“They see the Odinfold flyer,” said Rigg, “and all they can see of us is a couple of people standing in the doorway. As far as they know, we’re transporting mice for some kind of mousemoot.”
Umbo turned back to face the others. “Should we do it?” he asked.
“Transport the mice with us into the past?” asked Loaf. “We gave our word.”
“We don’t even know if we can do it,” said Umbo.
“Of course we can,” said Rigg. “If we can take Loaf with us, we can take anybody.”
Loaf smiled wanly.
“When should we travel to?” asked Umbo. “How far into the past are we going to take them?”
“As soon after we got control of the Wall as possible, I suppose,” said Rigg.
Umbo noticed the way he said “we.” As if anybody but him had any power over it. “I don’t carry a perfect calendar in my head,” said Umbo. “Why not just go through now, a year or so before the Visitors arrive?”
“Because the mice want more than a few of their generations to get established,” said Loaf. “They want to take ten thousand mice through the Wall, so they’ll have millions in place before the Visitors come.”
“That’s what the mice want,” said Umbo.
“We gave our word,” said Param.
“Based on information they gave us,” said Umbo. “And what the expendables and the ship told us.”
“Umbo has a point,” said Rigg. “Not the point he thinks he’s making—we’re going to keep our word, or at least I am. But we don’t know if we can take ten thousand mice into the past. Or even fifty. And how will we pinpoint when to arrive?”
“Just . . . hook on to some path, like you always do,” said Umbo.
“What path?” asked Rigg. “How do we know which of the paths that come near the Wall are from that time, or even close to it?”
“Take the flyer back with us,” said Olivenko, “and when we get there, ask it if we hit the right time.”
“No,” said Umbo. “If we arrive at a time before Rigg got control of the ships, then the flyer doesn’t have to do anything we say.”
“But it’s the flyer from now, from the future of that time,” said Olivenko.
“Machines aren’t people,” said Umbo. “It will sync up with the starship computers of that time and do what they tell it to do—and they won’t be obeying Rigg. They won’t even know who Rigg is.”
“We’re so powerful,” said Param. “But now we want to be all-knowing, too.”
“Well, it would be nice,” said Rigg.
“I think we need to fly back to where we came through the Wall from Vadeshfold,” said Umbo, “and go back to that time, where Rigg can see our own paths coming through the Wall.”
“But we won’t have the mice there,” said Loaf.
“They assembled here,” said Umbo. “Let them assemble there.”
“And then how long will it take them to travel here to the Larfold Wall?” asked Loaf. “They have little tiny legs.”
“I stay here,” said Umbo. “Rigg flies back there. Rigg hooks onto our paths. I push Rigg back, complete with the flyer. Rigg flies back here in that time, and then when he gets here, I pull him back to this time.”
“So much rigmarole,” said Olivenko.
“It’s the only way Rigg can go back and then get back to this time exactly,” said Umbo. “I’m still needed for that—the ability to stay in the present and send somebody else into the past. When Rigg comes back to the present, his own path will be here, at the Wall, and then we can take the mice back. Even if we can only take twenty or fifty or a hundred at a time, I can send Rigg back with the mice again and again, bring Rigg back to the present, and send him again.”
“I wish I could sense paths through the curvature of the planet,” said Rigg. “I can see them through hills, but they get faint and then invisible as more and more planetary mass gets between me and them.”