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Mystery Cache

Puzzle Solving 101 - Lesson 8: Steganography

A cache by ePeterso2 Send Message to Owner Message this owner
Hidden : 9/11/2007
In Florida, United States
2.5 out of 5
1.5 out of 5

Size: Size: micro (micro)

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Geocache Description:

South Florida Geocachers

About This Series

The first nine caches in this series will help you build your puzzle-solving skills. Each one contains a lesson focusing on a specific skill, examples of how to use that skill, an exercise to test that skill, and a cache to find as a reward. Study the lesson, complete the exercise, and you'll find the location of a geocache.

Each of those caches contains a piece of information you'll need to take the final exam (the tenth cache in the series). Bring some way of recording those clues for later ... paper and pen/pencil would come in handy, or perhaps a camera. (A hammer, chisel, and very large rock would work but probably wouldn't be very handy.)

Lesson 8: Steganography


This series of caches has discussed a number of different types of puzzles commonly used to hide geocaches. But some of the most difficult-to-solve puzzles are created using a method known as steganography.

Steganography means literally "hidden writing". It is similar to cryptography in that it is used to send a message so that only the intended receiver can make sense of it. Whereas the purpose of cryptography is to scramble a message into unintelligible gibberish, the purpose of steganography is to keep unintended recipients from discovering that a message even exists at all.

A steganographic message appears to be something else, typically something common and innocuous. A message can be a letter, an article, a shopping list, a photograph, an audio recording, or some other form. This apparent message is called the covertext.

To create a steganographic message, the plaintext is typically encrypted in some manner using a cipher to create the ciphertext. This ciphertext is then embedded into the covertext to create the stegotext. The stegotext is often surrounded with nulls, which are extra pieces of information not part of the hidden message but which are included to increase confusion and distraction for those seeking the message.


Probably the best way to understand this process is with some examples:

  • One of the most well-known steganographic tools is invisible ink. A secret message may be written in invisible ink over top of the cover text; to read it, the recipient would hold the cover text up to a particular shade or intensity of light. (Remember the opening scenes of The DaVinci Code?)
  • In ancient Greece, wooden tablets covered with layers of wax were often used as the medium for writing messages. A secret message could be hidden by writing the message directly on the wood before covering it with wax. The recipient would then simply melt the wax to read the message.
  • Also in ancient Greece, Herodotus tells the story of a message tattooed on a slave's shaved head, hidden by the growth of his hair, and exposed by shaving his head again. The message allegedly carried a warning to Greece about Persian invasion plans.
  • During World War II, a spy for the Japanese in New York City, Velvalee Dickinson, sent information to accommodation addresses in neutral South America. She was a dealer in dolls, and her letters discussed how many of this or that doll to ship. The stegotext in this case was the doll orders; the 'plaintext' being concealed was itself a codetext giving information about ship movements, etc.

Unfortunately, due to the extremely wide variety of methods that can be used to encode information, there is no easily generalized method of performing steganalysis. This is why these categories of puzzles can be so infuriating. Here are some places to look for clues:

  • Look in the body of the stegotext. It may have clues that indicate the type of information contained. Things in the stegotext that seem odd, inexplicable, or otherwise out of place (no matter how slightly) may also be indicators that they hold the key to the secret information.
  • Look inside the digital message. Executable, image, and audio files often have methods of including information that describes the contents of the file that are not directly part of the content of the file. For instance, an MP3 file can contain the name of the song, artist, and album, although none of those things changes the audio playback of the file. A secret message could be hidden in any of the extra fields of such a file.
  • Get to know the sender and the receiver. Knowing something about the individuals transmitting and receiving the message may uncover information about how to decrypt the message.
  • Use the tactics described in Lesson 2 of this series to find clues. Look for things that may hold patterns of coordinates or clues to container sizes or hints as to hiding spots. Especially watch for things that fit into some kind of overall repetitive pattern.

Exercise 8: Dr. Spock's Backup Band

Six Questions for They Might Be Giants

By Cecil Portesque, NPR's Duke of Dead Air

Born in Raleigh, NC, and raised in Columbia County, NY, Cecil Portesque has They Might Be Giants in his blood...even though he admits he loves Weezer too. Like his arch-nemesis Bill O'Reilly, Cecil attended college but never matriculated. Even "hippie" college Bard was too many rules for his free spirit to bear. Cecil ALWAYS listened to late night radio (starting with WABC's "Good Guys" late at night) but the idea of being on the radio didn't cross his mind until he worked as an intern at a public radio station in the mid-1980s during a fund drive. As his political awareness rose and his respect for the politically correct broadcasters fell, he figured he could do it, too! When someone at WBAI, New York, couldn't make the overnight slot, Cecil was ready to fill in. And so the career of the "Duke of Dead Air" began!

