George B. McClellan to GIDEON WELLES, Secretary of the United States Navy, August 12, 1861

August 12, 1861.

‘ 3 Washington, August 12, 1861. SIR: Ihave to-day received additional information which convinces me that it is more than probable that the enemy will, within a very short time, attempt to throw a respectable force from the mouth of Aquia Creek into Maryland. This attempt will “probably be preceded by the erection of batteries at Mathias and White House Points. Such a movement on the part of the enemy, in connection with otbers probably designed, would place Washington in great jeopardy. I most earnestly urge that the strongest possible naval force be at once concentrated near the mouth of Aquia Creek, and that the most vigilant watch be maintained day and night, so as to render such passage of the river absolutely impossible. ; I recommend that the Minnesota and any other vessels available from Hampton Roads be at once ordered up there, aud that a great quantity of coal be sent to that ” vicinity, sufficient for several weeks’ supply. At least one strong war vessel should be kept at Alexandria, and I again urge the concentration of a strong naval force on the Potomae without delay. If the Naval Department will render it absolutely impossible for the enemy to cross the river below Washington, the security of the capital will be greatly increased. I cannot too earnestly urge.an immediate compliance with these requests. I am, sir,

very respectfully, your obedient servant,

GEO. B. McCLELLAN,

Major-General, Commanding.

It was on the 27th of September, 1861, that General Barnard, chief

engineer, in company with Captain Wyman, of the Potomac flotilla,

– had been instructed to make a reconnaissance of the enemy’s batteries

as far as Mathias Point. In his report of his observations he says:

Batteries at High Point and Cockpit Point, and thence down to Chopawamsic,