FORT MAY, LEXINGTON, AND FORT BOONE, FRANKFORT, KY.

These works were commenced and considered finished under the direction of Brigadier-General Gillmore, in the spring and summer of 1863, but since July 1, 1864, have been extended. The maps of these defenses will be forwarded as soon as completed. For armament see Appendix B.

DEFENSES OF CAMP NELSON, KY.

The topographical map of these defenses and plans of forts, batteries, and magazines may be seen by reference to Appendix A, its armament by reference to Appendix B.

The following is the report of John R. Gilliss, assistant U. S. engineer, in charge of these works:

The camp is protected on the south and WEST mainly by the high bluff of the Kentucky River, and on the east by Hickman Creek. The defensive works required were a continuous line across the neck of the peninsula thus formed, and detached works at the accessible points of the cliffs of these streams.

MAIN LINE FROM HICKMAN CREEK TO THE Kentucky RIVER (SEE ACCOMPANYING MAP.)

An irregular flat ridge, in front of the large sick containing depot buildings, was selected for the line. The ground for 1,000 yards to the front is undulating, but, excepting scattered sink holes, is entirely swept by the fire from three main forts. Beyond this there is, as shown on the map, a large ravine. It has been proposed to erect an advanced work at point a, commanding this, should a force to build it become available. The line consists of eight forts and batteries connected by an infantry intrenchment. The length of the line is 8,805 feet. The revetment of interior slope is all plank, excepting Battery Pope, which is stone, and a small portion of infantry intrechment, between Forts McKee and Jones, which is of logs. The embrasures of Fort Nelson are revetted with sod, and of Fort Jones and Battery Putnam with palisades, the remainder are revetted with fascines. The infantry intrenchment consists of a breast-work four feet thick, four feet three inches high, with a trench in its rear, two feet deep and ten feet broas. This makes a good military road connecting the works. There is a line of abatis along the entire front of the works. WEST of the Nicholasville turnpike the line is double. The abatis line can, in almost every part, he enfilades at short range by grape and canister, from guns in embrasure. WEST of Battery Pope there is on an average only two feet of earth; under this it is solid rock. This will be a serious obstacle to an enemy advancing by sapping. This prevented digging deep ditches in front of Forts Nelson and Jackson. The ditches were therefore made wide, and filled with cedar abatis underlaid with thorn locust. Detailed descriptions of the forts are not given here as plans of them accompany this report; the following, however, show some of the most important relations each fort bears to the rest of the line:

Battery Hatch assists in protecting ground to the WEST of Fort Nelson. It should have been built 300 feet farther to the left, as shown by the dotted lines at point B. There is now a good approach under the brown of the cliff along a terrace. Timber has been felled across it, but the proposed work should be made.

Fort Nelson is the highest point in the line or its vicinity, and the most important work on the line, not only from its range, commanding the other works, and fire on the main turnpike, but because it is on the summit of a ridge which prevents the fire from Forts Jackson and Taylor from covering the ground to the WEST of its salient. The three embrasures on the east eand and barrette at the salient command all the works to the east as far as Fort McKee.

Fort Jackson is comparatively low, as a line from Nelson to Taylor passes about 15 feet above its crest. This allows Forts Nelson and Taylor to fire over it with safety in protecting each other. The guns on its faces protect the ground to the front while those on the flanks enfilade the abatis line from Fort Nelsonun has some fire into the hollows in front.

Battery Putnam, as interior work commenced by Captain Poe before the works to the east were located. It enfilades the east face of Jackson and will be useful should any of the works or infantry intrenchments to the east be captured.

Battery Pape enfilades a branch of the main ravine in front. Much of the ravine is under direct fire from its two barrettes; the remainder can be reached by curved fire. The two embrasures to the east enfilade abatis and sweep ground in front of Taylor.