He wondered whether Linda's surmise that the Lower Temple era had possessed optical instruments would prove correct. Or whether the natives had simply had good eyes.

What had they made of the thing? Henry buried his head in his pillow. If the Quraquat had looked at their moon through a telescope, they would have seen a city occupying the center of a vast plain. They would have seen long airless avenues and rows of buildings and broad squares. And a massive defensive wall.

He turned over. Eventually Oz would surface in Quraquat mythology and literature. When we've collected enough of it. And mastered the languages.

His stomach tightened. There would not be time.

The anomaly was only rock, cunningly hewn to create the illusion of the city. There was the real puzzle. And the explanation for Oz lay somehow with the race that had inhabited this world. This was a race that had built complex cultures and developed philosophical systems that had endured for tens of thousands of years. But its genius did not extend to technology, which had never risen much beyond a nineteenth-century level.

The door chimed. "Henry?" The voice in the speaker was tense with excitement. "Are you asleep?"

"No." He opened the door. "Did we get in?"

"Yes—"

Henry threw back his sheet. "Give me two minutes. I didn't think it would be this quick."

Frank Carson stood in the corridor. "You have a good crew down there." In the half-light, he looked pleased. "We think it's intact."

"Good. That's goddam good." He turned on his table lamp. Beyond the window, sunlight filtered down from the surface. "Did you see it?"

"Just a peek. We're saving it for you."