This exhibit is as much a piece of kinetic sculpture as a demonstration in optics. Three beams of light are aimed into a slowly rotating high-dispersion prism, resulting in a number of images on the screen surrounding the prism and the lamps. As the prism rotates between the three lights, six different rainbows appear at one time or another. After they appear, they come to a stop and then reverse. Notice that the rainbows are caused by the light passing through the prism. In addition, light is reflected by the prism which produces the uncolored moving image of the three lights . After you stop the prism by pushing the button, you can discover where the images come from by blocking each of the lights with the card. Notice that each of the rainbows moves to a limiting position and seems to stay there for awhile and then retraces its steps.