USS Monongahela pictured c1864, was a barquentine–rigged screw Sloop-of-War that served in the Union Navy during the American Civil War. Her task was to participate in the Union blockade of the Confederate States of America.
Configuration of typical brig-sloop. In the 1770s, the two-masted sloop re-appeared in a new guise as the brig sloop. The successor to the former snow sloops, brig sloops had two masts while ship sloops continued to have three (since a brig is a two-masted, square-rigged vessel and a ship is a square-rigger with three or more masts, though invariably only three in that period).
USS "Hartford", a sloop-of-war, steamer, was the first ship of the United States Navy named for Hartford, the capital of Connecticut. Hartford was launched 22 November 1858 at the Boston Navy Yard and commissioned 27 May 1859, Captain Charles Lowndes in command. "Hartford" served in several prominent campaigns in the American Civil War as the flagship of David G. Farragut, most notably the Battle of Mobile Bay in 1864.