men killed, 32 wounded, including three officers, Colonel Burges, of General Sprague's staff, being one of them; also 42 horses killed.

I have the honor to be, very respectfully, your obedient servant,

W. R. PALMER,

Major, Top. Engrs., Brevet Lieutenant-Colonel, U. S. Army.

Brigadier General A. A. HUMPHREYS,

Chief Top. Engr., Army of the Potomac, Williamsburg, Va.

Numbers 3. Report of Brigadier General Philip St. George Cooke,

U. S. Army, commanding Cavalry Division.

HEADQUARTERS CAVALRY DIVISION, Williamsburg, Va., May 7, 1862.

SIR: I have the honor to make for the general commanding-in-chief a report of the action of the advance guard of the army, or that portion of it under my immediate command, at the forts in front of Williamsburg, on the 4th May instant:

The regiments of the division present were but two-Sixth Cavalry, First Brigade, and First Cavalry, Second Brigade. Of Lieutenant Colonel Hays' four batteries of horse artillery, but one, Captain Gibson's, was placed under my command. Having passed Yorktown about 2 miles, you, who I understood were combining the advance on two roads, gave me a general instruction to push on to the junction of these roads near Williamsburg, attacking the enemy at discretion. About 2 miles below Williamsburg my advance guard and flankers encountered a rear guard of the enemy, about two companies, at a defile of a mill and dam and a breastwork across the road. I ordered up a section of artillery, with which Lieutenant Fuller handsomely opened fire at less than 300 yards under a fire of musketry. After a few rounds I ordered the advance guard, Captain Savage's squadron, Sixth Cavalry, to advance and charge, but the enemy had retreated, leaving two military wagons in flames and also a spiked howitzer. During the affair General Emory, who joined me in front, had been ordered by you, as I afterwards learned, with Major Barker's squadron, of my command, to the other road.

On reaching with the head of my column the strip of swampy woods, the central battle-field of the next day, I received a report from Savage's right flank platoon that beyond and to the right there were field works. Halting the column, I sent Lieutenant Martin, acting assistant adjutant-general, to penetrate the woods and assure himself if they were abandoned. Soon after Colonel Palmer, Topographical Engineers, who was with the support of the advance guard, Captain Magruder's squadron First Cavalry, reported that there was an occupied work in front, which he thought the enemy could be driven from by a section of the battery. I moved on. On arriving at the farther edge of the woods, by the narrow muddy road, the enemy and his extensive works were in view. Lieutenant Martin had, however, just returned, and reported the works to the right to be unoccupied, and although there was a considerable force of the three arms in front, I assumed that it was only a rear guard of a few regiments or a legion; that I might by boldness push on, especially as I received a report that there was another forest road which