Von Stein let his hands rest upon the desk top--a surface covered with levers, electric switches, push buttons, and contrivances the nature of which Parker could not guess. The doctor leaned forward. He threw over a switch. The lights in the room became less bright. He pressed a button. The Danse Macabre of Saint-Saens floated weirdly upon the air, as though the music came from afar off. "Is that part of the treatment?" asked Parker, with a faint smile. "It's not cheering, exactly." "Merely an idiosyncrasy of mine," answered Von Stein, showing his teeth. "Before anything is done I must, in order to aid the receptivity of your mind, go a little further with the explanation of certain things which I mentioned the other day. I promise not to bore you. More than that, Mr. Parker, I promise that you will be more interested than you have ever been in anything!" * * * * * It seemed to Parker that there was something sinister in the manner and speech of Dr. von Stein. The Dance of Death! Did that music have a meaning? Impossible! It was only his own sick mind that was allowing such thoughts to come to him. "Anything that will help," he murmured. "You have noticed that copper bowl?" Von Stein did not wait for a reply. "The misty appearance inside and underneath it is given by thousands upon thousands of minute platinum wires. When it is in use a slight electrical current is passed through it, varying in power according to the rate of vibration needed. That instrument, my dear sir, is a transmitter of thought. I may call it the microphone of the mind. I can tune in on any mind in the world, by experimenting up and down the vibration range to determine the susceptibility of the particular person. The human mind does not need an amplifier, as the radio receiving set does. Rather, it acts as its own amplifier, once having received the thought. I invented one, however, to prove that it could be done. I equipped Heinrich with it and in half an hour by suggestion reduced him to his present state of docile stupidity. I have, Mr. Parker, the means of moving people to do my bidding!" * * * * * Von Stein stopped abruptly, as though for emphasis and to allow his astounding statements to take effect. Parker sat stunned, struggling to grasp all the implications of what he had just heard. Suddenly they became clear. He saw events in order, and in relation to each other. "So that's how it was with Cordelia Lyman!" he cried hoarsely, leaning forward. "And it was you who had that money from Fleming Proctor!" "You are not unintelligent," remarked Dr. von Stein. "Better that science should have the Lyman money than a few old women of no particular use. As for Proctor, he was a fool. I would have protected him." "And my pictures ... my book...." "I can cure you, Mr. Parker. _If I will!_" "And anyone is at the mercy of this man!" groaned Parker.