On card number 13, Frankenstein, it is revealed that Mary Shelly is a Janus, and it is mentioned that she specifically put in the line "dreams of forgotten alchemists" as a reference to Gideon Cahill. In my version of Frakenstein which is not a retelling, that line is on page 36. If you remove all of the intruductions by other authors and the more recent one by the author, you are left with the story, the two-page original preface, and the title page. Together, 36+2+1=39, which means that technically that quote is on page 39! If Shelly wasn't a Cahill, this would be a very odd coincidence.