The most obvious method that Poe is using to create an unsettling atmosphere is through his sentence structures. His use of dashes, which are not common, helps to create a frightening atmosphere. The dashes help the reader to picture the movement of the pendulum, which is getting steadily closer. This image is extremely unsettling. In addition to his use of sentence structures, Poe chooses words carefully, words that create sensory images. Words like "crept," "shriek," "stealthy," and "alternately laughed and howled" appeal to the reader's senses and create the frightening atmosphere that pervades the passage.
