franklin,
I doubt 1 in 100 Beale fans would have caught that. You have done your homework.
Even though Singh's book sits only a few feet from my screen, I don't think I have read that portion of the book since I got it in 2002 or 2003. I'm not really a big fan of that mystery.
When you read through the impressive list of cryptanalysts, including Singh, the NSA and the best code breaking computers in the world, it is hard to believe the cipher has not been broken.
Have to admit, I really enjoyed his book.
Nice catch,
Joe Ribaudo