the little machines rolled past within a few feet of thecrouching spider, hastening on with an uncanny pre-occupation.
Dworn saw that, like those he had seen earlier, they were of diversekinds; and several of them, fitted with claws and racks for transportingbooty, were heavily laden now with metal plates and girders carved fromsome larger machine, a roll of caterpillar tread, a slightly bentaxle.... The last pygmy in line, whose afterbody was a bloated tank,gurgled as it jolted by, and trailed an aroma of looted fuel.
A few yards beyond the staring watchers, each of the little plundererspivoted sharply in its turn and without even slackening speed vanishedstraight into the cliff-face. Dworn and Qanya looked incredulously atone another.
"A tunnel!" Dworn grunted in realization.
That explained one mystery, at least--how, if the winged and winglessstrangers' home base was somewhere above the cliffs, the wheeledmachines contrived to forage at the foot of the Barrier. They must haveone or more inclined tunnels, bored through solid rock for a distancethat staggered Dworn's imagination. Emerging at this level, they hadfound or constructed a passable road the rest of the way to the valleyfloor.... Now he noticed that the ledge to which the spider had solaboriously climbed showed signs of being an often-used trail, and thecliffs it skirted exhibited in places the raw marks of recent blasting.
"Remember this spot," he told Qanya. "If we should return this sameway--there's evidently an easier path down."
She said nothing. Dworn wondered wrily if, in her drug beclouded mind,she was aware of how unlikely it was that either of them would bereturning from beyond the Barrier.
A mad enterprise indeed--a ghost and a zombie, going to seek out a foewhose numbers and whose might grew ever more apparent. The tunnelopening here was clear evidence of engineering resources and skill farbeyond that of any of the machine races Dworn knew.
Its discovery was no help to them, since it was far too small to admitthe spider.
"Go on!" Dworn ordered doggedly. "At least we know now that _their_dwelling can't be far!"
Qanya glanced briefly sidelong at him, then moved the levers, and thespider rocked upright once more and began to climb.
* * * * *
The sun was low, and the shadows of rocks and dunes in the valley behindthem were pointing long blue fingers eastward, when the machinestaggered up the last precipitous ascent and stood on level ground atthe summit.
Dworn took a deep breath and looked ahead, looked for the first time inhis life upon the unknown land beyond the Barrier.
At first glance, it differed little from any of the desert country wherehe had lived all his life. The ground shelved gradually away from therocky rim on which they stood; far off, against the darkening easternsky, blue mountains rose murkily, but between here and the ranges lay avast shallow depression, an arid sink floored with wind-rippled sand.Perhaps it had been a lake-bed once, before natural or unnaturalcataclysms, and the millennial drying-up of all this country, hademptied it of water. Or perhaps--as its circular form suggested--it wasone of those other, mysterious depressions which were scatteredirregularly across the face of the earth where no lakes had ever been;those, legend said, were scars left by the ancients' wars.
The rich light of the declining sun fell at a shallow angle into themiles-wide bowl and brought out with startling clarity the maze ofwheel-tracks, crossing and criss-crossing, which covered its sandyexpanse and testified to a fever of recent machine activity there. Thelight gleamed, too, here and there, upon scurrying metallic shapes, thatraced by ones and twos or in trickling columns to and from the center ofthe bowl, where--
Dworn strained his eyes and his capacity for belief in an effort to makesense of the structures there, miles away. He was not very successful,for the scene was too unlike anything he had ever looked on before.
There were certain races which built stationary dwellings--Dworn knew ofthe scale-makers who lived, in colonies sometimes of considerable size,beneath individual armored, anchored domes sunk into the face of someimpregnable rock; he knew of the sand devils with their pits, and now hehad seen also how the spider people nested. But the huge buildings thatloomed yonder, lowering and windowless, and the winged things clusteringthick on the ground about them, were such as he had never seen in hisnomadic life.
