chunk: Fox, Ashe, and Murdock serve as roving sentries in the area around the smaller globeship as technicians build a time transfer cage around it. The ash from a volcanic explosion and a stampede of mammoths drive the three men into the ship with Case Renfry, an electronics technician, on the day the transfer is to be made. An earthquake triggers the transfer, bringing the ship into the present, and then the ship’s preset autopilot, jolted into action, takes the ship into space.
  After carrying the men through hyperspace, the ship lands on a planet where faltering robots refuel the ship. Another leap through hyperspace brings the ship to the second planet of an alien solar system. The ship lands in a desert, sits for a couple of days, and then blasts off on a course that takes it to the system’s Earth-like third planet. Upon landing the ship indicates that the voyage has ended by ejecting a small discus from its autopilot.