Show SEEMING CHANGES IN COLORS Why Long Exposure of the Retina to the tho Action of Red Rays Creates an Optical Illusion It Is well known that when a ray of white light Is analyzed as by a prism It Is found to be composed of seven colors the Ule so-called so colors of the spectrum spectrum red red orange yellow green blue Indigo and violet violet and and that when the colors of the spectrum are recombined white light reappears If however we eliminate the ree red rn rays 8 and then recombIne the remaining six colors we obtain the so-called so complementary complementary complementary com com- color of the red namely green If we eliminate the green rays the remaining rays will give red light and so on with the other complementary complementary com corn colors orange and blue yellow and violet Now If It the retina has been fatigued through being exposed exposed exposed ex ex- posed too long to the action of ot red ra rays s It will be susceptible only to the remaining six colors and the eye when Immediately struck by the white light will receive the Impression of the complementary green color Many other Influences are based upon the same principle Thus when looking for tor a long time through blue spectacles spectacles spec spec- spectacles Immediately after their removal nil all objects will appear yellow When the retina has been Irritated from gazIn gazing gazing gaz gaz- In ing at nt red fireworks the gay flames will look greenish after their tion |