They were interrupted by the sudden appearance of a laboratory technician who brought in a dry photographic print still warm from the developing box. He laid it on the desk before Underwood. "I thought you might be interested in this." Underwood and Terry glanced at it. The picture was of the huge, gemlike artifact, but a number of the facets seemed to be covered with intricate markings of short, wavy lines. Underwood stared closer at the thing. "What the devil are those? We took pictures of every facet previously and there was nothing like this. Get me an enlargement of these." "I already have." The assistant laid another photo on the desk, showing the pattern of markings as if at close range. They were clearly discernible now. "What do you make of it?" asked Underwood. "I'd say it looked like writing," Terry said. "But it's not like any of the other Stroid characters I've seen--which doesn't mean much, of course, because there could be thousands that I've never seen. Only how come these characters are there now, and we never noticed them before?" "Let's go out and have a look," said Underwood. He grasped the photograph and noted the numbers of the facets on which the characters appeared. In a few moments the two men were speeding toward the surface of their discovery astride scooters. They jockeyed above the facets shown on the photographs, and stared in vain. "Something's the matter," said Terry. "I don't see anything here." "Let's go all the way around on the scooters. Those guys may have bungled the job of numbering the photos." They began a slow circuit, making certain they glimpsed all the facets from a height of only ten feet. "It's not here," Underwood agreed at last. "Let's talk to the crew that took the shots." They headed towards the equipment platform, floating in free space, from which Mason, one of the Senior Physicists, was directing operations. Mason signaled for the radiations to be cut off as the men approached. "Find any clues, Chief?" he asked Underwood. "We've done our best to fry this apple, but nothing happens." "Something _did_ happen. Did you see it?" Underwood extended the photograph with the mechanical fingers of the spacesuit. Mason held it in a light and stared at it. "We didn't see a thing like that. And we couldn't have missed it." He turned to the members of the crew. "Anyone see this writing on the thing?" They looked at the picture and shook their heads. "What were you shooting on it at the time?" Mason glanced at his records. "About a hundred and fifty angstroms." "So there must be something that becomes visible only in a field of radiation of about that wave length," said Underwood. "Keep going and see if anything else turns up, or if this proves to be permanent after exposure to that frequency." Back in the laboratory, they sat down at the desk and went through the file of hundreds of photographs that were now pouring out of the darkroom.