The men of the _Kastil_ had dodged away into the darkness.

Scott's voice rang out harshly. "I'll give you men two minutes to organize and get out of here. If you're not out by that time, we'll spin our jet around and burn you out."

There was a brief stir off in the shadows.

"You're in a blind alley there," Scott continued. "There's no way out.

And we'll blast any man who tries to climb out over the rocks. Is that clear?"

A glowing flash of energy exploded against the rock protecting him.

There was no sound, but bits of stone lightly flecked his suit. Scott braced himself on the rough face of the boulder and worked the blaster around for an open shot.

"No more shooting," the heavy voice of the tall man growled. "You _Bertha_ people. Can you hear me?"

"Yes," Scott said coldly. His eyes probed the shadows for motion.

"We're willing to be peaceful about this. I'm Captain Randell of the _Kastil_. There's no need for killing when there's plenty of ore for all of us."

"Not in this pit," Scott answered. "You have one minute."

"All right." Randell's voice, distorted as it was by the tiny radio, carried a sardonic edge. "We'll go--from here."

He sauntered out of the shadows, hands upraised. From the tangle of stone, his men crept out to join him. Without haste, insolent in their retreat, they crossed over the pit.

At the far side they paused. "This is the extent of your so-called claim." Randell's voice purred in their ears. "Our claim extends from this line. And if a man from the _Bertha_ wants a quick blasting, he can cross this line." His radio snapped off with crisp finality.

Scott stepped from his shelter.

"All right," he ordered. "You men know the story. The _Kastil's_ down here ready for work. And it's going to mean work if we're going to beat her back to Earth. Now, let's go. But watch your step."

They worked. Eighteen hours a day they worked. From the steel-like ground they scooped a dozen tons of the dirty black uranium ore and sent it hurtling back to the _Bertha_.

But in spite of all their efforts, the more modern equipment of the _Kastil_ overtook them in a day. The blackness on their left was riddled with the flare of digging torches and the slender fire-trails of the jets soaring between the pit and the _Kastil_.

And now and again, Randell's drawling voice broke into Scott's ears.

"You're slowing up, _Bertha_. Seventy tons for us today. Are you poor little men getting tired?" He clucked sympathetically, then burst into a yell of laughter. "We'll have the ore cleaned off this rock before you get half loaded."

But Scott and the men of the _Bertha_ worked silently, with savage haste, forgetting sleep and food to keep the tonnage flowing to their ship. They had almost forgotten the cats....

But not for long.

Staggering with fatigue, Scott swayed into Central Control, and sagged into a seat. He had been too long in a s.p.a.ce suit. A dull pounding beat behind his eyes. "I came as soon as you called the pit, Captain Elderburg. You sounded pretty urgent."

"It's urgent," Elderburg said. "We're beaten."

Scott stiffened. Fatigue fell from him as he gazed closely at the Captain, saw for the first time the bitter dullness of Elderburg's eyes.

"You better come with me," the Old Man said heavily. He rose stiffly, led the way from the room.

In silence they shuffled down the corridor toward the engine room. A tic worked at the corner of the Captain's mouth, but he did not seem to notice it. "Durval held the cats off with ultra-sonics. He purified about ten tons of the stuff and stored it."

They threaded their way along a chill black catwalk to the center of the ship. In the engine room, men slumped sullenly among the big atomics. As Scott and Elderburg pa.s.sed a group of the black gang, mutely dangling wrenches, there was a sudden stir.

"That's him!" One of the men had leaped up. The wrench whipped back over his shoulder. He leaped raging toward Scott. "There's the rotten...."

"Easy, Billy." He was dragged back, disarmed.

"How'd the _Kastil_ know...."

The Captain tugged Scott's arm. "Don't bother with them. Come on."

Scott nodded numbly, followed, his head aching and a nameless wave of apprehension sliding through him. "Where are the cats?" he asked once.

Elderburg ignored him. "Put on a radiation suit."

They had stopped before a side door of the main hold. As Scott struggled into the suit his mind swirled in a chaos of thoughts. When the suit was adjusted he dropped the helmet shut and stepped forward. Through the lighter gravity of the air lock they lumbered. Then Elderburg spun the controls that opened the door.

"There you are," he said to Scott. He sounded completely deflated. No sting remained in his voice.

Scott stepped forward into the hold, then froze. His body went cold.

The hold was a writhing ma.s.s of cats.

Their queer angled bodies darted in a great pile beyond the door. Their red bodies glowed and twisted strangely. They flew about a huge stack of lead containers--uranium cells secured for the long trip home.

And Scott went sick with understanding. Through rigid lips, he forced the words: "Energy-eaters!"

The Captain laughed oddly. "And you wondered how they lived on this naked rock. They ate the raw ore, of course. No wonder they hung around Durval's machines sucking up what free energy they could. They broke through the air feeder system here. No wonder. With cells of 80% pure uranium waiting for them." His voice broke.

"So we're finished," he continued. "The _Kastil_ will be loaded before we can even clean the cats out. We're done."

He swayed back against the bulkhead. Scott took his arm.

"Get away from me." Elderburg wrenched away, his loathing clear even behind the bulky suit. "If what the men say is true. If you sold us out--" His voice trailed off. "Call your men out of the pits, Jerill.

We're blasting off tonight."

"No." Scott leaned forward, his eyes mere slits behind the lense of his helmet. "Is there any uranium left?"

"We saved two cells."

"It's enough," Scott snapped. His lean jaw lifted proudly. "It's a little late, Captain. But I can promise to get rid of the cats in two hours. With the ore deposits Vaugn and I have collected, we can still load a good cargo and beat the _Kastil_ out by at least a day."

Elderburg eyed him sharply. "How can you handle the cats?"

"Get me a lead-lined box about eight feet by...."

Static blasted shrilly in their ears. The voice of the ship's lookout, strained with excitement, shouted. "Captain Elderburg. This is Main Control. Get here fast. An explosion at Lieutenant Jerill's mine."