There may be a slim chance that the Zodiac Killer was hinting at the murder of Cheri Jo Bates as early as November 10th 1969, rather than fourteen months later on March 13th 1971 when he claimed "riverside activity" in a letter mailed to the Los Angeles Times newspaper. If true, this would have been three weeks after Chief Kinkead of the Riverside Police Department contacted Earl Randol, Sheriff of Napa County, exploring a link between the Cheri Jo Bates and Zodiac case on October 20th 1969.

Lately I have been examining the Edward C. Adams postcard mailed from Berkeley on October 17th 1970, which stated by use of newspaper cuttings "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".

However, this wasn't the first communication to issue a direct threat toward an individual using cuttings and similar verbiage, when somebody claiming to be the Zodiac Killer mailed "Mr. (redacted) "your next" The Zodiac" in a letter postmarked Montclair, California on November 10th 1969, which is situated approximately 19 miles (by crow) from the murder site of Cheri Jo Bates. The cuttings were attached using scotch tape onto school notebook paper, such as that carried by Cheri Jo Bates when she visited the Riverside City College library on October 30th 1966 and was spotted by a Mexican-American student shortly before 6:00pm. Writing paper similar to that used in the "Bates Had to Die" letters on April 30th 1967, which suggested "There Will Be More" victims. We have the Riverside Desktop Poem also finishing with the parting message of "just wait till next time". The Montclair and Berkeley communications both signed off with the "Zodiac" pseudonym, as did the "13-Hole" postcard on October 6th 1970.     

On July 26th 1970 in his "Little List" letter, the Zodiac Killer used wording similar to that in the "Confession" letter mailed on November 29th 1966, which was partially reproduced by the Inside Detective magazine in January 1969, featuring the murder of Cheri Jo Bates. The Confession letter read "She squirmed and shook as I chocked her, and her lips twiched. She let out a scream once and I kicked her in the head to shut her up". The Little List letter read "Some I shall tie over ant hills and watch them scream + twich and sqwirm". The Inside Detective magazine not only mentioned the "school notebook" of Cheri Jo Bates on page 5 (shown above), but the article was entitled "YOUR DAUGHTER MAY BE NEXT" by John Montgomery, loosely taken from "I lay awake nights thinking about my next victom" and "Keep your sisters, daughters and wives off the streets and alleys". 

​Did the Zodiac Killer take "YOUR" and "NEXT" directly (or indirectly) from the Inside Detective magazine in similar fashion to the "Little List" letter, which may have borrowed from this magazine also? If the threat of "your next" was using lowercase cuttings as the FBI file appears to suggest, then this would somewhat diminish the connection between the Montclair letter and magazine.  

​The FBI file made the distinction that these were magazine cuttings rather than newspaper cuttings, so if the Zodiac Killer really was the murderer of Cheri Jo Bates, then he had every reason to have focused on this magazine more than once. The connection suggested here could be construed as extremely fragile, but for the fact that this letter was mailed relatively close to Riverside (and unpublished), and offered an extremely similar threat via affixed cuttings, to that given to Edward Adams a year later. What would make this a more interesting proposition, is if the person threatened in Clarinda, Iowa could be identified by a FOIA request, and the subsequrnt male individual turned out to have some previous connection to Riverside and/or the murder investigation of Cheri Jo Bates. If this was shown to be the case, then there is a high probability that the Zodiac Killer was linking himself to Riverside far earlier than previously thought.    

UPDATE SEPT 21ST 2025: At the bottom of the Montclair FBI file the name Allen L. Donielson is mentioned. If this is not the recipient of the "Zodiac Killer" threatening letter, then there is a high probability he is somehow connected to the person that did receive it. Allen L. Donielson became the United States Attorney for the Southern District of Iowa in 1969. On November 1st 1976, the Governor of Iowa appointed him as the first judge of the newly created Iowa Court of Appeals. These and other United States Attorneys for the district have been responsible for the prosecution of some very important cases in the state. So this man was connected to Iowa where the threat was aimed. Two weeks before this threat (estimated: October 27th 1969) a similar letter bearing the same message had been mailed (from where to where is unknown).These two threats, likely towards an attorney (or more than one), began five days after the Zodiac Killer requested that either Melvin Belli or Francis Lee Bailey, two prominent and well-known attorneys, join him in a discussion on the Jim Dunbar Show on October 22nd 1969. The Zodiac Killer's appearance on the show was likely thwarted by the imposter, Eric Weill. But why (if the Zodiac Killer) would he switch his attention from San Francisco to Clarinda in Iowa within 19 days (or possibly 5 days)? I have added a newspaper article from December 23rd 1969 at the foot of this page, regarding the conclusion to a case of four draft dodgers. This was the nearest thing I could find of any relevance to Allen L. Donielson in this time period

Recently it has been shown that the Zodiac Killer fashioned the October 6th 1970 "13-Hole" and October 17th 1970 "Edward Adams" postcards by using significant parts of the "Letters to the Editor" page from the San Francisco Chronicle in each instance. The question has always been, did the Zodiac Killer know (or come across) Edward C. Adams, his wife, or any of their family members? After all, the October 17th 1970 postcard was mailed directly to Edward C. Adams at 102 Camino Don Miguel, Orinda, California, and postmarked Berkeley, just a few miles west of his home. The threat of "ADAMS YOU ARE NEXT" could be interpreted that Edward C. Adams, having recently experienced a death in the family, was next for the afterlife.

This was the route explored by excellent Zodiac researcher Mike Morford when he found and posted a newspaper article on the Zodiac Tapatalk forum earlier this year, announcing the death of Florence Wolcott on October 14th 1970, the mother-in-law of Edward C. Adams, who died three days before the "You Are Next" postcard was postmarked. Mike Morford stated that the postcard was created on October 12th 1970, but that isn't necessarily the truth, because the postcard was only fashioned from San Francisco Chronicle newspaper cuttings from that date and very probably mailed four or five days later. The Zodiac Killer could have taken cuttings from the October 12th 1970 San Francisco Chronicle newspaper at any time between October 12th and October 17th.

