"Six hundred and ten hours ago," said a familiar contralto. "Watch."

  The view zoomed on the three objects. Lens-shaped spacecraft, big. Kzinti design, Louis thought. They stopped just above the peak, then began their descent, two or three meters above the glassy crater wall.

  "The warcraft are moving quite slowly. Let me show you fast-forward," the Hindmost said. The warcraft moved briskly downslope. Beyond and below, cloudscape jumped into streamlined motion. "In two hours, twenty minutes at just under sonic speed, they had covered fourteen hundred miles. For kzinti, amazing restraint. Then they diverged, thus --"

  The cloudscape and the saucers jerked to a near stop. Two veered off at right angles; the third continued straight on.

  White light blinked. Then the scene was as before, but the three ships had a blobby, half-melted look, and they gleamed like mirrors. They began to descend ... to fall.

  "Stasis fields. They stopped your beam," Louis said.

  "Worrisome, Louis. Wrong twice within five seconds. Is your brain deteriorating?"

  "That can happen," Louis said equably.

  The Hindmost said, "Those beams were intense. Vast energy flux was trapped inside the stasis fields before they formed."

  "But --"

  "You and Nessus survived a similar attack because *we* design defense mechanisms to react *quickly*! Those kzinti warcraft are nothing but bombs now. And that was the Ringworld Meteor Defense, but I did not use it."

  "Yeah, right."

  "Observe." The view jumped ... a view of the magnified sun, darkened to something tolerable. From the fluid storm a plume rose in fast-forward motion. Higher, straight toward the camera ... hundreds of thousands of miles. A brighter shock wave was rising from its base. It lashed out along the plume and was suddenly terribly bright.

  "A superthermal laser effect, definitely the Ringworld Meteor Defense, Louis. But not mine."

  The Hindmost *would* lie. But would he shoot down an invading ship?

  "Louis, I'm not shooting down invading spacecraft! I want to contact them. A hyperdrive motor could free me from this place!"

  "I buy that, I guess, but -- Hindmost, do you think someone is in the RepairCenter with you?"

  "I do not believe my defenses have been breached. Louis, there are two Great Oceans."

  It took Louis a moment to see what the Hindmost meant.

  A single GreatOcean would unbalance the Ringworld. The water involved would mass as much as a major Jovian moon. There had to be two, on opposite arcs; and there were.

  The Hindmost's crew had found a RepairCenter in one GreatOcean, under the Map of Mars. The other ocean they had never explored at all.

  And it was across the Ringworld's diameter. The Ringworld was sixteen light-minutes across. Sixteen minutes at lightspeed before a second RepairCenter could *see* invading ships coming through Fist-of-God. Eight minutes more to begin to affect the sun. More time -- an hour? Two? -- to stretch a plume of plasma some millions of miles out from the sun, then cause it to lase. The terrible sword of light would be another eight minutes on its way.

  Two hours and twenty minutes was a plausible guess. Louis said, "Stet. You'd best assume there's another RepairCenter on the far side of the Ringworld Arch, and a protector inside."

  "Why a protector? Mind you, Louis, I think so, too."

  "A protector would find a way in. If a hominid got in somehow -- a breeder -- he'll be a protector by now. The other RepairCenter must be infested with tree-of-life, like ours was. Is this what you wanted me for? You know almost as much about protectors as I do, and it's dead of night here, so my brain may not be fully functional."

  "Age, too, may have affected your brain. We do need to talk, and I have more to show you. Louis, shall I appear to the Weavers and acknowledge your power? Or shall I not?"

  "Thoughtful of you, but that may be out of our hands." The locals slept, but Fishers or Sailors must have seen this glare, and who could know when a Ghoul was nearby?

  *Actually* ...

  The Hindmost missed Louis's sudden grin. He said, "These Weavers seem hospitable."

  "Every species around the GreatOcean is friendly if you watch your mouth."

  "What news of our companions?"

  "Chmeee took an assault vehicle to carry his gear. Didn't you have a webeye on that?"

  "He buried it," the Hindmost said.

  Louis laughed.

