Mary’s roving book party and ciphers

Some of the code breaking from last night's launch party for GHOST TALKERS.Today, I’ve already had a couple of people come up to me with the correct passphrase for my roving launch party. Here is where I should make it clear that though I said the party is tomorrow, it’s actually all weekend. Except that tomorrow is the day that I’ll be in costume.

Perhaps it might be helpful for you if I talk about a couple of different types of ciphers and codes and the ways that spies passed messages back and forth. Okay…here’s an excerpt, which I hope you’ll accept as being out of context.

Mrs. Richardson asked, “Are there really codes based on the weather?”

Ben laughed, and a bubble of amusement floated up from Merrow. Ben said, “Th e weather. Fish. Th e number and length of pauses you take in a sentence. I once knew a fellow who could stammer in Morse code. It was quite impressive. Another woman used the length of stitches in her dresses to carry messages. I used to carry cigars that had onionskin paper tucked inside. Lived in fear of grabbing the wrong one and smoking my secret message.”

Merrow said, “Remember the baker, sir?”

“Right!” Ben rubbed his mouth, grinning. “We had a live drop who signalled that he had a message waiting by the number of pastries in the window. You had to let him know you were the contact by ordering a specific grouping of pastry. Damn good pastries. Pleasantest password exchange I’ve ever had to do.”

So what’s a live drop? That’s when you actually talk to your contact, usually through an exchange of passwords. Coming up to me and giving me the passphrase from the roving launch party post, will trigger an exchange. An exchange. Right. Delivering the passphrase means you’ll get something in return.

It might be written in plain text. Sometimes it’ll be a cipher.

A cipher is when numbers, letters, or symbols are substituted to create text that is unreadable except to someone who knows the key.

Common ciphers still abound in everyday use. One example, in use on internet forums today is rotational 13. Most people know that as rot13. Meaning that it’s a type of Caesar cipher in which the alphabet is rotated, in this case by 13 spaces. Once you rotate the alphabet A becomes N and so on. Now, you can do a Caesar with any number of rotational spaces.

Cracking a common Caesar is fairly easy to crack by brute force, which means that you just keep trying rotations until you run through them all. Above that in difficulty level is a “keyed Caesar” in which a phrase goes at the beginning of the alphabet. Every letter not used in in the key get rotated to the end. So, I was going to do one in which a rot7 returned “E tu Brute” and then if you said that passphrase to me, I would hand you the next code and say, “Caesar rot in hell.” As an example, the rotation then became INHELABCDFGJKMOPQRSTUWXYZ.  Rather sadly, as fun as that bit of verbal humor was, in trials no one got it.

Of course, there are also skip codes, book codes, columnar codes, double-codes like the Navajo code talkers who were writing messages in Navajo which was then run through a cipher as well. Kinda a there’s a ton of cool stuff, huh?

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3 thoughts on “Mary’s roving book party and ciphers”

  1. I’ve finished the book! Would that I was there to take part in the party, but alas I’m on my own couch.

    I’d actually forgotten the ending, so reading it again was a nice surprise. As was the page after that. <3

  2. I’ve always wanted a pen pal with whom I could use a one-time pad to exchange encrypted notes. Until our pads ran out. Then our relationship would be over.

  3. Before anything else, let me say how much I’ve enjoyed Ghost Talkers! Using ghosts as a way to determine troop movements and to spy on the enemy is such a cool idea. Thank you for writing it! Well, your book also made me cry, but that only improved the experience. Hope you’ll have and have already had a great launch party!

    I also really liked the way Ginger and Ben communicated via ciphers. Creating the poems and their hidden codes must have been tricky and a lot of fun. Here on your blog, it’s also great fun to decipher them.

    Bye the way, I’ve tried and failed to solve the book code. Only a desperate last-ditch attempt will help me, I hope…

    Oh anyway, thanks a lot for all of this 🙂

    Kathrin

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