road at the Long Bridge. I am glad to report that the two regiments passed the Relay House at 8.30 a. m. and will be due in Washington at or before 11. Our engines will deliver them at the Long Bridge without delay. Three additional regiments left Parkersburg last night, and have passed the threatened point at Rowlesburg, Cheat River, whither General Kelley has gone in person with 1,000 men to meet reported advance of guerrillas. This second convoy of troops will be due at Washington to-morrow.

W. P. SMITH,

Agent Baltimore and Ohio Railroad.

WASHINGTON, August 23, 1862 - 9.45 a. m.

Colonel HERMAN HAUPT, Alexandria:

Is it not of the utmost importance to prevent a great accumulation of power and rolling stock at the outer end of the road? If the enemy should by a sudden dash burn a bridge or set the trains on fire it would, for the time being, put it out of our power to send forward either re-enforcements or supplies.

P. H. WATSON,

Assistant Secretary of War.

ALEXANDRIA DEPOT, August 23, 1862.

Honorable P. H. WATSON,

Assistant Secretary of War:

You are, as usual, perfectly right. It was not the intention to accumulate power at the other end. The orders were, run up, unload, and return immediately to Manassas; there pass trains and proceed to Alexandria. None of the power has yet been returned, and I have not to this time been able to get an answer why.

HAUPT.

ALEXANDRIA DEPOT,

August 23, 1862 - 10.20 a. m.

Honorable P. H. WATSON:

Just received answer from Manassas that none of the engines sent to Catlett's with troops have returned. I have ordered an empty engine to go forward cautiously, ascertain cause of detention, and report.

H. HAUPT.

WASHINGTON, August 23, 1862 - 10.50 a. m.

Colonel HAUPT:

Can you manage in some way to make it understood at the outer end of the road that cars can be used either for transportation or for ware-houses, but not for both? That they can receive re-enforcements and supplies only by returning the cars.

P. H. WATSON.