US Civil War steam frigate. Sailors manning the yards of a steam frigate (with paddle wheel) at the Washington Navy Yard, Washington DC, USA, during a visit by Abraham Lincoln, the President of the USA. Lincoln, leading the Union side during the US Civil War (1861-65), visited the Washington Navy Yard on 15 January 1863 to meet with Admiral John Dahlgren and to observe the testing of new weapons. The visiting party's boat and a Union flag are at lower right. Photographed by US Civil War photographer Alexander Gardner (1821-1882) in January 1863. Steam frigates were a transitional warship stage between sail and steam.