can hold Mars, let alone Earth."

Auger glanced awkwardly in Floyd's direction. "There's a complication at my end as well. I've brought someone into the chamber."

"I hope whoever you're bringing back is already in the loop."

"I think it's fair to say he's pretty f.u.c.king out of the loop. Remember that detective I mentioned?"

Skellsgard grimaced and closed her eyes, like someone waiting for a balloon to pop. "I'm not hearing

this, Auger."

"I couldn't shake him. He's what you'd call tenacious."

"You can't do this, Auger. The censor-"

"The censor let him through," Auger said. "He's already seen the ship, and the robot. The damage is

done."

"You have to send him back."

"I'm planning on it. But we're in a siege situation here. Floyd can't get back to the surface, and more

than likely people are already trying to break through into the outer chamber. I'm not sure whether they'll try to get through the censor, but I've tasked the robot to protect Floyd until we can send back a ship with reinforcements."

Skellsgard's image broke up, then rea.s.sembled. Her voice sounded thin, like someone speaking through a comb. "Caliskan won't OK it."

"I'll deal with him. I'll come back myself if I have to. I'd send the d.a.m.ned robot out to take Floyd all the way to the surface if the censor would let it through."

"May I say something?" Floyd asked.

"Go ahead," Skellsgard replied.

"Auger isn't giving you the whole picture. Fact of the matter is, she's pretty badly hurt."

"He telling the truth?" Skellsgard said, turning her perceptive gaze on Auger.

"It's nothing serious," Auger said, then immediately winced as the robot began to examine the wound. Even Floyd had to look away: he had never been very good with injuries, and it had been as much as he could do to clean and bandage the wound for her earlier.

"That doesn't look like 'nothing serious' to me," Skellsgard said.

"I'll keep until I'm home. At least this way I can stay conscious for some of the trip. The robot's patching me up. Can the ship take care of itself?" "No," Skellsgard said. "Ordinarily it could, but not with the way the link is now. The existing routines aren't designed to cope with the changing geometry. We uploaded patches before we sent it out, but the robot had to do a certain amount of hands-on piloting to get the ship to you in one piece."

"No problem, then. Just get the robot to do the same thing on the return leg." "There won't be a robot," Skellsgard said, wondering whether pain and blood-loss were affecting Auger's short-term memory. "Even if you hadn't volunteered it to protect your detective, we'd need it to stay behind at the E2 end to stabilise the throat and ramp down the power after insertion. You remember how tricky it was to send me back without the throat collapsing catastrophically?"

"Yes," Auger said.

"Well, it'll be twenty times more difficult now, and there isn't anyone warm to stay behind to manage the throat contraction. That's what we need the robot for."

"d.a.m.n," Auger said.

"If we could have squeezed two robots in, we'd have sent two. I was kind of hoping you'd be sharp

enough to fly her back."

"I think I'm going to be a little woozy," Auger said. "The robot talked about pumping me full of UR."

"If the robot says you need UR, I'd trust the robot."

"Absolutely, but I might not be conscious the whole way back."

"In that case," Skellsgard said, "we have ourselves a problem."

"Not necessarily," Floyd said.

Auger looked at him. The faces on the screens looked at him, in perfect unison. Even the robot glanced

at him, its blank sphere of a head somehow managing to evince polite scepticism.

"You got something to contribute?" Skellsgard said.

"If Auger can't fly the ship, then I'll have to."

"You have no idea what's involved. Even if you did...s.h.i.t, man, you don't know a wormhole from your b.u.t.thole."

"No, but I can learn." Floyd directed his attention at the nearest floating image.

"Fine," Skellsgard said. "You can begin by telling me what you already know about matter/exotic matter coupling parities, and we'll go from there. I take it you do have some pa.s.sing familiarity with the basic principles of pseudo-wormhole engineering? Or am I going too fast for you?"

"I can change a spark plug," Floyd said.

Auger let out a small, pained yelp.

"I am going to administer a local anaesthetic," the robot said. "There may be some temporary loss of mental clarity."

"Bring it on," she said.

TWENTY-SEVEN.

