The defective tube was now innocently reposing in the key position of Circuit No. 13; it wouldn't be detected until that circuit was used. Even Urei would fail to realize its presence in his innards until the circuit was energized. And when that happened, half the control board would be momentarily out of operation. Gongs would ring then, and a brilliant red lamp would light, showing the exact position of the breakdown. A technician would get a new tube and replace the old one. Urei would be whole again.... Unless.... Benton glanced at his watch. "It's about time for lunch," he called; "let's knock off now. We can run a few test problems when we get back, and still have time to finish the other half of the board before quitting time. In fact if we finish early you can all go home; we can run the second test in the morning." One man suggested cutting the lunch in half. The others, seeing a short day in the offing, loudly agreed. Benton smiled and nodded, quite as if there was nothing more urgent on his mind. * * * * * He then reported to Dr. Albie. There were two reasons for that. One was to make certain that he would have a chance to talk the master physicist out of any objection he might have to continuing with the remaining half of the operation this afternoon. The other was that he wanted to keep his mind active on subjects which wouldn't reveal the fact that there was something going on back of his surface thoughts. "You certainly made progress," the doctor complimented; "I expected it to take a couple days at least." Benton smiled ruefully. "It has," he said. "If you want to count the sleep I lost planning this so that there wouldn't be a minute wasted once we started. You know, there ought to be a way to make that show up on pay day." Dr. Albie nodded. "Can't be done on this kind of a job," he regretted. "But we can do the next best thing, just as we've always done." Benton smiled, then got a quick scare as he realized that he had relaxed for an instant. Immediately he forced his mind to contemplate the war which Urei had assured him was inevitable. It was the only thought which would account for the one which had sprung into his mind unheralded, and also give a reason for experiencing his sudden fright. Dr. Albie had referred to a little strategy of theirs which compensated them for any overtime they were forced to put in. It consisted of taking an equal amount of time off, while they covered for each other. It was their only expedient, since their salaries were fixed and allowed for no extra pay for extra work. Unfortunately the thought gave rise to a feeling of regret that shortly they would have no more reason for such subterfuge, inasmuch as they would no longer have jobs. The thought had progressed just that far when Benton realized that he had let his guard down.