All that portion of the double line of rifle-pits on the highest part (as pointed out to you) should have been made a fort, and the extension of the pits to the left should have been somewhat retired, so as to be thoroughly flanked by the fort. This idea should be carried out now by converting the space indicated into a fort, raising the paraded (thick enough, probably), and making a ditch. In the northwest angle of this work there should be a howitzer to flank the ground in front of the rifle-pits on the left, and on the west face there should be a 30-pounder Parrott gun to command the plain between the mountain and the Potomac.

I cannot say positively whether the rifle-pits should be extended farther to the left than they now extend, but, if not, it must be made certain that the ground is so impracticable, either naturally o by aid of the fallen timber, that they cannot be turned. As none of the guns now in position see this ground, and it may not be possible to see it from the fort, there should be places prepared for one or two howitzers. The woods down the left slope of the mountain should be felled as far in advance as pointed out. the citadel should be finished according to design.

It may be found easier to make the banquettes of timber than of earth. A gun in the angle of the northeast bastion at A would see the eastern slope of the mountain well. Another at B would see the same slopes south of the work, though perhaps a better place for the latter purpose would be the eminence 100 or 200 yards sough of B. It is intended, I believe, in the design, to have a gun at C. The platform may be made.

There should be a magazine inside this work, and a secure structure, to contain provisions and water-tanks. The magazine outside the citadel should have its doorway corrected or protected.

In the right angle of the external fort (as i propose to make it) should be a platform for a 30-pounder Parrott, so arranged as to fire either to the front, on the capital, or into the valley form below.

The plateau just below and on the right of the stone fort should have rifle-pits arranged along its margin, so as to see the slopes of the mountain thoroughly in every direction. The timber on the E. slope should be felled as far north as I pointed out, and south nearly or quite to the Potomac. As it is, there would be danger that an enemy would find his way up the mountain between the stone fort and the 30 pounder battery. With the timber felled and kept on the ground, a very few men could defend this flank, if skillfully posted and vigilant. Should the timber ultimately be burned off, further arrangements may be necessary.

In conjunction with the defense of the mountain, a half dozen disposable howitzers (mountain howitzers as good as anything probably) would be desirable. I pointed out to you numerous points where they might be required, but where it is not necessary to make any preliminary arrangements.

As to water, it requires examination as to whether the present supply can be increased.

I think the mountain ought to be tenable by 2,000 men, and that not