He kept moving. Behind him, circumspectly, Yanderman and Keefe followed, and then others of the Station community, their voices hushed as though they were afraid of waking a lurking monster, but commenting continually on the nature of the plants now revealed to view.

A hundred yards from the exterior, Conrad paused and turned his handlight upwards. Among the screening tangle of creepers it was just possible to pick out a huge curved structural member which might formerly have supported a walkway.

“We’ll have to get up there,” he whispered, copying without meaning to the hushed tones of his companions. “Can someone burn a way through the plants?”

Yanderman came up beside him, swinging his heatbeam to the ready. Just before activating it, he paused to ask, “You’re sure it won’t do any harm?”

“The cortex is over there,” Conrad said, pointing directly towards the centre of the dome. “Don’t ask how I know.”

Reassured, Yanderman activated the beam. A few seconds sufficed to crisp the trailing fronds into ash, and a sickly stench drifted up. Through wisps of smoke Conrad’s handlight shone on a spiral stairway leading upward.

It rang under his boots as he climbed.

Then the way was along the distorted back of the curved girder he had seen from the ground. All around, strange forgotten machines peered from swathes of strong-scented foliage; huge fungi in rainbow colours posed proudly on the ruins of man’s labour. Twice something slithered away from the inquiring beam of light, and Conrad shivered and had to force himself not to think of any danger other than that of the mounting power level in the cortex.

Down next, to a once-level platform a hundred yards square, where the heatbeam had to be used to clear a path a second time. Here there were metal frames, rust-pitted, that might have been furniture-flat tables, skeletal chairs, overturned in the course of the centuries by the feeble pull of the omnipresent creepers.

“We’re getting near,” he whispered. “I can feel it!”

“Then keep moving!” Yanderman rasped. “We can’t use the heatbeam indefinitely, you know!”

Conrad nodded and crossed the tilting floor of the platform to another winding stair at the other side. No, not a stair this time-a spiralling ramp which he half-expected to move as he stepped on it. But it would not have moved since the Station was switched to emergency power four and a half centuries ago.

The going was slippery with decaying vegetation now. Rather than exhaust the heatbeam here where there were no threatening seed-masses, Conrad called for hatchets and sticks to slash at the creepers. With agonising slowness they ascended the ramp.

“There,” he breathed when they reached the top, and flung out his arm.

Before them, discernible among the close-set creepers and fungi, was the upper surface of a huge once-shiny sphere, posed on a support which they could not see for leaves. In the beam of the handlight it still had a dull lustre, pitted now with centuries of corrosion. It was more than a man’s height in diameter. Once it had been protected by a curved glass superstructure, but the glass had fallen in shards long since and crunched under their feet as they approached.

“This?” Yanderman demanded.

Conrad gave a weary nod. “It’s inside the metal ball. Now all we have to do is locate the power controls and adjust them. There’s a switch, and it’s not far away. Everybody hunt around here!” he added, raising his voice and gesturing largely. “A switch-a red switch on a white board somewhere nearby!”

The others looked blankly about them.

“How are we going to find it in this tangle?” Keefe demanded of Conrad. “I take it we can’t burn the plants back without risking damage to the switch!”

“I’m afraid not,” Conrad muttered. “But it’s not far away, I’m sure of that.” He raised his own hatchet and began to chop at obscuring creepers. Within minutes he had laid bare a strange man-tall device of convoluted crystal on a white stone base. But that wasn’t what he wanted.

Someone else discovered an array of rusty metal wheels ia a circular frame which, on being touched, ground into movement for a few seconds and emitted a teeth-rasping hum. Again, a patch of creeper was cleared to reveal a human skeleton clutching an untarnished bar of metal with a knob at the end.

“Is that a tool of some sort?” Yanderman speculated, and drew Conrad’s attention.

It could be! Conrad called everyone together in the vicinity of the skeleton, and set to work with redoubled urgency.

When long minutes had passed without result, it occurred to Conrad that the man might have run, in the grip of madness, far from where he had been working. In sudden anger at his own stupidity he stepped back and hurled his hatchet to the floor.

There was a hollow boom.

Conrad stood for an instant like a statue. Then he was on hands and knees levering at the metal plates under him. His fingertips located a small depression in one of the plates, and Yanderman, peering closely at it, asked for the tool found in the skeleton’s grasp. It fitted the depression exactly, and when twisted caused the plate to rise on smooth counterweights … exposing a white board bearing a row of red switches.

Almost crying with relief, Conrad wiped his face; his skin was clammy with the sweat of tension.

“All right,” Yanderman said. “Which of these is the one?”

Conrad half-extended his arm, then drew it back. Paling, his eyes riveted on the switches, he whispered, “I–I don’t know. It could be any of them!”

Keefe made a strangled noise. The others exchanged glances of alarm.

“But we must find out!” Conrad exploded, and reached for the first switch. He had pushed it home before anyone could stop him.

There was a grinding sound. They looked up. Huge metal panels were swinging down towards them from the direction of the roof, ringing as they struck aside thick branches of creeper. A slow, tired-sounding voice spoke out of nowhere.

“Emergency transit operation due. Remain still.”

Convulsively Conrad forced the switch to its old position. The voice stopped. The metal panels hung like folded bats’ wings in the gloom above. The air seemed to congeal with tension.

“Try the one at the opposite end,” Yanderman muttered. Conrad complied.

At once there was another voice, equally tired. But this one said, “Emergency power reduction now in force. All travelways are now unpowered. All inessential services are withdrawn. No transits are possible until the system is fully restored.”

There was a grinding sound, and afterwards silence.

“Did you hear that?” Conrad whispered, getting to his feet. “Did it say what I thought it said?”

Yanderman nodded, his face set in a mask of awe. “It said something about emergency power reduction, and no transits being possible.”

“No transits!” Keefe echoed, almost shaking with excitement. “Does that mean no more monsters?”

“It must!” Conrad blurted.

And at that very instant the alarm which gave them warning of the arrival of such a monster blared deafeningly.

Somebody screamed. At once there was a panicky rush from the platform. Only Conrad, Yanderman and Keefe stood their ground: Keefe from sheer astonishment, Yanderman in much the same predicament but lifting his heatbeam as though determined to face any monster that might appear, and Conrad because he could not believe he had been wrong.

One or two of the fleeing men paused to hurl curses at him. Then they were gone, and there was a fearful hush.

“A-a fault in the system?” Yanderman suggested from a leather-dry throat.

“There can’t be a fault! Or a mistake!” Conrad passed his hand over his face dizzily, his mind churning with crazy images of Nestamay and Idris, Yanderman and Maxall, Lagwich and the sterile desert of the barrenland.

“Where do the things appear, do you know?” Keefe barked. “We do at least have a heatbeam! We might be able to trap it!”