HEADQUARTERS ARMY OF THE POTOMAC, April 28, 1862-11 p.m.

Hon. E. M. STANTON,
Secretary of War:

Enemy have fired a good deal to-day, and have done no damage that I have heard of. Silenced one of their batteries near Wynn's Mill to-day. Commenced a battery to-night from right of first parallel to reach position for a heavy battery bearing upon water batteries and Gloucester. Regulars on the work. Enemy have been firing at them; do not know result. Mortar batteries progressing; will soon be ready to open. Would be glad to have the 30-pounder Parrotts in the works around Washington at once. Am very short of that excellent gun.

GEO. B. McCLELLAN,

Major-General.

HDQRS. HOOKER'S DIVISION THIRD ARMY CORPS, Camp Winfield Scott, near Yorktown, Va., April 28, 1862.

Brigadier General S. WILLIAMS,
Adjutant-General, Army of the Potomac:

I have the honor to report that the First Massachusetts Regiment and a part of the Twenty-sixth Pennsylvania Regiment, in all 1,000 men, under Colonel Cowdin, occupied my advanced line of pickets until 6 o'clock this morning. The latter reports that the enemy displayed three or four regiments on his right a little before dark last night. About 11 o'clock he reports considerable musket firing between the advanced pickets on and near the Yorktown road.

I have nothing of importance to report of the supports of Batteries Nos.2 and 3, under Colonel Johnson, Eighth Regiment New Jersey Volunteers.

Very respectfully,&c.,

JOSEPH HOOKER,

Brigadier-General, Commanding Division.

U. S. STEAMER WACHUSETT, York River, April 28, 1862.

Major General GEORGE B. McCLELLAN,

Commanding Army of the Potomac, Headquarters near Yorktown, Va.:

GENERAL: I have reason to believe that the enemy has withdrawn his long-range rifles from Yorktown and has placed them in the woods, to operate on this anchorage. The shells for the two 100-pounder vessels are nearly exhausted,and I am just now advised that a supply vessel may not be expected under three days, and to husband our shells in the mean time.

Should the enemy place rifles behind embankments 900 yards beyond the margin of the river our 11-inch guns could not reach them, their range for accurate firing only 1,320 yards and short of 3,000 yards at extreme elevation, while the 100-pounders, mounted on extremely vulnerable, vessels, with their machinery exposed and with crews as yet unpracticed, and short of shell though with abundance of shot, could do little toward displacing the enemy.

As the first duty of importance for the vessels will be to cover the landing of General Franklin's division, they must be kept intact and