What I liked about it was the detailed method used by Legrand to break the pirate's code and then interpret it to locate the booty.
I enjoyed that as well. I think Poe's writing of Legrand's explanation of how to break the cypher was well done because it explained it reasonably and simply without being a dry synopsis of how to break a code. I also enjoyed that Legrand knew his friend thought he was somewhat out of his head so he screwed with him a little. ;)
Jackie