being found, I was, on my return, directed to post the Twenty-seventh pennsylvania Regiment on the right of the Blackburn Ford road. On returning from the discharge of this portion of my duty I was unable to find general headquarters. I remained with Greene's battery until I was informed that the Army had been ordered to fall back to Fairfax Court-House ad make a stand.

At 3.30 Monday morning I was at Fairfax Court-House with my wagon, ready to carry out such orders as I might receive. The troops continued to file though the town, and I ascertained from Colonel Blenker that new orders had been issued, direction the troops to fall back to their old positions on the south side of the Potomac. I started my wagon and detachment for the engineer depot at Fort Runyon, and, at Colonel Richardson's request, accompanied him and his rear guard of two Michigan regiments. These, I believe, were the last troops that left Fairfax Court-House, and covered the retreat as far as the cross-roads formed by the Alexandria turnpike and road through Arlington Mills. I shortly afterwards ordered an advance, reaching Alexandria about noon on Monday.

Before closing my report I wish to mention Sergeant Field and ten men from the Fourth New Jersey (three months') Volunteers, who accompanied my tool wagon and brought it back in safety, being the most of the time separated from me.

Respectfully submitted.

FREDERICK E. PRIME,

First Lieutenant, Engineers.

Major J. G. BARNARD,

Corps of Engineers, Washington, D. C.

Numbers 10. Report of Captain Henry F. Clarke, Commissary of Subsistence, U. S. Army, of the subsistence of the Ar,y from July 15 to 21.

ARLINGTON, VA., August 2, 1861.

CAPTAIN: For the information of the general commanding the department, I have the honor to submit the following report in reference to the subsistence of the Army under his command during its recent operations in front:

On the 15th ultimo the commanders of divisions were directed to see that all the troops of their respective commands have cooked and in their haversacks by 3 p. m. the next day three days' rations, and orders were given that five days' additional subsistence should e loaded into wagon trains on the day of march, and follow the Army on the day succeeding, and that a specified number of beef cattle should be driven forward with each train.

Owing to the necessary number of wagons not being furnished in season to uninstructed and many worthless teamsters and green teams, and to some of the roads being bad, only on of the trains-that is charge of First Lieutenant J. P. Hawkins, Second Infantry, A. C. S.-was able to overtake the Army on the morning of the 28th. It, with ninety head of beef cattle, by traveling all the previous night, arrived at Fairfax Court-House on the morning stated, before the Army had taken up its march. During the morning, while the Army was moving forward to Centreville, it was thought the other subsistence trains, in charge of First