Background
Duncan was born in 1833 in Sullivan, Maine, and joined the Navy from Boston.
Duncan was born in 1833 in Sullivan, Maine, and joined the Navy from Boston.
He served during the Civil War as a boatswain"s mate and gun captain on the United States Ship Richmond. At the Battle of Mobile Bay on August 5, 1864, he "fought his gun with skill and courage" despite heavy fire. Duncan was discharged in November 1864, having served a total of six years in the Navy.
As captain of a gun on board the United States.S. Richmond during action against rebel forts and gunboats and with the ram Tennessee in Mobile Bay, 5 August 1864.