> Did the builders knew the earth was round?
Yes. This has been known since ancient greek times, and Aristotle calculated the size reasonably well. Maybe not every labourer knew or cared but the architects almost certainly did
Yes. This has been known since ancient greek times, and Aristotle calculated the size reasonably well. Maybe not every labourer knew or cared but the architects almost certainly did
Even knowing the earth is round, if I were going to put things in a "straight line" geographically, I'd do it with the reference most people would actually use and see: a 2D map.
The expert used spherical mathematics. This was quite widespread knowledge required to build proper sun dials and in the Late Medieval period for long distance navigation. Some were able to use analog computers, called "armillary spheres", for the calculations, which were known since Antiquity.[1]
Locations are chosen for the sake of the people who are expected to come to them.
I'll try to look up an exact quote later. But the gist of several passages was that there was an elite or expert community- obviously, or nobody would have been designing buildings like this!
Let's assume for the sake of this discussion that the 7 sites are deliberately aligned by somebody. They would presumably be a powerful elite, and would be doing it to impress other powerful elites.
"Die Entdeckung der mittelalterlichen Stadtplanung" (2004): https://www.youtube.com/watch?v=-ZzEzhIGnwM
"Mittelalterliche Baukunst – Schönheit ist planbar" (2009) https://www.youtube.com/watch?v=MQcKOkbagDc
Both documentaries are in German, but are well worth watching, even if the automatic English subtitles are sometimes a little inaccurate.
These places are old. Skellig Michael goes back past 823AD, Mont-Saint-Michel is about the same sort of age, and the Sanctuary of Monte Sant'Angelo goes back to 490AD(ish). San Michele Arcangelo is on top of a pre-Christian pagan temple. Stella Maris is on an Old Testament Biblical site. None of them is less than a thousand years old.
The bar for finding a map that happens to align, and then explaining how it was made, is not a low one.
There is a projection that might fit, though: Plate Carrée is definitely old enough, and a brief visual sanity check doesn't make it look totally off.
Virtually everything in church design is meant to communicate truths of the faith to illiterate laypeople. That's part of why pictures feature so prominently. They're telling stories to people who can't read. The sense of space, and the drawing of the attention upward, they're also communicating to people on purpose.
If the argument is that the sites were not intentionally built in a line, that it just happened this way, that there just happen to be seven prominent hills with churches built on them that refer to St. Michael (or 6 and Mt. Carmel, which is associated with him in another way), I guess that's a different conversation, but I thought the idea here was that these were lined up somehow on purpose, at least for the latter built ones, and were intentionally built to be "in a line" by some meaning of the term.
What I'd want to know is how old the story of St Michael's Sword actually is. Not the churches, but what's the earliest reference to them being in a line. My bet is that it's well after Mercator, and probably safely after the 18th century, when chunks of Europe got geodetic surveys done.
Mercator exists because it’s easy to navigate with. It’s easy to navigate with because it preserves bearings. Lines of constant bearing are, when you’re navigating on the ground, much more meaningfully ‘straight’ than geodesics.
‘Keep heading North West’ sounds like a pretty straight line.
Eratosthenes.
https://en.wikipedia.org/wiki/Earth%27s_circumference#Eratos... https://en.wikipedia.org/wiki/Eratosthenes#Measurement_of_Ea...