Silver Ball Mystery

The magician shows a small box to his spectators. He opens it and removes two red dice, two small metall rings and a little steel ball. The box is now empty. It is closed and given to a spectator, who is asked to pay attention for it. The magician now forms a little tube from the two metall rings. First the little steel ball is placed on one of the dice, then the tube is put over dice and steel ball. At last the second dice is thrown into the tube. When the magician now places the whole stuff apart the spectators recognize that the steel ball has vanished! Even closest examination of the props doesn't bring the little ball back. The ball reappears within the box held by the spectator!