and unearthly danger of the interplanetary frontier.

He hardened himself against the qualms of conscience. There was that at stake, he told himself fiercely, against which the safety of a lot of spoiled, rich young people was absolutely nothing.

Holk Or was chuckling as they emerged into the chill Martian night. He told Kenniston admiringly, "That was one of the smoothest jobs of lying I ever heard, that story about finding John Dark's treasure. Take it from me, it was slick!"

The Jovian guffawed loudly as he added, "What would their faces be like if they knew that John Dark and his crew are still living? That it was John Dark himself who sent us here?"

"Be quiet, you idiot!" ordered Kenniston hastily. "Do you want the whole Patrol to hear you?"

CHAPTER II

Discovered

he Sunsprite throbbed steadily through the vast, dangerous wilderness of the asteroidal zone. To the eye, the cruiser moved in a black void starred by creeping crumbs of light. In reality those bright, crawling specks were booming asteroids or whirling meteor-swarms rushing in complicated, unchartable orbits and constantly threatening destruction.

For three days now, the cruiser had cautiously groped deeper into this most perilous region of the System. Now a bright, tiny disk of white light was shining far ahead like a beckoning beacon. It was the asteroid Vesta—their goal.

Kenniston, leaning against the glassite deck-wall, somberly eyed the distant asteroid.

"We'll reach it by tomorrow," he thought. "Then what? I suppose John Dark will hold these rich youngsters for ransom."

Kenniston knew that the pirate leader would instantly see the chance of extorting vast sums by holding this group of wealthy young people as captives.

"I wish to God I hadn't had to bring them into this," Kenniston sweated. "But what else could I do? It was the only way I could get back to Vesta with the materials."

His mind was going back over the disastrous events since the day three weeks before, when the Patrol had caught up to John Dark at last.

Dark's pirate ship, the Falcon, had been gunned to a helpless wreck. It had, fortunately for the pirates, drifted off into a region of perilous meteor-swarms where the Patrol cruisers dared not follow. The Patrol thought everybody on the pirate ship dead anyway, Kenniston knew.

But John Dark and most of his crew were still alive in the drifting wreck. They had fought the battle wearing space-suits, and that had saved them. They had clung grimly to the wreck as it drifted on and on until it finally fell into the feeble gravitational pull of Vesta.

Kenniston could still remember those tense hours when the wreck had fallen through the satellite swarm of meteors onto the World with a Thousand Moons. They had managed to cushion their crash. John Dark, always the most resourceful of men, had managed to jury-rig makeshift rocket-tubes that had softened the impact of their fall.

But the wrecked Falcon had been marooned there in the weird asteroidal jungle, with the alien, menacing Vestans already gathering around it. The ship would never fly space again until major repairs were made. And they could not be made until quantities of material and equipment were brought. Someone must go for those materials to Mars, the nearest planet.

John Dark had superintended construction of a little two-man rocket from parts of the ship. Kenniston and Holk Or were to go in it.

"You must be back with that list of equipment and materials within two weeks, Kenniston," Dark had emphasized. "If we stay castaway here longer than that, either the Vestans will get us or the Patrol discover us."

The pirate leader had added, "The moon-jewels I've given you will more than pay for a small cruiser,