The Fall of the House of Usher
How we cite our quotes:
An air of stern, deep, and irredeemable gloom hung over and pervaded all. (7)
This air of gloom is akin to the actual fog that surrounds the mansion.
To an anomalous species of terror I found him a bounden slave. "I shall perish," said he, "I must perish in this deplorable folly. Thus, thus, and not otherwise, shall I be lost. I dread the events of the future, not in themselves, but in their results. […] I have, indeed, no abhorrence of danger, except in its absolute effect--in terror. In this unnerved—in this pitiable condition--I feel that the period will sooner or later arrive when I must abandon life and reason together, in some struggle with the grim phantasm, FEAR." (11)
Roderick isn’t afraid of death or pain; he is afraid of fear. And as he predicts, this is precisely what he dies of, when Madeline comes back from her tomb and scares him to death.
He was enchained by certain superstitious impressions in regard to the dwelling which he tenanted, and whence, for many years, he had never ventured forth--in regard to an influence whose supposititious force was conveyed in terms too shadowy here to be re-stated (12)
Over and over again, the narrator reiterates the impossibility of his accurately conveying the events of this episode on the written page. The story is too spooky, too other-worldly, too scary for him to get across in full.