​Every newspaper cutting, apart from the large capitalized "YOU", can be found in the October 12th 1970 newspaper (the search function easily finds black text but not white). However, despite trawling through every page manually, I have yet been unable to locate the "YOU" on this specific date. Either I have missed it, or it may be present in the San Francisco Chronicle pages between the dates of October 12th and 17th, or another publication. If the "YOU" (on a dark background) can be found in the San Francisco Chronicle newspaper after the death of Florence Wolcott and before the time the Edward Adams postcard was mailed, it could bolster the case for this communication being a response to her death. Mike Morford speculated on whether someone knew that Edward C. Adams' mother-in-law was on "her last legs" and imminent for death, responding in this callous manner on October 17th 1970. The timing of her death just three days before the mailing date, the threat of "You Are Next", and the knowledge of Edward C. Adams' home address could suggest some familiarity with this family.

The newspaper article shown above is from the Orland Unit Register from October 15th 1970, so what is the likelihood that the Zodiac Killer came across this article? Orland is a city 110 miles northeast of Vallejo (by crow) which had a population of 2,310 in 1970, so if he was knowledgeable about the death of Florence Wolcott, isn't it more likely he got the news direct from the family, or somebody close to them?

THE EDWARD ADAMS POSTCARD WAS MAILED BY ZODIAC

If you believe that the "13-Hole" postcard was mailed by the Zodiac Killer on October 6th 1970 (which I do), it is with absolute certainty that he mailed the Edward Adams communication on October 17th 1970 from Berkeley, California. The postcard, affixed with newspaper cuttings, read "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".

The section in blue was taken from the breaking news story about the Zodiac Killer on page 5 of the October 12th 1970 San Francisco Chronicle  The newspaper was reporting on the "13-Hole" postcard and the previously withheld "Little List​" letter mailed on July 26th 1970. The 8 words in red were all taken from a column on page 38 entitled "Question Man By O' Hara", just to the right side of the "Letters to the Editor" section. When I typed in a search for the word "taught" in the San Francisco Chronicle on October 12th 1970, it appeared only on page 38 in the "Question Man" column (shown below), followed by the other 7 words in the same column, which Zodiac used to spread haphazardly over his Edward Adams postcard. The 8 words can all be found in these two small responses to the "Question Man" below. The uppercase "M" in "Mean" can be found on the same page in the name "Abe Mellinkoff" just to the left of these responses.

​In the upside-down text of the "13-Hole" postcard, the Zodiac Killer created 17 words from the September 23rd 1970 San Francisco Chronicle "Morning Report" by Abe Mellinkoff, and one word from the column "Question Man By O' Hara". In other words, the Zodiac Killer created a total of 18 words he sourced from the "Letters to the Editor" page on September 23rd 1970, which he used on his "13-Hole" postcard, and created 8 words and the letter "M" from this very same page on October 12th 1970, which he used on his Edward Adams postcard. Therefore, Abe Mellinkoff and "Question Man By O' Hara" featured in both postcards. That's because they were designed by the same person.     

The Zodiac Killer often referred to the "Editor" in his communications, including the "13-Hole" postcard, so it isn't surprising that a large quantity of newspaper cuttings were sourced from the "Letters to the Editor" page from the San Francisco Chronicle newspaper on September 23rd 1970 and October 12th 1970. Here is the upside-down text from the "13-Hole" postcard, which read "There are reports city police pig cops are closeing in on me. Fk I'm crackproof. What is the price tag now". Everything in red can be sourced from this single article by Abe Mellinkoff on page 54 of the San Francisco Chronicle on September 23rd 1970 (shown below)..See the recent article More on the "Pace" Postcard Cuttings for a more detailed explanation.

Below are the two pages from the San Francisco Chronicle on September 23rd 1970 and October 12th 1970, that the Zodiac Killer mined heavily for his newspaper cuttings to paste onto his "13-Hole" and Edward Adams postcards. This proves without a shadow of doubt that the Zodiac Killer was responsible for both communications.  

It was easy for the Zodiac Killer to find the "Adam" (and his signature "Zodiac") he used in "Adamses" because it was present on the front page of the October 12th 1970 San Francisco Chronicle next to his own story. The "ses" was located by searching for "passes" in the multiple sports pages covering American football. The surname "Adams" was also easily found in the sports pages. The forename of "Edward" was present in a story about Edward M. Kennedy on page 8. Bearing in mind that the Zodiac Killer showed an interest in Gilbert & Sullivan's "The Mikado" and films, it would probably have been apt had he chosen the word "Next" from page 43 featuring a Gilbert & Sullivan opera by the The Lamplighters and the cinema section. It was located in the listings of Bay Area Movies in the advertisement for the Albany Cinema at 1115 Solano Avenue in Berkeley, the very location that the Edward Adams postcard was mailed from. However, because of the "N" font, it appears that "Next" was sourced from the sports pages yet again.

​The surname "ADAMS" in uppercase letters can be found on page 30, in addition to "ARE" in two car advertisements (shown below). The large "YOU" with a dark background may be from another publication, because in some images of the Edward Adams postcard it appears a different style background (see the attached image on the right to see this difference).    
​EXTRA READING: THE "PACE" POSTCARD AUTHENTIC 
FOLLOW UP ARTICLE: THE SEARCH FOR "YOU" IN PRINT 

The newspaper coverage regarding the disappearance of Donna Lass began on September 22nd 1970 and continued with a flurry of articles until the end of the month. This was the period of time the Zodiac Killer was constructing his "13-Hole" postcard taking cuttings from the San Francisco Chronicle (September 23rd 1970), San Francisco Examiner (September 25th 1970) and Oakland Tribune (September 25th 1970). We know that the Zodiac responded to recent newspaper coverage about himself and random stories, so was he manufacturing and designing the "13-Hole" postcard in reponse to the unfolding story of Donna Lass.

