On Sunday last a clerk in the Signal Service Headquarters informed Mr. Stuart that orders had been issued for the officers of that service to embark that night. Next morning Mr. Stuart observed a vessel in the stream flying the flag of the Signal Service, and evidently awaiting the arrival of the general or further orders.

But these officers always attended the general, and he thinks therefore that they were awaiting him; and, subsequently noting the absence of the vessel, is certain it proceeded down the river, and that General McClellan preceded or accompanied it. His information is to the effect that McDowell's division alone is left to threaten General Johnston; that it is not very strong in numbers and almost without artillery. The forces are scattered about, and a great display made of army wagons, to produce the impression that the force is larger than it really is, and seriously meditates an advance. This Mr. Stuart is satisfied they dare not do, but will limit their operations to amusing our generals and preventing, if possible, their timely re-enforcement of the real point of attack, which he supposes to be the Peninsula. Most of the information on this point was communicated to Mr. Stuart on Wednesday night by an educated and intelligent negro, who had a wife on his lot, and who came down on that day from Manassas with a major in the commissary department, in which also the negro was employed. This informant also told him that the Confederate had driven the Federals from Warrenton back to Manassas, capturing or killing 3 of their most valuable men, officers he supposes were meant; that he had recently been to Manassas, Fairfax, and Centreville, and that he saw no artillery at either place or anywhere else on his route, except one battery, which was on its way to Alexandria to be shipped off. Similar information was conveyed to him by a gentleman employed as a secret agent by General Johnston, who had just come from General Johnston's camp, and was on his way to New York.

With regard to Hooker's division, Mr. Stuart himself saw a number of transports and steamers lying in Mattawoman Creek as the vessel on which he was got off the mouth of it. In a little while three other large steamers came up and joined the rest, and shortly afterward several more appeared in sight. There was a busy movement of troops on shore, evidently preparing for embarkation, and they are supposed to have gone down the river on Friday night.

The foregoing narrative is written out from notes of the conversation taken at the time, and, except being fuller, to make it intelligible to the reader, is an accurate transcript of what was said and noted down.

Respectfully, &c.,

B. B. DOUGLAS,

Captain, Company H, Ninth Virginia Cavalry.

HEADQUARTERS,
Richmond, Va., April 8, 1862.

Honorable S. R. MALLORY,

Secretary of the Navy, Richmond, Va.:

SIR: I have the honor to inform you that, from recent developments of the intentions of the enemy in the Peninsula, it is my opinion that they are endeavoring to change their base of operations from James to York River. This charge has no doubt been occasioned by their fear of the effect of the Virginia upon their shipping in the James. General