hills; and would not cover the ground in front so well as a more retired line. I therefore propose to go to the river near Hyde's Ferry, indicated on the map. For the defense of this line two works will be required, and two batteries; the first battery on the knoll to the right of Fort Gillem may be a simple structure with contiguous rifle-pits; the next point will require an inclosed work, with bomb-proof block-house and magazines. The next battery, protected by obstacles and stockade; the work on the river-bank strong, with necessary bomb-proofs for its garrison. The line thus constructed will effectually guard Nashville, and will cover the advanced structures and corrals, and will require 3,000 men for garrison in time of attack, supported by 2,000 movable troops and by quartermaster employes, who can throw up rifle-pits; 30,000 men could not probably take Nashville thus defended. The cost of these works will be at least $300,000 at present prices, as nearly as I can judge, aided by the opinion of those who have been superintending works at this point. It is proper to remark that the rocky nature of the soil on the hills makes the works built there very costly. The parapets of Fort Morton, as far as completed, have been built of loose stones covered to a depth of three or four feet with earth; the earth is hauled up the hill. The crown of the hill has been removed by blasting to give the requisite reference. Magazines can only be constructed and drained by heavy blasting operations. I think these works must cost three or four times as much as they would were it possible to construct them, as in the vicinity of Washington, by simply excavating a ditch and throwing up the earth for a parapet. The difficulty is inherent to the limestone formation of this locality. Some of the knolls that I propose to occupy by batteries will probably give sufficient earth for their construction so as to avoid blasting. It will be very difficult in this vicinity to get abatis or material suitable for gabions. You must expect that the works will be costly. I propose to push Forts Morton and Houston to completion, and to modify Fort Gillem. The city can thus be defended by the aid of these forts, and the temporary constructions which the troops can erect against any large raiding party. In the mean time I hope to arrange plans for the proposed structures along the whole line.

Estimated cost of completing the defense of Nashville.

1. Battery on Reservoir Hill. . . . . . . . . . . . . . . . . . . . . . . . . . $ 5,000

2. Works on University Hill. . . . . . . . . . . . . . . . . . . . . . . . . . . 10,000

3. Crest between University Hill and Fort Negley to

sweep. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5,000

4. Modifications of Fort Negley. . . . . . . . . . . . . . k on Casino Hill. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15,000

6. Finishing Fort Morton. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30,000

7. Finishing Fort Houston. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30,000

8. Two batteries between Houston and hill 210, defended

by rifle-pits and stockade block-house. . . . . . . . . . . . . 20,000

9. Work on hill (210 ref.). . . . . . . . . . . . . . . . . . . . . . . . . . . . 40,000

10. Modifications of Fort Gillem. . . . . . . . . . . . . . . . . . . . . . 15,000

11. Battery on knoll to right. . . . . . . . . . . . . . . . . . . . . . . . . 10,000

12. Work on second knoll. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30,000

13. Contiguous battery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10,000

14. Work on river-bank. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20,000

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Total. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260,000

Contingencies, rifle-pits, &c. . . . . . . . . . . . . . . . . . . . . . . . . . 40,000

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Grand total. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300,000

I give this as the probable cost of the system of proposed works, having already informed you that the rocky formation of the hills render the construction of these works very expensive. Many of these works