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What happens if you shine light through a glass ball?
Say you've got a glass ball and you put a flashlight right up against it and hit the switch. What happens? Does the light come out in a beam on the other side or does the ball glow?
There should be a very faint beam, and the ball will glow a lot depending on what kind of flashlight. Mine was somewhat blinding to look at, maybe because I was using a quite strong light...
Talented Glass Ball Contact Juggler