"... the dark of space—"

  "Thorvald!" Shann skidded in the sand, went down on his knees. The manner of their last parting was forgotten as he took in the officer's condition.

  The other did not stop his swaying, but his head turned with a stiff jerk, the gray eyes making a visible effort to focus on Shann. Then some of the strain smoothed out of the gaunt features and Thorvald laughed softly.

  "Garth!"

  Shann stiffened but had no chance to protest that mistaken identification as the other continued: "So you made class one status, boy! I always knew you could if you'd work for it. A couple of black marks on your record, sure. But those can be rubbed out, boy, when you're willing to try. Thorvalds always have been Survey. Our father would have been proud."

  Thorvald's voice flattened, his smile faded, there was a growing spark of some emotion in those gray eyes. Unexpectedly, he hurled himself forward, his hands clawing for Shann's throat. He bore the younger man down under him to the sand where Lantee found himself fighting desperately for his life against a man who could only be mad.

  Shann used a trick learned on the Dumps, and his opponent doubled up with a gasp of agony to let the younger man break free. He planted a knee on the small of Thorvald's back, digging the officer into the sand, pinning down his arms in spite of the other's struggles. Regaining his own breath in gulps, Shann tried to appeal to some spark of reason in the other.

  "Thorvald! This is Lantee—Lantee——" His name echoed in the mist-walled void like an unhuman wail.

  "Lantee——? No, Throg! Lantee—Throg—killed my brother!"

  Sand puffed out with the breath, which expelled that indictment. But Thorvald no longer fought, and Shann believed him close to collapse.

  Shann relaxed his hold, rolling the other man over. Thorvald obeyed his pull limply, lying face upward, sand in his hair and eyebrows, crusting his slack lips. The younger man brushed the dirt away gently as the other opened his eyes to regard Shann with his old impersonal stare.

  "You're alive," Thorvald stated bleakly. "Garth's dead. You ought to be dead too."

  Shann drew back, rubbed sand from his hands, his concern dampened by the other's patent hostility. Only that angry accusation vanished in a blink of those gray eyes. Then there was a warmer recognition in Thorvald's expression.

  "Lantee!" The younger man might just have come into sight. "What are you doing here?"

  Shann tightened his belt. "Just about what you are." He was still aloof, giving no acknowledgment of difference in rank now. "Running around in this fog hunting the way out."

  Thorvald sat up, surveying the billowing walls of the hole which contained them. Then he reached out a hand to draw fingers down Shann's forearm.

  "You are real," he observed simply, and his voice was warm, welcoming.

  "Don't bet on it," Shann snapped. "The unreal can be mighty real—here." His hand went up to the smarting brand on his shoulder.

  Thorvald nodded. "Masters of illusion," he murmured.

  "Mistresses," Shann corrected. "This place is run by a gang of pretty smart witches."

  "Witches? You've seen them? Where? And what—who are they?" Thorvald pounced with a return of his old-time sharpness.

  "They're females right enough, and they can make the impossible happen. I'd say that classifies them as witches. One of them tried to take me over back on the island. I set a trap and caught her; then somehow she transported me——" Swiftly he outlined the chain of events leading from his sudden awakening in the river tunnel to his present penetration of this fog-world.

  Thorvald listened eagerly. When the story was finished, he rubbed his hands across his drawn face, smearing away the last of the sand. "At least you have some idea of who they are and a suggestion of how you got here. I don't remember that much about my own arrival. As far as I can remember I went to sleep on the Island and woke up here!"

  Shann studied him and knew that Thorvald was telling the truth. He could remember nothing of his departure in the outrigger, the way he had fought Shann in the lagoon. The Survey officer must have been under the control of the Warlockians then. Quickly he gave the older man his version of the other's actions in the outer world and Thorvald was clearly astounded, though he did not question the facts Shann presented.

  "They just took me!" Thorvald said in a husky half whisper. "But why? And why are we here? Is this a prison?"

