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Benham's Disk
When the disk is spun, the colors you see are illusions. This effect was popularized in 1894 by toymaker C. E. Benham, who called his spinning disk an “artificial spectrum top."
Bird in a Cage
Stare at a bird’s eye for 30 seconds, then look into the empty cage. You’ll see a ghostly bird—of a very different color—inside the cage
Cheshire Cat
Make your partner's face disappear, leaving only a smile.
Flourish (Bloom)
This 3-D sculpture is animated when spun under a strobe light. The bloom’s animation effect is achieved by progressive rotations of the golden ratio, phi (ϕ), the same ratio that nature employs to generate the spiral patterns we see in pinecones and sunflowers.
Time to Think
At this exhibit, you can test your reaction time in three different scenarios—each requiring an increasing amount of thought. In the process, you can actually measure the time it takes your brain to accomplish the extra work of making a (fast) decision.
Where: Crossroads: Getting Started
