Authors: Larry Niven
Ra Chen said, “But now you've got a time machine.”
“And if I can't use the Institute, I'll have to break you up and sell the parts for what I can get.”
Ra Chen didn't seem surprised. “You'd get nothing but scrap prices.”
“How much do you spend just keeping the Center going? I'd save
that
much. It wouldn't save either of us, of course.”
4
On the other side of its glass wall, fifty feet of short-legged lizard half uncoiled, lifted its head high above them, and spat fire along the glass. Gorky and Ra Chen didn't appear to notice. Miya stared up at the beast in awe and wonder.
“We should change the label on this,” Svetz said, “now that Waldemar the Tenth is dead.”
“Isn't it a Gila monster?”
“No. I found him in another picture book, after I caught him. Dragon!”
“
You
caughtâ”
She cut herself off because Gorky was speaking. “You can change the past.”
“That's scary stuff, Willy! We've done that once or twice by accident,” Ra Chen said. “Anyway, what would you change?”
“Right after the first use of a thermonuclear bomb, there were experiments with thermonuclear rocket motors in North America Sector. We've
got
nuke rockets now. We could leave designs on some lab table in the Industrial Age for the locals to copy.”
“Why bother? Like you said, you've got them already.”
“But they had the
wealth.
Ra Chen, if they'd had nuke rockets then, they could have built an orbital solar power system for what they spent on cosmetics! With ten years to work, and for no more than the price of perfumes and lip goo and stuff to shape their hair into topiary, they'd have had free power from the sky and a fleet of spacecraft left over at the end!
“
Now
we're living too close to the edge. Too much farmland turned to dust and blew into the sea over the centuries. Too little sunlight gets down to us through the industrial goo. Today that same price would buy about ten million lives. People starve, or they freeze in the dark, when Bureaus divert power from the cities. We lose thousands of lives when we launch a Forward probe, and those are
cheap.
The Industrial Age,
then
was when we should have moved. They put twelve men on the Moon and then went home for four hundred years!”
“I know considerable about the Industrial Age,” said Ra Chen. “I've been
in
it. Hundreds of millions of people with thousands of insanely different lifestyles, all of 'em eleven hundred years dead. You'd have to get that kind of a mob moving all in one direction to persuade them to put a permanent base on the Moon instead of using perfume and lip goo and soap ⦠and sunblock, which isn't just a cosmetic. Are you really that persuasive, Willy? Go ahead, persuade me. But tell me this first. If you did change the past, how would you get the credit? The SecGen's memory would change too. You'd have nothing to show but a huge bill for electricity.”
“You thought of it too?”
Ra Chen barked laughter. “Everyone
thinks
of changing the past! If it weren't for temporal inertia we'd have exterminated ourselves once already, remember, Svetz? And maybe other times he never told me about.”
Miya was gaping, and Svetz grinned at her. Gorky must know the story already, if he knew about the torn cages.
Ra Chen said, “Willy, eleven hundred years ago you had thousands of ancestors. What if you do something to separate any two of them at the wrong time? You might edit yourself out. Or edit
me
out and find yourself stranded in the past.”
Gorky said nothing.
“The new Secretary-General wants the solar system. You
know
it could be worse. Any slip you make anywhere in the past, you could wind up with no time machine and a SecGen who collects torture devices.”
“All right,” Gorky said, “no changes.”
They walked in silence for a bit.
“Everything interesting happened eleven hundred years ago,” Willy Gorky said. “Industry exploded across the world. Human numbers went into the billions. Highways and railroads and airlines webbed the planet. All the feeble life-forms went extinct, but ideas boiled! There was every kind of scheme for the conquest of Space. Antimatter rocket engines, antigravity, solar sails, hundreds of tether designs, the Forward probes, Orion spacecraft, and a thousand things that
didn't
work but aren't
generically
impossible.”
Ra Chen mused. “Lost secrets?”
“Why not? The space elevator,
that
notion came from a country that was still medieval!”
“Space elevâ?”
