Last night a train of about eighty wagons was sent out from New Creek, heavily laden with commissary stores for the garrison at Petersburgh, West-Virginia, and accompanying the train was an escort of about eight hundred men, being detachments from the Twenty-third Illinois, (Irish brigade,) Fourth Virginia cavalry, Second Maryland, First and Fourteenth Virginia infantry, and one hundred of the Ringgold Cavalry battalion, the whole under command of Colonel J. W. Snyder. Nothing unusual occurred until the train got about three miles south of Williamsport to-day, when it was suddenly set upon at different points by open and concealed forces of the rebels. Although somewhat surprised by the suddenness of the attack, the guard at once formed and deployed for action. Then it was that a hard fight ensued, commencing at three o'clock in the afternoon and lasting for over four hours, at the expiration of which time it was found that the Nationals had lost about eighty in killed and wounded. The enemy's loss was about one hundred. In the early part of the fight the rebels opened fire from four pieces of artillery. The superiority of their strength — there being in all about two thousand men — also gave them the advantage in outflanking movements, and they exercised their ingenuity simultaneously to operate on the front, rear, and flanks of Colonel Snyder's command. They, however, completely failed of their object, which seemed to be to try to surround, and, if possible, capture the whole party. Several times the rebel lines were broken, and several times the rebel charges were repulsed. At last, as night closed, the superior numbers of rebels gained them a success.
Colonel Jourdan, commanding the sub-district of Beaufort, made a dash into Jones and Onslow counties, N. C., for the purpose of surprising and capturing detachments of cavalry near Swansboro and Jacksonville. He returned to Morehead City this day, having been entirely successful, the expedition being a complete surprise to the rebels. He captured about thirty prisoners, (cavalry,) including one lieutenant, a large number of horses, arms, and equipments, and destroyed a large quantity of ammunition and other property. His command consisted of detachments of the One Hundred and Fifty-eighth New York, Ninth Vermont, Twelfth and Mix's cavalry — in all, about three hundred men. They marched one hundred miles in about fifty hours, meeting with no loss whatever.
The Twenty-first Missouri regiment, in command of Major Moore, left Memphis yesterday, on board the steamer Sir William Wallace, and to-day, while passing the foot of Islands Nos. 70 and 71, the boat was fired upon from the Mississippi shore by a large party of guerrillas, who were lying in ambush at a place where boats had to run close to shore. There were from fifty to one hundred shots fired in the space of about ten minutes, resulting in killing one man and wounding six others.
Last night Colonel Thoburn, in command of the National garrison at Petersburgh, West-Virginia, evacuated that post in consequence of receiving  information that the enemy in large force would attack him in the morning. The enemy did attack Petersburgh this morning with artillery. They made regular approaches, and finally charged, but found no opposing force. Colonel Thoburn was within hearing with his retreating column.
A party of seven men belonging to the steamer Southwester were sent ashore at Bolivar Landing, Tenn., on a foraging expedition, taking with them nine mules and horses and wagons. They had scarcely got out of sight when they were set upon and surrounded by nine guerrillas, who leaped from the bushes with shouts to surrender. This they did. The animals were cut from the wagons, and the prisoners ordered to mount, when they were taken to the interior.