"We'll do it ourselves," said Russ. "When we're the only ones here, we can be sure there won't be any leak." It took hours of work on the math machines, but at the end of that time Russ was certain of his ground. "Now we go to work," he said, gleefully. In a week's time they had built a triple televisor, but simplifications of the standard commercial set gave them a mechanism that weighed little more and was far more efficient and accurate. During the time the work went on they maintained a watch over both the office of Spencer Chambers and the laboratory in which Dr. Herbert Craven worked 16 hours a day. Unseen, unsuspected, they were silent companions of the two men during many hours. They read what the men wrote, read what was written to them, heard what they said, saw how they acted. Doing so, the pair in the high mountain laboratory gained a deep insight into the characters of unsuspecting quarries. "Both utterly ruthless," declared Greg. "But apparently men who are sincere in thinking that the spoils belong to the strong. Strange, almost outdated men. You can't help but like Chambers. He's good enough at heart. He has his pet charities. He really, I believe, wants to help the people. And I think he actually believes the best way to do it is to gain a dictatorship over the Solar System. That ambition rules everything in his life. It has hardened him and strengthened him. He will crush ruthlessly, without a single qualm, anything that stands in his path. That's why we'll have a fight on our hands." * * * * * Craven seemed to be making little progress. They could only guess at what he was trying to develop. "I think," said Russ, "he's working on a collector field to suck in radiant energy. If he really gets that, it will be something worth having." For hours Craven sat, an intent, untidy, unkempt man, sunk deep in the cushions of an easy chair. His face was calm, with relaxed jaw and eyes that seemed vacant. But each time he would rouse himself from the chair to pencil new notations on the pads of paper that littered his desk. New ideas, new approaches. The triple televisor was completed except for one thing. "Sound isn't so easy," said Russ. "If we could only find a way to transmit it as well as light." "Listen," said Greg, "why don't you try a condenser speaker." "A condenser speaker?" "Sure, the gadget developed way back in the 1920s. It hasn't been used for years to my knowledge, but it might do the trick." Russ grinned broadly. "Hell, why didn't I think of that? Here I've been racking my brain for a new approach, a new wrinkle ... and exactly what I wanted was at hand." "Should work," declared Greg. "Just the opposite of a condenser microphone. Instead of radiating sound waves mechanically, it radiates a changing electric field and this field becomes audible directly within the ear. Even yet no one seems to understand just how it works, but it does ... and that's good enough."