Troops of the Army of the Potomac sent to the Peninsula in March and early in April, 1862.

1st. Cavalry reserve, Brigadier General P. St. G. Cooke.-Emory's brigade: Fifth U. S. Cavalry; Sixth U. S. Cavalry; Sixth Pennsylvania Cavalry. Blake's brigade: First U. S. Cavalry; Eighth Pennsylvania Cavalry; Barker's squadron Illinois cavalry.

2nd. Artillery reserve, Colonel Henry J. Hunt; Graham's battery (K and G), First U. S., six Napoleon guns; Randol's battery (E), First U. S., six Napoleon guns; Carlisle's battery (E), Second U. S., six 20-pounder Parrott guns; Robertson's battery, Second U. S., six 3-inch ordnance guns; Benson's battery (M), Second U. S., six 3-inch ordnance guns; Tidball's battery (A), Second U. S., six 3-inch ordnance guns; Edwards' battery (L and M), Third U. S., six 10-pounder Parrott guns; Gibson's battery (C and G), Third U. S., six 3-inch ordnance guns; Livingston's battery (F and K), Third U. S., four 10-pounder Parrott guns; Howe's battery (G), Fourth U. S., six Napoleon guns; De Russy's battery (K), Fourth U. S., six Napoleon guns; Weed's battery (I), Fifth U. S., six 3-inch ordnance guns; Smead's battery (K), Fifth U. S., four Napoleon guns; Ames' battery (A), Fifth U. S., six (four 10-pounder Parrott and two Napoleon) guns; Diedrich's battery (A), New York artillery battalion, six 20-pounder Parrott guns; Voegelie's battery (B), New York artillery battalion, four 20-pounder Parrott guns; Knieriem's battery (C), New York artillery battalion, four 20-pounder Parrott guns; Grim's battery (D), New York artillery battalion, six 32-pounder howitzer guns; total, 100 guns.

3rd. Volunteers engineer troops, General Woodbury: Fifteenth New York Volunteers, Fiftieth New York Volunteers. Regular engineer troops, Captain Duane: Companies A, B, and C, U. S. Engineers. Artillery troops, with siege trains; First Connecticut Heavy Artillery, Colonel Tyler.

4th. Infantry reserve (regular brigade), General Sykes: Nine companies Second U. S. Infantry, seven companies Third U. S. Infantry, ten companies Fourth U. S. Infantry, ten companies Sixth U. S. Infantry, eight companies Tenth and Seventeenth U. S. Infantry, six companies Eleventh U. S. Infantry, eight companies Twelfth U. S. Infantry, nine companies Fourteenth U. S. Infantry, and Fifth New York Volunteers, Colonel Warren.

SECOND CORPS, GENERAL SUMNER.

Cavalry.-Eighth Illinois Cavalry, Colonel Farnsworth, and one squadron Sixth New York Cavalry.

RICHARDSON'S DIVISION.

Artillery.-Clarke's battery (A and C), Fourth U. S., six Napoleon guns; Frank's battery (G), First New York, six 10-pounder Parrott guns; Pettit's battery (B), First New York, six 10-pounder Parrott guns; Hogan's battery (A), Second New York, six 10-pounder Parrott guns.

Infantry.-Howard's brigade: Fifth New Hampshire, Eighty-first Pennsylvania, and Sixty-first and Sixty-fourth New York Volunteers. Meagher's brigade: Sixty-ninth, Sixty-third, and Eighty-eighth New York Volunteers. French's brigade: Fifty-second, Fifty-seventh, and Sixty-sixth New York and Fifty-third Pennsylvania Volunteers.

SEDGWICK'S DIVISION.

Artillery.-Kirby's battery (I), First U. S., six Napoleon guns; Tompkins' battery (A), First Rhode Island, six (four 10-pounder Parrott and two 12-pounder howitzer) guns; Bartlett's battery (B), First Rhode Island, six (four 10-pounder Parrott and two 12-pounder howitzer) guns; Owen's battery (G), six 3-inch ordnance guns.

Infantry.-Gorman's brigade: Second New York State Militia, Fifteenth Massachusetts, Thirty-fourth New York, and First Minnesota Volunteers. Burns' brigade: Sixty-ninth, Seventy-first, Seventy-second, and One hundred and sixth Pennsylvania Volunteers. Dana's brigade: Nineteenth and Twentieth Massachusetts, Seventh Michigan, and Forty-second New York Volunteers.

NOTE.-Blenker's division detached, and assigned to the Mountain Department.

THIRD CORPS, GENERAL HEINTZELMAN.

Cavalry.-Third Pennsylvania Cavalry, Colonel Averell.

PORTER'S DIVISION.

Artillery.-Griffin's battery (D), Fifth U. S., six 10-pounder Parrott guns; Weeden's battery (C), Rhode Island; Martin's battery (C), Massachusetts, six Napoleon guns; Allen's battery (E), Massachusetts, six 3-inch ordnance guns.