Cecil spent most of the '80s and '90s lost in what he describes as the "Bermuda triangle" of New York public radio. Stints behind the microphone at WBAI, WFMU and WFUV finally led to paying work as a consultant for Sirius, where he programs a variety of the alternative-music channels. Encouraged by longtime engineer and TMBG archivist Julian Dufy to return to the other side of the glass, Cecil brings back some of his late-night magic to They Might Be Giants podcast. Cecil says of his new gig: "TMBG's music is original and I love their energy. Working on these podcasts is a dream for me."

CECIL PORTESQUE: Welcome. It's a beautiful day outside, it's a beautiful day inside. As regular listeners of my show know, it's time to play Six Questions. My guests today are just a couple of guys from Brooklyn, New York. Of course, I'm referring the little duo with the big name: John Linnell and John Flansburgh of They Might Be Giants. Thank you agreeing to be on the show, and good ... uh ... afternoon to you both.

JOHN LINNELL: Good afternoon.

JOHN FLANSBURGH: Good afternoon to you, Cecil.

CP: All right, let’s begin. So, John: when you first started recording and, ... uh ... performing together, you used recorded drum and synth tracks instead of a band. How did that affect your future music?

JF: Was that directed to me?

CP: Uh … either one of you.

JL: Why don’t you field that one, John.

JF: Okay, well … huh. Well, we would have loved to have had a band early on, but at the time we were just playing in our living rooms and were pushed into clubs by friends that loved our music. So we just brought the drum machines and tape recorders that we were using at home into the clubs and studio with us. That let us get away with layers of sound, like on “Put Your Hand inside the Puppet Head” – that’s a song we could never perform live with just a guitar and accordion.

CP: Ah.

JL: But playing with a tape over and over was terribly … limiting, too. While it gives you the ability to perform with a smaller number of band members, it also constrains what you can do live. So we looked for creative ways to kind of break out of that mold a bit, such as during the Flood tour when we used nothing but a metronome for percussion on “Where Your Eyes Don’t Go” … it was kind of a minimalist response to the drum track.

JF: Right, I mean, where you really saw the limitations of taped accompaniment was with a song like “Someone Keeps Moving My Chair”. When you play a song like that live, you want to change the tempo to go with the flow of … energy, I suppose … that the crowd is giving you. But the energy of the tempo on tape might not be what the audience is in the mood for that night, so … y’know.

CP: Energy flow … let’s go with that. What range of ... uh ... energy does a typical audience expect from you?

JF: That depends upon the city.

JL: And the type and quantity of illegal substances consumed by the audience prior to the show.

JF: Right, like, when you play for the potheads in Los Angeles, even something as melodramatic as “Narrow Your Eyes” can get them excited, whereas you’ve got to pump it up with something like “AKA Driver” to keep the dance floor moving for the crack heads in Detroit.

CP: Really.

JF: No, not really.

JL: Although, I can’t envision any combination of city and controlled substance that would receive “How Can I Sing Like a Girl?” very well.

JF: Word.

CP: Okay, so, ... what do you do when you aren’t writing music?

JF: Well …

JL: That’s sort of one of those unanswerable questions, like “What do you look like when your eyes are closed?” I mean, writing music something we do every day, as naturally as breathing.

JF: Sure, I mean “Operators Are Standing By” was written while I was on hold on my cell phone in the car. Do you realize how difficult it is to drive and write a song at the same time? Especially with a Martin acoustic in your hands?

CP: But you’ve also performed songs that you didn’t write.

JF: Is that question four?

CP: No, it’s an elaboration, not a question.

JF: Oh. Well, sure, I mean sometimes when you hear a catchy tune you really like and you think to yourself, “Wow, we could put our own unique spin on that” or “That really meant something to us”, then it’s hard not to respond to that call. And as long as you get permission and pay the licensing fees to the publisher, it’s all good.

JL: Right. For instance, we remade the song “Yeh Yeh” for Mink Car and did our due diligence with licensing and all, and we were sitting in John’s living room watching TV one night when a Ford commercial came on with that song playing on it! Of course, they’d never gotten our permission, much less the permission of the original publisher … they were cool about settling out of court, though.

JF: Yeah, fortunately, their lawyers are all big TMBG fans.

JL: The funny part about Ford's legal team was that they had this abnormally strong love of the song “The House at the Top of the Tree”. I’m not sure why.

JF: Probably because of the lyric about the dog. Everyone likes dogs.

JL: Indeed.

