Plateau acknowledged that Faraday’s paper had some interesting observations which he explained and enlarged upon. Following the principle outlined in his work of 1828, Plateau then constructed the first Fantascope or Phénakisticope, the first machine which created illusions of motion from a series of pictures. Madou, a brother-in-law of Quetelet, was credited with copying Plateau’s drawing with extreme care. Plateau conceived the idea of having successively different pictures which would give the illusion of motion for use on the revolving disk. With each figure showing some changes of position from the preceding, the illusion is that the figures move and not the disk; and so it is with modern motion pictures. We have no consciousness of the movement of film through the machine before our eyes--only of movement of the figures on the film as projected on the screen. (Illustration facing page 89.) Plateau also pointed out that a strong light was necessary for the motion pictures--as today--and that the “projector” must be a certain distance from the mirror (now a screen) on which the images are seen. “I shall not describe the variety of curious illusion which can be produced by this new method,” Plateau concluded. “I leave to the imagination of persons who would try these experiences the care to find out the most interesting.” Motion picture producers down to this day, using their imagination, have followed the challenge of Plateau, and still the field is inexhaustible. In the _Annales de Chimie et de Physique_ for 1833 Plateau gave a further explanation of his device, named by others the Phénakisticope. Others had also commercialized it. McLeans’ Optical Illusions, No. 26 Haymarket Street, London, and other firms were selling models based on Plateau’s invention. “I wish to take this opportunity to state, that while the Phénakisticope has been made from an idea which I have published on this new method of creating illusions, I have no part whatsoever in the execution of this instrument which leaves much to be desired according to reports. The theory and experiments have shown that to obtain results as perfect as possible it is necessary to take certain precautions which have been omitted in the Phénakisticope.” Plateau went on to explain that he had made some models in which the necessary steps had been taken and “these models now constitute a new instrument which has been published in London under the name of Fantascope.” The improved instrument was described with the original dancer and marching men as illustrations. He also pointed out that the disks must revolve at a certain speed--if too slow, the illusion of motion is not present, and if too rapid the figures become blurred.