What weapon did Leonardo da Vinci design with several gun barrels arranged together?

Leonardo da Vinci designed a multi-barrel cannon with several gun barrels arranged together.

The arrangement was intended to increase the rate of fire compared with a single barrel. While one group of barrels was being loaded or cooled, another might be used, depending on the exact design. Leonardo’s military notebooks contain several studies of artillery and other weapons, so the drawings do not represent one standardized weapon model.

The weapon is sometimes called an organ gun because its parallel barrels resemble the pipes of a musical instrument. That comparison should not be confused with Leonardo’s musical inventions; the barrels were firearms, not sounding pipes. The design also predates modern machine guns, which use later mechanisms for repeated firing.

Leonardo’s multi-barrel concept shows his interest in solving practical battlefield problems through arrangement and timing. Like many of his weapons, it survives primarily as a design study rather than as a documented battlefield invention.