working parties as the tools available will permit to perform the wok laid out by the engineer officers.

It is a matter of vital importance that the details should be furnished and the work done in the shortest possible time.

I have taken all the necessary steps to have your command relieved by new troops at the earliest practicable moment.

It is imperatively necessary that the work required should be pushed with the utmost vigor. You will be held responsible that this work is pushed with all the rapidity possible with the means at your command, and hold your command in readiness to move at the shortest notice.

If you judge it necessary, send two regiments or an entire brigade of infantry to Williamsburg to cover your operations.

Please push as far as possible the instruction of the old garrison in heavy artillery practice, and give me in full your views as to the best method of holding Williamsburg and the force necessary for that purpose.

Send a couple of squadrons of cavalry to Gloucester to patrol and examine the country on the left bank of the York.

If you think it advisable, send a much larger force of cavalry there for temporary duty. While we have a large cavalry force comparatively idle it may be well to occupy a large portion of it in clearing out the country on that side of the York River.

If you think it best to occupy a point near Williamsburg by infantry, hold Fort Magruder and destroy the adjacent works.

Very respectfully, your obedient servant,

GEO. B. McCLELLAN,

Major-General, Commanding.

FALMOUTH, August 26, 1862.

(Received 2.40 p. m.)

Major-General HALLECK:

Please inform me when you can send say 5,000 new troops to Yorktown. If they can be supplied within three days can order forward Couch's division, now at Yorktown, with the means of transportation at our disposal. Your reply involves the question of retaining or discharging several large transports, for which we are paying a high price. I shall be glad to have your answer at once, as I propose returning shortly to Aquia Creek, proceed thence to Alexandria.

GEO. B. McCLELLAN,

Major-General.

WASHINGTON, August 26, 1862.

Major-General McCLELLAN, Falmouth:

Five thousand new troops can be sent to Yorktown as soon as you can spare transports for that purpose. They can be embarked at Alexandria.

H. W. HALLECK,

General-in-Chief.