Awesome episode! Lot’s of tidbits that I have never heard about before. The ironic thing is I had just purchased a 1st edition of the book Harden reportedly consulted (Secret and Urgent by Fletcher Pratt) shortly before Youtube alerted me to your video.

Great episode and very lengthy, impressive! Everything is crystal clear.

Good chance that the Hardens sent the code key: http://www.zodiackillersite.com/viewtop … =75&t=4088

Great episode and very lengthy, impressive! Everything is crystal clear.

Thanks, Jarlve!

Good chance that the Hardens sent the code key: http://www.zodiackillersite.com/viewtop … =75&t=4088

Your analysis there is very interesting. The strongest piece seems to be the FBI mentioning "school teacher" in connection to the code key (I assume they aren’t referring to a different school teacher). But it’s still weird. Why would he send it anonymously right after he was already outed as the solver? And the errors don’t seem to line up with his known worksheets. Some newspapers showed different versions of the worksheets.
Direct link to errors discussion in my latest video: https://www.youtube.com/watch?v=57o8g3d6lSw&t=34m52s
Many of the discrepancies related to the Harden worksheets are in the annotations here: http://zodiackillerciphers.com/408/key.html
One of them stands out: "Harden appears to have originally considered Q and backwards Q to be the same symbol". The concerned citizen key seems to reflect the same error. But why did he also think plaintext K and L were replaced by Q?

Thankz doranchak,
Totally enjoyed your report & your presentation.
Zam*

Join me for a deep dive into the Zodiac Killer’s first mysterious cipher, as told through a combination of newspaper articles, police reports, FBI documents and books.

Nice quality, clear, well done video. How many hours did you put into making this video?

Who do you think sent the Key Card?

Nice job!

How many hours did you put into making this video?

When I started making it, I thought I’d be done in a week or two. But the project quickly expanded and ended up taking me over three months.
Not sure how many hours that represents though – it was a lot of pre-dawn and weekend work outside of my day job.

Who do you think sent the Key Card?

My feeling is that it’s just someone who saw the plaintext printed in the papers and then worked up the key on their own, sending it the very next day, in an attempt to be helpful. Jarlve brings up some good points about how it might have been Harden, although I have trouble resolving why he would have sent it. His ongoing interviews with newspapers, mentioning his name, continued to be published days after the anonymously sent key was received by VPD.

Great video as always & a very easy to follow.
What i found interesting is the San Francisco man that phoned in to say he decoded the last portion of the cypher as Robert E EEEE.
Now i thought straight away that could mean Robert H West, then i noticed who the caller was & that was also Robert H then blank for his surname…could this have been Robert Hale West calling in?

Great video as always & a very easy to follow.
What i found interesting is the San Francisco man that phoned in to say he decoded the last position of the cypher as Robert E EEEE.
Now i thought straight away that could mean Robert H West, then i noticed who the caller was & that was also Robert H then blank for his surname…could this have been Robert Hale West calling in?

Oh, great video again Dave. As always, well explained.

Oh, great video again Dave. As always, well explained.

Thanks Richard!
BTW where are you getting the non-redacted VPD report?
The copy I have blacks out his surname at the top but they evidently forgot to black it out later in the same paragraph, lol

That solves that the caller part cheers Richard.Still might be a reference to Robert H West for the cypher but who knows.

I cannot locate the original file at the moment, but I got this from here.
http://www.zodiackillersite.com/viewtop … =47&t=1797

Why would he send it anonymously right after he was already outed as the solver? And the errors don’t seem to line up with his known worksheets. Some newspapers showed different versions of the worksheets. But why did he also think plaintext K and L were replaced by Q?

As discussed previously, it is possible that the letter was mailed before the outing. Try to imagine the state of mind the Hardens were in after pulling some all nighters and actually solving the killer’s code, presumably being the first ones to do it. They must have been in doubt on how to handle it. Be public about it or be anonymous? The code key may have stemmed from an even earlier worksheet that had more errors.

The August 9th 1969 San Francisco Chronicle article stated "Vallejo Police Sergeant John Lynch, in charge of the investigation of the murders and of the cipher letter writer, asked The Chronicle to send Harden’s code breaking worksheets to him for further checking; which was done." The author of the ‘Concerned Citizen’ card had used the same clumsy wording present in this article, when he addressed Sergeant John Lynch at the Vallejo Police Department. The ‘Concerned Citizen’ card stated "Dear Sergeant Lynch. I hope the enclosed "key" will prove to be beneficial to you in connection with the cipher letter writer. Working puzzles criptograms and word puzzles is one of my pleasures. Please forgive the absence of my signature or name as I do not wish to have my name in the papers and it could be mentiond by a slip of the tongue. With best wishes. concerned citizen".

The idea that the ‘Concerned Citizen’ would just happen to accidentally use this uncomfortable array of wording, such as "cipher letter writer", and didn’t read the San Francisco Chronicle article one day before his August 10th 1969 card seems unlikely.