Keywords: US Navy 031021-O-0000B-001 In this Mathew Brady photograph, a nine-inch Dahlgren gun on a slide-pivot mounting is seen in operation aboard a U.S. Navy warship during the Civil War.jpg en Navy Historical Center -- In this Matthew Brady photograph a nine-inch Dahlgren gun on a slide-pivot mounting is seen in operation aboard a U S Navy warship during the Civil War A similar gun originally mounted on the famous Confederate ironclad CSS Virginia was recently loaned to the Fredericksburg Area Museum Fredericksburg Va for a three-year exhibit On March 9 1862 CSS Virginia battled the Union ironclad USS Monitor in the famous Battle of Hampton Roads an action in which the two ships fought to a virtual draw and revolutionized sea warfare U S Navy file photo RELEASED 031021-O-0000B-001 Navy http //www navy mil/view_image asp id 10147 U S Navy photo PD-USGov-Military-Navy American Civil War photographs by Mathew Brady Dahlgren guns Ships in the American Civil War |