Early this morning, I received information which I deemed worthy of attention, that a force of enemy's cavalry, numbering 300 or 400 men and four mountain howitzers, were moving in the direction of Greenville, evidently with the intention of striking this road. I immediately thought Tarborough, 15 miles east of our main line, was their first point of attack, or rather destruction, for there was nothing to attack but women and children.

At 7. 30 a. m. I received a dispatch from Rocky Mount, from the conductor of the Tarborough branch train, that he had left Tarborough at 3 a. m., and at daylight the cavalry (Third New York) had occupied the town.

At 8. 45 a. m. the line suddenly parted, stopping all telegraphic communications north of Wilson. About 1 p. m. I received a dispatch from Wilson that the brigade over the Tar River, near Rocky Mount, was burned; also Battle cotton factory, at the same place; and the cavalry reported moving in the direction of Wilson. I trust this last move in the direction of Wilson and Contentnea Creek Bridge will be repelled by Colonel [Stephen D.] Pool, reported to be at Wilson. It seems to me, general, that the time has fully arrived for the Government to take some efficient steps to defend the line of this road, if the road, at all times so important to the defense of the country, and especially the Atlantic frontier, is to be maintained. This raid of 300 or less mounted men, and the one of the 5th instant on the road at Warsaw, might easily have been repelled by a small cavalry force and a few companies of infantry, with a few guns at two or three central points in advance of the line of this road. I cast censure upon no one, and least of all upon you, who have but very recently assumed command of the department. Blame does rest on some one, however, for since January and before (with few days of exception), no troops have been held at Tarborough, a very important depot of Government supplies, that 20 mounted and armed men could have destroyed by a raid from Washington at any time. Greenville is the point of departure for cavalry. It is 25 miles from there to Tarborough, and 37 miles from that place to Wilson, on the main road. We want 1, 000 cavalry along the line of this road, that can be relied upon, and we can then maintain our line; otherwise not. I write hurriedly, as I leave in half an hour for the scene of the raid to-day.

I am, general, respectfully,

S. L. FREMONT,

Chief Engineer and Superintended.

Major General W. H. C. WHITING,

Commanding Department of North Carolina.

[Indorsement No. 1.]

HEADQUARTERS,
Wilmington, July 21, 1863.

This letter is respectfully forwarded merely as additional evidence of the great need of cavalry along so long a line. The facts stated by Colonel Fremont are all verified. There have been no troops at Tarborough. I have not yet been able to ascertain all the disposition made by my predecessors. General [J. G.] Martin informed me by telegraph of this raid hav-