APRIL 5-MAY 4, 1862.-Siege of Yorktown, Va.

SUMMARY OF THE PRINCIPAL EVENTS.

April 4, 1862.-Advance of the Army of the Potomac from vicinity of Fort Monroe.

5, 1862.-Skirmish near junction of the Warwick and Yorktown Roads.

Skirmish near Lee's Mill.

9-11, 1862.-Reconnaissance in front of Yorktown.

16, 1862.-Engagement at Lee's Mill, Burnt Chimneys, or Dam No. 1.

22, 1862.-Franklin's division arrives in York River.

May 4, 1862.-Yorktown occupied by the Union forces.

REPORTS, ETC.

Numbers 1.-Organization of the Army of the Potomac, commanded by Major General George B. McClellan, during the siege of Yorktown.

Numbers 2.-Brigadier General Oliver O. Howard, U. S. Army, commanding First Brigade, Second Division (Richardson's), Second Corps, of operations April 4-7.

Numbers 3.-Brigadier General Fitz John Porter, U. S. Army, commanding division, of operations April 4-6.

Numbers 4.-Brigadier General John H. Martindale, U. S. Army, commanding First Brigade, of operations April 4-7.

Numbers 5.-Colonel Charles W. Roberts, Second Maine Infantry, of operations April 4-13.

Numbers 6.-Colonel James Barnes, Eighteenth Massachusetts Infantry, of operations April 4-14.

Numbers 7.-Colonel Jessee A. Gove, Twenty-second Massachusetts Infantry, of operations April 4-12.

Numbers 8.-Colonel Charles A. Johnson, Twenty-fifth New York Infantry, of operations April 4-13.

Numbers 9.-Brigadier General George W. Morell, U. S. Army, commanding Second Brigade,of operations April 4-9.

No. 10.-Brigadier General William F. Smith, U. S. Army, commanding Second Division, Fourth Corps, of operations April 4-12.

No. 11.-Colonel Hiram Berdan, First U. S. Sharpshooters, of operations April 4-21.

No. 12.-Lieutenant Henry W. Kingsbury, commanding Battery D, Fifth U. S. Artillery, of operations April 5.

No. 13.-Lieutenant Charles E. Hazlett, Battery D, Fifth U. S. Artillery, of operations April 5.

No. 14.-Captain Augustus P. Martin, Battery C, Massachusetts Light Artillery, of operations April 5.

No. 15.-Captain William B. Weeden, Battery C, First Rhode Island Light Artillery, of operations April 5.

No. 16.-Brigadier General John W. Davidson, U. S. Army, commanding Third Brigade, Second Division, Fourth Corps, of operations April 5-12.

No. 17.-Brigadier General John J. Peck, U. S. Army, of operations April 5-30.

No. 18.-Brigadier General Winfield S. Hancock, U. S. Army, of reconnaissance toward Yorktown, April 6, with indorsements.

No. 19.-Brigadier General Fitz John Porter, U. S. Army, as Director of the Siege of Yorktown from April 7-May 5.

No. 20.-Brigadier General John G. Barnard, U. S. Army, Chief Engineer Army of the Potomac, of operations during the siege.

No. 21.-Lieutenant Cyrus B. Comstock, Corps of Engineers, U. S. Army, of Confederate works at Gloucester Point, Va.