A large pane of glass some nine by six feet in area, and set in a frame, made to represent that of a window, is placed on the stage, about eighteen inches from the floor. Thirty-six inches from the ground a wooden shelf is placed against the window. An assistant--usually a woman--then mounts on the shelf and, looking out of the glass, proceeds to kiss her hand vigorously. The operator in a shocked voice asks her to desist. She refuses and, to the amusement of the audience, carries on her pantomimic flirtation more desperately than before. The operator pretends to lose his temper, and snatching up a screen places it at the back of her. He then fires a pistol, pulls aside the screen, and she has vanished. As the top, bottom and sides of the window, all in fact except the very middle, have been in full view of the audience, and as the window has been tightly closed all the time, the disappearance of the girl completely mystifies the audience. Curtis explained it all. He pointed out that the keynote to the illusion lay behind the wooden shelf, which was so placed as to conceal the fact that the lower part of the window was made double, the bottom of the upper part being concealed from view by a second sheet of silvered glass placed in front of it. The shelf covers the line of junction and enables the window frame to be scrutinized by the audience. As soon as the screen is put in front of the lady on the shelf--the glass pane slides up about a foot and a half into the top of the frame, purposely made very deep. The bottom of the window is cut away in the middle, leaving an aperture about two feet square, which was previously hidden from view by the double glass at the base. Eve makes her exit through this hole, and slides on to a board placed behind the window in readiness for her. The pane of glass then slides down again, the screen is removed, and the window appears just as solid as before. When Curtis concluded his verbal explanation he gave the audience a practical illustration of how the thing was done; he manipulated the screen and pistol, whilst Hamar posed as Eve, and directly he had finished there was another outburst of applause. Kelson dared not look at John Martin or Gladys. The brief glance he had taken of them at the conclusion of the giving away of the first trick had shocked him--and he purposely stood with his back to them. With Hamar it was otherwise--the joy of triumph was strong within him, and the picture of John Martin, leaning forward in his chair, with his mouth half open and a dazed, glassy expression in his eyes, only thrilled him with pleasure; he laughed at the old man, and still more at Gladys. "That's the way to treat a girl of that sort," he whispered to Kelson; "scoff at her--scoff at her well. Let her see you don't care a snap for her--and in the end she'll run after you and haunt you to death." "I'm not so sure," Kelson said. "It might act in some cases, perhaps, but I don't think you can quite depend on it."