VIRGINIA; The political prospect in America is confused and shifting tn the extreme, but if one may as same that the Presidential content will be go verned, even at the eleventh hour, by the events of the war, it may be concluded with almost equal probability that these events must be looked for principally in Virginia. Recerit information has revealed, with more clearness than formerly, the purpose of General Grant in his late proceedings. After a fort' night of profound inaction, he suddenly massed a heavy force on' his extreme left and threw it across the Weldon Railroad, a few miles sooth of Petersburg There he immediately in trenched himself. No sootier had the Federals seized the position than, as described by an observer on the spot, they "worked like beavers '' to protect themselves agninst attack) and they have since had a month's time to strengthen these defences. But the quietude about Petersburg was soon broken, and some success achieved by the Federals. On Sep tember 29 movements were made on the north side of the James River. Ord's corps advanced that morning, carried the strong fortifications at Chapin's Farm, and captured Id guns and 200 prisoners. Simultaneously General Birney advanced from Deep Bottom, and carried the Newmarket Road and entrenchments. He was marching towards Richmond, and had ar rived at Junction-hill. The Newmarket and Richmond roads and the whole country are full of field fortifications. On the next day, Sept. 30, Warren and Meade moved from their position. on the Weldon Railroad. They at tacked and carried the enemy's lines, and cap tured his position at Poplar-grove. The follow : ng are details of the battles of the 29 h and 30th September, showing that the fighting was of a sanguinary character :—: — On the night of the 28th the 10th Army Corps, under General Birney, and the. 18th Corps under General Ord, crossed the JaraeV River, near Deep Bottom, on ttro muffled pon toon bridges. By daylight on the following day the entire force was aafely across without ap parently having attracted the attention of the enemy. Both Corps advanced rapidly towards Richmond, the 10th Corps following the New market-road, while the 18th advanced on a road nearer the river. 