General Stone, commanding Union forces on the Maryland side of the Potomac sent 2 Massachusetts regiments across the river at Harrison's Island, near Leesburg, to harry Joe Johnson's Confederates, who were thought to be evacuating Leesburg itself. They scaled the high, wooded Virginia bank at Ball's Bluff, but found themselves hemmed in and trapped by four regiments of Mississippians and Virginians under 'Shanks' Evans who allowed them to walk into the trap, then forced them, literally, right back over the bluff and into the Potomac. One of the most prominent casualties was the Union Colonel Edward Baker, Senator for Oregon and personal friend of Pres. Lincoln.