68 LIVES OF THE PRESIDENTS with directions to proceed on a special mission to Mexico. Grant refused, saying that this was not a military service but a diplomatic mission, and that he claimed the right possessed by every citizen to decline a civil appointment. An effort was after ward made to send him west, to prevent his presence in Washington, but it was soon abandoned. The 39th congress, fearing the result of this action on the part of the president, attached a clause to the army appropriation bill, passed on March 4, 1867, providing that "all orders and instructions relating to military operations shall be issued through the general of the army," and added that he should "not be removed, suspended, or relieved from com mand, or assigned to duty elsewhere than at the headquarters in Washington, except at his own re quest, without the previous approval of the senate." The president signed the bill, with a protest against this clause, and soon obtained an opinion from his attorney-general that it was unconstitutional. The president then undertook to send this opinion to the district commanders, but, finding the secretary of war in opposition, he issued it through the adjutant- general s office. Gen. Sheridan, then at New Orleans, in com mand of the fifth military district, inquired what to do, and Grant replied that a "legal opinion was not entitled to the force of an order," and "to en force his own construction of the law until other-
