Across the Zodiac: The Story of a Wrecked Record details the creation and use of apergy, a form of anti-gravitational energy, and details a flight to Mars in 1830. The planet is inhabited by diminutive beings; they are convinced that life does not exist elsewhere than on their world, and refuse to believe that the unnamed narrator is actually from Earth. (They think he is an unusually tall Martian from some remote place on their planet.)

Percy Greg (1836-1889) was an English writer. He wrote about politics, but his views were violently reactionary. His novel Across the Zodiac is an early science fiction novel, said to be the progenitor of the sword-and-planet genre. For that novel, Greg created what may have been the first artistic language that was described with linguistic and grammatical terminology.