1  2  3  4  5

                   1  U  N  Ij T  E      KW=United States Of
                   2  D  S  A  O  F          America
                   3  M  R  C  B  G
                   4  H  K  L  P  Q      i/j = same cell
                   5  V  W  X  Y  Z      repeats omitted


PT: g o t   a   c i g a r e t t e ?

CT: 35 24 14 23 33   13 35 23 32 15    14 14 15
Russians memorized the proper numbers and "talked"  at about
10-15 words per minute.   One of the advantages was that it afforded
communication by a great variety of media - anything that could be
dotted, knotted, pierced, flashed or indicate numerals in any way
could be used.   The innocuous letter was always suspicious.
Ciphertext letters were indicated by the number of letters written
together; breaks in count by spaces in handwriting; upstrokes,
downstrokes, thumbnail prints, all subtly used to bootleg secrets in
and out of prisons.  The system was universal in penal institutions.
American POW's used it in Vietnam. 

Transposition of the KW provided a further mixed alphabet:

                     B L A C K S M I T H
                     D E F G N O P Q R U
                     V W X Y Z
taken off by columns:

 B D V L E W A F X C G Y K N Z S O M P I Q T R H U


 the Polybius square would be:


                      1  2  3  4  5

                   1  B  D  V  L  E
                   2  W  A  F  X  C
                   3  G  Y  K  N  Z
                   4  S  O  M  P  I
                   5  Q  T  R  H  U



The Nihilists, so named for their opposition to the czarist regime,
added a repeating numerical KW .  Making the cipher a periodic similar
to the Vigenere but with additional weaknesses.


Let KW = ARISE     22 53 45 41 15


PT:   bomb winter palace

NT:   11 42 43 11 21 45 34 52 15 53 44 22 14 22 25 15

Key:  22 53 45 41 15 22 53 45 41 15 22 53 45 41 15 22

CT:   33 97 88 52 36   67 87 97 56 68   66 75 59 63 40   37

or with bifurcation:

      33978  85236  67879  75668  66755  96340  37774

                                             nulls=774


NIHILIST TRANSPOSITION

A simpler form of the Nihilist was in double transposition.  The PT
was written in by rows (or diagonals); a KW switched the rows; a same
or different KW switched the columns, and the resulting CT was removed
by columns or by one of 40 or more routes out of the square.

ex:    KW = SCOTIA   or  524631

PT:  let us hear from you at once concerning jewels xxxx



           Transpose by Columns

             S  C  O  T  I  A
             5  2  4  6  3  1

         1   S  E  U  H  T  L  (let us h)
         2   R  A  F  O  R  E
         3   A  Y  U  T  O  M
         4   A  N  E  B  C  O
         5   E  U  J  W  T  O
         6   X  L  X  X  S  E


    Transpose by Rows


              1  2  3  4  5  6

       S 5    E  U  J  W  T  O
       C 2    R  A  F  O  R  E
       O 4    A  N  E  B  C  O
       T 6    X  L  X  X  S  E
       I 3    A  Y  U  T  O  M
       A 1    S  E  U  H  T  L


   X= bad choice for nulls


The resulting cryptogram is:



E U J W T   O R A F O  R E A N E   B C O X L   X X S E A

Y U T O M   S E U H T    L.


(message length and 5th group are entries to solution)



Clues to cryptanalysis of the Nihilist systems were reconstructing the
routes, evenness of distribution of vowels, period determination and
digram/trigram frequency in CT.  The USA Army for many years used a
similar system.  

RUSSIAN LANGUAGE NOTE

Every language has a frequency distribution. 

A prime difficulty for English speaking students of Russian is the
scarcity of linguistic cognates in the two languages.  Russian is more
complex than other romantic languages which have many common word
derivatives.  The highly inflected Russian grammar aids rather than
hinders the cryptographer by supplying him with valuable tools for
decrypting.