• Confederates withdraw from the vicinity of Washington to take up defensive position near Centreville, but 7th Brigade under Col. Nathan G. Evans remains near Leesburg.
• The Union commander, General George McClellan sends a force from Langley, Virginia up to Dranesville, hoping to force the 7th Brigade to withdraw from the Leesburg area.

• Union signal station on Sugar Loaf Mountain informs McClellan that the Confederates appear to have moved away from Leesburg.
• McClellan sends a message to General Charles P. Stone in Poolesville, suggesting a "slight demonstration" by his division to encourage the Confederates to withdraw.
• Stone sends the 42nd New York Infantry to Conrad's (now White's) Ferry, and has General Willis Gorman advance to Edwards' Ferry send two companies of the 1st Minnesota Infantry across the river. (By evening, this party returns to the Maryland shore.)
• A Union scouting party crosses the river at Ball's Bluff around 1PM and returns at 10PM, reporting that it saw an unguarded Confederate camp about a mile from the river. Stone orders five companies of the 15th Massachusetts Infantry to cross that night and attack the Confederate camp at daylight, with two companies of the 20th Massachusetts crossing to support them.

• By 4AM the crossing is complete, and around 7AM, the Massachusetts companies discover that the "camp" was actually a row of trees sillhouetted along a ridge line.
• Stone orders another crossing at Edward's Ferry as a diversion.
• Confederate forces begin to skirmish with the Massachusetts Infantry near the Jackson house, and additional Confederate and Union forces move to the scene.
• At 10AM, Colonel Edward D. Baker, also a U.S. Senator and personal friend of Lincoln's, arrives at Stone's headquarters and is given command of all troops in the vicinity of Harrison's Island. Baker orders additional units to cross the river and proceeds to Harrison's Island around noon to assist.
• By 2PM, Colonel Baker crosses over to Ball's Bluff to take command. His attempt at an advance is repulsed.
• Around 5PM, Colonel Baker is killed and Colonel Cogswell takes over. A Union attempt to break through and escape towards Edward's Ferry fails. Union forces are driven back to the bluff and Cogswell orders a general retreat, crossing back to Harrison's Island. With only a narrow and steep path back to the river, troops scramble and fall down the bluff to get to the three boats that were ferrying the troops back and forth. Union officers advise the men to throw their weapons in the river and save themselves.
• By 6PM, the last remaining boat is swamped and many Union soldiers attempt to swim over to Harrison's Island, under fire from the Confederate forces. Colonel Cogswell and other Union officers are captured on the Virginia shore.

• Under a flag of truce, a Union burial party crosses from Harrison's Island to Ball's Bluff.
• Union General Lander is seriously wounded in skirmishing on the Virginia shore opposite Edward's Ferry.
• After dark, General McClellan orders all Union troops on Harrison's Island withdrawn to the Maryland shore.

• McClellan orders General Stone to cross to Virginia at Edward's Ferry, but after nightfall orders a withdrawal.

Photos from U.S. Army Military History Institute.

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