Tyrion (and servants), Jon, and Benjen head north for the Wall, running into another member of the Night's Watch, a recruiter named Yoren.
Yoren has two rapists who are going to join the Night's Watch, which bothers Jon: he had imagined the Night's Watch was still noble, but Tyrion points out that it's mostly made up of criminals. Tyrion is impressed when Jon accepts that "hard truth."
Tyrion also reads about dragons, so we get some history here: apparently, the Targaryens once had very powerful dragons (which is how they conquered Westeros), but over the years, the dragons became weak and sickly and extinct. Kind of a bummer.