General Grant replied that he had regarded the whole matter of the cipher management as merely an exhibition of departmental bureaucracy, and that he had considered himself as capable as the director of the bureau of telegraph matters in Washington to select a proper person to intrust with the cipher, but he was no stickler for forms and was always ready to obey any order or even wish of the Secretary of War, or any of his superiors, no matter how conveyed, if he only knew or thought it came from him. This ended the episode, and in a few hours the new cipher was ready for use.
Copies of our military cipher messages frequently got into the hands of the Confederates by means of tapping the wires, but they never succeeded in deciphering them, although they went to the extent of advertising them in their newspapers for decipherment, and it may be added, to the credit of our corps of military telegraph operators, that no operator ever proved recreant to his trust.
As compared with the simplicity of complexity and celerity of operation of the Government’s military cipher, that of the Confederates was very crude and clumsy. All their methods of secret communication were unraveled by our signal corps and telegraph operators. In addition to their signal system, the Confederates had a cipher for use in telegraphing and one for sending secret information through the mail. The first telegraph cipher message captured by our forces was the following:
Vicksburg, Dec. 26, 1862.
Gen. J. E. Johnston, Jackson.
I prefer oaavyr, it has reference to xhvkjqchffabpzelreqpzwnyk to prevent anuzeyxswstpjw at that point, raeelpsghvelvtzfautl ilasltlhifnaigtsmmlfgcca jd.
J. C. PEMBERTON,
Lt. Gen. Comdg.
After translation it read:
I prefer Canton. It has reference to fortifications at Yazoo City to prevent passage of river at that point. Force landed about three thousand, above mouth of river.
This code was merely a system of transposition or substitution of letters, which was effected by the use of either one of the three following keys, “Manchester Bluff,” “Complete victory,” or “Come retribution,” in connection with a square formed by twenty-six alphabets, the letters of each being written horizontally, one alphabet under the other, the first beginning with “a,” the second with “b,” the third with “c,” and so on, following the regular sequence of the letters. In the foregoing despatch the key “Manchester Bluff” was used, and by placing those letters over the enciphered letters of the message and applying the squared alphabets and beginning with the letters oaavvr, we look for “o” under the letter m in the top alphabet and find it in the alphabet which begins with c, and translate it c. Then we look for “a” under the letter a (the second letter of Manchester), and find that it means a; then we look for “a” under n (the third letter of Manchester) in the top alphabet, and find it in the alphabet which begins with n, and we translate it n, and so on. This system has no special merit except its age. The ancients used it, and it is generally the plan adopted by tyros in cryptography. The tediousness of its process makes it impractical.