  "He can unearth it if he has need. What of the City Builders?"

  Louis said, "Kawaresksenjajok and Harkabeeparolyn had two children to raise and another on the way. I won't say we were bored with each other, but ... futz. I put them off at a village downstream from here, with one of the assault boats. They're teaching there and along the far shore. How are you?"

  "Not presentable. Louis --" Three silver blobs bouncing down the slope of Fist-of-God were replaced by a glare of snow, a mountain ridge in broad daylight. A green outline blinked around two dots crawling through a cleft in the ridge. "-- let me direct your attention to these. Ten years ago I showed you --"

  "I remember. Is this the same view?"

  "Yes, as of three days ago, taken from the rim of a floating structure above a vampire nest."

  "Is this what you've been showing the Weavers?"

  "Yes." The view zoomed. Those were great crude six-wheeled vehicles, possibly powered by steam. One of them was turning back, upslope. The view zoomed on the other, on the driving bench. "These are Machine People?"

  Louis looked. "Right. Note the beards. Looks like Machine People vehicles, too. Hey ..."

  "Louis, my computer's recognition program --"

  "That's Valavirgillin!"

  Chapter 6 -

  Snowrunner's Pass

  The Barrier of Flame had been given a low, eroded look.

  None but Valavirgillin would see mountains that way. Louis Wu of the Ball People had taught her to view the world as a mask. He and his weird companions had looked up into its black underside, where seas were bulges, mountain ranges were chains of pits, and tremendous pipes carried seabottom flup under the world and over the rim wall to become spill mountains.

  Some entity had *carved* the Barrier of Flame to suit esthetic whims. Had carved passes through the range for the convenience of travelers. Various Red tribes and their herds had followed the retreating mirror-flowers across Snowrunner's Pass. Two of these same Reds now guided the cruisers.

  Night was biting an edge from the sun as the cruisers crossed the crest of Snowrunner's Pass. None of them had seen blue sky in many falans. They gloried in it. Unbroken clouds spread below them. There was snow on the ground, not deep but enough to cause the wheels to slide. Vala had trouble steering. To left and right the mountains flamed, raw sunlight reflecting from snowfields.

  Below and behind the driving bench, Waast was telling someone unseen, "We didn't see snow when we crossed here. The mirror-flowers burned it all away."

  Her bulk had half hidden Tegger. He said, "Mirror-flowers don't like clouds. They burn anything that moves. Waast, is it good to separate the wagons this late in the day?"

  "One must decide," Waast said firmly.

  The Red Herder frowned. "Of course the pilot gives the orders. But, look you, mates have been separated. Valavirgillin and Kaywerbrimmis. Grieving Tube and Harpster, too. Kaywerbrimmis and Chitakumishad are both *male*. What if vampires come? Warvia and I are safe separated. Beedj is with you, Paroom is with Twuk, Manack is with Coriack, but what of the rest?"

  Vala steered Cruiser One down the long slope, pretending not to listen. This was how a Red Herder expressed his dissent, by letting it be overheard. *Mates!* The next turn put her in sight of a wide brown river.

  The Reds were of a
monogamous race, and mated. They didn't like being separated; but two cruisers need two guides. Kay and Vala must part too: two cruisers need two drivers. But she and Kaywerbrimmis were not mated!

  And here came Pilack pelting after her ahead of Cruiser Two. Vala choked the fuel line and let her cruiser stop.

  Gleaners could run like the wind. Pilack looked up at her, grinning, for a moment in which to catch his breath. He said, "Kaywerbrimmis wants to go farther up."

  She looked back. Left of the pass the crest rose gently enough. Kay would be above the snow line, and he'd have a view.

  "Shall we wait?"

  "Kay says don't wait. Stop the cruiser if you find danger. We'll have you in view. We'll come."

  Pilack ran away. Uphill, Kay's crew were offloading cargo. Tons of it. Without Paroom and Twuk, it would have taken forever. A few tenbreaths later Cruiser Two was in motion, with Kay on the steering bench and the rest of the crew walking behind, except for the Ghoul, of course. Grieving Tube would not wake till halfnight.