​It had been documented that somebody claiming to be the Zodiac Killer had already contacted Incline Village (and other areas nearby), threatening to target school buses in late November and the first half of December.of 1969, which predated by over a year the Zodiac Boise Cascade advertisement at Incline Village, that he used in his "Pines" postcard on March 22nd 1971. If the threats to the Lake Tahoe region lasting several weeks in 1969 were the Zodiac Killer, then he had every reason to be following the story of a missing woman in Lake Tahoe in 1970, whether he was her murderer.or not. He would also have threatened several "Lake Tahoe areas" in 1969 before telling us to "pass Lake Tahoe areas" on March 22nd 1971. In fact, the Sacramento Bee newspaper article on December 15th 1969 just happens to contain the words "passed", "Lake Tahoe" and "areas" (shown below in blue)..

The "13-Hole" postcard, postmarked October 6th 1970, not only contained a running victim total of 13 to mirror his count on July 26th 1970, but he added a red crucifix directly underneath. The number 13 had a small line extending from the newspaper cutting on its bottom face, as if to indicate that the crucifix may play a role in the victim total. Was the Zodiac Killer expressing that he had currently killed 13 people to date, with one victim yet to be found, which he symbolized by the addition of a grave marker in the form of a crucifix?

​This was the only time the Zodiac Killer added a crucifix to his communications, and the only time he would have been playing into the narrative of a victim still currently alive and missing in the eyes of law enforcement. One can only speculate on its purpose, but if the Zodiac Killer had murdered Donna Lass and buried her in a grave at Yuba Gap in Placer County, the crucifix could signify a burial site. The Zodiac Killer, by not adding Donna Lass to the running total in the conventional manner, could have been the precursor to the game he would ultimately play 5 1/2 months later. A game that possibly came to fruition when he mailed the "Pines" postcard on March 22nd 1971 and added a fourteenth punch-hole in sinister fashion. 

A red crucifix most often represents the blood of Christ and the sacrifice of his crucifixion. In this instance, the Zodiac Killer may have been using this color to depict the murder of Donna Lass and a burial marker to his fourteenth victim, that he would cryptically suggest on October 27th 1970, and further elaborate upon on March 22nd 1971. However, did the red crucifix have a dual purpose as a red cross, bearing in mind Donna Lass was a nurse. The relationship between the Red Cross and nursing dates back to the influence of Florence Nightingale, who inspired the organization's founding and subsequent work in wartime and disaster nursing. Historically, nurses wore the Red Cross emblem for protection under the Geneva Conventions, though this is now rare outside of armed conflict. The Red Cross has a long-standing and deep connection to nursing in America, dating back to its founder, Clara Barton, a nurse and humanitarian. The American Red Cross relies heavily on the expertise of nurses and other health professionals as volunteers and staff to support disaster relief, community health initiatives, and blood drives. 

Irrespective of these speculative offerings, we definitely have a "Zodiac" threat on school buses around Lake Tahoe in 1969, a "13-Hole" postcard being designed by the Zodiac Killer the day after the disappearance of Donna Lass from Lake Tahoe was reported in the newspapers, and a "Pines" postcard stating "pass Lake Tahoe areas" with a further punch-hole. If the Zodiac Killer had sourced all his cuttings from the newspapers for the "13-Hole" postcard by September 25th 1970, why did he wait over a week into October to mail this communication? Was he waiting for the news stories of Donna Lass to fade away, to see if anything needed to be added to the postcard?

The prolonged threats toward school buses and schools in Lake Tahoe over several weeks in November and December 1969 mirrored the "Zodiac" threats toward school teacher Daniel Williams, which lasted from October 23rd 1969 to November 5th 1969. If they were hoaxers, they were certainly persistent ones.   

MORE ON THE "PACE" POSTCARD CUTTINGS ​

A while ago I wrote an article on the newspaper sources used in the construction of the October 6th 1970 "13-Hole" postcard, unearthed by many different contributors. Jarrett Kobek, author of "Motor Spirit" and "How to find Zodiac", identified the September 23rd 1970 San Francisco Chronicle article that contained the upside-down text of "THERE ARE REPORTS".. So I did a little extra digging and found that the overwhelming majority of the upside-down text can be found in this article (shown below).  The upside-down text read "There are reports city police pig cops are closeing in on me. Fk I'm crackproof. What is the price tag now". Everything in red can be sourced from this single article on page 54 of the San Francisco Chronicle. The word "I'm" can be found next to this article on page 54. On page 53 we can find "What is" (with the uppercase W). And on page 29 we can find "the price", "The price" and "double in price" (in darker print). However, these two words were not cut out together, so it's clear that the Zodiac Killer, knowing the message he wanted to send, originally sourced (and possibly pasted) the word "the" from the article below, before flicking back through the pages to the "Business Section" he had already read in order to find the word "price". This would have been the likeliest page to find this word. It can be found on page 53 along with "What is", so this is an option too. Everything in the upside-down Zodiac text was therefore sourced from three pages of the San Francisco Chronicle newspaper (pages 29, 53, 54). It must be noted that the word "pig", "closeing", "crackproof" and "tag" were all created using two cuttings (or more). 

The rest of the newspapers identified for the remainder of the text on the "13-Hole" postcard were found by Vasa Croe, Brubaker, Cragle and Jibberjabber. If I've missed anybody, please let me know. In total, three newspapers were identified: The San Francisco Chronicle on September 23rd 1970, The San Francisco Examiner on September 25th 1970 and the Oakland Tribune on September 25th 1970. These cuttings were sourced from newspapers published just one and three days after the news broke about the disappearance of Donna Lass from the Sahara Tahoe Hotel & Casino at Lake Tahoe. Donna Lass went missing on September 6th 1970, the newspapers first reported her disappearance on September 22nd 1970, and the upside-down text was sourced from the San Francisco Chronicle on September 23rd 1970. So was the "13-Hole" postcard a response to the abduction of Donna Lass?

​In an earlier article I examined the upside-down text "around in the snow" on the "Pines" postcard, believing that it may have signified the area where the body of Donna Lass could be found - and if we righted this text through 180 degrees by turning the postcard around, the "Sierra Club" pasting (Clair Tappaan Lodge) and the punch-hole would likely identify the location of Donna Lass' burial site. I believe it did to incredible accuracy. The upside-down text for the "13-Hole" postcard was sourced from the San Francisco Chronicle on September 23rd 1970, which was the day after her disappearance from the Sahara Tahoe Hotel & Casino was first reported in the newspapers. So was this text sourced with the express purpose of highlighting something about Donna Lass? The "13-Hole" postcard and "Pines" postcard both had inverted text and punch-holes.

