Leonardo da Vinci’s multi-barreled cannon was nicknamed an organ because its parallel barrels resembled the pipes of a musical organ.
The design arranged many small cannon barrels side by side on a frame. Firing several barrels in sequence could increase the weapon’s rate of fire compared with repeatedly loading one barrel, while the arrangement could also distribute shots across a wider area.
The nickname refers to appearance, not to the weapon producing music. Leonardo’s drawing is commonly described as a 33-barreled cannon or a “33-barrelled organ,” although the exact construction and battlefield performance belong to the realm of a design study rather than a proven operational weapon.
This concept is separate from Leonardo’s musical inventions, including a mechanical drum designed to produce continuous rhythms. The organ comparison is specifically associated with the cannon’s grouped barrels.