A double pendulum with a floppy joint. That is more or less
   accurate view, I believe, of the inside of most imperceivable
   things. Not balls.
   [vine id = "Mud5g60LtZr"]
   A double pendulum with a floppy joint. That is more or less
   accurate view, I believe, of the inside of most imperceivable
   things. Not balls.