PLEASE PRESS F11 KEY FOR FULL SCREEN VIEW OF THIS TOUR


Information presented in the most useful format to the navigator can occasionally be misleading.
If your mind functions
optimally you will find it impossible to believe that squares marked
"A" and "B" are exactly the same shade.
To convince yourself that this is indeed so you can print the page and overlap the squares.
This remarkable illusion was created by Prof. Edward H Adelson