Quote 4
A moment more and I had fettered him to the granite. (71)
Fortunato has completely lost his freedom at this point. But he’s still unaware of the fact. He can’t believe Montresor would do this to him. He’s still holding out hope for the Amontillado.
Quote 5
For the half of a century no mortal has disturbed them. (89)
Meaning, the bones covering Fortunato’s casket of despair. Montresor’s crime has gone undetected for fifty years. He’s bragging that he got away free. Or he’s confessing that he killed a man. Or possibly it’s a combination of both.
Quote 6
THE thousand injuries of Fortunato I had borne as I best could, but when he ventured upon insult, I vowed revenge. (1)
It’s important to notice that Montresor wants revenge, not for his injuries, but for the insult. The word “ventured” is also interesting. It literally means “to undertake an action with knowledge that there is risk involved.” This quote suggests that Montresor thinks that Fortunato knew what he was risking, but chose to insult or betray him anyway.