|"Pillar of Cloud, Pillar of Fire"|
|Series||Agent of Byzantium|
|Publication date||mid-December, 1989|
|Preceded by||"Strange Eruptions"|
|Followed by||"Unholy Trinity"|
"Pillar of Cloud, Pillar of Fire" a.k.a. "Etos Kosmou 6818" is an alternate history short story published in Isaac Asimov's Science Fiction Magazine in the mid-December 1989 issue. It was reprinted in the Harry Turtledove collection Departures in 1993 and in the revised 1994 edition of Agent of Byzantium.
Although set in the same timeline as the short story "Departures", it takes place some 700 year later. It is set in and around Alexandria, Egypt, in 1309 AD, and concerns the attempts by the magistrianos Basil Argyros to restart the stalled re-construction of the pharos or lighthouse which had been destroyed in an earthquake several generations earlier.
Much of the trouble is concerned with the Alexandrian masons banding together and refusing to go back to work unless given better and safer working conditions, such united stopping of work being called anakhoresis. Argyros, who had never before heard of such strange behavior by craftsmen, attributes it to the notorious strangeness of Egyptian society. Still, he must find ways of dealing with it - and especially, with the wife of one of the leaders of the anakhoresis.