Mitrailleuse
A mitrailleuse (; from French "mitraille", "grapeshot") is a type of volley gun with multiple barrels of rifle calibre that can fire either multiple rounds at once or several rounds in rapid succession. The earliest true mitrailleuse was invented in 1851 by Belgian Army captain Fafschamps, 10 years before the advent of the Gatling gun. It was followed by the Belgian Montigny mitrailleuse in 1863. Then the French 25 barrel ""Canon à Balles"", better known as the Reffye "mitrailleuse", was adopted in great secrecy in 1866. It became the first rapid-firing weapon deployed as standard equipment by any army in a major conflict when it was used during the Franco-Prussian War of 1870–71. A steel block containing twenty-five 13 mm (.51 calibre) centre-fire cartridges was locked against the breech before firing. With the rotation of a crank, the 25 rounds were discharged in rapid succession. The sustainable firing rate of the Reffye mitrailleuse was 100 rounds per minute. The maximum effective range of the Reffye "mitrailleuse" was about 2000 yards; a distance which placed their batteries beyond the reach of Prussian Dreyse needle rifle fire. Reffye mitrailleuses were deployed in six gun batteries and were manned by artillery personnel. They were not infantry support weapons, but rather a form of special artillery.
Mitrailleuse
Several variants of the mitrailleuse concept were developed, with common elements to all of their designs. They were characterized by a number of rifled barrels clustered together and mounted on a conventional artillery chassis or (in the case of one model) a tripod. The ammunition was secured in a single block and placed into the breech, behind the open ends of the barrels. All of the barrels were loaded simultaneously by a manual closing lever or large horizontal screw. A second lever could be worked rapidly (or in some models, a crank could be turned) to fire each barrel in succession. This earned the weapon its French nickname of "moulin à café" (coffee grinder). (A very similar name was earned by the hand-cranked, mechanically loaded, continuous-firing, "coffee mill gun" in America during the American Civil War.)