  Now a curve took them out of sight.

  Cruiser One carried Valavirgillin and Sabarokaresh, Waast and Beedj, Manack and Coriack, Tegger, and Harpster. They stayed out of the payload shell. The payload shell had never been so clean, so scentless. The Ghoul Harpster would have liked the darkness; but he made do with the rest taking their turns under the awnings, on blankets spread along the running boards.

  The Machine People on Cruiser Two were both male. She and Kay had dithered about taking Chitakumishad. They'd have preferred Spash, but nobody would risk Spash's life while she was pregnant. And Chit had had to be tied up during the vampire attack, but he was clever and skillful with tools.

  They'd be all right. There was always rishathra.

  Cruiser One was beneath the cloud deck now. The darkening day signaled a sun half shadowed. And what was happening down there at the river? "Tegger, give me your sight. The river?"

  Gleaners were nearsighted; they could barely see beyond their toes. Machine People had good eyes. But none had eyes like the Reds. Tegger scrambled up onto the steering bench, peered under his hand; then climbed to the cannon tower, higher yet.

  "Vampire. Two of them. They're hideous, Vala. Do you hear anything?"

  "No."

  "I think they're singing, Vala. And ... a black thing is coming out of the water. What do River People look like?"

  "Wet black. Your size, but compact, streamlined --"

  "Short arms and big hands with webbed fingers? Legs likewise? They've lured one out. Now one vampire is moving downstream. Wrong gender, maybe, I can't tell from this far away. How fast can we get down?"

  "Not that fast." Not fast enough for rescue. They were closer now. Vala could see two pale shapes and a black. One pale shape ambled away down the shore. The black waddled to the other white, who enfolded it in its arms. Moments later the white hurled itself backward onto the mud.

  The squat black shape approached again, arms outstretched. The white backed away fast on its skinny buttocks. Recovered its courage, or its hunger; got up and accepted the other's embrace.

  Black rubbed against white. Vala heard a squall like a mountain cat's as the pale shape tore itself free and ran away along the shore, upstream.

  The black shape couldn't catch up. It stopped and cried, a desolate honk.

  "How fast?" Tegger asked again.

  "We'll be down before halfnight, in time to wash. Then we'll test our defenses, I think. Best if Cruiser Two stays high. Manack, you listening? Coriack?"

  "I hear," Coriack said. "Cruiser Two stays high till dawn."

  "Go tell Kaywerbrimmis. Then stay with Cruiser Two! I don't want you alone on the slopes when night falls."

  Beedj was up and walking ahead and to the right, his crossbow cocked. Barok was tending the cannon. Tegger perched above him.

  The black hominid lay inconsolable on wet river mud. It presently rolled over and saw the descending cruiser. It waited.

  Manack dropped from the running board and ran ahead. Vala's gun was in her hands, ready.

  A vampire sang.

  The music was unmistakable, thrilling along her nerves. Manack came to a jarring stop. Vala could see no target. The River Person waddled toward the bushes.

  The second vampire stepped timidly out to meet it. Male, it was. It raised its arms imploringly. With the scent and the music going wild in her head, Vala fired.

  The bullet struck beneath its armpit, slamming the vampire violently away. In the near-dark its blood was as red as any hominid's. Vala caught a stronger whiff of its scent; she raised the towel and inhaled pepperleek.

  Manack was hanging back. The River Person cast itself on the body. The vampire spasmed in agony, then relaxed.

  Vala pulled the cruiser alongside both. Passengers were dropping from the running board.

  Slick black hair, short thick arms and legs, wide hands and feet, streamlined body ... clothing. The River Woman's torso was covered with some other creature's brown fur. She looked up, then pulled away from the vampire male with visible effort.

  "Greeting,"' she said. "I am Wurblychoog --" a liquid flow of syllables and a trace of smile. *You can't pronounce that.*

  Vala said, "Greetings, Wurble. Valavirgillin. Why didn't the vampire kill you?"

