51. The enciphering whereby, through the use of the Enigma, the
Procedure Indicator Group becomes the Message Cipher, is to be
carefully distinguished from the enciphering whereby, through the
indicator group procedure (paragraph 45) the Procedure Indicator
Group becomes a Radio Indicator Group. These two processes are
to be kept apart in operation.
56. Before beginning any job of ciphering, be sure that all the
settings on the Enigma are valid and correct.
57. By turning the setting wheels (Einstellraeder), the Message
Cipher obtained as per paragraph 47 is set in on the windows of
58. In enciphering, the keys labelled with the letters of the
"Book Groups" to be ciphered, are pushed all the way down, one
after the other, and the letters which light up are written down
under "Radio Groups".
59. In deciphering, the "Radio Groups" are in similar fashion
turned into "Book Groups".
60. If a wrong key was pressed down by mistake, then the right
cipher wheel (Schluesselwalze) is to be turned back several steps
and the ciphering of as many letters -- including the wrongly
pressed one --- is to be repeated as the number of steps the wheel
was turned back.
In this process, care is to be taken to make sure -- by
comparison with the last correctly ciphered letters, that the
wheels again have their correct positions.
If necessary, not only the right wheel, but also the middle
one and in some cases even the left one are to be turned back as
many steps as they had advanced during the preceding ciphering
motions now to be repeated.
61. If it is not possible, by comparison with the correctly
ciphered group to restore the correct setting, then go back to
the beginning setting (Message Cipher) and repeat the entire
ciphering. The time of this operation can, however be shortened
for the distance up to the last unmistakably correctly ciphered
group by counting the number of letters up to this point and by
then pressing any key that number of times. After reaching this
point, the ciphering is then continued.
Treatment of Cipher Mistakes.
62. In correcting cipher mistakes, follow NV-2 and the Instructions