, but surviving drawings do not prove that he built every device. The organ gun is best understood as a late-fifteenth-century attempt to solve the problem of delivering repeated fire from a portable artillery platform.