Irony in the Cask of Amontillado

Fortunato, arguing that Luchesi is unskilled in the knowledge of fine wines, demands that he must come and taste the Amontillado for himself. Henceforth, Fortunato, intoxicated and dressed in jester's attire, is played the fool. .
             Fortunato belongs to a secretive group known as the Freemasons, whereas the narrator, by his description of the events, is positively not a fellow member. This is evident when Fortunato is given a bottle of De Grave, symbolic of his fate: "He laughed and threw the bottle upwards with a gesticulation I did not understand. I looked at him in surprise. He repeated the movement - a grotesque one" (Bedford, 465), the gesture being a secret code of the Freemasons. When Montresor is asked to display a sign of his membership he is unable to comply in the proper manner. Instead, he presented a trowel taken from beneath his cloak. Fortunato, believing the gesture to be a joke, assumes that Montresor is indeed a member. The irony here is that Fortunato, a Freemason, will eventually be entombed behind a wall built with the use of this trowel. Montresor will stifle the Freemason with masonry. .
             Furthermore, Montresor appears to be especially concerned about Fortunato's health. The catacombs are damp and chilly and Fortunato is ill with a cough. Throughout their journey through the catacombs, Montresor argues that it is not in Fortunato's best health to follow him to the Amontillado. As he attempts to convince him to turn back from the unhealthy surroundings, Fortunato responds, "I shall not die of a cough.", "True - true." Montresor replies (Bedford, 465) Fortunato is unaware that Montresor would rather see him die by his intentions rather than a cough. .
             As they travel further into the catacombs Fortunato drinks from a bottle of Medoc and toasts to "the buried that repose around us" (Bedford 465), Montresor replies with a toast to his victim's long life. It is quite comical considering Montresor is about to kill Fortunato even though he just toasted to his long life, and Fortunato will soon join the dead that he toasted to.