
A letter mailed on October 7th 1969 signed by a "good citizen" was addressed to Sergeant John Lynch, giving him some advice. It read "On occasion, while thinking of the code letters, the pencil wrote: Go to 56 Beach Street. I get the name Jerry, perhaps he knows people or his name is XXXXXXX". It is fairly evident that "code letters" was a reference to the three cryptograms mailed to the Vallejo Times-Herald, San Francisco Chronicle and San Francisco Examiner, postmarked July 31st 1969 - and the author of this letter was giving Sergeant John Lynch a name, who could maybe assist him by way of his knowledge of other people in codebreaking. In other words, it is possible that "Jerry" could assist Sergeant John Lynch because of his connection to law enforcement or Navy cryptography (or was holding a more advantageous position in attempting to solve the final 18 characters). If the "Jerry" mentioned in the correspondence was a real person, it could be argued that the sender believed "Jerry" could be of benefit to Sergeant John Lynch with the remaining unsolved portion of the 408 cipher. Therefore, I needed to find somebody called "Jerry", possibly with links to the Navy (and cryptography), who had a surname of seven letters, thereby explaining the XXXXXXX placed at the end of this correspondence. How Beach Street factors into the equation, I cannot ascertain. Unless Jerry is somehow linked to that address through a friend or acquaintance.

It was later claimed that Lafferty's suspect, William Grant, once sought help from Dr. Edward C. Adams, a psychiatrist living in Orinda, California, and the potential recipient of a Zodiac Killer communication on October 17th 1970 with the pasted newspaper text of "Mon Oct 12, 1970. Edward Adams. The Zodiac is going to change the way of committing murders. I shall announce when I shall commit my murders, The Adamses are Next. you taught me to mean it. ADAMS YOU ARE NEXT. Zodiac".
It is important to identify "Jerry" because the author of the October 7th 1969 communication was almost certainly the author of the "concerned citizen" card mailed on August 10th 1969, two months earlier. Both communications had a similar signature of "good citizen" and "concerned citizen", both were addressed to Sergeant John Lynch of the Vallejo Police Department, both referenced the 408 cipher (by way of "code letters" and the sending of a cipher key), and both used the word "name" in the correspondence twice. This is despite neither being published in the newspapers. The mischievous and cryptic nature of the "good citizen" letter may suggest that the "concerned citizen" author - if one and the same - was playing games with investigators all along. Something we know the Zodiac Killer enjoyed doing throughout his letter-writing campaign.
OFFERING A SOLUTION TO 18 ON 10/7/1969