i don't know if anyone else has mentioned this, and i don't know if it has been commented on this post, but ever since around 2000 BC it has been widely accepted by anyone who truely cared to think about it that the world is, infact, a globe.
it wasn't until farely recently (as in when America came to be) that they were trying to romantise Columbus by saying that everyone thought the world was flat but he thought it was round.
The actual problem was that they all thought that it was not possible to transverse the atlantic because of a mixture of: Bad weather, heavy seas, and Monsters (ie ships never reapearing)