This morning a force of rebel cavalry entered Hagerstown, Md. They immediately seized twelve hundred barrels of flour, and commenced tearing up the railroad in the vicinity of the depot. The United States Marshal, the sheriff, and other officials left the town as soon as the rebels entered, carrying with them the public records and other valuables in their different offices. Hundreds of private citizens also left the place.
In consequence of the reported approach of the rebel army under General Lee, the greatest excitement existed in Pennsylvania, and especially in the cities of Philadelphia and Harrisburgh. In the latter city, the Governor of the State issued a proclamation, calling for fifty thousand men, “for immediate service to repel the now imminent danger from invasion by the enemies of the country.” He also telegraphed to the Mayor of Philadelphia to send him twenty thousand men. The latter immediately issued an address to the citizens, in which he embodied the Governor's despatch, and called upon all able-bodied men to assemble next morning at the precinct-houses of the election districts, in readiness to obey the summons to immediate service.
The New Hampshire Eleventh regiment left Concord to-day, en route for the seat of war.--A Union meeting was held at Beaufort, N. C., at which an address was made by C. H. Foster, of North-Carolina. The meeting was largely attended, and resolutions of a highly patriotic character were adopted.--A party of rebels made a descent on the National pickets at Ridgeville, Va., and carried off three of them and several of the Union men of the place. Captain Fiery, rallied a small force, and, pursuing the rebels, succeeded in capturing three prisoners and a  number of horses.--Wheeling Intelligencer, September 13.
Maysville, Ky., was occupied by the rebel forces under Brig.-Gen. R. M. Gano, of General E. Kirby Smith's division of the rebel army.-Maysville Eagle, September 13.
In compliance with orders from the Secretary of War, Gen. Schofield ordered the Provost-Marshal-General for the district of Missouri to proceed without delay to carry into effect the confiscation act, so far as the provisions of said act were subject to be carried into effect by the military authorities of the United States in the district. The property liable to confiscation in the district was estimated at fifty millions.
Westminster, Md., was taken possession of by five hundred rebel cavalry, under the command of Col. Resser. They came dashing into the town at a rapid rate, and immediately proceeded to place pickets around the town, to prevent the citizens from leaving. A gentleman named Crothers, in endeavoring to make his escape, was fired upon and killed. The rebels seized the post-office and the depot; ascertaining that there was a locomotive and two passenger and four freight-cars a short distance from the town, they also despatched a force and brought them in. Upon being established in the town, the rebels proceeded to lay hands upon all the boots, shoes, and clothing that they could find in the stores, for which they tendered in payment confederate money. Secession sympathizers suffered in common with the Union residents, the rebels stating that they had been deceived relative to the secession feeling in Maryland.--Baltimore Clipper, September 13.
New-Market, Md., was occupied by the National forces.
The Union forces stationed at Gauley, Va., under the command of Colonel Lightburn, having been threatened by an overwhelming rebel force in front, flank, and rear, were compelled to evacuate that place, after destroying all the Government stores they were unable to carry away.
To-day the rebel army under Gen. E. Kirby Smith had reached Latonia Springs, Ky., within seven miles of Cincinnati, Ohio, and skirmishing between the rebel and Union pickets commenced on the banks of the West-Licking River, in the vicinity of that city. At night the rebels began to throw up breastworks in front of Fort Wallace. The Union forces in Cincinnati were being largely reenforced from all parts of the State, and also from Gen. Grant's army, several regiments of which having arrived there to day. Considerable excitement existed in the city, although it was considered perfectly safe.
Bloomfield, Mo., was captured by a large body of rebel guerrillas, after a fight of two hours. The town was defended by fifteen hundred State militia, who, being outnumbered, retired.--The Twentieth regiment of Connecticut, commanded by Col. Samuel Ross, left New Haven for Washington.
The Union army under Gen. Buell was on the march to the support of Nashville, Tenn., which was menaced by the rebel army under General Bragg, and eight thousand men from the army of General Rosecrans, under command of General Jefferson C. Davis, arrived there to-day for the purpose of reenforcing General Buell.