"When a roulette wheel is spinning rapidly, the ball can move freely between all possible positions. However, when the wheel slows down the ball will settle into one of the thirty-seven different positions."

"The ball behaves really in only one way which is rolling around and around. In other words, at low energies there are thirty-seven different states in which the ball can exist. And if we could only observe the ball at low energies, we would then think that there were thirty-seven different types of ball."-brief history of time

Now think about that with zoetrope =P
It has little windows and illustrations on the inside of the wheel that when spun make continuous movement into animation. Some really old ones used to have a flame on the inside of them.