MOBILE, February 29, 1864.

Six mortar-boats, three gun-boats off Fort Powell. Firing renewed this morning. One gun-boat, the Jackson, has been withdrawn on account of injuries. Admiral Buchanan and his fleet gone down into the lower bay. Tennessee expected to get down today. No indications of land attack.

D. H. MAURY,

Major-General.

Honorable J. A. SEDDON.

HEADQUARTERS DEPARTMENT OF THE GULF, Mobile, Ala., March 3, 1864.

MY DEAR SIR: I have kept you informed by telegraph of all events of interest in this department.

I am glad that before receiving your dispatch directing me to operate against Sherman I had sent General Cantey with a brigade up the Mobile and Ohio Road, with orders to attack and drive back any raiding party and to delay and obstruct Sherman's advance, if it should be found he was really advancing on Mobile by that route. I held re-enforcements ready for General Cantey. I sent this force up at the very earliest moment possible.

The trains with Government stores which were being round down to Mobile made the movement too late to prevent the destruction of the bridge at De Soto; but so soon as the enemy learned of Cantey's advance they retreated hastily toward Meridian, as I expected. General Cantey reported that the force which had been coming down this way was only a raid. I took immediate measures to repair the road, but the injury done to it is very great. Major Whitfield, of the quartermaster's department, and Mr. Fleming, superintendent of the Mobile, and Ohio Railroad, exhibited a great deal of energy, capacity, and courage in saving the valuable rolling-stock and the Government stores along the road.

For seventeen days the enemy's fleet has been attacking Fort Powell. In that time near 2,000 shot and shell have been thrown at the fort without doing any injury to it which has not been repaired each night by a few hours' work.

Lieutenant-Colonel Williams, commanding, a very gallant and energetic officer, was contused by a fragment of shell; 4 others of the garrison [privates] were slightly wounded, and 1 private killed. There have been no other casualties.

The fort is stronger than on the first day. I have placed batteries on Little Dauphin Island and on Cedar Point.

The fleet is much interrupted in its operations by shoal water and by rough weather. When it resumes the attack I hope the fire of the fort will be more effective than it has yet been. Two of the enemy's boats have been towed off disabled. The present attack does not seem very formidable. If the Tennessee and Nashville can get into the lower bay I believe the enemy will not be able to enter it. The engineers have not yet been able to establish the battery in the channel between Morgan and Gaines.

In making transfers from the Army to the Navy I respectfully suggest that the organizations from beyond the Mississippi be not subject to such transfers, and that only a certain ratio of each organization be transferred. I suggest that the conscript officers here be