Cincinnati, May 18. Gen. Burnside issued a general order to-day announciog tho finding of the court-martial m the caso of Vallandig ham. The court find him guilty of charges and speoifieations as already pub lished, and sentenee him to be elosely confined in sorae fortres3 of tho Unitec States during the war. . Gen. Burnside approves the sentence, and has nan,ed Fort Warren, near Boston Harbor, as the place of his imprison ment. He will be conveyed to Fort Warren to-morrow under a strong guard.