Civil war cannon?

This piece was the most popular smoothbore cannon used during the war. It was named after Napoleon III of France and was widely admired because of its safety, reliability, and killing power, especially at close range. It was the last cast bronze gun used by an American army. The Federal version of the Napoleon can be recognized by the flared front end of the barrel, called the muzzle-swell, whereas Confederate-manufactured Napoleons had straight barrels.