Boat Speed?

[skip.knox]

WRT 3, medieval people knew the world was round. At least the ones who were in a position to need to care. The flat earth thing is a post-medieval invention.

WRT 1, it reminded me of Seebuecher (sea books). These were instruction guides for navigators in the North Sea and the Baltic. They weren't maps or charts, they were more like narratives. They gave detailed descriptions of landmarks of all sorts, including islands and soundings. It was rather like instead of a map you told your friend: from your house turn right and drive until you see the gas station with the green sign, then turn right. Etc.

Sea books were prized possessions, closely guarded, much like the portolani used by sailors in the Mediterranean. It's one thing to say to sail along the coast, but it's quite another to do so *without crashing*. Captains and navigators had the super-secret knowledge of how to do this.

Sailing out of sight of land could be done, though. Sailors crossed the eastern Mediterranean regularly, sailing for about three days on open sea, if the winds were right. That's a far cry from sailing the Atlantic, of course, but even that was done by the Norsemen. Scary stuff.

 

[wordwalker]

WRT 3, medieval people knew the world was round. At least the ones who were in a position to need to care. The flat earth thing is a post-medieval invention.

Quite right. The idea that Columbus was the only one to see the earth as round was a myth Washington Irving added to history. What really happened shows a bit of what sailing like this can involve:

To the rest professional and educated world, the planet was simply too big for anyone to sail from Europe to Asia without starving on the way. Columbus thought it was smaller-- because he'd made an error in his math.

And of course the only way to find out there were continents there was to be that wrong, or otherwise be fool enough to make what seemed like a suicide mission. (That or to be a Viking starting all the way out in Greenland, but...)