HEADQUARTERS,
Savannah, January 19, 1864.

Lieutenant Colonel V. SHELIHA,

Chief Engineer, Department of the Gulf, Mobile:

COLONEL: I am in receipt of your letter of January, describing a plan for establishing a battery to the west of the main channel of entrance to Mobile Harbor, where the water is represented to be 3 1/2 to 9 feet in depth, the plan being to use two square-built iron-clad floating batteries which have been turned over by the Navy Department for the purpose. Such a work is certainly desirable, but I much fear that the difficulties of construction in the manner described will be too great for success. Your two flats, on which the whole structure is to rest, will be unwieldy objects to manage in a seaway, and I fear it will be impossible to sink them as you design, float the two square-built batteries on them, and then maneuver them so as to bring them to the ground where they are to rest. Should all this be accomplished another difficulty presents itself, to wit, the sinking of the whole combined to the bottom, so as to give it stability and at the same time preserve the level and proper relations of the parts. Again, such a restructure resting on a sand bottom will change the currents adjacent in such a manner as to cause a displacement of the sand on which it rests, making the whole unstable and unsafe. By your description the two floating batteries are to be raised entirely out of the water, thus exposing a large surface to any winds that may chance to prevail during the progress of the operation, adding much to the difficulty of maneuvering the flats and batteries connected before getting them to their place as firs indicated.

Notwithstanding the numerous difficulties, which I fully appreciate, I will not interpose a positive objection to the trial, but I do desire that nothing shall be attempted on middle ground, a mile north of Fort Morgan, until the placing of the first battery has been fully tested.

In reference to the redoubts protecting the city on the land fronts, I must advise that you do not go into elaborate and expensive arrangements for flanking these works. Our enemy is not disposed to storm works of moderate profile, if we may judge from the past, and I therefore think it admissible to leave our batteries without perfect flanking fires. Time is important, and works of plain outline should first be built. In regard to the chemin-des-rondes, I will say such arrangements are advantageous to some extent, but these should be left until the redoubts themselves are advanced far enough for the reception of their guns. The wall you speak of as resting on the berm is one of earth. I suppose none of masonry should be built.

The claim of Captain Fremaux for advancement shall be considered in connection with those of others so soon as I am able to return to the bureau at Richmond.

If it is proper, I should say that a number of the captains of the corps have performed services entitling them to superior consideration, and they will come in competition with Captain Fremaux for advancement, as the number of major as authorized by law is limited.

In regard to the exorbitant price for lumber, $75 per thousand, I would say that I hope the commanding general will take the matter

37 R R-VOL XXXII, PT II