RAID ON THE VIRGINIA CENTRAL RAILROAD—RAID ON THE WELDON RAILROAD—EARLY'S MOVEMENT UPON WASHINGTON—MINING THE WORKS BEFORE PETERSBURG—EXPLOSION OF THE MINE BEFORE PETERSBURG—CAMPAIGN IN THE SHENANDOAH VALLEY—CAPTURE OF THE WELDON RAILROAD.SHERIDAN'S ADVANCE—VISIT TO SHERIDAN—SHERIDAN'S VICTORY IN THE SHENANDOAH—SHERIDAN'S RIDE TO WINCHESTER—CLOSE OF THE CAMPAIGN FOR THE WINTER.CHAPTER LVIII.