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200-Year-Old Cipher Finally Cracked

Attila Dimedici writes "A code expert just cracked a code used by a friend of Thomas Jefferson in a letter written to Jefferson some 200 years ago. This code is fairly easy to crack using a computer, but extremely difficult without one. I think it would have been much harder if the author had not included an indication as to what code algorithm he used in the letter accompanying the coded message."

19 of 141 comments (clear)

  1. tl;dr by Anonymous Coward · · Score: 5, Informative

    The message says:

    "In Congress, July Fourth, one thousand seven hundred and seventy six. A declaration by the Representatives of the United States of America in Congress assembled. When in the course of human events..."

    1. Re:tl;dr by morgan_greywolf · · Score: 5, Funny

      FTFA:

      After about a week of working on the puzzle, the numerical key to Mr. Patterson's cipher emerged -- 13, 34, 57, 65, 22, 78, 49.

      Hey! That's the combination to my luggage!

    2. Re:tl;dr by mobby_6kl · · Score: 3, Funny

      Phnglui mglwnafh Cthulhu R'lyeh wgahnagl fhtagn!

  2. Wake me when the Voynich is cracked by netsavior · · Score: 5, Interesting

    the Voynich manuscript is a much more compelling and difficult mystery.

    1. Re:Wake me when the Voynich is cracked by jd · · Score: 4, Insightful

      Perhaps, but there's no evidence that the Voynich manuscript is a cypher in the traditional sense. A natural language isn't normally "decyphered", since it was never encrypted in the first place.

      Given that there are many hundreds of thousands of natural languages today for which there is no written form, it's entirely possible that this is a script invented for such a language. In WW2, natural native American languages were sometimes used in this way as an "unbreakable cypher" - who's to say that medieval Europeans hadn't done the same thing themselves?

      If that is the case, then it isn't particularly compelling (we know of many extinct languages for which no known writing exists - and hundreds more go extinct yearly), and is not so much "difficult" as useless - the text could never be read.

      The wikipedia article doesn't say anything about using techniques to detect writing that is no longer visible, so I must assume no such techniques have been used.

      (It may be possible to establish some of the content of a missing page if the page after had been underneath at the time of writing. Non-destructive techniques for doing this formed a part of the case against the West Midland's serious crime squad in the 90s, where it could be shown pages of confessions had been altered after being signed. However, if no such analysis has taken place, the presence of such data is unknown.)

      Regardless, there are many missing pages. From the articles, the page numbers seem to be relatively new compared to the text, so we don't know how many pages are actually missing, we only know how many went missing since being numbered. This makes understanding the text very difficult and even if the text could be translated, there's no guarantee we could even read it or understand it without those pages.

      We know vastly more about Linear A than we do about the script on the Voynich manuscript, including the archaeology of the people writing Linear A, yet after all this time we've got no further than knowing the number system and a few of the numbers in it.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    2. Re:Wake me when the Voynich is cracked by netsavior · · Score: 3, Insightful

      First of all, The Voynich is only 500 years old(give or take), from a time when books were not uncommon, and was very very likely written in Europe, hardly pre-historic. This would be a person in Europe, with contemporary writing, art, and binding supplies, writing in a dead language not otherwise documented anywhere else. Linear A is like FOUR THOUSAND years dead... not really comperable.

      That is what makes it so compelling, the fact that it happened, not in a vaccum like the Aboriginal Amazon, not in ancient history like Linear A, not in Stone, or papyrus, or etched on tree bark, but that it happened inside of western society, using "modern methods" (for the day), and it is a language/code that can be verified as not being junk, but that nobody had seen before or since.