Were the 13 punch-holes on the "13-Hole" postcard signifying the burial sites of his 13 victims? The Zodiac Killer victim total hadn't increased from July 26th 1970 to the time the "13-Hole" postcard arrived at the San Francisco Chronicle, so why didn't the Zodiac Killer increase his victim count in October to include Donna Lass from September 6th 1970, if he was her murderer? Was it because she was only currently recognised as a disappearance and the Zodiac Killer wanted to play games with law enforcement, which he would ultimately achieve when he mailed the "Pines" postcard on March 22nd 1971? Or was he writing "13" on the postcard as confirmation, because his July 26th 1970 letter claiming the same number of victims, was not currently published in the newspapers.   

But what was the article about on page 29 of the San Francisco Chronicle on September 23rd 1970, the day after Donna's disappearance was first reported in the newspapers, that the Zodiac Killer may have sourced to use the word "price" for his upside-down text on the "13-Hole" postcard? The Zodiac Killer had three choices on the same page. One was about the Sanoma mines, one was about stock prices, and the other was about the Boise Cascade Corporation, the very company whose advertisement he had used on the "Pines" postcard on March 22nd 1971. Therefore, a fighting possibility exists that the Zodiac Killer used a cutting about the Boise Cascade Corporation for both postcards, indelibly linking them together.  

As pointed out earlier, the Zodiac Killer also took cuttings from the Oakland Tribune on September 25th 1970, three days after Donna Lass was reported missing. If the Zodiac Killer had buried Donna Lass west of Clair Tappaan Lodge and the Boise Cascade Corporation developments at Incline Village, did he select the word "price" from the above page of the Chronicle newspaper article, knowing that he would later mail a cryptic postcard mentioning the "Lake Tahoe areas" and provide us with a further cutting from the Boise Cascade Corporation, but this time with directions to her remains? Even if the word "price" was not sourced directly from the Boise Cascade article above, and he instead opted to cut the word "price" from the darker "double in price" text on page 29, he would still have used two San Francisco Chronicle newspaper pages containing Boise Cascade articles to fashion both postcards. When the San Francisco Chronicle published this advertisement about Boise Cascade at Incline Village on March 19th 1971, did the Zodiac Killer seize his opportunity and decide to reveal the burial site of Donna Lass?. The Oakland Tribune on September 20th 1970 also ran an article about the Boise Cascade Corporation (see below). However, they mentioned "Incline Village", five days before the Zodiac Killer may have taken "price" from a Boise Cascade newspaper article, six months before he mailed a postcard on March 22nd 1971, using a Boise Cascade advertisement depicting Incline Village. .     

There may have been a change in the Zodiac Killer's approach to encrypting his ciphers/codes after the 408 and 340 cryptograms, in that the Z13 and Z32 were specifically designed with maybe just six characters forming the bedrock of each solution, but with a key of just three characters. The key characters in the April 20th 1970 letter were the three 8's, whereas the key characters in the "Button" letter Z32 code on June 26th 1970 were the three repeating symbols of C, O and the triangle. These three symbols (characters) were seemingly the key to unlocking both codes mailed on April 20th 1970 and June 26th 1970, with the remaining characters beyond the total of six possibly meaningless filler placed around them.

Once the Zodiac Killer had supplied us with the prompt of "The Mt. Diablo Code concerns Radians & # inches along the radians" on July 26th 1970, the placement of "four radians and five inches" into the Z32 from position 9 to 32, unlocked the answer of "estimate" from position 1 to 8, to identify the complete solution of "Estimate: four radians and five inches". There was a total of six characters at play here, but only three were key characters involved in the solution. The key characters in the Z13 on April 20th 1970 were the three circled 8's, but a total of six characters may also have been at play here. They were the three 8's, and the "M", "E" and "crosshairs". If the proposed solution of "Me⊕" for the Z13 is correct, then both the Z13 and Z32 codes follow the same template.   

It can be seen above in the Z32 that six characters are at play here, but only the three characters at positions 14, 26 and 32 are key to the solution. The characters at 14, 26 and 32 within "four radians and five inches", unlock the characters at positions 1, 2 and 6 to give us the word "estimate" and complete the full solution. In the Z13 below we again have six characters at play, but only three characters at positions 5, 7 and 9 are key to the solution of "Me⊕".    

This drives at the heart of the question, of whether the Zodiac Killer used redundant characters in 54% of the Z13 and 81% of the Z32 to change the methodology he employed in his previous ciphers. If the proposed solution to the Z13 is correct, then there is a good argument to be had that the Zodiac Killer used only six functional characters in both designs, of which, only three were key to each solution. That key being the three circled 8's in the Z13, and the C, O and △ in the Z32.

Recently I have released two articles examining the solution of "Me⊕" in the April 20th 1970 letter mailed by the Zodiac Killer, having been formulated by a combination of Edgar Allan Poe, the 340 cipher and the three 8's in the Z13 code. Further hints towards this solution have possibly been unearthed in the 13-Hole postcard mailed a few months later in October, and Exorcist letter mailed on January 29th 1974 in which the Zodiac Killer changed his signature to "Me" for the first time.

​The April 20th 1970 letter tempted us with an identity stating "My name is", the 13-Hole postcard contained 13 holes punched into the fabric of its design and the phrase "Fk I'm crackproof", the March 13th 1971 "Los Angeles" continued the theme by proclaiming "This is the Zodiac speaking Like I have allways said, I am crack proof", with the Exorcist letter again suggesting an identity might be hidden in its contents by the introduction of "Yours truley", followed by the Tit-Willow verse from "The Mikado". But crucially, the January 29th 1974 letter added the signature of "Me", that can be replicated using the three 8's from the Z13 code by employing a cipher wheel described by Edgar Allan Poe. But there is one communication nestled in between these other mailings, that also tempted us with a name, much like the April 20th 1970 letter. The Halloween card, mailed on October 27th 1970, began with "I feel it in my bones you ache to know my name. And so I'll clue you in".    

