Fane chuckled. "Always the smart boy, eh, Mills? Better keep it up. Because Mercury's a crazy place. It's the planet closest to the sun. But it forgot to turn on its axis ages ago. So the dark side is colder than Pluto must be. But on the solar side your space-boots can slosh into wetness that you might believe is water. Umhm-m. Only it turns out to be a puddle of molten lead. "Hell, you guys have always known stuff like that. So why repeat myself? When there are interesting circumstances? A push-button war fifty million years old that got put into cold storage, for instance. Dead storage. But maybe not quite dead. I wouldn't know, for sure. How about getting mixed up with that?" Some strange jubilance seemed to possess Fane. The retard-jets of the _Sun Child_ thundered to check vast speed. Conversation died as, from the zero of free-fall, weight rose to five gravities, pushing the corners of men's mouths back toward their ears. Still, in spite of the strains in his own stocky, muscular body, Rick Mills kept an eye cocked at the long, sinewy shape that was Fane, prone on taut canvas across the aisle. Fane's grimace remained reckless. With the mystery of Mercury at hand, Rick was like his companions. He thought some of home. Minnesota. His folks. Anne Munson. Anne who was on Mars, at the Survey Service School. They could use girls for certain less rugged jobs, Rick thought of her picture in his pocket. Honeydew hair. Cool, pleasant eyes. And under her smile her scribbled, half-kidding challenge: "_Find us a world, Rick!_" Well, it would never be hellish Mercury. No place for a girl. * * * * * Rick also thought that he would have liked to like Fane if he could. Now didn't seem the right time. His veiled bragging and shows of insolence had begun to exceed the limit, even for rough men. And there were too many questions in Rick's mind now. Was Fane struggling to keep some inner elation from showing too much? What did he want from life? Wealth, maybe? Did he have a Mercurian secret that led toward what he wished to accomplish? Rick's cold feeling found its chief source in the Martell Expedition to Mercury of a year ago. Just Martell, Jacobs, and Fane--the pilot and mechanic--in a small, long-range rocket ship. On his return, Fane of course couldn't be evasive in his written report to the Interplanetary Colonial Board. It had been published. Rick could remember parts of it almost word for word: "... We had gone a hundred miles into the dark hemisphere with the tractor. Martell wandered off alone. Jacobs and I found him with a hole in the back of his oxygen helmet. Falling backward onto a sharp rock could have done it. The hole let the air out of his space suit, and the cold in.... "Jacobs ended up just about the same, two Earth weeks later. Except that it was on the hot, sunward hemisphere...."