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Dalla was looking about her in surprised delight; for her, the vacation had already begun.  He was glad; for a while, he had been afraid that she would be unhappy about it.  He guided her through the crowd to the desk, spoke for a while to one of the human attendants, and found out which was their conveyer.  It was a fixed-destination shuttler, operative only between Home Time Line and Police Terminal, from which most of the Paratime Police operations were routed.  He put Dall in through the sliding door, followed, and closed it behind him, locking it.  Then, before he closed the starting switch, he drew a pistollike weapon and checked it.

In theory, the Ghaldron-Hesthor paratemporal transposition field was uninfluenced by material objects outside it.  In practice, however, such objects occasionally intruded, and sometimes they were alive and hostile.  The last time he had been in this conveyer room, he had seen a quartet of returning officers emerge from a conveyer dome dragging a dead lion by the tail.  The sigma-ray needler, which he carried, was the only weapon which could be used, under the circumstances.  It had no effect whatever on any material structure and could be used inside an activated conveyer without deranging the conductor-mesh, as, say, a bullet or the vibration of an ultrasonic paralyzer would do, and it was instantly fatal to anything having a central nervous system.  It was a good weapon to use outtime for that reason, also; even on the most civilized time-line, the most elaborate autopsy would reveal no specific cause of death.

“What’s the Esaron Sector like?” Dalla asked, as the conveyer dome around them coruscated with shifting light and vanished.

“Third Level; probability of abortive attempt to colonize this planet from Mars about a hundred thousand years ago,” he said.  “A few survivors—­a shipload or so—­were left to shift for themselves while the parent civilization on Mars died out.  They lost all vestiges of their original Martian culture, even memory of their extraterrestrial origin.  About fifteen hundred to two thousand years ago, a reasonably high electrochemical civilization developed and they began working with nuclear energy and developed reaction-drive spaceships.  But they’d concentrated so on the inorganic sciences, and so far neglected the bio-sciences, that when they launched their first ship for Venus they hadn’t yet developed a germ theory of disease.”

“What happened when they ran into the green-vomit fever?” Dalla asked.

“About what you could expect.  The first—­and only—­ship to return brought it back to Terra.  Of course, nobody knew what it was, and before the epidemic ended, it had almost depopulated this planet.  Since the survivors knew nothing about germs, they blamed it on the anger of the gods—­the old story of recourse to supernaturalism in the absence of a known explanation—­and a fanatically anti-scientific cult got control.  Of course,