A Union infantryman, a corporal from Indiana named Barton W. Mitchell, picks up a bundle of three cigars from the ground where the Confederates had previously camped. He puts the cigars in his pocket and glances at the piece of paper: it is none other than a copy of Order No. 191, secretly issued by General Lee on September 9th, detailing troop movements. McClellan is quickly informed, but when he exclaims, “Now I know what to do!” a sympathetic Confederate civilian runs to inform the Confederate rearguard.
