..., by a happy chance, an officer and five men bearing a despatch from Dahlgren galloped into their arms. The despatch informed Kilpatrick that Dahlgren would attack on the River Road at sunset, that Kilpatrick must attack at the same time, and together they would ride into Richmond. Colonel Johnson at once drove in Kilpatrick's picket, who, finding himself attacked in rear at once retreated toward the Wh...