If the Halloween card was going to give us the answer of "Me" proposed in the Z13 code, you would expect to find this word embedded in its design. Not only was the word "Me" curiously obvious in the Halloween card inner, it was present twice. The Zodiac Killer was clearly employing the eye in the knothole of the tree as himself, by surrounding the knothole with the ominous threat of "Peek-a-boo you are doomed".

But there is one striking feature about the writing on the tree. After the phrase "PEEK-A-BOO" the Zodiac Killer positions the word "DOOMED", such that the "ME" lines up with "PEEK-A-BOO" to create "PEEK-A-BOO, ME". It is definitely noticeable that the word "ME" is visibly larger and bolder than the rest of the writing, as if to place emphasis on this pronoun. The skeleton's left arm is also affixed to the Halloween card in such a manner that it separates the word "GAME" to spell "ME". The word "BOO" is written on the card inner at a 45 degree angle so that it too lines up with the word "ME".

The word "BOO" around the knothole and the word "BOO" to the immediate left of the skeleton, are both positioned in alignment with the word "ME". Was the Zodiac Killer giving us the answer of "ME" to "I feel it in my bones you ache to know my name. And so I'll clue you in"? Thereby replicating the answer of "ME" possibly given by the proposed solution to the Z13 code on April 20th 1970. And the signature of "Me" he would ultimately deliver on January 29th 1974 to the San Francisco Chronicle.    FURTHER READING:

The April 20th 1970 letter opens with "This is the Zodiac speaking. By the way have you cracked the last cipher I sent you? My name is....". One of the takeaways from the mention of his previous cipher while beginning this communication, has been that something about that previous cipher may aid in the solving of the current Z13 code. Many have taken the code key from that now solved 340 cipher and tried to apply it to the Z13 code. While some of those attempts have produced interesting outcomes, they have all required some form of manipulation to generate a desired result, which leaves room for objection. But what if the answer or key lay in the unsolved 340 cipher at the time Zodiac mailed his Z13 code on April 20th 1970. Bearing in mind this latest letter was suggesting that the Z13 code would reveal a "name" or "identity", it is quite possible that his identity in the unsolved 340 cipher held the clue.

In the 340 cipher on the final line he appeared to give us his signature of ZODIAC from characters 333 to 338. However, he replaced the "D" with a blackened triangle, reversed the "I" and "A", and changed the "C" for a "K". Despite this, it's unmistakable presence is there for all to see. What if we took this identity to solve the Z13 code.  

As stated previously, Professor Donald C. B. Marsh invoked the name of Edgar Allan Poe to challenge Zodiac to reveal his name on October 22nd 1969, hoping that the Zodiac Killer would utilize the cryptographic works of Poe to create any forthcoming ciphers. Taking one look at Poe's essay, "A Few Words on Secret Writing" in the July edition of Graham's magazine, you can see the scytale method of decryption that can be used to solve Zodiac's 340 cipher, the cryptographic technique of splitting of the alphabet A through M and N through Z, which Zodiac employed in his design of the Z13 code, and the cipher wheel explained by Poe, which not only decodes the "near Zodiac" on the final line of the 340 cipher to give us the key, but provides us with a resulting key that the Zodiac placed directly into his 13 characters on April 20th 1970, that generates an answer he would later reveal as his signature on January 29th 1974. That signature was "Me". 

The "near Zodiac" in the 340 cipher has simply been manipulated using a cipher wheel. When we compare the correct spelling of ZODIAC to the version supplied on the final line of the 340 cipher, we can see that Z to Z, O to O, and D to triangle generates no difference alphabetically (000). Whereas "IAC" to "AIK" generates a shift of 8 positions for each letter, producing 888. This provides us with 000888, the possible origin of the three circled 8's in the Z13 code. Visit the Caesar cipher wheel here and type in the number 8 (see below). The inner wheel will spin 8 positions clockwise so that the outer wheel "I" is represented by the inner wheel "A" (and vice versa). The outer wheel "K" is represented by inner wheel "C" (and vice versa). This is the bedrock of the switch from "IAC" to "AIK" in the spelling of ZODIAC. If we place the 13 characters from the April 20th 1970 letter within a cipher wheel (shown above), forming an inner and outer ring, and then spin the inner wheel clockwise by 8 positions, the three circled 8's land over "ME" and the "crosshairs". The signature he chose to use in the "Exorcist" letter on January 29th 1974, created by a technique described by Poe in "A Few Words on Secret Writing".    

But how do we know that the three circled 8's are the key to solving the Z13 code? In the April 20th 1970 letter the Zodiac Killer wrote "This is the Zodiac speaking. By the way have you cracked the last cipher I sent you? My name is....", followed by 13 characters. The next time the Zodiac used the verb "to crack", is when he told us he was crackproof in the 13-Hole postcard at the beginning of October 1970, five and a half months later. The Zodiac Killer stated "Fk I'm crackproof" and punched 13 holes into the fabric of the postcard. But just like the April 20th 1970 letter featured three circled 8's in a configuration of 13 characters, the postcard in October separated out three punch-holes from the other ten. These three punch-holes were positioned almost directly below the positions the three 8's slotted into the Z13 code (see below). In other words, pull the three 8's downwards from the Z13 code and you get the 10:3 configuration shown in the 13-Hole postcard.  

Was the Zodiac Killer highlighting the three punch-holes (888) from the total of 13 to show that these were the key to solving the "crackproof" Z13 code on April 20th 1970? In total, we have the three circled 8's generated by a cipher wheel from the "near Zodiac" in the 340 cipher, placed into the Z13 code five months later, which by using a cipher wheel once again, generated the signature of "Me" from the Z13 code, that is present as the signature in the Exorcist letter on January 29th 1974. The Edgar Allan Poe essay "A Few Words on Secret Writing", featuring the cipher wheel, the scytale method of cryptography, and the technique of splitting the alphabet into 13 characters, which are all integral to the solving of the 340 cipher and the possible design of the Z13 code, may very well have been chosen because of the challenge by Marsh on October 22nd 1969. He wanted the Zodiac Killer to send a cipher to The American Cryptogram Association that would honestly include his name. The murderer of five may have given Professor Marsh more than he bargained for.

