knowledge, that I am unable, without knowing the general plan of operations, to suggest a concnetration of my corps. Independent of the general plan of operations, I would recommend a concentration of one division in rear and to the left of my headquarters, and two division in rear and to the left of my headquarters, and two divisions on the front, now guarded by Brigadier-General Couch; in which case I could effect nothing without a larger supply of heavy artillery.

If it be true that the enemy have successive lines of defense, beginning with a wet ditch or stream which cannot be filled up, I am unable, until I shall have found a weaker point than I have yet discovered, to recommend anything which supposes an assault in front. If Mulberry Island has been evacuated, as the negroes say (and other appearances indicate that the force there has been recently reduced), we can press sharply upon the enemy from Smith's position, and with some heavy artillery we can threaten and perhaps force a passage on the left while the battering at Yorktown is in progress, and at the same time safely leavyy my corps without material change in its present position.

I make these suggestions for the sole reason that my want of accurate knoweldge of the general plan of operations renders it necessary that I should return a qualified answer to your telegram.

The three contrabands and the minutes of their examination will be sent over with this letter.

I have the honor to be, sir, your most obedient servant,

E. D. KEYES,

Brigadier-General, Commanding Fourth Corps.

[Indorsement.]

APRIL 22, 1862.

General MARCY, Chief of Staff:

GENERAL: I have sent two engineer officers to make a careful examination to-day of the left of our line and I will report this evening.

Respectfully,

E. V. SUMNER,

Brigadier-General, U. S. Army, Commanding.

SPECIAL ORDERS,
HDQRS. ARMY OF THE POTOMAC,

No. 119.
Camp Winf. Scott, near Yorkt'n, Va., Ap'l 21, 1862.

* * * * *

III. The following will be sustituted for paragraph 2, Special Orders, No. 118, April 20, 1862:

The plan of a battery and its location having been determined, the general commanding will designate the division of the army which is to perform the labor of its construction.

The general of the trenches will be responsible that the labor is diligently and industriously rendered and that the plan and instructions of the engineer or officer in charge are rigidly adhered to. The chief engineer will indicate the officer of engineers or artillery charged with the professional responsibility of the construction, giving his name to these headquarters and the general of the trenches. At each headquarters of division an officer will be designated during the siege who will be charged with the special duty of regulating the details of working parties. He will consult daily with the engineer or artillery officer in charge of a construction, and upon his requisition for the detail of laborers will, under the orders of the division commander, furnish the detail. He will be responsible for the intrenching tools of the division,