keeping up connection, when possible, by a line of mounted men and marching as far as Ashby's Gap. These regiments were ordered to return across the country to the pike near Philomont and watch the mount of the valley until the return of the columns from the Potomac, making dispositions to captured or destroy any guerrillas who might be moving in advance of these columns.

In all these movements the orders from army headquarters were most fully carried out; the country on every side of the general line of march was in every instance swept over by flankers from the columns, and in this was the entire valley was gone over. The guerrillas were exceedingly careful to avoid any encounter with any of the parties, even the smallest, that were out on this duty. Efforts were made torn them down or capture them by stratagem, but these in most instances failed. The sides of the mountain bordering Loudoun Valley are practicable throughout their entire extent for horsemen, and the guerrillas, being few in numbers, mounted on fleet horses and thoroughly conversant with the country, had every advantage of my men.

I transmit herewith reports of brigade commanders, as also tabular statements of the destruction done and cattle driven off. Large numbers of the cattle were destroyed or consumed. Most of the fatted hogs were destroyed on the march to camp.

W. MERRITT,

Brevet Major-General, Commanding.

Major WILLIAM RUSSELL, Jr.,

Asst. Adjt. General Hdqrs. Cavalry, Middle Military Division.

No. 2. Report of Lieutenant Colonel Casper Crowninshield, Second Massachusetts Cavalry, commanding Reserve Brigade.

Report of operations of the Cavalry Reserve Brigade during the expedition in Loudoun County, Va.:

Pursuant to instructions received from the brevet major-general commanding the Cavalry Corps to move my brigade to Snickersville and communicate with Brevet Major-General Merritt, I broke camp at Stephenson's Depot on the 29th of November at 3 a. m. and marched to Snickersville. Leaving the Sixth U. S. Cavalry and thirty men of the Second Massachusetts Cavalry to hold the gap, I marched to Bloomfield, expecting to meet Brevet Major-General Merritt near that point. At Bloomfield my advanced guard was fired upon by some of Mosby's men, and two of the First U. S. Cavalry were slightly wounded. Here I learned that our cavalry had moved toward Union. I followed on to Union, thence to Philomont, and finally joined Brevet Major-General Merritt at Snickersville, where the brigade encamped that night, picketing the gap, the mountain road, the Bloomfield road, and to the left as far as the Snickersville and Aldie pike. 30th, the Second Massachusetts and Second U. S. Cavalry were sent through Wood Grive and Hillsborough to Cave Head, on the Potomac, and thence along the river road to Lovettsville, destroying all grain, forage, mills, distilleries, &c., and driving in all stock in that part of the country; at Lovettsville they joined Brevet Brigadier-General Devin's brigade. The Sixth U. S. Cavalry was sent up on the west side of the Blue Ridge, between the ridge and the river, going as far as Rockford, and returning at