From Fredericksburg.
The enemy, whose whole force is believed to be on the opposite side of the river from Fredericksburg had not entered the town up to 1 o'clock yesterday. The train which left this city yesterday morning stopped when within about a mile of the town, when a fire was opened upon it from the opposite bank of the Rappahannock. Fortunately no injury was done, and the train returned here in the afternoon. The fire was not returned by our troops, still in possession of the town.