American Civil War Confederate LeMat revolver, USA 1855.

The LeMat revolver was a .42 or .36 caliber cap & ball black powder revolver invented by Dr. Jean Alexandre LeMat of New Orleans, which featured a rather unusual secondary 16 gauge smoothbore barrel capable of firing buckshot, and saw service with the armed forces of the Confederate States of America during the American Civil War of 1861–1865.