“It seems kinda funny to talk about the international situation,” remarked Carver. “Hell, there won’t be any international situation for several geological periods.”

“The inertial effect makes simultaneity a valid approximational concept,” declared Symonds pedantically. His habit of lecturing scientists and engineers on their professions had not endeared him to them. “If we spend a year in the past, we must necessarily return to our own era to find a year gone, since the main projector operates only at the point of its own existence which—”

“Oh, stow it,” said Greenstein. “I read the orientation manual too.” He waited until everyone had cards, then shoved a few chips forward and added: “druther spend my time a little nearer home. Say with Cleopatra.”

“Impossible,” Symonds told him. “Inertial effect again. In order to send a body into the past at all, the projector must energize it so much that the minimal time-distance we can cover becomes precisely the one we have covered to arrive here, one hundred and one million, three hundred twenty-seven thousand, et cetera, years.”

“But why not time-hop into the future? You don’t buck entropy in that direction. I mean, I suppose there is an inertial effect there, too, but it would be much smaller, so you could go into the future—”

“—about a hundred years at a hop, according to the handbook,” supplied Polansky.

“So why don’t they look at the twenty-first century?” asked Greenstein.

“I understand that that is classified information,” Symonds said. His tone implied that Greenstein had skirted some unimaginably gross obscenity.

Herries put his head out of the shower. “Sure it’s classified,” he said. “They’d classify the wheel if they could. But use your reason and you’ll see why travel into the future isn’t practical. Suppose you jump a hundred years ahead. How do you get home to report what you’ve seen? The projector will yank you a hundred million years back, less the distance you went forward.”

Symonds dove back into his book. Somehow, he gave an impression of lying there rigid with shock that men dared think after he had spoken the phrase of taboo.

“Uh…yes. I get it.” Greenstein nodded. He had only been recruited a month ago, to replace a man drowned in a grass-veiled bog. Before then, like nearly all the world, he had had no idea time travel existed. So far he had been too busy to examine its implications.

To Herries it was an old, worn-thin story.

“I daresay they did send an expedition a hundred million years up, so it could come back to the same week as it left,” he said. “Don’t ask me what was found. Classified: Tip-top Secret, Burn Before Reading.”

“You know, though,” said Polansky in a thoughtful tone, “I been thinking some myself. Why are we here at all? I mean, oil is necessary to defense and all that, but it seems to me it’d make more sense for the U.S. Army to come through, cross the ocean, and establish itself where all the enemy nations are going to be. Then we’d have a gun pointed at their heads!”