side tunnel that led
toward one of the main robot tunnels. When they finally came to a
tunnel labeled _Robots and Passengers Only_, Ardan rolled into it and
revved his wheels up to high speed, shooting down the tunnelway at a
much higher velocity than Dodeth could possibly have run.

The tunnelway was crowded with passenger-carrying robots, and with
robots alone, carrying out orders from their masters. But there was no
danger; no robot could harm any of Dodeth's race, nor could any robot
stand idly by while someone was harmed. Even in the most crowded of
conditions, every robot in the area had one thing foremost in his
mind: the safety of every human within sight or hearing.

Dodeth ignored the traffic altogether. He had other things to think
about, and he knew--without even bothering to consider it--that Ardan
could be relied upon to take care of everything. Even if it cost him
his own pseudolife, Ardan would do everything in his power to preserve
the safety and health of his passenger. Once in a while, in unusual
circumstances, a robot would even disobey orders to save a life, for
obedience was strictly secondary to the sanctity of human life, just
as the robot's desire to preserve his own pseudoliving existence was
outranked by the desire to obey.

Dodeth thought about his job, but he carefully kept his mind off the
new beasts. He knew that fussing in his mind over them wouldn't do him
any good until he had more to work with--things which only his
parabrother, Yerdeth, could supply him. Besides, there was the
problem of what to do about the hurkle breeding sites, which were
being encroached upon by the quiggies. Some of the swamps on the
surface, especially those that approached the Hot Belts, were being
dried out and filled with dust, which decreased the area where the
hurkle could lay its eggs, but increased the nesting sites for
quiggies.

That, of course, was a yearly cycle, in general. As the Blue Sun moved
from one side to the other, and the winds shifted accordingly, the
swamps near the Twilight Border would dry out or fill up accordingly.
But this year the eastern swamps weren't filling up as they should,
and some precautionary measures would have to be taken to prevent too
great a shift in the hurkle-quiggie balance.

Then there was the compensating migratory shift of the Hotland
beasts--those which lived in the areas where the slanting rays of the
Blue Sun could actually touch them, and which could n