HEADQUARTERS ARMY OF THE POTOMAC

August 29, 1862 - 10 p. m. (Received 11 p. m.)

General J. G. BARNARD:

One of my staff officers reports:

I have inspected Forts Thayr, Saratoga, Bunker Hill, Slemmer, and Totten; all in good order and well supplied with ammunition; each garrisoned by one small company of One hundred and twelfth Pennsylvania Volunteers.

The garrisons of all were under marching orders this morning. I think that instead of these works being abandoned they should be occupied with much larger garrisons, and I am at a loss to comprehend where the troops could do better service in defending the approach to Washington.

GEO. B. McCLELLAN,
Major-General.

ALEXANDRIA, August 29, 1862 - 10.20 p. m.

General MARCY, Chief of Staff:

Captain Ferguson is working all the men he can use to advantage, and will start the wagon train at 1 o'clock to-night if the guard is ready. I have sent the orders to General Tyler, and am going in a few moments with Captain Ferguson to see him about the guard. Colonel Haupt will start at 4 a. m. to-morrow the construction train and one forage train and one commissary train for Sangster's Station. The roads from there to Centreville are said to be very good.

A teamster from Pope's command reports his headquarters to-night on Bull Run, 2 miles from Centreville. But 10 wagons of Colonel Holabird's train are loaded, and will go with Captain Ferguson's train, making about 90 wagons in all.

WM. F. BIDDLE,

Captain and Aide-de-Camp.

WASHINGTON, August 29, 1862 - 11.30 p. m.

Major General GEORGE B. McCLELLAN, Alexandria:

There are no instructed artillerymen whatever, except a few employed in teaching raw troops, in the forts from Franklin to Pennsylvania.

I regard these works as liable to attack, and on being relieved by the Fourteenth Massachusetts the garrisons you mention are ordered to preceded to them and to strengthen Ethan Allen and Marcy.

J. G. BARNARD,

Brigadier-General.

P. S. - I could wish that there were still more force north of the Potomac, near the works mentioned and beyond, for I do not feel secure against a crossing of the Potomac above.

WASHINGTON, August 29, 1862.

[General HALLECK]:

I telegraphed General McClellan, explaining the removal of certain garrisons, and said:

I would desire still more troops in or near these works (north of Potomac), for I