Atop a slender tower that spired above the squat structures he couldmake out something which turned and turned, something like a broad netof lacy wires, revolving steadily from east to west, from north tosouth. Strange, too, the smooth-surfaced ways that radiated outward infour directions, like an immense cross, broad paved roads that came toabrupt dead ends a mile or more from the central buildings.... After amoment, though, he guessed that those were runways for the aircraftwhich flew from this place.
The unknown builders were obviously a mighty people, a people who hadperfected their peculiar form of organization on a gigantic scale. And apeople who acted and thought strangely; for their behavior, as Dworn hadobserved it, suggested a chilly-blooded and fanatic discipline, aregimentation which he found monstrous and repellent.
Dworn turned questioning eyes on Qanya.
"I don't know what they are," she answered his unspoken query in a voicethat faltered. "I remember this valley. But a few months ago it wasuninhabited. All this has been built since then."
* * * * *
Dworn hesitated. He was seeing very clearly now just how hopeless thismad expedition was. Nevertheless, he had sworn vengeance, and he couldat least perish with honor.
But--Seeing the fear in Qanya's face, it came to him sharply that, afterall, she had no part in his blood feud. She had served him well bybringing him this far. The vague plans he had had, of using thespider-machine for an attack on the enemy, stood revealed as rankestfolly. Big and powerful as the spider was by ordinary standards, againstsuch as those it could accomplish little more than a man with his barehands.
Which was what Dworn would be--He stifled further reflection, saidcrisply: "You can go now. I'll remain here; I have a duty to perform.But you can return--go make your peace with your people, or whatever youlike."
Qanya's black eyes met his squarely. "I won't," she said.
"Now see here--" Dworn began, and broke off, thunderstruck.
"B-but," he gulped, "you _can't_ disobey me. The drug, the spiderpoison--"
"Doesn't work on a born spider. I must have neglected to mention that,naturally, _we're_ all immunized against it." She smiled with a flash ofthose sharp white teeth.
"Then--then--" Dworn stumbled, feeling his preconceptions tossedhelter-skelter. "Then you must have come with me--of your own freewill!"
"At first," murmured Qanya, "I knew you'd never trust me unless Ipretended ... and I was curious, too, to see how it was to be the onethat obeyed. And then ... well, you'd have known, if you'd ever seen howthe drug really works. You should have realized, anyway, when I laughedat you.... But you do so love to be masterful don't you?"
For a moment, Dworn's chief emotion was one of quick rage at therevelation of how thoroughly she'd deceived him. Then the anger subsidedand left him feeling merely foolish, as he saw that she'd merely let himdeceive himself. And, finally--as it came home to him that this girl hadfollowed him of her own choice into exile and great danger--a new andquite unaccustomed feeling flooded in on him, a queer sense of humility.
"I'm sorry," he said confusedly. "I didn't--I don't--understand."
She breathed in a barely audible voice, "You said I was beautiful....And _you_ hadn't the drug."
From far away, from around the vast, mysterious buildings, came mournfulhooting sounds, a sighing and a sobbing as of some mythical monster intorment.
Dworn was rudely recalled to realization of where they were--and of thefact that, as the spider-machine stood poised here on the cliff-edge, itwould be starkly visible from over there, seen against the setting sun.
He gave up trying to unsnarl the tangle of his own feelings. He saidhurriedly, "But you s
hould go back. There's no time--I _have_ to go on.But there's no reason you should die."
Qanya's face was drawn and determined. "No," she said flatly.
"I don't know what you're talking about. But I won't leave you now...."
The distant sighing rose to a whining roar.
"Quick!" cried Dworn in desperation. "Find cover. I think we've beenseen!"
* * * * *
The girl reached for the controls and the spider's engine raced up. Butit was already late. Off yonder, along that one of the radiating runwaysthat stretched toward them, something was moving, racing swiftly andmore swiftly outward with its long shadow following it.
All at once the moving thing left its shadow behind, and