October 16th. The rebel General Stuart crossed the Potomac on the 10th above Williamsport, and has made a most successful raid entirely around our army, recrossing in safety near the Monocacy. He has destroyed immense quantities of material, besides refitting his command, and captured horses enough to nearly remount it, and the country is in consequence in the direst distress. He went as far as Chambersburg, destroying everything in his path, and we sat supinely quiet, and our cavalry, too. Oh for a military genius to take command! Colonel Zook has rejoined us again and assumed command of the brigade. I, of course, go with him, and become acting assistant adjutant general.