John G. Nicolay, The Outbreak of Rebellion

“ [150] our skirmishers, guarding well against a flank attack from the direction of the rebels' position, and after a brisk fire which threw the rebels into confusion, carried their position by a charge, driving them from behind some log breastworks, and pursued them into the thickets on the mountain. We captured twenty-one prisoners, two brass six-pounders, fifty stand of arms, and some corn and provisions. Our loss was twelve killed and forty-nine wounded.” He also places the reported burials of the rebels killed at one hundred and thirty-five, with about twenty wounded.

McClellan had moved all his force up to Pegram's front, and was waiting to begin a direct assault when he should learn that Rosecrans had commenced the attack on the rear. But Rosecrans' fight on the very top of Rich Mountain disconcerted the arrangement. The messenger sent to communicate between McClellan and himself rode unsuspectingly up to a rebel picket-guard, and was captured. McClellan waited all day in vain for the rear attack to begin; for when the engagement on the mountain was over, the day was already so far advanced, and Rosecrans' men were so thoroughly worn out with their toilsome ascent preceding the fight, that it was deemed most prudent to go into bivouac on the field of battle. McClellan was not informed of the fight and its result until the following day, July 12th, when it was also ascertained that the whole rebel camp and position had been precipitately evacuated; he was therefore now able, not only to secure their abandoned guns and supplies, but to push without opposition along the turnpike entirely over the mountain and occupy Beverly.

Pegram had, on the 11th, personally gone to the mountain-top-only, however, to witness the defeat and dispersion of his little detachment. Seeing himself thus in a trap, with McClellan in front and Rosecrans in secure possession