  Shann shook his head. "I think all this"—a wave of his hand encompassed the green wall, what lay beyond it, and in it—"is a test of some kind. This dream business.... A little while ago I got to thinking that I wasn't here at all, that I might be dreaming it all. Then I met you."

  Thorvald understood. "Yes, but this could be a dream meeting. How can we tell?" He hesitated, almost diffidently, before he asked: "Have you met anyone else here?"

  "Yes." Shann had no desire to go into that.

  "People out of your past life?"

  "Yes." Again he did not elaborate.

  "So did I." Thorvald's expression was bleak; his encounters in the fog must have proved no more pleasant than Shann's. "That suggests that we do trigger the hallucinations ourselves. But maybe we can really lick it now."

  "How?"

  "Well, if these phantoms are born of our memories there are about only two or three we could see together—maybe a Throg on the rampage, or that hound we left back in the mountains. And if we do sight anything like that, we'll know what it is. On the other hand, if we stick together and one of us sees something that the other can't ... well, that fact alone will explode the ghost."

  There was sense in what he said. Shann aided the officer to his feet.

  "I must be a better subject for their experiments than you," the older man remarked ruefully. "They took me over completely at the first."

  "You were carrying that disk," Shann pointed out. "Maybe that acted as a focusing lens for whatever power they use to make us play trained animals."

  "Could be!" Thorvald brought out the cloth-wrapped bone coin. "I still have it." But he made no move to pull off the bit of rag about it. "Now"—he gazed at the wall of green—"which way?"

  Shann shrugged. Long ago he had lost any idea of keeping a straight course through the murk. He might have turned around any number of times since he first walked blindly into this place. Then he pointed to the packet Thorvald held.

  "Why not flip that?" he asked. "Heads, we go that way—" he indicated the direction in which they were facing—"tails, we do a rightabout-face."

  There was an answering grin on Thorvald's lips. "As good a guide as any we're likely to find here. We'll do it." He pulled away the twist of cloth and with a swift snap, reminiscent of that used by the Warlockian witch to empty the bowl of sticks, he tossed the disk into the air.

  It spun, whirled, but—to their open-jawed amazement—it did not fall to the sand. Instead it spun until it looked like a small globe instead of a disk. And it lost its dead white for a glow of green. When that glow became dazzling for Terran eyes the miniature sun swung out, not in orbit but in straight line of flight, heading to their right.

  With a muffled cry, Thorvald started in pursuit, Shann running beside him. They were in a tunnel of the fog now, and the pace set by the spinning coin was swift. The Terrans continued to follow it at the best pace they could summon, having no idea of where they were headed, but each with the hope that they finally did have a guide to lead them through this place of confusion and into a sane world where they could face on more equal terms those who had sent them there.

  14. ESCAPE

  "Something ahead!" Thorvald did not slacken the pace set by the brilliant spot of green they trailed. Both of the Terrans feared to fall behind, to lose touch with that guide. Their belief that somehow the traveling disk would bring them to the end of the mist and its attendant illusions had grown firmer with every foot of ground they traversed.

  A dark, fixed point, now partly veiled by mist, lay beyond, and it was toward that looming half-shadow that the
spinning disk hurtled. Now the mist curled away to display its bulk—larger, blacker and four or five times Thorvald's height. Both men stopped short, for the disk no longer played pathfinder. It still whirled on its axis in the air, faster and faster, until it appeared to be throwing off sparks, but the sparks faded against a monolith of dark rock unlike the native stone they had seen elsewhere. For it was neither red nor warmly brown, but a dull, dead black. It could have been a huge stone slab, trimmed, smoothed, set up on end as a monument or marker, except that only infinite labor could have accomplished such a task, and there was no valid reason for such toil as far as the Terrans could perceive.

  "This is it." Thorvald moved closer.

