SIR--Your report of the 20th instant is received, and I now proceed to give you the desired instruction in relation to the prisoners of war taken by you among the traitors of East Tennessee. First. All such as can be identified in having been engaged in bridge-burning are to be tried summarily by drum-head court-martial, and, if found guilty, executed on the spot by hanging. It would be well to leave their bodies hanging in the vicinity of the burned bridges. Second. All such as have not been so engaged are to be treated as prisoners of war, and sent with an armed guard to Tuscaloosa, Alabama, there to be kept imprisoned at the depot selected by the Government for prisoners of war. Whenever you can discover that arms are concentrated by these traitors, you will send out detachments, search for and seize the arms. In no case is one of the men, known to have been up in arms against the Government to be released on any pledge or oath of allegiance. The time for such measures is past. They are all to be held as prisoners of war, and held in jail to the end of the war. Such as come in voluntarily, take the oath of allegiance and surrender their arms, are alone to be treated with leniency. Your vigilant execution of these orders is earnestly urged by the Government. Your obedient servant, (Signed) J. P. BENJAMIN, Secretary of War. COL. W. B. WOOD, Knoxville, Tenn. P. S.--Judge Patterson Andy Johnson’s son-in-law, (Rem. Corresp.), Col. Pickens and other ring-leaders of the same class, must be sent at once to Tuscaloosa to jail as prisoners of war. The Hon. W. H. Humphreys had been on the Bench of the United States District Court before Tennessee seceded. He had warmly espoused the cause of the Southern Confederacy and was appointed by it to a similar office under its Government. As preliminary to his new duties, he announced from the Bench his determination to punish all treason and rebellion against the authority he represented. Union men were arraigned before him upon various charges. The only crime of a majority of them was love of the Union. For their political purgation, an oath of allegiance was thought to be sufficient, and upon taking it they were summarily released. The compulsory swearing of fealty during the progress of the war had in many instances a demoralizing effect. It made familiar to men the idea of an oath as having in itself no binding force, and therefore tended to increase the lenient regard which was before too prevalent for the crime of perjury. No doubt an oath of allegiance was administered to many men on both sides of the conflict, under compulsion of their wills, who in their hearts considered it null and void. They felt as Hudibras puts it: