To Do And Notice  Stare at the center of the disk for about 15
seconds. Stare at the palm of your hand. Notice that your palm
seems to be turning in the opposite direction from the way you
turned the wheel.   What's Going On?  When you stare at a moving
pattern, your eyes and brain get used to seeing movement. When
you look at something that's standing still, your eyes see
movement in the opposite direction. The common name for this
illusion is the waterfall effect. If you stare at a waterfall
for some time and then look at the nearby rocks, the rocks may
look like they are moving upward.   What else can I do?  The
Depth Spinner exhibit also demonstrates a similar phenomenon
What if the animation is playing too slow to see the effect?
Results of this experiment may vary depending on your computer's
processing speed, the amount of RAM allocated to your browser
and the colordepth your monitor is set to.   You can increase
animation performance by:   • Switching your monitor's color
depth to 256 colors   • Clo