“You know what I'd like to do with Mars? Use the planet as a test bed. Terraforming experiments, of course. Build a space elevator too. Build
all
of the skyhook launch schemes,
all
the ways of getting to orbit without rockets. They all have that much in common. They're all dangerous!
Huge
potential energies involved. You could build them all cheaper, in miniature, because Mars has low mass and a high spin. Try them on Mars, where they can't hurt anyone!
“The Industrial Age is over, the world isn't rich anymore, and we can't afford to experiment. But what have we forgotten? What miracles could we find by raiding old libraries? If you search through two thousand years of the past you're bound to find
something.
”
“Finding it is the problem,” Ra Chen agreed. “I built the big X-cage to raid the Library of Alexandria before Julius Caesar torched it. It turns out that we can't reach back that far. But we got to the Beverly Hills Library in plus-sixty-eight Atomic Era! We scooped it all up just before the quake and the wave. Why don't you set some of your people searching through those old books?”
“I will. What about the Pentagon or the Kremlin?
They
must have had interesting stuffâ”
“Secrets. Locked up, hidden and guarded. Willy, it's a mistake to think of armed men as dead.”
The albino whale in its huge tank turned sideways to focus one tiny eye on Svetz. Whale looked better than he had after the capture. The broken harpoons were gone, scars starting to heal.
Gorky rubbed his eyes. “I'm just getting used to thinking in terms of time. We're still just talking, right?”
“Râ”
“Aliens, I promised aliens to Waldemar Ten. Waldemar Eleven expects them too. Can your time machines find weirder animals than this?”
“Amazing beast,” Ra Chen said. Whale's eye turned to look at him.
“We
could
have billed it as alien. From Europa, maybe.”
“Willy, is there a chance at real aliens?”
“We haven't found life anywhere.”
“Mars?”
“Long ago. There's fossil bacteria in Martian rocks dating from half a billion years ago. It's very primitive stuff, Ra Chen. Mars had seas and a reasonable atmosphere for less than a billion years, and maybe what we found evolved then. Or maybe it all evolved on Earth and got to Mars embedded in a meteor. Not an alien at all.”
“Mars had life later than that,” Miya said.
They turned toward her. Svetz caught Gorky's indulgent smile.
Miya didn't. “There was life on Mars. There was civilization! We have sketches made from telescope observations and descriptions from old astronomers, Schiaparelli and Lowell and Burroughs.
Hundreds
saw channels running across Mars, too straight to be anything but artificial!
“And it all disappeared over the next sixty years, before the first probes reached Mars. The probes found river valleys, but they were dry. Craters everywhere. Almost no atmosphere, nothing left of the water system. Nothing left of the water. High cirrus, and frost at the poles.”
Willy Gorky told her gently, “A lot of these discoveries were made through the Lowell telescope in Arizona. Have you ever
looked
through a telescope at Mars?”
Miya shook her head. “I've never looked through a telescope.”
“Most astronomers don't. Miya, dear, Lowell's telescope didn't have camera attachments. Eyeballs! Everything was a blur. That was the period when they decided Mercury was like the Moon, one face always to the Sun. They were drawing one face of the planet onto the other and didn't notice! Those canalsâ” He was talking to the back of her head now. “Tired eyes want to connect the dots. We've never found anything on Mars.”
Watching her defeated expression, Svetz asked, “What if she's right?”
Willy Gorky laughed out loud. “Svetz, what do you know about other planets? Miya, you dug in those old river valleys! What did you find? Microscopic traces that might have been bacteria? Nothing else?”
“No, nothing,” Miya admitted. Her cheeks flamed. Her grip on Svetz's hand felt like desperation. “But we haven't searched the thousandth part of Mars!”
Svetz said, “We've found some amazing surprises in the past. Miya? Did this all disappear just as we were going into the Industrial Age?”
“That's right.”
Svetz threw up his hands. “If only we had a time machine!”
5
Single-minded as a spider, Lowell built his own observatory to map them and spun a whole theory from the web of lines that he created.
