The division of General Sedgwick arrived on the morning of the 7th and were landed in the same manner during that day.

Finding our landing deficient in depth of water for a permanent depot for supplying the army, I examined the Pamunkey River during the next day, with a view of selecting a spot higher up, where we could make better wharf accommodations. For our immediate wants I selected Eltham, a point on the right bank of the Pamunkey, some 6 or 7 miles above its mouth.

The following day I reconnoitered the roads leading to it and from it, and commenced the construction of two temporary wharves. In the courses of the day Colonel Ingalls and Colonel Clarke arrived with some of the quartermaster's and commissary transports.

On the 10th I received instructions from General McLellan through General Franklin to proceed up the river as high as Cumberland, and report as to the possibility of carrying our transports to that point With two gunboats and a steamer we proceed up the river to an island some few, miles below Cumberland. Here we found the river obstructed by a line of sunken vessels extending from the island to either shore. The obstructions looked formidable, but a short reconnaissance in boats showed that we could pass with our vessels between two of the sunken vessels. We did so, and then anchored for the night.

Next morning, just at sunrise, we reached Cumberland, where we found General Stoneman had arrived the night before. The examination showed that there was sufficient water for our light transports as far up as Cumberland, and that we could easily make wharves there. I accordingly sent back Captain Arnold, of the artillery, to report to this effect. Learning here some particulars that led me to suppose we might go still higher up the river, I determined to proceed to White House, where the railroad from West Point to Richmond crosses the Pamunkey River. We reached there early in the day, and finding that General Stoneman had thrown forward a squadron of cavalry to that place, I was enabled to go on shore and make such a thorough examination as induced me to believe that this was the proper spot for our final depot of supplies. Deeming this information of great importance, I took the lightest-draught steamer and returned to Eltham the following night, and early next morning reported to General Franklin the result of my observations.

During the day (the 12th) I joined the army on the march towards Cumberland, and reported in person to General McLellan, when he reached that place on Tuesday, May 13.

Very respectfully, your obedient servant,

B. S. ALEXANDER,

Lieutenant-Colonel of Engineers.

Brigadier General J. G. BARNARD,

Late Chief Engineer Army of the Potomac.

CAMP NEAR HARRISON'S LANDING,

July 12, 1862.

SIR: The following is a short statement of the operations upon which I have been engaged since I last submitted a report to you. Events have been so crowded that I have found it impossible to report at an earlier day:

On Thursday, June 26, I laid out a battery for thirty guns on the