Ribauldequin or Organ Gun (or Medieval Mitrailleuse)
A late medieval volley gun with many small-caliber iron barrels set up parallel on a platform, in use during the 14th and 15th centuries.
The first known ribauldequin was used by the army of Edward III of England in 1339 in France during the Hundred Years’ War. They were also used in the Italian Wars and in the War of the Roses.
image: Organ gun in the Bellifortis treatise (ca. 1405)