OF VISION demonstrates how people can perceive a whole scene while
only seeing a part of it at one time. The exhibit has a long tube
with a slot at the end of it. The tube is held to one eye while
the user moves it back and forth rapidly with the slot oriented
vertically. Even though the slot restricts the view to only a small
part of the scene at any moment, the tendency of the eye to retain
images allows the observer to see the whole scene.