In 1894, toymaker Mr. C.E. Benham discovered that a spinning disk with a particular pattern of black and white marks could cause people to see colors. Mr. Benham called his disk an "Artificial Spectrum Top" and sold it through Messrs. Newton and Co. Benham's Top (or Benham's Disk) has puzzled scientists for over 100 years.
ACTIVITY: Benham's Top
Online Resources
Simulation: http://www.biyee.net/color-science/benham-top/
