That doesn't make much sense to me. The world is really big so how would you know you were flying/sailing "around" it when you could just be traveling in a circle.

Flying in a plane or sailing in a boat from destination to destination is not solid proof that Earth is globe.

Compasses point North on both style of Earth.

I realize I said "magnets point North" in the first message. I meant to say compasses point North. And since North would be in the center of the map, traveling east/west would not proof Earth to be flat or a globe.