The vision was blurred and Gary manipulated dials to bring it more sharply into focus.

"Wait a second," snapped Herb. His lingers reached out and grasped Gary's wrist.

"Turn it back a ways," he said. "I saw something out there. Something that looked like a ship. Maybe it's Evans coming back."

Slowly Gary twisted the dial back. A tiny spot of light danced indistinctly on the screen.

"That's it," breathed Herb. "Easy now. Just a little more."

The spot of light leaped into sharper focus. But it was merely a spot of light, nothing more, a tiny, shining thing in space. Some metallic body that was catching and reflecting the light of the Sun.

"Give it more power," said Herb.

Swiftly the spot of light grew, assumed definite shape. Gary stepped the magnification up until the thing filled the entire screen.

It was a ship — and yet it couldn't be a ship.

"It has no rocket tubes," said Herb in amazement. "Without tubes how could it get off the ground? You can't use geosectors in taking off. They twist space all to hell and gone. They'd turn a planet inside out."

Gary studied it. "It doesn't seem to be moving," he said. "Maybe some motion, but not enough to detect."

"A derelict," suggested Herb.

Gary shook his head. "Still doesn't explain the lack of tubes," he said.

The two men lifted their eyes from the screen and looked at one another.

"The Old Man said we were to hurry to Pluto," Herb reminded Gary.

Gary wheeled about and strode back to the controls. He lowered his gangling frame into the pilot's chair and disconnected the robot control. His lingers reached out, switched off the geosectors, pumped fuel into the rocket chambers.

"Find something to hang onto," be said, grimly. "We're stopping to see what this is all about."

CHAPTER Two

The mysterious space-shell was only a few miles distant. With Herb at the controls, the Space Pup cruised in an ever-tightening circle around the glinting thing that hung there just off Pluto's orbit.

It was a spaceship. Of that there could be no doubt despite the fact that it had no rocket tubes. It was hanging motionless. There was no throb of power within it, no apparent life, although dim light glowed through the vision ports in what probably were the living quarters just back of the control room.

Gary crouched in the airlock of the Space Pup, with the outer valve swung back. He made sure that his pistols were securely in their holsters and cautiously tested the spacesuit's miniature propulsion units.

He spoke into his helmet mike.

"All right, Herb," he said, "I'm going. Try to tighten up the circle a bit. Keep a close watch. That thing out there may be dynamite."

"Keep your nose clean," said Herb's voice in the phones. Gary straightened and pushed himself out from the lock.

He floated smoothly in space, in a gulf of nothing, a place without direction, without an up or down, an unsubstantial place with the fiery eyes of distant stars ringing him around.

His steel-gloved hand dropped to the propulsion mechanism that encircled his waist. Midget rocket tubes flared with tiny flashes of blue power and he was jerked forward, heading for the mystery ship. Veering too far to the right, he gave the right tube a little more fuel and straightened out.

Steadily, under the surging power of the spacesuit tubes, he forged ahead through space toward the ship. He saw the gleaming lights of the Space Pup slowly circle in front of him and then pass out of sight.

A quarter of a mile away, he shut off the tubes and glided slowly in to the drifting shell. He struck its pitted side with the soles of his magnetic boots and stood upright.

Cautiously he worked his way toward one of the ports from which came the faint gleam of light. Lying at full length, he peered through the foot-thick quartz. The light was feeble and he could see but little. There was no movement of life, no indication that the shell was tenanted. In the center of what at one time had been the living quarters, he saw a large rectangular shape, like a huge box. Aside from this, however, be could make out nothing.

Working his way back to the lock, he saw that it was tightly closed. He had expected that. He stamped against the plates with his heavy boots, hoping to attract attention. But if any living thing were inside, it either did not hear or disregarded the clangor that he made.

Slowly he moved away from the lock, heading for the control-room vision plate, hoping from there to get a better view into the shell's interior. As he moved, his eyes caught a curious irregularity just to the right of the lock, as if faint lines had been etched into the steel of the hull.

He dropped to one knee and saw that a single line of crude lettering had been etched into the metal. Brushing at it with his gloved hand, he tried to make it out. Laboriously, he struggled with it. It was simple, direct, to the point, a single declaration. When one writes with steel and acid, one is necessarily brief.

The line read:

Control room vision-plate unlocked.

Amazed, he read the line again, hardly believing what he read. But there it was. That single line, written with a single purpose. Simple directions for gaining entrance.

Crouched upon the steel plating, he felt a shiver run through his body. Someone had etched that line in hope that someone would come. But perhaps he was too late. The ship had an old look about it. The lines of it, the way the ports were set into the hull, all were marks of spaceship designing that had become obsolete centuries before.

He felt the cold chill of mystery and the utter bleakness of outer space closing in about him. He gazed up over the bulged outline of the shell and saw the steely glare of remote stars. Stars secure in the depth of many light-years, jeering at him, jeering at men who held dreams of stellar conquest.

He shook himself, trying to shake off the probing fingers of half-fear, glanced around to locate the Space Pup, saw it slowly moving off to his right.

Swiftly, but carefully, he made his way over the nose of the ship and up to the vision plate.

Squatting in front of the plate, he peered down into the control cabin. But it wasn't a control cabin. It was a laboratory. In the tiny room which at one time must have housed the instruments of navigation, there was now no trace of control panel or calculator or telescopic screen. Rather, there were work tables, piled with scientific apparatus, banks and rows of chemical containers. All the paraphernalia of the scientist's workshop.

The door into the living quarters, where he had seen the large oblong box was closed. All the apparatus and the bottles in the laboratory were carefully arranged, neatly put away, as if someone had tidied up before they walked off and left the place.

He puzzled for a moment. That lack of rocket tubes, the indications that the ship was centuries old, the scrawled acid-etched line by the lock, the laboratory in the control room… what did it all add up to? He shook his head. It didn't make much sense.

Bracing himself against the curving steel hide of the shell, he pushed at the vision-plate. But he could exert little effort. Lack of gravity, inability to brace himself securely, made the task a hard one. Rising to his feet, he stamped his heavy boots against the glass, but the plate refused to budge.

As a last desperate effort, he might use his guns, blast his way into the shell. But that would be long, tedious work… and there would be a certain danger. There should be, he told himself, an easier and a safer way.

Suddenly the way came to him, but he hesitated, for there lay danger, too. He could lie down on the plate, turn on the rocket tubes of his suit and use his body as a battering ram, as a lever, to force the stubborn hinges.