Ruins And Desert

Satan's World, XX.

Adzel to van Rijn:

"'...I cannot offhand see how a society few in numbers could build - could even design - the vast, sophisticated production plant that Dathyna evidently possesses.'" (p. 539)

But Thea has already given van Rijn some massive clues back in Chapter XIX when she reminisced:

one of her master's sons took her exploring even though they remained within a single large and old building;

leaving the household, they entered ruins where they found machinery that had not rusted much;

from a high tower, they looked across a seemingly endless desert.

Maybe the desert is natural or maybe it results from a catastrophe but clearly the population has shrunk and its remnant camps in the ruins of a civilization.