On January 29th 1974, April 24th 1978 and October 27th 1987, the Zodiac signed himself "Yours truley" or "Yours truly" as an added signature. "Yours Truly" simply means "Me". Both were used in the Exorcist letter on January 29th 1974. "Yours truly" originated as a formal sign-off for a letter, a shorter version of phrases like "I am truly yours". Today, it is mostly used in a conversational or informal context to refer to oneself in a playful, humorous, or self-deprecating manner. I believe that when the Zodiac Killer mailed the April 20th 1970 letter and Z13 code, he gave us the answer of "My name is....Me" as a playful joke. He was taking the piss.

A solution created by converting ciphertext into plaintext from just 13 characters could never be verified, which is probably why he employed a different technique, inspired by the writings of Poe in Graham's Magazine in 1841. Those three circled 8's may have stood out for a reason. 
 
FOLLOW UP ARTICLE: THE SAME IDENTITY IN THE HALLOWEEN CARD 
FURTHER READING: AN IDENTITY DISCLOSED IN TWO LETTERS 

Four months had elapsed between the Melvin Belli letter on December 20th 1969 and the Z13 code on April 20th 1970, so what (if anything} inspired the Zodiac Killer to mail this most recent letter in April? For a long time I believed it was the newspaper coverage of Robert Salem's murder in San Francisco on the same day this letter was postmarked. However, this communication appeared like a response to a challenge laid down by Professor Donald C. B. Marsh, who told the San Francisco Examiner on October 22nd 1969 that "The killer wouldn't dare, as he claimed in letters to the newspapers, to reveal his name in the cipher to established cryptogram experts. He knows, to quote Edgar Allan Poe, that any cipher created by man can be solved by man. Zodiac has not told the truth in his cipher messages to the Examiner, the Chronicle and the Vallejo Times-Herald. Zodiac has not done this, because to tell the complete truth in relation to his name - in cipher code - would lead to his capture. I invite Zodiac to send The American Cryptogram Association a cipher code - however complicated - which will truly and honestly include his name". See article.

The newspaper story was entitled "Cipher Expert Dares Zodiac to Tell Name", so it seemed that this letter stating "My name is" was the Zodiac Killer's response to the challenge six months earlier. But why would the killer of five have waited half a year to deliver his response? Was there something significant about the data of April 20th? The challenge by Marsh and the invocation of Edgar Allan Poe's name, can be seen as a subtle prompt by Marsh to direct Zodiac down the path of encryption using techniques featured by Poe, thereby making any subsequent solve easier. It may have worked.

​George Rex Graham was the founder of Graham's Magazine, who hired Edgar Allan Poe as a critic and editor in February 1841. The magazine was the first to publish "The Murders in the Rue Morgue", "A Descent into the Maelström", "The Island of the Fay, The Mask Of The Red Death - A Fantasy", and others.

​Edgar Allan Poe's publication "A Few Words on Secret Writing" featured in Graham's Magazine in July 1841, showing different cryptographic methods, that began with the scytale method of decryption which can be employed to solve the 340 cipher. This was immediately followed by another cryptographic technique of splitting the alphabet into two lots of 13 characters, A through M, and N through Z, just like the Zodiac appeared to do with the Z13 offering. His code of thirteen characters began with A and ended with M, which when rotated by 8 positions on a circle, would create a signature later used in the Exorcist letter  This technique of using a cipher disk was another encryption method thoroughly covered in "A Few Words on Secret Writing"  Everything in Poe's publication in Graham's Magazine is instrumental to both the Z340 and Z13. But again, why would the Zodiac Killer wait six months to reply to the challenge of Professor Donald C. B. Marsh on April 20th, unless of course, this date was significant to Edgar Allan Poe and Graham's Magazine.  

On April 20th 1841 Graham's Magazine was the first to publish "The Murders in the Rue Morgue", a short story by Edgar Allan Poe, credited with being the first modern detective story. As the first fictional detective, "C. Auguste Dupin is a man in Paris who solves the mystery of the brutal murder of two women. Numerous witnesses heard a suspect, though no one agrees on what language was spoken. At the murder scene, Dupin finds a hair that does not appear to be human".Wikipedia. Bearing in mind that the Zodiac case was turning into an extremely intriguing mystery that confounded the likes of Detectives David Toschi and Bill Armstrong who searched tirelessly for the murderer of five, it's quite possible that the Zodiac Killer found it humorously apt to mail a code on April 20th based on Edgar Allan Poe's featured cryptographic methods in Graham's Magazine, which coincided with the release date of the first modern detective story, "The Murders in the Rue Morgue"..

​Professor Donald C. B. Marsh would offer the Zodiac a cryptic challenge on October 22nd 1969 invoking the name of Poe, with his coded reply possibly coming six months later on the exact day and month that Edgar Allan Poe, a prolific solver of ciphers, released the first modern detective story in Graham's Magazine. During 1970, the newspapers were filled with news of an impending Hollywood blockbuster entitled "Murders in the Rue Morgue" starring Jason Robards, Herbert Lom and Christine Kaufmann, to be released the following year. If the Zodiac Killer needed any reminder in April 1970 to the challenge given by Professor Donald C. B. Marsh, then the news of a movie to be released based on an Edgar Allan Poe short story, may have been the trigger. Not any movie, but "Murders in the Rue Morgue", initially published in short form on April 20th.