    3. Re:Wake me when the Voynich is cracked by Yvanhoe · · Score: 3, Interesting

      Many words in one of the syllabic alphabet (katakana) have a pronunciation close to english, as they are foreign words phonetically transcribed in Japanese, like ko-n-pu-ta (computer)
      Even without that, it is easy to tell apart the complex ideograms and the syllabic characters, if only because of their frequency of appearance. There are some structures easy to spot : polite forms and declarative sentences end frquently by the same words, etc... There are many structures that are easy to spot. I suspect it is the case in any language. The Voynich doesn't appear to obey to any grammar structure. Such a problem ought to be easy : there is a whole book, presumably about plants, and we don't even manage to find a single common word in all these pages that could possibly mean "plant" ? Or "root" ? Or a single sentence structure common to many places ? My bet is on "nonsense written by someone who wished he could write and had an instability making him believe he could"

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
    4. Re:Wake me when the Voynich is cracked by Canazza · · Score: 3, Funny

      Lorem Ipsum dolor sit amet...

      --
      It pays to be obvious, especially if you have a reputation for being subtle.
  3. just cracked?? by macxcool · · Score: 5, Informative

    A code expert just cracked a code

    The article says "After unlocking its hidden message in 2007". This is hardly 'just'. The solution was more recently published though. Interesting article.

    1. Re:just cracked?? by gEvil+(beta) · · Score: 5, Insightful

      What? You actually expect the article submitter to RTFA?

      --
      This guy's the limit!
    2. Re:just cracked?? by bitt3n · · Score: 4, Funny

      A code expert just cracked a code

      The article says "After unlocking its hidden message in 2007". This is hardly 'just'. The solution was more recently published though. Interesting article.

      he's obviously using the same definition of "just" that I use when I tell my wife I just took out the garbage so get off my back

  4. Contents of message by wjousts · · Score: 5, Funny

    "Hey Jefferson, you might want to try keeping it in your pants. I saw that slave girl today and she's starting to show. People will start asking questions."

  5. Re:Security by obscurity by phantomfive · · Score: 5, Insightful

    Obscurity IS a level of security, which is good, but it's only one level. Hopefully you have a security system that is robust enough that even when the obscurity is pierced, it is still secure. In the past when people complain about Microsoft depending on security through obscurity, they were referring to the fact that Windows was at one time so insecure that it was only a matter of obscurity that gave it any security at all. That isn't to say obscurity is all bad for security.

    In this case, unless you knew the key, it would have been extremely time consuming to discover the solution, even if you knew the algorithm used. Notice it took the guy a week to solve it, even with a computer, and modern cryptanalysis techniques.

    --
    Qxe4
  6. Re:Biggest letdown ever by 0racle · · Score: 3, Insightful

    Most likely for the reason that was presented at the end of the article, it was for a bit of fun. It was meant to be an exercise in cryptography, by enciphering something Jefferson knew, he would know when (if) he deciphered it correctly.

    --
    "I use a Mac because I'm just better than you are."
  7. The trick was finding the decoder ring by rev_sanchez · · Score: 4, Funny

    The message was: "Be sure to drink your Ovaltine."

    --
    If you didn't come to party don't bother knocking on my door. Prince '1999'
  8. Fine, but... by 93+Escort+Wagon · · Score: 3, Funny

    ... it's not going to do much good for President Jefferson at this point.

    --
    #DeleteChrome
  9. Could have been done earlier by houghi · · Score: 5, Funny

    ... but they had to wait for the copyright to expire.

    --
    Don't fight for your country, if your country does not fight for you.
  10. Zodiac Killer 360 by Korey+Kaczor · · Score: 5, Interesting

    The elusive Zodiac Killer's 360 character cipher was never cracked, either, and it's been decades since he mailed it to newspapers. That cipher also seems a bit grid-like, with spacing made deliberately in rows. I wonder if this method would help, at least in part, in cracking it?

    If anything, would be nice to see something come up to ascertain his identity, and if alive, put him behind bars.

  11. Jefferson wrote the Declaration of Independence by tyrione · · Score: 4, Interesting

    He wrote the entire draft. The only parts that changed were minute portions and the choice of language he used was replaced by less forceful language for fear of being too alienating to the common man. The WSJ cites him as a contributor. The author needs to read Jefferson's letters. It's right in there. I suppose Stephen King or any other author should be called a contributor to their work after an Editor comes in and helps modify it.