What are Edgar Allan Poe's stylistic elements?
The stylistic elements that Poe uses in his stories that really characterize him.
In addition to his place among "Gothic" authors, Edgar Allan Poe is known as the grandfather of horror in American Literature, because he was the first to employ many of his signature style elements in his work. You could probably categorize Poe's writing under any of the basic elements of Gothic literature (setting, tone, presence of the supernatural or evil, etc), but I think there are three that shine through in his works the strongest.
First, I would include point-of-view. Many of Poe's stories and poems are written in 1st person point-of-view and the narrator is nearly always untrustworthy. In this way, Poe's stories come across as scary/mysterious in themselves, but additionally eerie due to a creepy narrator. "Tell Tale Heart" is only one of the many stories that most of the intensity and fear is created by a narrator who may or may not be in his right mind.
Poe is also known for creating compelling atmosphere in all of his stories. As a literary element, atmosphere is the combination of a specific setting and tone. Poe often creates an eerie or spooky atmosphere through setting stories in remote places (and old houses or cabins) and adding to the already spooky place bad weather and illness. Combined, these elements are common to many of his stories and make the stories uniformly dark and mysterious. "The Fall of the House of Usher" and "The Raven" are two easy examples of atmosphere as a predominant literary element.
Finally, one of Poe's greatest achievements was his ability to create really twisted characters. In addition to untrustworthy narrators in many stories, Poe had an affinity for adding mental or physical diseases and ailments to many of his stories. As the first author in America to really play off this, you can see where the technique has been expanded into much of our modern day horror. There is simply something innately scary about things humans cannot control and do not fully understand, especially when it is clear they actually exist. Mental disorders in characters is so common to Poe that those who have read enough of his works tend automatically not to trust the sanity of any of his characters. Think of Roderick and Madeline Usher, the narrator in "The Tell Tale Heart," or the prisoner in "The Pit and the Pendulum."
Edgar Allan Poe uses many different elements of style in his writing. Most commonly, he uses first person narration. You can find first person narration in many of his works, including "The Raven", "The Pit and the Pendulum", "The Fall Of the House Of Usher", and more.
Poe also uses hyphens to indicate agitation or fear in his narrator. Generally, when many hyphens appear in a paragraph or stanza, the narrator is in an altered mental state of some kind.
Poe also uses sound frequently, especially in his poetry, especially devices such rhyme and alliteration. There are examples of both internal and external rhyme in "The Raven" and "Annabel Lee". One of his most famous lines "Once upon a midnight dreary, while I pondered weak and weary" is an example of internal rhyme. Alliteration is also used in "The Raven" especially in the line, "And the silken, sad, uncertain rustling of each purple curtain" the alliteration serves to convey the mood of the poem.
Poe's literary elements are certainly not limited to these, but first person narration, hyphen use, rhyme, and alliteration are some good places to start.