"And then I fell suddenly calm, and lay smiling at the glittering death, as a child at some rare bauble...."See in text(The Pit and the Pendulum)
This simile intimates the narrator’s thought process: at first petrified of his impending death, he now accepts it like a child admiring a “bauble,” or a trinket. The pendulum, which moments ago resembled a menacing, ominous “scimitar,” now transforms before the narrator’s eyes into a harmless knickknack.
"I now observed—with what horror it is needless to say—that its nether extremity was formed of a crescent of glittering steel, about a foot in length from horn to horn; the horns upward, and the under edge evidently as keen as that of a razor...."See in text(The Pit and the Pendulum)
The pendulum—described in menacing metaphorical language in phrases like “glittering steel,” “horns upward,” and “keen as that of a razor”—represents the inexorable passage of time. Shaped like Father Time’s scythe, the rhythm of the pendulum mimics the narrator’s heartbeat and brings him closer and closer to death with each passing swing.
"A deep sleep fell upon me—a sleep like that of death...."See in text(The Pit and the Pendulum)
Through repetitive language and simile, the narrator once again describes how he falls into a deep slumber. By comparing his sleep to “that of death,” the narrator demonstrates how weak he has become.
"like a rich musical note,..."See in text(The Pit and the Pendulum)
The narrator, so petrified of the situation he finds himself in, wishes desperately for death. Using simile, the narrator claims that the prospect of “sweet rest” appeals to him as a “rich musical note.” He wishes for death, because to him, it is sweeter, gentler, and more welcoming than of the torture he imagines he will face.
"as if I had touched the wire of a galvanic battery..."See in text(The Pit and the Pendulum)
A “galvanic battery” is a device consisting of several cells that produces electricity. The narrator undergoes a sudden change—he jolts awake—which he likens to feeling like he touched the raw end of a battery. This simile conjures a sensation of electricity running through and shocking the body.