[Anaraxes]

From the map, those lozenges seem to cover 15-degree squares of lat/long. They're lozenge-shaped because of the funky map projection.

Puerto Rico to Roanoke is 18 degrees of latitude, so it's not that far off. It would easily fit in a lozenge not aligned with lat/long lines if you rotated it. But if it also has to include the Yucatan, it gets harder, mostly because of the east-west distance. (Bermuda 32.3 N 67.8 W; Yucatan 18.8 N 89 W; Roanoke 35.9 N 75.7 W)

It would be a bizarre coincidence for the Vortices to happen to coincide with pentaphilic round numbers in an arbitrary coordinate system. So clearly that's not arbitrary. The Babylonians were on to something fundamental with their base 60 math, and equally it is not just an arbitrary or self-interested choice of Greenwich by overweening Englishmen that that longitude is the zero point. (It runs through Algeria and Mali, for instance; Timbuktu is 3 W. But then, scientists that have forgotten the real purpose of the lines have moved them a bit from their original placement.)