Great Book of Optical Illusions

The puzzles in this book are optical illusions. They are straight lines and perfect circles and two-way tricks and other shapes and drawings that keep you from seeing what's there-or make you see something that isn't there at all.

Here are pictures that seem to move, images that mysteriously disappear and reappear, others that seem to be there but aren't–plus over 100 more amazing illusions. "Entertaining collection…I applaud the number and variety of images presented."– "Science Books & Films, Best Children's Science Booklist, 1988