speeded-up effects. Like other motion simulation devices, the zoetrope depends on the fact that the human retina retains an image for about a tenth-of-a-second so that if a new image appears in that time, the sequence was seem to be uninterrupted and continuous. It also depends on what is referred to as the Phi phenomenon, which observes that we try to make sense out of any sequence of impressions, continuously relating them to each other.
