The displacement fields are ready, tightbeamed Orphu. I’ll set them to point-eight-g on ship lateral and go to Earth-normal internal pressure. By the time you two get in the forward airlock, everything will be breathable and comfortable for him.

“Isn’t this too large for the mission they were talking about?” said Hockenberry. “Even with hundreds of rockvec soldiers aboard, this seems like overkill.”

“We may want to bring things back with us,” said Mahnmut. Where are you? he sent to Orphu.

I’m on the lower hull now, but I’ll meet you in the Big Piston Room.

“Like rocks? Soil samples?” said Hockenberry. He’d been a young man the week human beings had first set foot on the moon. Memories came back now of him sitting in the backyard of his parents’ house and watching the ghostly black-and-white images from the Sea of Tranquility on a small TV on the picnic table, extension cord running to the summerhouse, while the half-full moon itself was visible above through the leaves of the oak tree.

“Like people,” said Mahnmut. “Perhaps thousands or tens of thousands of people. Hang on, we’re docking.” The moravec silently commanded the holoports off; attaching at right angles more than one thousand feet up the vertical hull of a spacecraft was a view that would give anyone vertigo.

Hockenberry asked little and said less during his tour of the ship. He’d imagined technology beyond his imagining—virtual control panels that disappeared at the flick of a thought, more energy-field chairs, an environment built for zero-g with no sense of up or down—but what he saw felt like some gigantic Nineteenth or early-Twentieth Century steamship. What it felt like, he realized, was a tour of the RMS Titanic.

Controls were physical, made of metal and plastic. Couches were clunky, physical things—enough, it looked like, for a crew of about thirty moravecs—the couch proportions were never really right for humans—along with long storage bins with metal-and-nylon bunks along bulkheads. Entire levels were set aside with high-tech-looking racks and sarcophagi for a thousand rockvec troopers, Mahnmut explained, who would make the trip in a state somewhere above death but below consciousness. Unlike their trip to Mars, the moravec explained, this time they were going armed and ready for battle.

“Suspended animation,” said Hockenberry, who’d not avoided all sci-fi movies. He and his wife had had cable there toward the end.

“Not really,” said Mahnmut. “Sort of.”

There were ladders and broad stairways and elevators and all sorts of anachronistic mechanical devices. There were airlocks and science rooms and weapons’ lockers. The furniture—there was furniture—was large and clunky, as if weight were no problem. There were astrogation bubbles looking out toward the rim walls of Stickney and up toward Mars and down toward the gantry lights and moravec bustle. There were mess halls and cooking galleys and sleeping cubbies and bathrooms, all of which, Mahnmut hurriedly explained, were for human passengers, should they have any coming or going.

“How many human passengers?” asked Hockenberry.

“Up to ten thousand,” said Mahnmut.

Hockenberry whistled. “So is this a sort of Noah’s ark?”

“No,” said the little moravec. “Noah’s boat was three hundred cubits long by fifty cubits wide by thirty cubits tall. That translates to about four hundred fifty feet in length, seventy-five feet in width, and forty-five feet high. Noah’s ark had three decks comprising a volume of about one million four hundred thousand cubic feet and a gross tonnage of thirteen thousand nine hundred and sixty tons. This ship is more than twice that long, half again that width in diameter—although you saw that some sections, like the habitation cylinders and holds, are more bul-bous—and masses more than forty-six thousand tons. Noah’s ark was a rowboat compared to this craft.”

Hockenberry found that he had no response to this news.

Mahnmut led the way into a small steel-cage elevator, and they descended through level after level past the holds, where Mahnmut explained his Europan submersible The Dark Lady would go—and down through what the moravec described as “charge storage magazines.” The word “magazine” had military connotations for Hockenberry, but he assured himself that it couldn’t be that. He saved his questions for later.

They met Orphu of Io in the engine room, which the larger moravec called the Big Piston Room. Hockenberry expressed his pleasure at seeing Orphu with his full complement of legs and sensors—sans real eyes, he understood—and the two talked about Proust and grief for a few minutes before the tour resumed.

“I don’t know,” Hockenberry said at last. “You once described the ship you took in from Jupiter, and it sounded high tech beyond my understanding. Everything I’m looking at here seems… looks like… I don’t know.”

Orphu rumbled loudly. When he spoke, Hockenberry thought, not for the first time, that the huge moravec sounded Falstaffian.

“It probably looks like the engine room of the Titanic to you,” said Orphu.

“Well, yes. Should it?” said Hockenberry, trying not to sound more ignorant of such things than he was. “I mean, your moravec technology must be three thousand years beyond the Titanic. Three thousand years beyond my end-time in the early Twenty-first Century even. Why this… this?”

“Because it’s based largely on mid-Twentieth Century plans,” rumbled Orphu of Io. “Our engineers wanted something fast and dirty that would get us to Earth in the least possible time. In this case, about five weeks.”

“But Mahnmut and you once told me that you zipped in from Jupiter space in days,” said Hockenberry. “And I remember you talked about boron solar sails, fusion engines… a lot of terms I didn’t understand. Are you using those things in this ship?”

“No,” said Mahnmut. “We had the advantage coming in-system of using the energy from Jupiter’s flux tube and a linear accelerator in Jovian orbit—a device our engineers have been working on for more than two centuries. We don’t have those things going for us here in Mars orbit. We had to build this ship from scratch.”

“But why Twentieth Century technology?” asked Hockenberry, looking at the huge pistons and driveshafts gleaming up toward the ceiling sixty or seventy feet overhead in the giant room. It did look like the engine room in the Titanic in that movie, only more so—bigger, more pistons, more gleaming bronze and steel and iron. More levers. More valves. And there were things that looked like giant shock absorbers. And the gauges everywhere looked like they measured steam pressure, not fusion reactors or some such. The air smelled of oil and steel.

“We had the plans,” said Orphu. “We had the raw materials, both brought from asteroids in the Belt and mined right on Phobos and Deimos. We had the pulse units …” He paused.

“What are pulse units?” asked Hockenberry.

Big mouth, sent Mahnmut.

What, do you want me to hide their presence from him? sent Orphu.

Well, yes… at least until we were a few million miles away from here toward Earth, preferably with Hockenberry on board.

He might notice the effect of the pulse units during our departure and get curious, sent Orphu of Io.

“The pulse units are… small fission devices,” Mahnmut said aloud to Hockenberry. “Atomic bombs.”

“Atomic bombs?” said Hockenberry. “Atomic bombs? Aboard this ship? How many?”

“Twenty-nine thousand seven hundred in the charge storage magazines you passed through on the way to the engine room,” said Orphu. “Another three thousand and eight in reserve stored below the engine room here.”

“Thirty-two thousand atomic bombs,” Hockenberry said softly. “I guess you guys are expecting a fight when you get to Earth.”