ENGINEER'S OFFICE,

Pass Cavallo, Tex., April 12, 1864.

Captain J. C. STONE,

Asst. Adjt. General 1st Div., 13th Army Corps:

SIR: I have the honor to submit the following report as to number of men employed and progress made toward completing the defenses of this island for the 11th and 12th April, 1864: One hundred and three men from First Brigade, First Division, reported on the right of exterior line on the 11th instant. These were employed on second lunette. One platform was completed in the salient angle of this work this day. This platform is ready to receive a gun if siege platform be sent with it. One hundred men from the Second Brigade were engaged on left of this line. Eleven teams were employed at exterior line the 11th instant.

One hundred and fifteen men were employed at Fort Esperanza and six teams this day. One platform constructed of inch lumber, using three thicknesses, was laid on the north front. The second platform on this front is ready to receive the flooring. Two hundred and thirty-five men were engaged on the works on interior line the 11th instant. The First Brigade furnished a detail of 94 men for right of exterior line the 12th instant, and the Second Brigade 214 for the left. Seven teams were employed on the right and twelve on the left of this line to-day. Very good progress has been made on the whole line to-day, and with the arrangements as at present I think the entire line will be very nearly complete this week.

It is necessary that I should know whether guns mounted on field or siege carriages, or both, are to be used in these works and in which works the different carriages are to be placed, in order that suitable platforms may be constructed for either. In the first lunette there are two platforms for common field carriages; in the second, one in the salient angle for guns mounted on siege carriages. I have directed one to be constructed for same in second redoubt. The second lunette exterior line and first or second redoubt will be ready to receive the heavy guns any time they may be sent, provided siege platforms come with them. I employed 104 men at Fort Esperanza and eight teams the 12th instant and 236 men on interior line. The flooring of one platform in lunette A of this line is complete; of the other two not, but one of them will be to-morrow. Two guns are mounted in this work. The progress made on this line, as well as on Fort Esperanza, for the past two days has been very good. The platforms in left battery at Bayou McHenry have been laid and the guns mounted.

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

JOHN C. COBB,

Colonel in Charge.

HEADQUARTERS DEPARTMENT OF ARKANSAS, &C.,
Little Rock, April 12, 1864.

Major General FREDERICK STEELE:

GENERAL: Messengers with dispatches from you dated the 7th instant arrived yesterday evening at 4 o'clock. Your directions concerning the forwarding of supplies have been and are being complied with as fast as possible. Upon consultation with General Kimball it was thought best to start the train from Pine Bluff, and rendered