What multi-barreled firearm did Leonardo da Vinci design to fire repeated volleys?

Leonardo da Vinci designed a 33-barrel organ, a multi-barreled firearm intended to fire repeated volleys.

The weapon arranged 33 small guns in three rows of 11 barrels. Its name comes from the resemblance to the pipes of a musical organ, not from any musical function. The design was intended to let one row fire while another was being loaded, potentially increasing the rate of fire compared with a single cannon.

Leonardo’s drawing appears in his military-engineering studies from the late fifteenth century. Like many of his weapons, the 33-barrel organ was a concept rather than a proven battlefield machine. Coordinating ignition, loading, recoil, and safe operation would have been difficult with Renaissance technology.

It should not be confused with the later organ gun family in general, which includes other volley firearms. The number 33 identifies Leonardo’s particular arrangement of three sets of 11 barrels.