It was the lack of these substances that made Mach desperate and dangerous. The machine required them in order to develop its potential to reproduce its kind -- and some of them could be filtered from the bodies of the living spots. There was no inherent personal animus; Mach attacked because it was driven by a need that could not be denied, in much the fashion of Cub's need. Gradually, as it realized that the spots were in fact sentient, it came to equate destruction of them as long-range nonsurvival and tried to resist the urge to take what beckoned. But it could not.

Supply those substances, and Mach would no longer be an enemy. The machine might even cooperate with the other members of the enclave. Its strength on the physical level was such that it could be of substantial a.s.sistance to them -- especially in the effort to break out of the enclave.

OX had developed combat circuits to oppose the inimical behavior of the external patterns. Now he comprehended that patterns were ill equipped to indulge in such activities. Their intellectual comprehension translated only poorly into action. This was one reason the external patterns had done nothing but observe after arranging the enclave.

Machines, in contrast, were ent.i.ties of action. Mach's mind contained pragmatic instructions for accomplishing many tasks, provided the tools existed. OX now saw that he, as a pattern, had tools that the machine did not. Now OX understood enough, and he had a new sense of motivation. He made ready to act.

Chapter 15.

ALTERNITY.

They stood on a metal highway, and a tank was bearing down on them. It was a monster, with treads as high as a man and a nose needling forward like that of an atmosphere-penetrating rocket.

Veg's dizziness left him. He charged to the side. Tamme was right beside him, guiding his elbow in case he stumbled.

The tank careened on by, not swerving.

"Was that another trap?" Veg asked breathlessly.

"Coincidence, more likely. Do you recognize this alternate?"

He looked about. All around them were ramps and platforms, and on these structures vehicles of every size and shape sped by. Some were quite small, and some were tiny -- the size of mice, or even flies. But all were obviously machines.

"A bit like downtown Earth," he muttered. "But not -- " He paused. "The machine world! This is where they breed!"

"I doubt they breed," she said. "Nevertheless, this is a significant discovery."

"Significant! Those machines are half the problem! I had to fight one of them halfway across the desert to protect our supplies!"

"Only to fall prey to the sparkle-cloud," she reminded him.

"Yeah..."

A dog-sized machine headed for them. It had perceptor-antennae extending from the top, and it emitted a shrill beeping.

"We're discovered," Tamme said. "I think we'd better move on."

But it was already too late. The seemingly aimless paths of the machines suddenly became purposeful. From every side they converged.

"I think we'd better not resist," Tamme said. "Until we locate the projector, we're at a disadvantage."

They certainly were! They were now ringed by machines, several of which were truck-sized, and there was a dismaying a.s.sortment of rotating blades, pincers, and drills. But she had already noted a containment pattern to their activity rather than an attack pattern.

A container-machine moved up, and two buzz saws herded them into its cage. The mesh folded closed, and they were prisoners.

"You figure this is the end of the line?" Veg asked. "I mean, maybe the hexaflexagon goes on, but if the machines catch every visitor..."

"Uncertain," Tamme said. "Some may avoid capture, some may escape, some may be freed."

"How many agents do you figure are traveling around here?"

"It could be an infinite progression."

Veg was silent, chewing over that. She could read his concern: an endless chain of human beings parading through the worlds, right into the maw of the machine? That would explain how the machines knew so well how to handle them! And why the nose-woman on the fog world had not been surprised or afraid. The alternates would be like tourist stops...

They cruised up to a metal structure. "A machine-hive," Veg muttered, staring out through the mesh, and his description was apt. It rose hugely, bulging out over the landscape, and from every direction machines of all sizes approached, while others sped outward. The hum of their engines was constant and loud, like that of hornets. A number were flying machines, and these ranged from jet-plane to gnat size. They zoomed in and out of appropriately diametered holes.

Their own vehicle headed for one of the truck-sized apertures. The machine-hive loomed tremendously as they approached; it was a thousand feet high and as big around.

"Any way out, once we're in?" Veg asked apprehensively.

"I could short the gate mechanism and get us out of this vehicle," Tamme said. "But I don't think that would be expedient."

Veg looked out of the rushing landscape. They were now on a narrow, elevated railroad-trestle like abutment fifty feet above the metal ground. Small buzz-saw machines flanked them on trestles to either side, and a pincer-tank followed immediately behind. There was no clearance for pedestrians.

"We must be doing a hundred miles per hour," he remarked.

"More than that. The lack of proximate and stationary objects deceives the eye."

"Well, if the machines wanted to kill us, they'd have done it by now," he said. But he hardly bothered to conceal his nervousness.

So they stayed put. In moments their truck plunged into the tunnel -- and almost immediately stopped. Tamme, antic.i.p.ating this, caught Veg about the waist before he was flung into the wall. "Well, aren't we cozy," she murmured as she let him go.

"I wish you wouldn't do that," he muttered. He meant that she could have warned him instead of demonstrating her superior strength again -- and he also knew that she was aware of his reactions to contact with her body. She nodded to herself; she was in fact teasing him, probably trying to build up her own self-image in the face of her deterioration of set, of agent-orientation. This was a weak human device, and she would stop.

The gate opened. They stepped out. The gate closed, and the truck departed. But other bars were already in place, preventing them from following the vehicle out.

"Now we can make our break," Veg said. He put his hands on the bars and shook them. "Yow!"

Tamme knew what had happened. The metal was electrified. "They have had prior experience with our form of animation," she said. "Possibly the first agent escaped, but we shall not. We'll have to wait and see what they have in mind for us."

"Yeah," he agreed dubiously.

Tamme was already exploring their prison. It was brightly lit by glowing strips along the corners, the light reflecting back and forth across the polished metal walls. One wall had a series of k.n.o.bs and bulbs. They were obviously set up for human hands and perceptions. The machines would have no use for such things!

There was a pattern to the bank of k.n.o.bs. It resembled the controls to a computer. The k.n.o.bs would be to activate it, the lights to show what was happening.

"Very well," she murmured. She turned the end k.n.o.b quickly, removing her hand as it clicked over.

There was no shock. The light above that k.n.o.b brightened. Sound came from hidden speakers: raucous, jarring.

Tamme reversed the k.n.o.b. The sound died. "Alien juke box," Veg muttered.

"Close enough," Tamme agreed. She turned the next k.n.o.b.

Sound rose again: a series of double-noted twitterings, penetrating.

She turned that off and tried the third. This was like the roar of ocean surf, with a half-melodious variable foghorn in the background.