Jack had to ponder this ænigma for a moment. The happiest possible interpretation was that the King was speaking of Eliza, and that she was waiting for Jack on London Bridge. But given the general turn of recent events, this did not seem likely; the Jack-Eliza matter would definitely be classed as a "broil," not worth bringing up in conversation. Thinking of London Bridge reminded him of the water-pumps there at the northern end, which banged away like giants’ hearts; this, then, reminded him of the Tower, and finally he got it.