Union troops suffer a heavy defeat at Ball's Bluff on the Virginia side of the Potomac

A reconnaissance-in-force of Massachusetts troops across the Potomac into Virginia was reinforced during the day and at about three in the afternoon a pitched battle broke out.  Confederate troops controlled the high ground and in fighting that lasted until dusk drove the Union troops back down to the river.  More than two hundred Union soldiers were killed, including Colonel Edward D. Baker, U.S. Senator from California and good friend to Abraham Lincoln.  Baker remains the only U.S. Senator ever killed in action.  (By John Osborne)