What is happening in the first four lines of the story "The Pit and the Pendulum"? Describe the dramatic tension that this opening creates.

In the first four lines of "The Pit and the Pendulum," the narrator indicates his wavering consciousness. Further, the narrator seems to also exhibit a character that is hallucinatory; so, there is dramatic tension created in the narrative because the lines between reality and what is in the mind of the narrator become blurred. 

These first lines of Poe's story set the moribund and horrific tone for the narrative. There is also a sense of utter despair with the phrase "sick unto death with that long agony." And, this despair is accompanied by the hallucinatory character of the narrator--

I felt that my senses were leaving me....the sound of the inquisitorial voices seemed merged in one dreamy indeterminate hum--

all of which suggest the narrator's unstable consciousness. Certainly, he is isolated and in a desperate situation. But, the reader must perceive this situation through the vortex of the narrator's agonized mind.