  By the disk's action, they deduced that their guide had drawn them to this featureless black steel with the precision of a beam-controlled ship. However, the purpose still eluded them. They had hoped for some exit from the territory of the veil, but now they faced a solid slab of dark stone, neither a conventional exit or entrance, as they proved by circling its base. Beneath their boots was the eternal sand, around them the fog.

  "Now what?" Shann asked. They had made their trip about the slab and were back again where the disk whirled with unceasing vigor in a shower of emerald sparks.

  Thorvald shook his head, scanning the rock face before them glumly. The eagerness had gone out of his expression, a vast weariness replacing it.

  "There must have been some purpose in coming here," he replied, but his tone had lost the assurance of moments earlier.

  "Well, if we strike away from here, we'll just get right back in again." Shann waved a hand toward the mist, waiting as if with a hunter's watch upon them. "And we certainly can't go down." He dug a boot toe into the sand to demonstrate the folly of that. "So, what about up?"

  He ducked under the spinning disk to lay his hands against the surface of the giant slab. And in so doing he made a discovery, revealed to his touch although hidden from sight. For his fingers, running aimlessly across the cold, slightly uneven surface of the stone, slipped into a hollow, quite a deep hollow.

  Excited, half fearing that his sudden guess might be wrong, Shann slid his hand higher in line with that hollow, to discover a second. The first had been level with his chest, the second perhaps eighteen inches or so above. He jumped, to draw his fingers down the rock, with damage to his nails but getting his proof. There was a third niche, deep enough to hold more than just the toe of a boot, and a fourth above that....

  "We've a ladder of sorts here," he reported. Without waiting for any answer from Thorvald, Shann began to climb. The holds were so well matched in shape and size that he was sure they could not be natural; they had been bored there for use—the use to which he was now putting them—a ladder to the top of the slab. Though what he might find there was beyond his power to imagine.

  The disk did not rise. Shann passed that core of light, climbing above it into the greater gloom. But the holes did not fail him; each was waiting in a direct line with its companion. And to an active man the scramble was not difficult. He reached the summit, glanced around, and made a quick grab for a secure handhold.

  Waiting for him was no level platform such as he had confidently expected to find. The surface up which he had just made his way fly-fashion was the outer wall of a well or chimney. He looked down now into a pit where black nothingness began within a yard of the top, for the radiance of the mist did not penetrate far into that descent.

  Shann fought an attack of giddiness. It would be very easy to lose control, to tumble over and be swallowed up in what might well be a bottomless chasm. And what was the purpose of this well? Was it a trap to entice a prisoner into an unwary climb and then let gravity drag him over? The whole setup was meaningless. Perhaps meaningless only to him, Shann conceded, with a flash of level thinking. The situation could be quite different as far as the natives were concerned. This structure did have a reason, or it would never have been erected in the first place.

  "What's the matter?" Thorvald's voice was rough with impatience.

  "This thing's a well." Shann edged about a fraction to call back. "The inside is open and—as far as I can tell—goes clear to the planet's core."

  "Ladder on the inside too?"

  Shann squirmed. That was, of course, a very obvious supposition. He kept a tight hold with his left hand, and with the other, he did some exploring. Yes, here was a hollow right enough, twin to those on the outside. But to swing over that narrow edge of safety and begin a descent into the black of the well was far harder than any action he had taken since the morning the Throgs had raided the camp. The green mist could hold no terrors greater than those with which his imagination peopled the depths now waiting to engulf him. But Shann swung over, fitted his boot into the first hollow, and started down.

  The only encouragement he gained during that nightmare ordeal was that those holes were regularly spaced. But somehow his confidence did not feed on that fact. There always remained the nagging fear that when he searched for the next it would not be there and he would cling to his perch lacking the needful strength in aching arms and legs to reclimb the inside ladder.

  He was fast losing that sense of well being which had been his during his travels through the fog; a fatigue tugged at his arms and weighed leaden on his shoulders. Mechanically he prospected for the next hold, and then the next. Above, the oblong of half-light grew smaller and smaller, sometimes half blotted out by the movements of Thorvald's body as the other followed him down that interior way.

