what three coincidences happen while the narrator is reading from the book Mad Trist by Sir Launcelot Canning to Usher?

- There is a strange echo sound in the house, similar to the story when Ethelred's attempts to enter the hermit's dwelling.

-When the dragon in the story is struck by Ethelred, the sound it makes is similar to another sound in the house. "harsh, protracted, and most unusual screaming or grating sound."

-A shield falls to the ground in the story and in the house they hear, "distinct, hollow metallic, and clangorous, yet apparently muffled reverberation."