Second Corps halting in woods north of Brandy Station in order to conceal their force from the enemy, was necessitated to close communication with Second Corps. The enemy occupied Mount Pony, situated some 3 miles southeast of Culpeper, as a point of observation; also as a point of signal communication with their forces along the Rapidan.

It being obvious that the infantry support halted in woods at Brandy Station could not move without being discovered by the enemy from Mount Pony, and it being very important that we should occupy that point in order to have communication with infantry support, and with general headquarters Army of the Potomac, the necessity was made known to the major-general commanding cavalry, who immediately dispatched a brigade of his command under the guidance of Lieutenant George J. Clarke, signal officer, with orders to take the mountain. They at once moved to the left, while main body engaged enemy in front, and succeeded in gaining the position, Lieutenant Clarke immediately opening communication with headquarters, Second Corps, Lieutenant W. S. Stryker, of the party, soon after joined Lieutenant Clarke, remaining on that important station with hi.

On the 14th the cavalry advanced, driving the enemy to and across the Rapidan.

During the day, assisted by Lieutenant Jerome, who during the advance of the cavalry had gone good service, made frequent telescopic reconnaissances, reporting information derived from same to major-general commanding cavalry.

At 4 p.m. opened communication from Cavalry Corps headquarters at Wharton's house, near the Rapidan, with station on Mount Pony, that station having communication with Second Corps, headquarters Army of the Potomac.

Received and transmitted this date six messages.

September 15, at 1.30 p.m., opened communication with Captain Dinsmore, signal officer with General Gregg, commanding Second Division cavalry, his headquarters being at that time on Garnett's Mountain. Received from that station important reports of observation, also reports and communications from major-general commanding cavalry. Received and transmitted during the day fifteen messages, four of fifty woods. Remained on station at Wharton's house until September 17, keeping communication open from general headquarters Army of the Potomac with Cavalry Corps.

The object of reconnaissance being accomplished, was ordered by chief of staff Cavalry Corps to report to headquarters Army of the Potomac at Culpeper Court-House.

September 19, was ordered by chief signal officer to occupy as a post of observation and communication a point on Cedar Mountain. Opened communication with headquarters Second Corps at Mitchell's Station at 3.30 p.m. same day. From my position had a view of enemy's position along the Rapidan from Barnett's to Morton's Ford.

The town of James City, Madison Court-House, and Rapidan Station also in view, as were the roads leading to and from these points.

Clark's Mountain, on south side of Rapidan, was occupied by the enemy's signal officers, one station communicating with Generals R. E. Lee's and Ewell's headquarters, one with Generals Hill and Early, one with General Fitz. Lee, and one with General J. E. B. Stuart's.