one. In its location there were many conditions to be fulfilled, more than were reconcilable. There is now a most serious defect, which is, that over the readiest approach of an enemy the ground is not seen beyond 200 or 300 yards. I consider it absolutely necessary to remedy this defect, and it can only be done by building lunettes in advance, which I am now doing, or, rather, about doing.

At the Chain Bridge extensive clearing of woods, rifle-pits, auxiliary batteries, &c., have been found necessary. The most defective part of the line-and it was one the most liable to attack during the recent demonstrations of the enemy-was from the Potomac to Fort Massachusetts. The left was occupied by a cluster of three small works, Alexander, Franklin, and Ripley. The turnpikes from Great Falls, Rockville, and Brookville, uniting at Tennallytown, were commanded by Fort Pennsylvania, and an intermediate point and road was held by Fort De Russy. The country is very broken, and was thickly wooded, the woods having been cleared only in the immediate vicinity of the works. At present the woods have been cleared. Two additional forts, several batteries, have been built and are in progress, and a road of communication is likewise in progress. From Fort Massachusetts to the Eastern Branch the line of forts might be considered complete, though it may be determined to enlarge Fort Slocum. Fort Massachusetts itself, the earliest work of this line, was entirely inadequate to its most important position. It has been extensively enlarged. The country in front of this position was more open than usual, but it has been found necessary to fell large quantities of timber. Rifle-pits and some additional batteries have been constructed. The portion of the lines over the Eastern Branch is the least satisfactory of the whole, particularly that portion from Fort Meigs to Fort Stanton. The topography was very hard to deal with, and, unfortunately, the works were located before the woods were cut. The works, serving very imperfectly the approaches, and surrounded by woods, were nearly indefensible. One of the first measures I took was to order a regiment there for clearing. This was, to a considerable extent, done, but while my attention has been directed elsewhere, the work of clearing has been suspended. As the enemy cannot enter the city from this direction, the object of the works is to prevent him seizing these heights, and occupying them long enough to shell the navy-yard and arsenal. For this, the works must be made secure against assault, and auxiliary to this object is the construction of road by which succor can be readily thrown to any point menaced. Some general remarks will apply to the whole line.

When these works were commenced, neither field nor siege guns could be obtained in any adequate numbers; hence the only resource was to arm them with sea-coast 24's and 32's from the arsenal. It always appeared to me objectionable, and I regret that, even in the absence of other guns, I permitted so many guns of this character to be mounted. These guns can only be used upon the enemy's batteries or troops at a distance. At close quarters, not only are they too unmanageable, but, with all expedients used for protection, they are too exposed to permit the men to stand by the guns. In many of the works, such as Forts Pennsylvania, Totten, Lincoln, &c., the objection is not so strong, as the artillery is mainly intended for distant action. But in others, such as Forts Ripley, Franklin, Meigs, &c., it is a most serious evil. I have not investigated the subject thoroughly, but it is probable that many of these guns should be dismantled; and it is certain that a great many emplacements should be prepared for field and siege guns.