I have written to Govrnor Vance begging the employment of his State troops and militia for the defense of the railroad line, so as to leave at least General Martin's brigade free to re- enforce Wilmington,

J. A. SEDDON,

Secretary of War,

[Inclosure.]

HEADQUARTERS DEPARTMENT OF NORTH CAROLINA,
Wilmington, August 31, 1863.

Honorable JAMES A. SEDDON,

Secretary of War, Richmond:

Sir: Suppose the map of North Carolina before you, andallow me to illustrate briefly only a single phase in the condition of Wilmington, and its probable attack or ddefense.

Suppose me without an army, or at most with but a single brigade, a force much larger than I really have at my command. The enemy, after due preparation, of which we may or may not have received notice, lands a strong force at Shalotte, 18 miles from Fort Caswell and 36 from Wilmington, a point much more suitable for his operations and more convenient than Light- House Inlet at Charleston.

Once landed, as I have not the force at hand to fight at once, three courses are open to him, any of which will be demonstrably fatal He can advance on Fort Caswell as he is doing on Sumter, slowly but securely, strengthening always his position and the tenacity of his grip on the land, or, which a bolder foe would do at once, march upon Smithville, take its batteries in reverse, cut off Fort Caswell and shortly destroy it, or march directly upon the city andd in its front, secure from attack by the obstacles of Brunswick River and the Cape Fear, plant his long range guns and at the easy distance of 2 miles destrouy the city, close the river, and turn all the formidable batteries against naval attack, on which so much labor has been expended. All this is not only possible but highly probable. There are besides other lines of attack equally feasible. I use the description of this in particular only to illustrate what I wish to impress, that the whole system of the plan of defense adopted here, the only plan, indeed, which can be successful, depends on th epresence, I might almost say the constant presence, of an army. On that, and that alone, depends the safety of the flanks, and not only that, but on the rapidity and success of the attack of that army rests the safety of Caswell and Fisher, of this the last harbor left to us, and of the city, an important point however considered.

To have this army assemble, but assemble too late, would, it seems to me, only increase the disaster. I hope that nothing here will be left to chance. The assembling a force, and such a force as would undoubtedly be required, will take, in the present condition of our transportation and resources, a long time -time that we cannot afford to lose.

While the rairoads are constantly deterriorating, they are liable also to be cut off daily. I have intimated that a large force is required here.

Let me illustrate by again referring to the map, and suppose the enemy attempting the southerly line of attack. With but a small