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.)