"Why not?" she demanded coldly. "What I expect to see may be something quite momentary. I can’t risk having anyone else as main observer. Peter, you’ll be in the observing booth, and I want you to keep your eye on the opposite side of the circle. General Kallner, I’ve arranged for motion pictures to be taken of each robot, in case visual observation isn’t enough. If these are required, the robots are to remain exactly where they are until the pictures are developed and studied. None must leave, none must change place. Is that clear?"