to have no mass. In the story, it is indeed a vaporous comet that strikes the Earth depleting the atmosphere of nitrogen. Olson and Ford also suggest possible sources of Poe's knowledge of both comets: Elijah Hinsdale Burritt's The Geography of the Heavens and John Herschel's 1835 A Treatise on Astronomy. Another astronomy study-book for young people, James Ferguson's 1819 Edition of An Easy Introduction to Astronomy for Young Gentlemen and Ladies, might have been available to a young Poe. Poe's foster father John Allan provided Poe with a telescope as a teenager, and the researchers speculate Ferguson's book may have also been a gift. The book includes a passage of dialogue between a brother and sister (Neander and Eudosia) discussing the possibility of a comet setting the world on fire and then dismissing that possibility because of the tenuous nature of comets. Eiros and Charmion are named after Cleopatra's attendants, Iras and Charmion (or Charmian); they are mentioned by the Greek historian Plutarch in his biography of Mark Antony (in his work Parallel Lives); they appear in William Shakespeare's play Antony and Cleopatra, and John Dryden's play about Antony and Cleopatra, All for Love. References External links Publication history at the Edgar Allan Poe Society 1839 short stories Fiction about comets Short stories by Edgar Allan Poe Science fiction short stories Impact events in fiction Works originally published in Burton's Gentleman's Magazine Apocalyptic fiction