When the snake robot had patched her up, it carried Auger into the pa.s.senger compartment of the battered ship. Floyd was already inside, strapped into the rightmost of the three chairs, carrying on his conversation with Skellsgard. Inside, the ship did at least look new, despite its external appearance. The seats were heavy affairs of padded black material, with enormous cross-webbed buckles and head restraints. In front of each seat, folded aside until the occupant was in place, was a complicated arrangement of controls and screens, markedly more bulky and robust than anything Floyd had seen so far. There were very small windows surrounded by yet more banks of controls, lights and screens. Behind the padded seats was a very narrow companionway leading-as far as Floyd could tell-to a set of storage lockers adjacent to a washroom about the size of a small kennel, with an even smaller kitchen/ medical cubicle next to it. He knew it was a medical cubicle because of the Red Cross symbol on one of the white equipment boxes bolted to the wall. The rest of the ship was not accessible from the pa.s.senger compartment, and must have been taken up with machinery and fuel, or whatever else it needed to function. Pumps and generators chugged and hummed, and occasionally there was a thump or whine from some hidden mechanism.

"How much has Auger told you?" Skellsgard said.

"d.a.m.n little."

"Where did she tell you this ship was going to take her?"

"She didn't," Floyd said.

"Huh." This seemed to amuse the other woman no end. "So what's your best guess?"

"My best guess is that we're going to take a trip down some kind of underground tunnel. Maybe we'll

come out in the Atlantic and make the rest of the trip by submarine. Or maybe we'll be met by a squadron of flying pigs."

"Something tells me you have doubts."

"Call me a stickler for detail," Floyd said, "but I couldn't help noticing you mention something about Earth and Mars back there."

"Those were codewords, you silly boy."

"They'd have to be," Floyd said.

"All right. Listen up, and listen good. This is what you absolutely need to know, if Auger can't make

herself useful. You're going to be in this thing for thirty hours, give or take. It's going to be rough. How rough will depend on luck and the robot getting you off to a good start. But if I were you, I wouldn't take too many trips to the head."

"I have a weak bladder."

"Tell Floyd about the manual controls," Auger said as the robot eased her into the left-hand couch, contorting its body to reach inside the ship.

"Floyd," Skellsgard said, "I want you to fold down the console panel in front of your seat, so that it's

across your lap. Then latch it in place."

"Done," Floyd said.

"Get your hand around the joystick. Squeeze it. The display to your right should show a green-on-red

stress-energy grid. Got that?"

Floyd did as he was told. "I'm seeing a grid," he said. "I'm also seeing a lot more than that."

"That's fine. Now, do you see the blue diamond-shaped marker, between the two yellow brackets?"

"I'm seeing several diamonds."

"Move the joystick laterally. The icon that moves is the one you need to worry about. Ignore the fixed markers for now, and don't worry about all them teeny little numbers."

"The grid is changing. It's like it's drawn on hot toffee, and I'm dragging a spoon through it."

"That's the idea. Now flip up the red cover on the back of the joystick and get your thumb on the right pressure pad. The right, not the left. Squeeze it gently and tell me what happens to the grid."

"The grid's moving. Everything's moving, drifting to the left."

"That's expected. What you're seeing is a visual representation of the tunnel geometry ahead of the ship, approximately a light-microsecond downstream from the throat. The system is showing you a prediction of your drift based on that geometry." Floyd opened his mouth to speak, but Skellsgard was ahead of him. "Don't worry your pretty little head about the details. The key thing is that the geometry isn't stable, and if we let the ship fly itself, it'll keep nosing to one side of the tunnel or the other. You don't want that to happen, since the tidal stresses become exponentially stronger the closer to the sides you get. Now, the ship's guidance spines can absorb glancing impacts with the tunnel walls, but the telemetry I'm seeing at this end tells me that those spines took quite a pounding on the way over. Hull armour looks pretty crumpled as well."

"The telemetry's right," Auger said. "I'm not sure the ship will hold together, even without additional stresses."

"We'll have our fingers crossed at this end. In fact, we'll have everything crossed." Resigned to the inevitable, perhaps, Skellsgard's voice suddenly became hushed and businesslike. "The important thing is that the uploaded software patches should do a pretty good job even with the changing geometry, so you won't have to fly the ship all the way home."

"That sounds good," Floyd said. "I don't think I could manage to do it for thirty hours straight."

"But you'll still have to override the autopilot now and then. The simulations we've run at this end show that the guidance system doesn't cope well with abrupt changes in tunnel geometry, especially when the shear angles exceed seven hundred and twenty degrees."

"Doesn't cope well?" Floyd asked.

"It crashes."

"The ship crashes?"

"The software."