From left to right, up to bottom, here are videos: The first group of deflectors The corresponding ball arrive by the left, and pass left or right of the deflector. We have already 4 possibilities (1 deflector + 1 choice between two balls) The second group of deflectors The balle arrive into the second deflector group, which dichotomize one more time the possibilities, there is now 8 possibilities. How does the outside of the machine works One see the ball going into the machine, the black box, and going out of it, in order to be lifted. Opening of the machine, and step-by-step video. Explication of 1/8th of the black box, everything is similar.