CP: Let’s get back to the interview. Video. It’s always been a big part of TMBG, as you guys kind of surfed the ... MTV "wave" back in the late 80s and early 90s. What is video like ... for you now?

JF: Well, the best part is that other people do all the hard work for us! For instance, shortly after the release of The Spine, the guys over at Homestar Runner cranked out a Shockwave animation for “Experimental Film” which was just so wonderful, better than any ideas we were kicking around at the time.

JL: Yeah, it came out a lot better than the traditional TMBG video fare, which largely consists of us jumping around in a synchronized fashion.

JF: Absolutely. And with the expansion into children’s music that we’ve begun, working with Disney has only expanded our possibilities and opportunities for self-expression.

JL: I think my favorite kids video we’ve done lately is “Q U”.

JF: Really? Why?

JL: Because it’s my son’s favorite … it keeps him distracted while I work on new songs.

CP: New songs, ah ... new songs. While touring after the release of The Spine, you wrote a new song every day for every venue you played. What is it like to work under that kind of pressure?

JL: Well, like everything else, it's sort of a double-edged sword ... it has a lot of the yin-yang thing going for it. On the negative side, it just adds to your workload, which is already pretty considerable while touring, a lot more than when you're working in the studio. But on the plus side, it's invigorating - I enjoy challenging myself, and being forced to produce in a very immediate way brought out some ... creative karma that I don't think we knew we had. Maybe John could explain that better ...

JF: Oh, absolutely. It was tough to do, and we didn't always execute very well. But occasionally a few gems emerge from the rough ... I think "Glasgow (T-H-E-G-A-R-A-G-E)" was one of my favorites not only because it's a catchy tune, but also because it meant a lot to the audience there at the time.

CP: I see.

JL: And that situation was a big contrast to our most recent album, The Else. I think we were so burnt out by the end of the Venue Songs tour that we wanted to take a more ... measured approach to production. It has a very different sound, one that's a lot more polished and thoughtful. I think "Climbing the Walls" is one of the better examples from that album ... it has a lot of subtlety in the production that you don't hear directly unless you're really paying attention, but which ultimately really kind of shapes the sound in some interesting ways.

JF: And that's going to continue to be a part of our sound for some time to come, especially with the release later this year of our next children's album called Here Come the 123s ... you may have already heard the song "Seven" which is airing now between shows on The Disney Channel.

CP: I can't say that I--

JULIAN DUFY: Time check, Cecil. Wrap it up.

CP: Oh! All right, well, it's time to wrap things up. At Six Questions, we have a tradition here; we like to end the interviews with a question Jann Wenner liked to end his interviews at Rolling Stone with. If you were to die, what would you like the angels in heaven to say about you?

JF: Hmmm ... probably "When you wanted rock, They rolled."

JL: I think I'd like them to say this: "By paying attention to Their songs, Their fans always knew where to find Them."

CP: All right. I want to thank my guests John and John of They Might Be Giants for being on my show to play Six Questions. Thank you both for coming by the studio today.

JF: Thank you, Cecil.

JL: Yeah, thanks a lot.


I had the good fortune to see They Might Be Giants during their stop in Fort Lauderdale on the Beardo 2006 tour. I even wrote a review of the show for

You really should check out the Homestar Runner video for Experimental Film.

If you can solve this puzzle, you might be ready to tackle this.

Additional Hints (Decrypt)

[Puzzle] Bxnl, fb vg'f xvaq bs n gevivn punyyratr, gbb. Lbh zvtug svaq jjj.gzoj.arg gb or n urycshy erfbhepr.
[Puzzle] Bayl hfr Gurve shyy-yratgu fghqvb nyohzf, cyhf gur PQ sebz gur Irahr Fbatf QIQ/PQ frg (juvpu unf fghqvb erpbeqvatf, nf bccbfrq gb gur ZC3 qbjaybnqnoyr irefvba, juvpu qbrfa'g).
[Puzzle] Gra vf mreb.
[Puzzle] Zbfg crbcyr frrz gb trg uhat hc ba trggvat gur 11gu qvtvg evtug. Vs Trbpurpxre fnlf lbhe fbyhgvba vf vapbeerpg, purpx gung bar svefg.
[Cache] Zntargvp uvqr-n-xrl ba obk #17 va gur funqbjf bs jung zvtug or tvnagf. Jngpu bhg sbe gur fyrrcvat tvnag arneol.

Decryption Key


(letter above equals below, and vice versa)



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Last Updated: on 2/5/2016 7:24:50 AM (UTC-08:00) Pacific Time (US & Canada) (3:24 PM GMT)
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