Well, despite many careful edits of the manuscript, and hundreds of readers since the book's publication two years ago, no one (including me) has noticed that I messed up the coded bit in a couple of places. Until now!
The delightful and clever Pam Stucky, herself a novelist and apparently a fan of deciphering codes, recently read The Ghost Downstairs and set herself the task of decoding the journal excerpts before the narrative did so for her. (You don't need to do this to enjoy the novel--I give you the answers, so to speak, after a few pages. Homework not required.) And she found that in my transcription of the coded text, I inserted the wrong letter in at least two instances. Oops.
It also occurs to me that I listed the decoded alphabet in the wrong order if we're doing it from the point of view of the cryptanalyst (the one breaking the code) and not the cryptographer (the one creating the code). Ah, well. Again, doesn't affect the story much.
Still, for being so diligent and for catching out my editors and me, Pam gets a free book of her choice (of the ones written by me, that is). Plus I recommend you check out her debut novel, Letters from Wishing Rock, a charming epistolary story (composed of emails, not paper letters, this being the modern era), peopled with an armful of likable characters, and set in the Pacific Northwest, Scotland, and other beautiful places. It has a "Northern Exposure" feel to it that I really enjoyed.
Keep being smart, o friends o' mine!