more important movement, which Ewell learned was to have been an attack on Manassas.
On June 10th, Col. Charles P. Stone began, with the District of Columbia volunteers, what is known as "the Rockville expedition," having for its object the holding of the line of the Potomac from Washington up toward Harper's Ferry, guarding the fords and ferries of that river from Virginia, and any movement on Washington from that direction. This resulted in skirmishes near Seneca mills on the 14th, at Conrad's Ferry on the 17th, at Edward's Ferry on the 18th, at Harper's Ferry July 4th, and at Great Falls July 7th. Colonel Stone was reinforced from time to time with other volunteer troops from Washington. His headquarters were opposite Harper's Ferry July 6th, when he marched, with most of his command, to Williamsport, Md., and thence to Martinsburg, to reinforce Patterson. The Confederate force opposing him was mainly that under Col. Eppa Hunton, in observation at Leesburg.
On June 16th. Col. Maxcy Gregg, with the First South Carolina infantry, about 575 strong, several companies of cavalry and two guns of Kemper's battery, marched from his camp near Fairfax on a reconnoissance to Dranesville, where he learned that several hundred of the enemy had that day come up the Leesburg turnpike to near Hunter's mill. On the morning of the 17th, Gregg rode with a troop of horse to the Potomac, opposite Seneca creek, and reconnoitered. Returning, he marched by Hunter's mill to Vienna, on the Alexandria & Leesburg railroad. About 6 p. m., as he was moving off, the whistle of an approaching train was heard in the direction of Alexandria. He at once marched back, planted his two guns on a hill commanding a curve in the railroad, and placed his infantry and cavalry in support. As the train came round the curve, Kemper opened on it a rapid fire from his guns, which badly damaged the train and caused the Federals, the First Ohio, under Brig.-Gen. R. C. Schenck to escape from it and rapidly retreat. Owing to the lateness of the hour Gregg, could not pursue, but he destroyed one passenger and five platform cars, captured some arms, and killed and wounded several of the enemy, without loss and with credit to his management.
On June 25th a small party of the enemy landed at Mathias Point, under cover of guns from a steamer, and burned the house of Dr. Howe; the object being to discover whether a battery was being located there. On the 27th another descent was made by a force landed from boats. Maj. R. M. Mayo's command of one cavalry and three infantry companies met and drove this body. Brig.-Gen. T. H. Holmes, in command, reported that he then had fifteen companies of volunteers at Mathias Point, and had ordered a section of Walker's battery to the same place.
On July 14th, Colonel Davies, with the Fifteenth New York, made a reconnoissance from Alexandria 7 miles out on the Fairfax road, 10 miles on the Richmond, or Telegraph road, and to Mt. Vernon. Only a small picket was met on the Richmond road. Some of Davies' command visited the house of Col. John A. Washington, near Mt. Vernon, and brought away plantation supplies, taking Colonel Washington's teams and negroes to haul them to camp. Davies sent back the teams and supplies, but kept the negroes to do team duty in his brigade. Col. D. S. Miles, his division commander, instructed Davies to respect private property, and send back the negroes.
