Tesla was a proponent of several Gravity Theories, most of which are still used today, Flatnon. You're not even trying.
Gravity would still have to be true even if the earth was flat, Flatnon.
You can prove gravity exists by jumping. If you return to the ground, Gravity exists. If you keep going up, up, and up, Gravity doesn't exist.
The only difference the earth being a globe or flat would make to gravity is HOW it works, not that it works.
Even the Bible says that the Earth is round. The oft quoted 'four corners' passage not withstanding - if taken literally it's still only referring to the magnetic corners (contrasted with the magnetic poles).
I'm not saying you do. I'm saying Flatnon's argument is entirely invalid from ALL angles, even the claimed biblical one.