Tag: optical illusion

An Optical Illusion

Here is a simple way to observe the persistence for a perceptible length of time of every impression made upon the retina. Gaze fixedly for a minute or so at the black diamond in the center of the figure, and then turn your eyes quickly to a white wall or sheet of paper, and you …

Continue reading

Bad Behavior has blocked 5857 access attempts in the last 7 days.