Edgar Rice Burroughs 
Princess of Mars [PDF ebook] 

A Princess of Mars is the first in Edgar Rice Burroughs’ Barsoom series. This science fiction planetary romance, packed full of dangerous feats and swordplay, is set on a dying Mars. It went on to inspire some of the great imaginations, among them Arthur C. Clarke, Ray Bradbury and Carl Sagan. Civil War veteran John Carter is unexpectedly transported to Barsoom, the planet we call Mars, and finds with the weaker gravity that he has super-human strength. In combat he finds respect and belonging with the Tharks, an aggressive race of green four-armed nomads. But when the Tharks capture the human-like Dejah Thoris, Carter feels the need to help this beautiful princess of Mars.