The narrative technique that bears the most tension in the readings of "The Pit and the Pendulum" by Edgar Allen Poe (1843) and "After Twenty Years" by O. Henry (1906) is the setting.
Thus, Poe's "The Pit and the Pendulum" concentrated on scenes where the unreliable narrator was tried and sentenced to death, just as O. Henry's "After Twenty Years" dwelt on the scene where Bob was cut by the long hand of justice for a crime through his long-time friend, Jimmy.
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