[tz] Flat-earthers and time zones

[Paul Eggert]

Patrice Scattolin wrote:
> A better question to ask is when circular earth became dominant belief.

If by "dominant" you mean "known by educated people in the West", I would say 
that this occurred well before 200 B.C. And by "dominant" I mean really 
dominant: there was no real controversy about whether the earth was flat, as 
virtually every educated person on record wrote that it was round. (The idea 
that the ancients thought the world flat is a modern myth.)

By the third century B.C. people in the West realized that clock settings varied 
by longitude. Perhaps some ancient Roman or Greek geographer even developed a 
precursor to tzdb, though I don't know of any such effort that survived.

For more, please see:

https://en.wikipedia.org/wiki/Myth_of_the_flat_Earth