"Take, for instance," he continued eagerly, "that ray with which I drew you and your plane to me. That ray is the pure power of magnetism. At full strength it will draw anything to it instantly. Fortunately the power can be regulated: I can switch a lever in my laboratory and draw things to me, via the ray, at any speed I wish—one hundred, two hundred, a thousand miles an hour."
"How far can you throw the ray?" asked Foulet, and I knew he was thinking of that glider that rose from the roof-tops of Constantinople. Fraser also knew he was thinking of that.
"I did not draw the glider," he said quietly. "The airplane I sent did that. My airplanes carry batteries of this ray. In the beginning I found gliders to be more practical for my purposes than airplanes. For one thing they were silent. My only problem was that of getting them off the ground. Once they were in the air I could manage everything. It was this problem that inspired this discovery and perfection of the ray. But, you asked how far I can throw the ray? This main lamp, that I operate myself from here, is effective at two hundred miles. At one hundred miles it enjoys its full power."
"And you can draw anything to you," asked Brice, "within the radius of the magnetic ray?"
"Anything in the air," answered Fraser. "But of course I must use caution. Great caution. If I drew planes to me indiscriminately I would draw attention to myself; my secret and my location here would leak out. No. That must not be. So the only planes I bring are my own—and yours." He paused and his black eyes, again glassy, swept over us. "It is a compliment I pay you," he said finally. "You have become too troublesome. You know too much. Sooner or later the time would come when you would combine your forces. That would be a nuisance. So I decided to bring you here."
"Suppose," asked Foulet curiously, "we hadn't fallen into your trap? Suppose we had turned back before reaching the point where your ray is effective?"
Fraser shook his head and that smug, offensive smile appeared again. "You were trapped from the beginning, though you didn't know it," he said. "The plane you were following was equipped with batteries of the ray which, while not as powerful as the lamp I have here, were still powerful enough to hold you to the course we choose you to run. But enough of the ray," he added impatiently. "There are one or two other things I want to explain and then—" he paused and the pause, somehow, was alive with menace. What was he going to do after he had finished treating us as honored guests? For the third time he answered my unspoken question. His eyes narrowed till they were black, glittering slits. His voice, as he leaned toward us, was no more than a hissing whisper.
"Slaves!" he said, and his lips twisted. "How will you like to be slaves of Mad Algy Fraser?" He laughed—a chuckle that started in his throat and rose and rose till it seemed to shatter my ear-drums. I felt my teeth grinding together and my nails bit my palms in my effort to control my nerves against the strain of that maniacal glee. Suddenly he sobered. His laugh died instantly like a radio that had been snapped off. "Listen and I will tell you. I will tell you everything because it is necessary for you to know so that you may work for me intelligently and you will remember better and be of greater use to me if I tell you now while you are yet—sane!"