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Implication to Other Zodiac Ciphers

The Z32 lies in the middle of the Zodiac’s series of ciphers.  Did the Zodiac use an evolutionary approach as he created new ciphers?  If so, we might find common techniques used in each of his ciphers. 

The Z32 is not a monolithic cipher.  As demonstrated, the Z32 can be broken into eight distinct components (the first four characters, delimiters, encoded numeric values, the last five characters of the first line, ‘X’, the four characters meaning ‘west’, the Zodiac’s signature and finally the three characters of the post-script).  Not one of the Zodiac’s ciphers is monolithic.  The Z408 can be broken into two and possibly three parts: the first 390 characters, the ‘O’ with a dot in it at the end of the next to last line might be a delimiter and the 17 characters of the last line.

The Z340 might be broken into a series of ciphers separated by dashes.  One thought that I had was that the last 17 or 18 characters of the Z408 are encoded using the same cipher as the preceding 390 characters but then the Zodiac used a second method like a Vigenere’s cipher on the last line.  I’ve tried various likely Vigenere's keys such as ‘Zodiac’ to no avail…. yet.   The Zodiac only took two weeks generate the Z340 after the Harden’s solved the first 390 characters of the Z408.  The Zodiac knew that the last line of the Z408 was not solved.  Perhaps he used the same techniques that he used on the last line of the Z408 to create the Z340.  The simplest way to create the Z340 would have been to use the same exact cipher used on the unsolved last line of the Z408.  Unfortunately, the Zodiac used too many characters unique to the Z340.  This implies that he used a different set of characters on the Z340.  Possibly, the Zodiac created another substitution cipher and used the same secondary technique as used on the last 18 characters of the Z408 to create the Z340.

The first line of the Z32 contains a six character numeric value.  Each of these six characters are either ambidextrous or reversed.  The last 18 characters of the Z408 are also backwards or ambidextrous or backwards (except the ‘U’).  Are there other strings of characters in Zodiac ciphers that are backwards?

The Zodiac used partially to completely filled geometric shapes as delimiters.  Were these geometric shapes an evolution of the five dashes in the Z340? If the Z340’s dashes are delimiters, what would their purpose be? Perhaps to signal a Vigenere’s cipher key switch or something similar?  The Z340 also contains periods.  Could these period characters simply be periods?

If the last line of the Z408 were ever solved would the entire (or perhaps only up to the first dash of) Z340 use the same techniques? If the Z340 were solved, would the Z32 use the same exact technique? If we take the last five characters of the first line to be ‘NORTH’ and the four characters in the second line to be ‘WEST’, can we use those characters to help solve the Z340?

Little progress has been made resolving the Zodiac’s ciphers since the Harden’s solved the first 390 characters of the Z408 fifty years ago.  Context has to be taken into account if the remaining ciphers are to be solved.  Solving the Z32 would provide important clues to solving the other Zodiac ciphers. 

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