which in conjunction with gunboats lying off the prolongation fo the lines afford ample security.

On the east beach the mill has been surrounded with abatis, loop-holed, and otherwise arranged so as to be serviceable for an against musketry and field artillery. The swamp to the front and left has been dikes and overflowed across the approaches leading in west of the swamp. A breast-height has been thrown, embrasure for one gun (12-pounder field howitzer), and flanked by rifle trenches. A line of abatis runs from this point to the cotton-press, the 8-foot fence around which is loop-holed for a rifle trench and platformed for another tier of musketry. The brick wall forming part of the north side has been loop-holed and embrasure for one gun (12-pounder howitzer), which bears up the line of railroad. Abatis connects this point with the rebel Ex-Senator Mallory's house, now the headquarters of Colonel Wilson, the fence around which is loop-holed and trenched, and a gun (12-pounder field howitzer) placed in position on the northeast corner, which flanks the abatis to the east, and also the line of the abatis running up to the redoubt. A stockade crosses the road leading into the town past Colonel Wilson's headquarters.

The redoubt is built on the site of the old Spanish fort San Miguel, an eminence which commands the town and vicinity; is a half bastion, with flanks and wings running back to meet the abatis on each side; is furnished with two 30-pounder Parrott rifles, one 10-pounder Parrott rifle, two 12-pounder field howitzers, and two roomy magazines; is closed at the gorge and flanked by its own fire as well as that from positions occupied within the lines. Abatis runs from this point to the plateau on the west of the town, where another work has been thrown up, commanding the Mobile approaches, and consisting of a ditch and breast-height embrasure for four 12-pounder field howitzers. There is also at this point a battery of two mountain howitzers, to be used as required. From this point to the west beach the line consists of abatis, swamps, and rifle trenches, and is throughout its whole extent arranged for a close flank fire of musketry.

The Fifteenth Maine Regiment now holds the east of the town as far as the cotton-press, which is garrisoned by three companies of the Sixth Regiment New York Volunteers. Colonel Wilson's headquarters are held by two companies of the Sixth; the Lyon house, just northward and within the lines, by one company of the Sixth. There is here a battery of two mountain howitzers, to be used as required. The Hyer house, just in rear of the redoubt, is held by one company of the Sixth. Two companies of the Ninety-first New York are camped between this point and the redoubt, and one company of the Sixth garrisons the redoubt. Four companies of the Ninety-first hold the work on the Mobile plateau, and four companies of the same regiment are quartered on the lines by the bay in the southwest part of the town. My own company, mounted, with a battery of four Napoleon guns, occupies the center of the town.

I am, general, very respectfully, your obedient servant,

HENRY W. CLOSSON,

Captain, Chief of Artillery.

[Indorsement.]

HEADQUARTERS TROOPS IN WEST FLORIDA, Pensacola, September 15, 1862.

Approved, and respectfully forwarded for the information of the General-in-Chief of the Army.