âWilliam K. Hartmann,
Mars Underground,
1997
Â
It should have been just that simple.
“I want to see martian civilization at its height,” Willy Gorky told them. “No, futz, we could get pictures like that from a computer! Ra Chen, show me video of Martians holding a funeral, then I'll send a team there to dig up the tomb in present time. If you're right, Miya. If there's a civilization. But if you could find
anything
alive â¦
anything
alien would get the SecGen off our backs for a long time. Svetz, a martian tool would do, or an animal. We've brought back soil samples from every large body in the solar system.”
To the left of the armory door was a cluster of chairs and little tables, and a drink and dole yeast dispenser. Svetz sipped coffee and waited ⦠but Ra Chen had developed the habit of letting Svetz deliver bad news.
So be it. Svetz told Willy Gorky, “We can't move an extension cage to Mars. The reach isn't there. There's no way to match velocities either.”
Willy said, “We can use Rovers and Orbiters. Where
can
you put an extension cage? Anywhere on Earth?”
Ra Chen said, “Northern Hemisphere and some of the Southern. Beyond that, the Earth's massâ”
“Orbit?”
“Haven't tried. We build the cages like spacecraft, though. It's all Space Bureau hardware. They'll stand up to vacuum.”
“Whale fitted into the big X-cage, didn't he? We can fit a module in thereâ”
“But not a launcher.”
“
Yes,
Miya. Ra Chen, didn't I see antigravity beamers on the large X-cage?”
“Yes.”
“Range?”
“How heavy is your probe module?”
“Pilgrims mass one hundred fifty tonnes, rocket and all. Twenty-two meters long, twelve meters diameter. I can assemble them in three months if you want them.”
“That's tiny compared to Whale.”
Gorky nodded. “I'll work out how many modules we want. We'll push the small X-cage back to before the Lowell observationsâ”
“Willy, will you settle for â550 AE? Seventeen hundred years ago, around five hundred years before Lowell.”
“Middle Ages. Why?”
“It's when Svetz picked up Snake. Before the American continents got into the history books. Nobody local will bother us if we operate over the open Pacific. The time machine wouldn't have to be reset. That saves us a week, and funding too, Willy. You build your Pilgrims right, they'll just sit on Mars with their cameras running, right through the Lowell and Mariner periods.”
“All right. The large X-cage homes on the small one? Good. Once you're in orbit you're halfway to anywhere.”
Organization was a skill Svetz had never tried to learn. It wasn't enough that things happen. They must happen in the proper order. Rocket motors must appear before a hull could be closed. Fuel couldn't just sit in a tank; compressors must be ready to produce it at the right time. Why was timing so difficult for the Institute for Temporal Research?
Svetz sat in on endless discussionsâ
“Now, here's the tricky part,” Ra Chen told Willy Gorky. “We launch the first load, then pull the big cage back empty. We load your next module inside, and we can take our sweet time doing it. Days, weeks, a year if there's a budget cut. Then we send it back to Miya and Svetz in the moment following the first launch. Launch again the same way. Or send it back to ten hours later, give them a sleep break.”
“You can
do
that?”
Ra Chen smiled a fat ruddy smile. “Time travel is wonderful, isn't it?”
*Â Â Â *Â Â Â *
Three months stretched to four, and wouldn't stretch further because the Secretary-General's annoyance was becoming overt. And one morning they were ready.
6
The new extension cage was transparent nearly to invisibility. It was no smaller than the old extension cage, which had once held Svetz and an angry Horse. But Svetz and Miya were nestled in the bottom of a spherical shell, and that might have felt crampedâ
“Cozy,” Miya said. “Why isn't one of us in the control chair?”
Svetz smiled. “You'll see when we get moving.”
She nudged Svetz's bag with her foot. “What did you bring?”
“Food, medical, and the trade kit. You?” He waved at the upper curve, where bubble helmets and the pelts of two rubber men were splayed out on stickstrips. “I haven't trained with pressure suits.”