We can use as proof the pendulum that proving the rotation of the earth, it's called Foucault pendulum, if earth is rotating, it must be spherical, I am not insist tho, better just google it. Ok?
Dartmouth Professor Discusses Foucault's Pendulum - YouTube
https://www.youtube.com/watch?v=aMxLVDuf4VYRead the comments, lol.
Flatards can't even understand one of the simplest experiments that anyone can perform to prove earth's rotation, what a surprise. I got cancer from the comments, thanks.