In the July edition of Graham's Magazine containing "A Few Words on Secret Writing", somebody mailed in a cryptographic challenge to Poe dated April 21st 1841, the same day and month Zodiac's Z13 cipher should have landed on the desk of the San Francisco Chronicle. The letter in Graham's Magazine introduced itself with the very same dash that followed the "My name is" introduction in the April 20th 1970 letter (see below). However, if the Zodiac Killer's initial trigger was "The Murders in the Rue Morgue", this subsequent date may have been a fortunate by-product. The "Sketches of Conspicuous Living Characters of France" and the mention of different languages (published in April), could be connected to "The Murders in the Rue Morgue", which was set in Paris, France - and in which - several of the witnesses reported hearing two voices at the time of the murder, one male and French, but who disagreed on the language spoken by the other. In other words, Edgar Allan Poe may have been continuing a theme in the April 20th edition of the magazine, to which the person below responded by dating his letter the following day and mailing it sometime later. This would effectively bind the two dates of April 20th and April 21st to the April edition of Graham's Magazine, If the Zodiac Killer had searched for cryptographic material on Edgar Allan Poe in 1969 and/or 1970, he may have found "A Few Words on Secret Writing" in the July edition of Graham's Magazine, which ultimately led him to the April edition and "The Murders in the Rue Morgue". Whether this is a viable route to the date of April 20th 1970 and the mailing of the Z13 code, is still open to question. 
​
The Mystery Writers of America (MWA) is a professional organization of mystery and crime writers, founded in New York City in 1945, which presents the Edgar Award, a small bust of Edgar Allan Poe, to mystery or crime writers every year. The Mystery Writers of America honors Edgar Allan Poe's groundbreaking work, particularly "The Murders in the Rue Morgue" as the foundation of modern detective fiction. The annual Edgar Awards, given by the MWA, are named after Poe in recognition of his role as the genre's inventor.

Michael Butterfield has covered the idea of Alfred Hitchcock Presents possibly having some influence on the Zodiac Killer, when the murderer stated in the "Debut" letter on August 4th 1969: "What I did was tape a small pencel flash light to the barrel of my gun. If you notice, in the center of the beam of light if you aim it at a wall or ceiling you will see a black or darck spot in the center of the circle of light about 3 to 6 inches across. When taped to a gun barrel, the bullet will strike in the center of the black dot in the light". He would back this claim up on November 9th 1969 when he wrote "To prove that I am the Zodiac, Ask the Vallejo cop about my electric gun sight which I used to start my collecting of slaves."  

In a series of 268 episodes running from 1955 to 1962, Museum Piece aired on April 4th 1961, in which a gun mounted sight on a .22 caliber rifle was used to aid in the hunting of victims, with a cursory mention of "The Most Dangerous Game" in the episode. The suggestion was that the Zodiac Killer may have watched Alfred Hitchcock Presents and used this sighting implement in his first attack at Lake Herman Road on December 20th 1968, before describing it in the "Debut" letter 7 1/2 months later.

Sir Howard Grubb (1844–1931) was an Irish optical engineer renowned for designing and manufacturing high-quality astronomical instruments, including some of the largest telescopes of the 19th century. He inherited and later expanded his father's company, cementing its reputation for precision optics. His innovations also included the invention of the reflector sight and improvements to the submarine periscope. In 1900, Grubb invented the reflector or "reflex" sight, a non-magnifying optical sight that uses a collimator to allow the viewer looking through the sight to see an illuminated image of a reticle or other pattern in front of them that stays in alignment with the device the sight is attached to (parallax free). This type of sight has come to be used on all kinds of weapons from small firearms to fighter aircraft.

​Using this principle, an "electric gun sight" was featured in the monthly publication of "Popular Mechanics" in the early 20th century. Michael Butterfield wrote "The Zodiac was not the first to conceive of a light attached to the barrel of a gun. Articles about a gun light had appeared in the magazine Popular Mechanics as far back as 1922 and 1933". However, the idea of an "electric gun sight" appeared in "Popular Mechanics" a little bit earlier than Michael suggested. The concept first appeared in "Popular Mechanics" in December 1908, and was featured in the San Jose Tribune, Bay Area newspaper on December 20th 1908, the very same day and month that Zodiac claimed he used an electric gun sight in his Lake Herman Road attack. The dates lining up is probably nothing more than coincidence, but it is noteworthy nonetheless.    

In a recent series of articles I attempted to show the thought process of one mind when exploring the feasibility that the Zodiac Killer may have composed communications in both Riverside and the Bay Area, through phrases such as "man is the most dangerous animal of all" and "it was about time for her to die". The thinking being that both the author in Riverside and the Bay Area used microfiche searches at the library when manufacturing the 408 cipher on July 31st 1969 and the "Confession" letter on November 29th 1966. One mind, therefore placing the Zodiac Killer in Riverside just after the murder of Cheri Jo Bates on October 30th 1966. The Confession letter author claimed "I am not sick. I am insane. But that will not stop the game", while the author of the July 31st 1969 letters referenced "The Most Dangerous Game" from 1932. But were there any signs of "Alfred Hitchcock Presents" in the Confession letter on November 29th 1966, therefore binding further the two authors? 

The Confession letter author typed "Miss Bates was stupid. She went to the slaughter like a lamb", yet they twisted the phrase "lamb to the slaughter", which comes from the Bible, specifically the Old Testament books of Isaiah and Jeremiah describing a righteous person being led to death without protest. The phrase symbolizes an innocent, unaware person being led to their own destruction. 

​In the Roald Dahl 1953 short story "Lamb to the Slaughter", the title serves as a dark, dual-meaning metaphor for Mary Maloney, who is initially an innocent, loving wife, but becomes the cunning killer who commits the act of slaughter with the leg of lamb itself. After murdering her husband with a frozen leg of lamb, she then cooks the meat to destroy any evidence and ends up serving the murder weapon in a dinner to responding law enforcement, who kindly oblige and eat the meal. While consuming the lamb, as Mary sits nearby but does not join them, the policemen discuss the murder weapon's possible location. One officer, his mouth full of meat, says it is "probably right under our very noses." I explored the possibility that the author of the Confession letter may have watched or read something about this Roald Dahl story, until I discovered that it had been made into an episode on "Alfred Hitchcock Presents" on April 13th 1958 under the same title of "Lamb to the Slaughter".  

