From the Rapidan.
Orange C. H., Dec. 26.
--Gen. Rosser has just completed an entire circuit of the Yankee army, starting from Fredericksburg and entering the Valley at Conrad's Store.--He burnt the bridge over Pope's Head Run, near Sangster's Station, just out from Alexandria, capturing and dispersing the troops left as a guard.
Owing to the high water and bad weather he was prevented from doing more damage.
Gregg's Yankee cavalry pursued, but did not overtake him. Gen. Rosser was forced to swim Bull Run.
His loss was very slight, if any. The enemy, white in pursuit, destroyed two tanneries and a lot of leather at Sperryville, Rappahanock co.; also, two tanneries, a flour mill, and some Government workshops at Luray, in Page county.
They also committed many other excesses, including the taking away of negroes, and shot a Confederate named Smedley, at Washington, Rappahanock county' after he had surrendered.
Parties just out from Culpeper report the enemy to be pulling down all vacant and outhouses in their line, including all churches in order to construct winter quarters.
They are issuing rations to the citizens in Culpeper.
It is said they moved some infantry as far in this direction as Mitchell's Station on Thursday evening, to act as front pickets, to relieve the cavalry to go rearwards to recruit. 