This trick of second sight he claims body and soul, as the favorite child of his brain. He even goes as far as to relate a story to prove that the trick came to him in the form of an inspiration. I quote directly from the American edition of his "Memoirs," page 255: "My two children were playing one day in the drawing-room at a game they had invented for their own amusement; the younger had bandaged his elder brother's eyes and made him guess the objects that he touched, and when the latter happened to guess right they changed places. This simple game suggested to me the most complicated idea that ever crossed my mind. Pursued by the notion, I ran and shut myself in my workshop, and was fortunately in that happy state when the mind follows easily the combinations traced by fancy. I rested my head in my hands, and in my excitement laid down the first principles of second sight." [Illustration: Robert-Houdin and his son Emile, presenting second sight. Here the bell is used as it was by Henri Robin. From an illustration in the original French edition of the Robert-Houdin "Memoirs."] Then, picking up the long idle quill of Baron Munchausen, he proceeds to explain the methods by which he perfected the trick and trained his son. To the layman these methods read most entertainingly. To the experienced conjurer or his humblest assistant they appeal as absurd and impossible, a sheer waste of time, of which a man who reproduced the tricks of his predecessors as rapidly as Robert-Houdin did, would not be guilty. [Illustration: Robert and Haidee Heller from photographs taken at the time that they were presenting second sight according to the Robert-Houdin method by an electric code. From the Harry Houdini Collection.] He claims to have trained the eye and memory of his son, by leading the latter past shop windows, and after allowing him one glance, demanding the names of articles seen at this single glance. When the boy could mention forty things after passing the window, his education was pronounced good. Robert-Houdin also tells in his "Memoirs" of spending hours with his son in poring over an enormous collection of coins, medals, etc., which severe lesson helped them both in future performances. To the conjurer, this tale is farcical. Not only was there no need of forcing the boy to become a coin expert, but the task was one which could not be accomplished in the brief time which Robert-Houdin allowed himself for perfecting the trick. The only knowledge required about coins is to recognize a coin when you see it. Some one may hand a coin of peculiar stamp, and the operator must signal to his medium the metal and all he knows about it. Of course, if both know the various coins, then they can understand each other with less signaling than if the coins were unfamiliar to either.