An hour later he realized that sixty minutes had passed in which he had not been afraid. It was good to be working again, he thought, and then that thought faded away again as he returned to studying the sheaves of circuit diagrams and closely typed pages of specifications. It was not only work, it was hard work, and absorbing. Chandler knew enough about the very short wavelength radio spectrum to know that the device he was supposed to build was no proficiency test; this was for real. The more he puzzled over it the less he could understand of its purpose. There was a transmitter and there was a receiver. Astonishingly, neither was directional: that ruled out radar, for example. He rejected immediately the thought that the radiation was for spectrum analysis, as in the Caltech project--unfortunate, because that was the only application with which he had first-hand familiarity; but impossible. The thing was too complicated. Nor could it be a simple message transmitter--no, perhaps it could, assuming there was a reason for using the submillimeter bands instead of the conventional, far simpler short-wave spectrum. Could it? The submillimeter waves were line-of-sight, of course, but would ionosphere scatter make it possible for them to cover great distances? He could not remember. Or was that irrelevant, since perhaps they needed only to cover the distances between islands in their own archipelago? But then, why all the power? And in any case, what about this fantastic switching panel, hundreds of square feet of it even though it was transistorized and subminiaturized and involving at least a dozen sophisticated technical refinements he hadn't the training quite to understand? AT&T could have handled every phone call in the United States with less switching than this--in the days when telephone systems spanned a nation instead of a fraction of a city. He pushed the papers together in a pile and sat back, smoking a cigarette, trying to remember what he could of the theory behind submillimeter radiation. At half a million megacycles and up, the domain of quantum theory began to be invaded. Rotating gas molecules, constricted to a few energy states, responded directly to the radio waves. Chandler remembered late-night bull sessions in Pasadena during which it had been pointed out that the possibilities in the field were enormous--although only possibilities, for there was no engineering way to reach them, and no clear theory to point the way--suggesting such strange ultimate practical applications as the receiverless radio, for example. Was that what he had here? He gave up. It was a question that would burn at him until he found the answer, but just now he had work to do, and he'd better be doing it. Skipping lunch entirely, he carefully checked the components lists, made a copy of what he would need, checked the original envelope and its contents with the man at the main receiving desk for his safe, and caught the bus to Honolulu.