In Virginia, Confederate artillery attacks a moving Union troop train and forces its soldiers to detrain and retreat

The First Ohio Volunteer Infantry under General Robert Schenck was reinforcing the Alexandria, Loudon, and Hampshire Railroad line in Fairfax County, Virginia using a railroad train to carry the deploying troops.  Towards the end of the day, near Vienna, Virginia, in what may have been the first engagement of its kind in military history, a small Confederate artillery battery fired on the moving train, killing eight men.  Troops under Colonel Maxcy Gregg then attacked the detraining Ohioans and drove them back along the track on foot. (By John Osborne)