The city of Jahilia is built entirely of sand, its structures formed of the desert whence it rises. It is a sight to wonder at: walled, four-gated, the whole of it a miracle worked by its citizens, who have learned the trick of transforming the fine white dune-sand of those forsaken parts, - the very stuff of inconstancy, - the quintessence of unsettlement, shifting, treachery, lack-of-form, - and have turned it, by alchemy, into the fabric of their newly invented permanence.