A Martian Odyssey

Early in the 21st century, the Ares makes the first landing on Mars, in the Mare Cimmerium. A week later, Dick Jarvis, the ship's American chemist, sets out to photograph the landscape. Eight hundred miles out, the engine on Jarvis' rocket gives out, and he crash-lands. He starts walking back to the Ares. Just after crossing into the Mare Chronium, Jarvis sees a tentacled creature attacking a large birdlike creature. He notices that the latter has a bag around its neck, and recognizing it as an intelligent being, rescues it. The creature refers to itself as Tweel. Tweel accompanies Jarvis on his journey, during which it manages to pick up some English, while Jarvis is unable to make any sense of Tweel's language. At first, Tweel travels in tremendous, city-block-long leaps, but then walks alongside Jarvis.