Cannonading on the Potomac.
There was an astounding rumor in circulation yesterday in regard to the movements of the enemy on the Potomac; but the truth of the matter is, as we have ascertained from the best authority, that on the night of the inst., three Federal war vessels came up to the neighborhood of the battery at Aquia Creek and commenced a heavy cannonade upon it, firing shot and shell with great profusion for some two hours. We are happy to learn that ‘"nobody was hurt"’ by this liberal expenditure of Yankee ammunition.