FREDERICK, MD., December 18, 1861-12 m.

Colonel Leonard reported last night and again this morning at 6.30 a threatened attack on Dam Numbers 5. by Jackson in force with boats. He thinks he is strong enough to protect it.

Have cautioned him not to withdraw attention from position by General Kelley, as this may be cover to other movements. [I] do not leave Frederick on this account.

N. P. BANKS,

Brigadier General S. WILLIAMS.

FREDERICK, December 18, [1861]-10 p.m.

Colonel Leonard reports enemy in position at Falling Waters.

Firing all day, but no loss on our side. Four regiments on the river between Hancock and Shepherdstown, with eight guns. Two regiments and two guns en route to-night. Citizen of Baltimore from Richmond reports that Richmond paper Saturday stated that orders had been given for destruction of canal, thinking it essential to Washington. Perfect quiet at all other points.

N. P. BANKS,

Brigadier-General WILLIAMS.

FREDERICK, December 19, 1861-10 o'clock.

Enemy began cannonading Dam Numbers 5 this morning. No damage. They have not appeared at Dam Numbers 4. They commenced shelling our camp at Point of Rocks this morning, but were driven back at once. Force probably from Leesburg. Nothing important occurred during the night.

N. P. BANKS.

General WILLIAMS.

FREDERICK, MD., December 19-6 p.m.

Heavy firing most of the day at Dam Numbers 5. Enemy driven from the dam. Several killed. Skirmishing at Falling Waters, opposite Williamsport. No loss reported on our side. No serious impression made upon the dam.

Thirty-ninth Illinois guarding the river at Hancock, under Kelley; all quiet, and at Romney at last advices. Captain Best went up to-day for direction of artillery.

N. P. BANKS.

General WILLIAMS.

FREDERICK, MD., December 20, [1861].

Three o'clock p.m. enemy withdrawn from Dam Numbers 5. All quiet there. Mill burnt by our men, who crossed over and returned with lot blankets, entrenching tools, &c.; dam but little injured; will be repaired at once. At Falling Waters enemy's camp shelled last night, but few seen this morning;it is believed they have retired.

N. P. BANKS,

Major-General, Commanding Division.

General WILLIAMS.