Yeah, the symbol was printed in the paper - it says so earlier in the thread.
smithy wrote:... in one of the textbooks about handwriting disguise (was it Springer or Koppenhaver or W. Harrison? I don't know - it was one of them) they talk about zoned letters and slant and size and stuff, but also about using circular periods....
Found it. Was I the only one looking? Perhaps I was! Damn! Well, we all need a hobby.
http://scholarlycommons.law.northwester ... ntext=jclc There. John J. Harris. It's worth reading - even this little excerpt's good.
This is the handbook that smart policemen and fledgeling forensic technicians would have been perusing in the 50's and 60's.
There's a better one which was released in 1970, which has even more recognisable "techniques" in it.
Oh! Of course smart criminals would have read it too. If you happen to believe that The Evile Zodiace was a smart criminal, that is.
(Did the guy spend all the time between vicious crimes in the library, studying bomb-making, ciphers and What-News-Editors-Want? Hmm.)
Anyway, what I'm trying to say is that if someone wanted expert advice on how to disguise their handwriting they'd use some of the techniques the book mentions. Indeed, "Lo and behold!" - it certainly seems our letter-writer uses damn-near ALL of them at one time or another, it's been suggested. Even "upside-down" writing. No, it's not a coincidence.
The car door, then!
The car door contains one immediately recognisable techinique "for handwriting disguise" which was known and talked about in educated document-examination circles of the time, then. That there colon. And (bonus!) it was also used - occasionally - in other (unpublished) letters.
I would tend to believe that Sherwood Morill would have recognised that. At least I would like to.
It's almost like another of the writer's little taunts isn't it - using techniques he knew the police would recognise? What a rotter.
Am I repeating myself? Apologies if I am.