Gatling gun Look up Gatling gun at Dictionary.com
1870, named for designer Dr. Richard Jordan Gatling (1818-1903); patented by 1862 but not used in American Civil War until the Petersburg campaign of June 1864 as an independent initiative by U.S. Gen. Ben Butler.
For the first time in this war, the Gatling gun was used by Butler in repelling one of Beauregard's midnight attacks. Dispatches state that it was very destructive, and rebel prisoners were very curious to know whether it was loaded all night and fired all day. ... Gatling, like Mann, has found it very difficult to get fair trials of his gun, and to have it introduced by the War Department, for the Government leaves all such things to the Ordnance Office, and that office is under the control of old fogies, who work by red tape, and who are slow to perceive the value of ordnance improvements, and still slower to introduce them into practice. ["Scientific American," June 18, 1864]