  How far was down? Shann giggled lightheadedly at the humor of that, or what seemed to be humor at the moment. He was certain that they were now below the level of the sand floor outside the slab. And yet no end had come to the well hollow.

  No break of light down here; he might have been sightless. But just as the blind develop an extra perceptive sense of unseen obstacles, so did Shann now find that he was aware of a change in the nature of the space about him. His weary arms and legs held him against the solidity of a wall, yet the impression that there was no longer another wall at his back grew stronger with every niche which swung him downward. And he was as sure as if he could see it, that he was now in a wide-open space, another cavern; perhaps, but this one totally dark.

  Deprived of sight, he relied upon his ears. And there was a sound, faint, distorted perhaps by the acoustics of this place, but keeping up a continuous murmur. Water! Not the wash of waves with their persistent beat, but rather the rippling of a running stream. Water must lie below!

  And just as his weariness had grown with his leaving behind the fog, so now did both hunger and thirst gnaw at Shann, all the sharper for the delay. The Terran wanted to reach that water, could picture it in his mind, putting away the possibility—the probability—that it might be sea-born and salt, and so unfit to drink.

  The upper opening to the cavern of the fog was now so far above him that he had to strain to see it. And that warmth which had been there was gone. A dank chill wrapped him here, dampened the holds to which he clung until he was afraid of slipping. While the murmur of the water grew louder, until its slap-slap sounded within arms' distance. His boot toe skidded from a niche. Shann fought to hold on with numbed fingers. The other foot went. He swung by his hands, kicking vainly to regain a measure of footing.

  Then his arms could no longer support him, and he cried out as he fell. Water closed about him with an icy shock which for a moment paralyzed him. He flailed out, fighting the flood to get his head above the surface where he could gasp in precious gulps of air.

  There was a current here, a swiftly running one. Shann remembered the one which had carried him into that cavern in which the Warlockians had their strange dwelling. Although there were no clusters of crystals in this tunnel to supply him with light, the Terran began to nourish a faint hope that he was again in that same stream, that those light crystals would appear, and that he might eventually return to the starting point of this meaningless journey.

  So he strove only t
o keep his head above water. Hearing a splashing behind him, he called out: "Thorvald?"

  "Lantee?" The answer came back at once; the splashing grew louder as the other swam to catch up.

  Shann swallowed a mouthful of the water lapping against his chin. The taste was brackish, but not entirely salt, and though it stung his lips, the liquid relieved a measure of his thirst.

  Only no glowing crystals appeared to stud these walls, and Shann's hope that they were on their way to the cavern of the island faded. The current grew swifter, and he had to fight to keep his head above water, his tired body reacting sluggishly to commands.

  The murmur of the racing flood drummed louder in his ears, or was that sound the same? He could no longer be sure. Shann only knew that it was close to impossible to snatch the necessary breath as he was rolled over and over in the hurrying flood.

  In the end he was ejected into blazing, blinding light, into a suffocation of wild water as the bullet in an ancient Terran rifle might have been fired at no specific target. Gasping, beaten, more than half-drowned, Shann was pummeled by waves, literally driven up on a rocky surface which skinned his body cruelly. He lay there, his arms moving feebly until he contrived to raise himself in time to be wretchedly sick. Somehow he crawled on a few feet farther before he subsided again, blinded by the light, flinching from the heat of the rocks on which he lay, but unable to do more for himself.

  His first coherent thought was that his speculation concerning the reality of this experience was at last resolved. This could not possibly be an hallucination; at least this particular sequence of events was not. And he was still hazily considering that when a hand fell on his shoulder, fingers biting into his raw flesh.

  Shann snarled, rolled over on his side. Thorvald, water dripping from his rags—or rather steaming from them—his shaggy hair plastered to his skull, sat there.