Image Number 2 for United States Patent #4394016.
A game having a first cylinder with an inner helical path and a second cylinder concentric with the first cylinder having a second helical path continuous with the first path. In one embodiment the paths are grooves in the cylinder walls. A ball having a smaller diameter than the groove is attempted to be rolled in the groove using centrifugal force. A hollow handle is attached at the bottom of the cylinder to catch the ball should it fall. In another embodiment the paths are tracks over which passenger vehicles move. The tracks are housed in enlarged cylinders driven by a parabolic lever.