Complex sentence: Edgar Allan Poe's 1839 short story "The Conversation of Eiros and Charmion" has two souls in the afterlife discussing the destruction of the world by a comet that removed nitrogen from earth's atmosphere; this left only oxygen, resulting in a worldwide inferno.
Split into simpler sentences: Edgar Allan Poe's 1839 short story "The Conversation of Eiros and Charmion" follows the conversation between two souls in the afterlife as they discuss the destruction of the world. The destruction was brought about by a comet that removed nitrogen from earth's atmosphere; this left only oxygen and resulted in a worldwide inferno.