guns is designed, with covered approaches or rifle-pits, connecting with the flanks of the work. A covered way have been a valuable addition, and could have been easily made in the first construction. The Commission recommend a platform for the 8-inch howitzer, to be made in the pan-coupe, and a rifled 30-pounder to be placed on the existing platforms, on each of the two short lateral faces; also a battery for field guns upon the spur to the southward; also the moving of the two guns on the gorge to more advantageous positions.

Forts Saratoga and Thayer are minor works, forming connecting links between Forts Bunker Hill and Lincoln. They are both lunettes, with faces of 100 feet, and stockaded gorges. The first furnishes valuable cross-fires upon the approaches to Fort Bunker Hill, and its situation is commanding. It is desirable that at least on rifled gun should be in this work, and a platform for such a gun is recommended to be made at the salient. The heavy guns on the flanks should be moved on to the faces, and field guns placed in embrasures substituted. Melons should be raised on the faces. It is amply provided with bomb-proofs.

Fort Thayer is located to command a spacious ravine, which otherwise would afford an ample cover and convenient approach to an enemy. The useless gun on the west-shoulder angle should be moved to the east face, to increase the fire upon this ravine. A platform for a siege gun should be made on the pan-coupe and platforms for field guns on the flanks, and melons raised on faces. A ditch should be made along the stockade of the gorge.

Fort Lincoln is situated on an eminence, overlooking the extensive valley formed by the Eastern Branch and its tributaries, and commanding the Baltimore turnpike, the railroad, and several minor roads, which, passing through or near Bladensburg, lead into Washington. At the foot of this eminence was fought the battle of Bladensburg. The narrowness of the summit, on which it is situated, is unfavorable to a good trace. The exterior batteries and rifle-pits,however, thoroughly see the ground over which assaulting columns must pass, and the bombproof and magazines, arranged as traverses, protect the long and narrow interior from enfilading fires. A 100-pounder is being mounted in the northeast angle, which will sweep the sector from Fort Slocum around to Fort Mahan. The Commission recommend reversed casemates in the northeast angle of counterscarp and a few additional platforms for guns on the western long face. An additional magazine is in construction. From the fort the ridge runs easterly to the Eastern Branch, about three-fourths of a mile distant. About midway is a half-sunk battery for field guns, connected with the work by a double caponiere. At this point the ridge falls abruptly 40 or 50 feet, and the line is continued by rifle-pits to the extremity, where a powerful battery has just been built, terminating this part of our line. A deep, and for three fourths its length impenetrable, ravine takes its origin near the fort, and runs behind and parallel to this ridge. On the spurs immediately south are two half-sunk batteries for field guns, bearing upon the margins of the Eastern Branch.

Fort Mahan may be considered an advanced tete-de-pont to Benning's Bridge,and commands the valley of the Eastern Branch as far as Bladensburg, as well as the immediate approaches to the bridge. It is situated upon an isolated hill, the steep slopes of which are unseen from the fort and are necessarily defended by external rifle-pits. As long as this work is held, an enemy cannot bring artillery to bear upon the bridge, nor move in force along the road which leads from Bladensburg to the Navy-Yard Bridge. Between this road and that leading