Walt laughed hugely and hugged her. Christine was lissome in the curve of his arm as she relaxed against him. Walt looked down at her for what seemed to be a long time while the stream of highly-technical thinking and deduction gave way to a series of more fundamental thoughts. Then he added his other arm to the embrace, and Christine turned to face him. He kissed her gently; experimentally--and discovered instead of resistance there was co-operation. His kiss became fervent and Christine's lips parted beneath his. Some minutes later, Christine leaned back in his arms and smiled at him affectionately. "I was wondering if you'd ever get around to that," she said softly. Walt grinned. "Have I been had?" "I had Jim pack the all-white shotgun," she told him. "Shucks, why not just have him threaten to sit on me?" asked Walt. He kissed her again. "Now," she said after an appropriate and pleasant interval, "just what was my 'thought for the week'?" "Kingman," he said, his forehead creasing in a frown. "Kingman?" "We've no corner on brains," said Walt. "Anybody tinkering with these energy tubes might easily devise the same thing. Kingman's immediate thought would be to freeze us out, I betcha." Walt kissed her again and then let her go, "Let's do some juggling with figures," he said. "What kind of?" "The Laws of Probability aided by a bit of sheer guesswork and some shrewd evaluation of the barrister's mind." Christine smiled. "You can speak plainer than that," she said. "I know," he replied, reaching for his bag of gear, "but there's a lady present." "You forget that the lady thought of it," Christine pointed out. "So let's go and find the--barrister." "It ought to show, though," observed Walt. "And yet, my lady, we can check whether there has been cross-duggery at the skull-roads by making a brief observation along here somewhere." "How?" "Well, about fifty yards up this corridor there is a wall-thermostat." "You think that if Kingman were trying to chill-off the place, he'd have bollixed the thermostats so they can't heat up the place and compensate?" Walt nodded. "He'd do it, not knowing that we had all the near-by circuits shut off for our own experiment, no doubt." "You don't suppose Kingman knew about this idea and decided to add to the general effect?" asked Christine. Walt shook his head. "He'd assume that someone would be rambling up here off and on to look at the works. He'd automatically choose another place if he thought we had this one under observation." Walt stopped at the thermostat and with a screwdriver he removed the face of the instrument. He reached down into his tool-pocket and took out a long, slender pair of tweezers. He probed in the depths of the thermostat and come out with a tiny square of paper. He held it up for Christine to see. "Stickum on one side held it until the contacts closed," he said. "Then it made a darned good insulator. Betcha this slip of paper came from Terran Electric!"