The number one guy I’m looking at is Ross Sullivan who worked at RCC Libarary, knew Cheri Jo Bates and went with her to a wedding two weeks prior to her death. During the time of the Zodiac I remember something about cipher books being stolen from all the libraries in the area. Was there at any time, a list made of which books had been stolen? IF Ross got his information from books he read while working at the library then WHAT book(s) was Ross reading from? If you were to find those books you’d be able to recreate the cipher, yes?
i don’t think he went with her to a wedding, i think they may have both been guests at a wedding.
I have heard the rumors that cipher books were stolen or bought up, but that was from all over SF and was most likely just that- rumor. A while ago when I liked Ross as my best subject (currently undecided), I checked what the RCC of ‘today’ had. Being a relatively "new" school, there wasn’t much nor was there likely ever much. Most of the best books are at older institutions, like your Ivies, and usually came from a private collection of a wealthy donor. Many have been scanned into Google or Hathitrust, technology clearly not available. (And many of the best are in French that I have read).
A good question to ask would be what was easily available to him. I would start with Alexander D’Agapeyeff’s and Helen Fouche Gaines’s. Hers can be downloaded somewhere for free, I don’t recall where I found it but think it was on a University website. Both of those books were initially published in 1938.
I think the biggest hint to what book he used would be looking at the simple frequency analysis of letters and how many he chose to have in the 408. He knew E was most common and had the most symbols/letters. But he seems to have chosen more for I then A which is slightly off (usually ETA are considered the top 3), but perhaps he realized he was going to use I a lot. Of course his triangle variations for multiple letters confuse the exact count on some letters.
Interestingly, he used 3 for L, but I have to wonder if he didn’t start out with 2- B and half filled square. As he was going along, he realized that wasn’t enough and filled squares in to add a third.
If you look at the letters and how many choices of substitutions he had, you can get an idea of an approximate order of the frequency count he used. They do vary by source- military, older writings to more current writings, fiction vs. newspapers, etc.- all come up with slight differences in frequency counts, and most books use a different source, so it is possible it could help.
Also, IMHO, it is not a homophonic substitution for the 340 so finding an alternate encipherment method would be useful.
-m
The problem when solved will be simple– Kettering
According to the 408, Z must have used a different frequency table than available today:
ENTAOISLRHDF
In the frequency table chosen, the letter N would be more frequent than the letters T, A, O, I and instead of the letter U, the letter F would appear amongst the 12 most frequent letters.
QT
*ZODIACHRONOLOGY*
I’m not sure the Cipher/Code books he used or that were stolen, I’d like to know as well. but if you read Graysmith’s Zodiac. You can see that many of the symbols are from a Astrology book by OKIN as above so below? I believe the symbols used on the 408 cipher.
