The position of the enemy was such that it was not possible to make an attack upon him with any hope of success. His force was estimated at about 12,000 men.

On the 8th instant, I was informed by Major-General Loring that my services were no longer required near Fort Pemberton, and that I might, in compliance with the instruction of the lieutenant-general commanding, return at once to Vicksburg.

I reached Haynes' Bluff yesterday at 1 p. m., bringing with me Holland's regiment and [W. N.] Hogg's battery.

I remain, major, very respectfully, your obedient servant,

DABNEY H. MAURY,

Major-General

Major R. W. MEMMINGER,

Assistant Adjutant-General.

Number 11.

Report of Captain Issac N. Brown, C. S. Navy.

CAMP PEMBERTON,

Tallahatchee River, March 10, 1863. (Received March 12.)

GENERAL: I have to send the little steamer Saint Mary's to Yazoo City, and probably to Snyder's Mill, and General Loring does not send dispatches, from the fact, I believe, of the steamer Sharp's having been ordered down, and which may in fact get ahead of the Saint Mary's.

The enemy in great force are near our works, and will attack perhaps early to-morrow.

It has been raining hard for two days here, which made it very unfavorable for us.

I think, from what I can learn, that twenty-five or more transports and six or more gunboats will be within 5 miles of us to-night. I have but two boats-the Keene and Magenta. I went up the river two days ago on the Parallel (steamer), to get cotton to finish the Magenta. When up 70 miles, I found myself near the enemy, and shifted to the Saint Mary's, to remain and make observations, sending the steamer Parallel the woods and disabled herself, so that, to save falling into the hands of the enemy, I ordered her burned, which was done as the enemy came in sight.

I have never been well pleased with our position here, but hope that we may not have to regret taking it up, rather than concentrating our whole force at Yazoo City.

I beg pardon for trespassing so far on General Loring's department as to speak to you of military matters about which I presume he gives you much more full information than I could do. I have done my utmost against most incomprehensible difficulties to fit out the cotton-clad fleet. The cotton was not on the banks of the river, and the state of the country from overflow prevented hauling it. Besides, I could not get the proper boats for the Tallahatchee for reasons already made known in my late letter to you.

I am, very respectfully,

ISAAC N. BROWN,

Commanding, C. S. Navy.

Lieutenant General J. C. PEMBERTON.