If this phrase had been in the Confession letter author's mind when he typed this communication and subsequently mailed it to the Riverside Homicide Detail and Riverside Press-Enterprise newspaper, had he recently watched the Alfred Hitchcock Presents episode "Lamb to the Slaughter" in Riverside? Using a newspaper archive search in "Genealogy Bank" using the terms "Lamb to the Slaughter", "California" and the year "1966", I could find only three newspapers advertising this episode (using this platform), but crucially, all three were in November (and one was in Riverside).

​They were the Riverside Daily Press on November 5th 1966, Long Beach Press-Telegram on November 6th 1966 and Long Beach Independent on November 10th 1966. The show was due to air on Thursday, November 10th 1966 on KTLA (channel 5) from Los Angeles, about two weeks before the Confession letter author began typing the two Confession letters. It may have featured elsewhere in America during the year, but importantly, a Riverside resident could have viewed the episode "Lamb to the Slaughter" on television just fourteen days (or slightly more) before they typed "Miss Bates was stupid. She went to the slaughter like a lamb" into the Confession letters. It is impossible to say if a correlation exists between the two because we would have to know the mind of the author. However, if the Confession letter author did derive inspiration from "Alfred Hitchcock Presents" in Riverside in 1966, did this inspiration spill over to December 20th 1968, August 4th 1969 and November 9th 1969, when his "electric gun sight" took center stage? A murderer called Zodiac who possibly enjoyed murder mysteries. Who would have guessed.      

The Sierra Nevada mountain range straddles the border of California and Nevada, and encompasses the region of Lake Tahoe, the main focus in the "Pines" postcard mailed on March 22nd 1971, which gives us cryptic directions to the gravesite of Donna Lass. The young 25-year-old nurse went missing from the Sahara Tahoe Hotel & Casino in Stateline, Nevada on September 6th 1970, her whereabouts unknown until December 2023 when her partial remains were discovered about 20 miles west of Lake Tahoe's northern tip by a local fisheman.

During the prime Zodiac activity of letter writing between July 31st 1969 and July 13th 1971, the Zodiac Killer only ever laid claim to one murder outside of California, and that was Donna Lass from the state of Nevada. That is probably why the May 6th 1986 letter stated that the "body count" was growing all over the state of California and Nevada, despite abbreviating Nevada incorrectly. However, bearing in mind the only reasonable murder victim outside of California to be identified thus far was Donna Lass, who disappeared from a state that shares a border with California, it can be strongly argued that the Zodiac Killer was referencing the state of Nevada on May 6th 1986. The Zodiac Killer for the first time claimed the "body count" was growing, not the victim count. This may suggest that a body (or remains) had been found which consequently (and in part) increased the Zodiac total, rather than solely a confession of recent murders.          

The May 6th 1986 letter was claiming the recent double murder of Laotian couple Koy Ien Saechao (48) and Choy Fow Saelee (40), who were gunned down in their 1983 Mercury Cougar near the interchange of Highway 99 and I-5 in Sacramento by 15 small caliber bullets. They had been murdered between 3:15 am and 7:30 am on April 22nd 1986, in what appeared to be a motiveless and random attack. The Zodiac Killer was claiming these latest killings in his total of 100+, but didn't write "the victim count is growing all over the state of California and Nevada", by instead choosing to write "the body count is growing all over the state of California and Nevada".

​This may be extremely telling, when you consider that the remains of Donna Lass were discovered in late December 1985 and January 1986, yet she wasn't identified until December 2023. In other words, when both the skull and jawbone were discovered by January 19th 1986, nobody was aware that they were the remains of Donna Lass but for her killer. So it's quite remarkable that the Zodiac Killer referred to a "body count", including the state of Nevada for the first time, just three months after the discovery of her remains.

​The previous victim count announced by the Zodiac Killer dated back to the "Exorcist" letter on January 29th 1974, which amounted to a duration of over 12 years. To put this into perspective, the Zodiac Killer was now claiming a new "body count" that included Nevada, only three months after the remains of Donna Lass were found, 147 months after his last victim total. That is impeccable timing or extremely fortuitous, to not only invoke the word "body" in his count, but to include the state of Nevada where Donna Lass went missing from.          

The last time the Zodiac added a "plus" sign after his running kill count was when he wrote "17+" on March 13th 1971, insinuating the distant murder of Cheri Jo Bates in Riverside on October 30th 1966, about 4 1/2 years previous. The "plus" sign probably denoting the belated addition of this victim from many years ago. He did exactly the same on May 6th 1986, a few short months after the remains of Donna Lass were found, nearly 16 years after she was likely murdered. The addition sign used in 1986, when he wrote "the body count is growing now 100+", could mean exactly the same thing - that we should be looking for a long dead victim in Nevada in this instance, rather than Riverside. Two distant murders, both accompanied by a retrospective "plus" sign, may be suggestive that law enforcement (SFPD) should now credit each of the belated discoveries to his, the Zodiac Killer's running victim total. It must also be noted that the March 13th 1971 and May 6th 1986 letters were the only two Zodiac communications to sign off in this fashion (and order), with the mocking SFPD = 0, followed by the crosshairs and a hyphen, and then the running victim total and addition sign (see below).        

The newspaper articles above highlight a "Skull found in Sierra" and "Human remains found in Sierra" by Melvin Bennett in "two inches of snow", so it's pertinent to recollect how the Zodiac chose to emphasize the upside-down phrase "around in the snow", while using the "Sierra Club" pasting as a place marker on the "Pines" postcard. It is fairly clear at this point that the March 22nd 1971 "Pines" postcard with directions such a "pass Lake Tahoe areas" and a punch-hole, was pinpointing the location of Donna Lass' burial site. Factor in the observations made about the 1986 letter above, with the calculated measurements of the postcard which clearly showed the punch-hole landing squarely over the area her remains were found, and we seemingly have an author who knew exactly the burial location of Donna Lass, and the time period the skull and jawbone were found by Melvin Bennett and a later search party, headed by Deputy Lowell Carleton. Why would the Zodiac Killer mention the state of Nevada in 1986 if not for the recent breaking news? Only the killer of Donna Lass would have recognised this location as relevant to her murder and burial site. 

FINDING THE LOCATION OF DONNA LASS' REMAINS USING THE PINES CARD