The place is inclosed by a strong infantry line 1,600 yards long, with a deep ditch not easily gotten over. The breast-height revetment, in part logs, is very good. Some portion of it was pulled down by the rebels when Decatur was evacuated. The parapet has a high command, entirely covering troops in the rear, and is six feet thick. This line is strengthened by two batteries, with embrasures for fourteen guns each. The larger of these batteries is entirely inclosed, and is properly a redoubt, but it has no magazine, keep, or traverse. The other battery, of more elongated form, has a traverse in the middle and a small block-house on the gorge line, also a leaky magazine. A small additional battery was formed, but never finished for its armament. Embrasures for four guns are distributed at other points of the line, to the right and left. The ground in front of Decatur is very favorable for defense, generally falling very slightly away from the line. There are no elevated points in the vicinity to serve as lodgments for an enemy's batteries. The place is susceptible of resisting a heavy attack. The line rests upon the river at both extremities. A small interior redoubt toward the west portion of the line has been built. Near the center of the inclosed space a large square redoubt was commenced, but it never progressed far enough to be available as a defense. It is probable that Decatur, from the importance of its position, will be permanently garrisoned. The two works therefore should be preserved. The large redoubt requires a magazine, and that in the smaller one should be repaired. In time the infantry line will be thrown down. The garrison should keep the two redoubts in order, and do what is necessary to complete the interior arrangements. Decatur is twenty feet at least above the highest rise of the river, whereas the opposite or north bank is swampy, and a long lagoon parallel to the river makes any attack from this direction difficult. The rebuilding of the bridge across the Tennessee and the completion of the road to Corinth will restore this depot to its former importance. Decatur is a strong, well-defended place. To General R. S. Granger, commanding the District of Northern Alabama, the creditable condition of these works is mostly due.

ATHENS.

Athens is about fifteen miles north of Decatur, on the road to Nashville. It is a small town, but will probably be garrisoned for some months. The fort is on a slight elevation, about half a mile from the depot. It is essentially a bastion-work, having four bastion fronts and the fifth closing with two lines, making a small re-entering angle. It inclose a space about 300 feet long by 200 wide. The parapet is well formed and reverted in part with gabions and in part with wattlings. There are embrasures for thirteen guns. No attention has been given to the subject of defilement. As there are two positions on opposite sides of the fort a few feet higher than its own site, a traverse should have been constructed across it for the protection of the garrison against reverse fire. This is scarcely necessary now. It would be well to put a small magazine within the fort for the preservation of the ammunition of the garrison. One company will doubtless be sufficient to hold Athens. The colonel commanding at this place has kept the fort in good order. By whom it was planned and built I have not ascertained. It is evident that the location of the embrasures was not made by a skilled engineer. It is, however, a creditable work, and ought to stand a heavy attack before yielding.