X: X Marks the Spot
X marks the spot, though the spot is arbitrary: the prompt called for looking at one’s bookshelf and, starting at the upper left, counting to the 27th book. I’m pretty sure this is because Jamie was 27 when she wrote her original post and not for any other arcane numerological reasons. Being 27 myself, I followed suit on each of my bookcases.
This seems especially arbitrary because I need to reorganize my shelves.
If only the 27th book on at least one of my shelves were Munster’s Cosmographia Universalis, or something along the lines of the Musgrave Ritual! Then there would be some point to marking the spot.