  "This," the woman said, and her hands waved down her barrel body. The garment was stiff around her throat. The sides were smooth leather, the hair shaved off. The rest, chest and back, were fur taken from some water beast.

  She said, "We take a jell from a floating predator in LakeDeeps, half a daywalk across land. The jellfisher stings fish to eat them. The sting is in the jell. We smear an otter fur vest with jell, then shave off the fur where our arms lie when we swim. Vampires don't like the sting, but after, must ... must ..." She turned to Manack. "Can swim, little courageous one? Can hold breath for a little while?"

  "I would drown," said Manack.

  The River Woman told Vala, "Homeflow tribe has only four vests. Vampires bar us from shore, many falans now. If from time to time one of us wears a vest and lets a vampire embrace her, she may teach them to leave River People alone. Then we can hunt the shore for a time."

  "You show great courage."

  "I show my courage for Borubble, to take him for my mate."

  "And get some vampire scent on yourself, too," Waast leered.

  "Shubble flup! This is not to speak of. You, red one, can dive deep for only a few tens of breaths?"

  Tegger shook his head. He was tired of the question. The River Woman sighed. "We hear rishathra. Never practice. Must mate! Will tell Borubble the good news. Will tell him visitors come, too. Stay here on mud flat, see vampires coming from a long way."

  She was across the mud and into the water before Vala could frame an intelligent reply.

  Water could hide threats other than vampires. The whole team bathed with edged weapons in hand. Afterward Barok went upstream with the Gleaners to fish. Vala envied him a little, but she must remain to set up defenses.

  Cruiser One spent the night on the mud flat. No visitors came, vampires or River People.

  It was all going very smoothly, Vala thought. Very much according to prediction and plan. That worried her.

  ***

  Three nights ago they had put a final shape to their plans.

  Four Reds had come to the war. Warvia and Tegger had stayed, but two unmated males, Anakrin hooki-Whanhurhur and Chaychind hooki-Karashk, had been persuaded to return to Red territory carrying instructions that might be the saving of them all. Whand had had enough of vampires, and it seemed he and Spash had gotten pregnant. They would stay to refuel Cruiser Three. That left Valavirgillin and Kaywerbrimmis, the remaining drivers, split up to c
ommand two cruisers.

  They'd chosen the teams early, then argued about it every night since.

  Raking through a mountainous Grass Giant midden for several days had not improved the Machine People's standing with these tribes. Vala was sure of that. But Grass Giant dung had yielded many barrels of saltpeter crystals.

  The relief map outside the wall had become elaborate and wonderful. Only at halfnight and halfday was there light for Ghouls and the other species to work together on it; but they'd had a falan, seventy-five days, to do that. Dirt was replaced with colored clays. Once witnesses agreed on the shape of the land, they'd baked it hard under coals, and afterward used colored sand to mark possible routes for the cruisers. They were still moving those lines when night fell, and all retreated inside.

  The vampires didn't come every night, but they came in swarms.

  Vampires didn't learn, didn't communicate. Moonwa had mounted the Marsh People's curved window in the starboard-spin curve of the wall. The vampires attacked from starboard-spin, and warriors of four species killed them with guns and crossbows, firing around the edge of an invisible shield.

  Vala had learned crossbows that way, several nights running. She loved the false sense of invulnerability ... false, because the window would not stop vampire scent.

  ***

  The main building was a near-dome, fabric stretched over the top of a dirt wall, with a central pole. It was awesomely big, but awesomely crowded. Fifteen hundred Grass Giants -- more women than men, a great many children, infants everywhere -- made a stench rich enough to slice with a scythe-sword.

  Wemb was in a cluster of wives. They were feeding her by hand, feeding themselves, too, and Wemb seemed to be enjoying it. Barok waved at her, and she waved back without getting up. Recovering nicely, Vala thought, from the night she and Barok had spent down among the vampires.

  Barok would ride with Cruiser One. Vala had wondered if he would drop out of the game with Whand and Spash, or chase down the vampires who had taken his daughter.

  Grass Giants were big, but they could stand crowding. For Machine People, Vala discovered, the problem was to avoid getting stepped on.