Caption: Major-General [George B.] McClellan, Commanding the Troops Now on the Potomac. From a photograph. See page 2
Source: Illustration from New York Illustrated News, August 12, 1861, page [225].
Note: Harper's Weekly carried a portrait of General McClellan in their August 3, 1861 issue, as well as an image of McClellan with senior staff members on August 24, 1861.