"They lined up and watched the body floating alongside," Kass added somberly. "And that Mug was as human as you or I."

Their words recalled the scene vividly to Sine's mind. The broad, green field between two crescent lakes. The beetling-browed wretch, with eyes full of fear that darted from side to side, led to the center of the field by two splendidly armed warriors, there to be left alone in an agony of uncertainty.

He saw again the half-hundred clean-limbed athletes, sons of rich Jovian families. They were lined upon each side of the field. At the signal they dashed in. The frightened labor Mug tried to escape. As one team closed in he doubled, ran directly toward the others, saw his mistake too late. There was a brief savage scrimmage, and the unfortunate victim was stretched unconscious on the sward, while the victors and the vanquished in this curious game joined arms and made for the baths where exquisite nymphs peered coquettishly from behind delicately proportioned columns. Sine reaped uncomprehending and resentful stares when he declined to join them.

"Too rich for my blood," Sine told his companions at breakfast as they discussed their experiences. "Hope they take us to Rubio soon. We've done our job, and as for me, I'm not cut out for high Society."

After they had completed their breakfast a girl came hesitatingly into their chamber. Sine stared at her curiously. She had none of the enameled beauty of the women he had seen until then, but in her young face was a subdued comeliness that was attractive after the assertive pulchritude that was universal among the young women of the First Race. Unlike the shrewd display of their chiseled perfection, this girl's slender, rounded body was wrapped in a thin, gray garment that concealed as it draped. It was caught by a cord around her waist. Her feet, smaller and more fragile than the sturdy Jovian standard, were encased in neutral buskins. She stood submissively, waiting for them to speak.

"What does that girl want?" Kass murmured aside. "My stars, she can't be a labor Mug!"

"Come here, girl!" Lents rumbled kindly. "What can we do for you?"

The girl came forward hesitatingly. Her voice was soft, lacking the brassy assurance of other Jovian women;

"I was sent here, masters, to guide you through hell."

Immediately after this startling statement her face turned a brilliant red, then a deathly white. She half turned as if to flee, but, as if realizing the uselessness of flight, she faced them again, defiantly;

"I don't care what happens to me!" she declared desperately. "I've told the truth at least once. Jovians call this place The Pleasure Bubble, but they don't have to live in the black half. Now tell them what I have said."

"We will not tell anyone what you said, child," Lents rumbled comfortingly. "But tell us. You don't look like the Mugs we've seen so far—nor like the poor fellow we saw put through the airlock. They seemed—a different race. But you—why—on Earth we could hardly tell you from any other kid of your age."

A flash of spirit illuminated the girl's tragic, immature face.

"They call us a different race!" she exclaimed. "True—but not an inferior race! They are the inferior race, though the stronger. They depend on our knowledge, our labor, to live! My father told me so!"

Kass, who had been studying her silently, asked, "Your father?"

"Yes. The technic in charge of the machinery below. He was ordered to escort you around. But his scars from the rays make it hard for him to breathe today. He is in his bunk. So he sent me in his place."

Sine wondered if life under such unnatural and destructive conditions would some day reduce this graceful girl to a horrible parody of humanity. He asked;

"Do you work below?"

Her clear gray eyes fell on him.

"No. I was selected by the Committee to work in the Baths when I am sixteen. I am fifteen now."

"Holy twisted nebulae!" Sine swore under his breath. "The kid doesn't know what her work in the Baths is going to be! So the Committee selected her for the Baths!" He felt suddenly a violent dislike for the very rich Jovians, a feeling of fraternity with the Mugs.

"We will be very glad to have you guide us," he said formally. "What is your name?"

"Proserpina. My father said it is fitting for one who lives where we do."

Strange anachronism! That name from the mythology of Earth's youth. Like that goddess of the underworld from misty antiquity, she led them down, down, until it seemed they must be near the bottom of the black hemisphere. It was a world of dim distances, of shadows, of pipes and girders, or grisly abysses from which came mysterious sounds; of locked chambers in which ghastly fires flared.

Now and then they met the inhabitants of the place; misshapen Robolds going about unknown tasks. They stumbled suddenly out of unnoticed passages, carrying burdens, grotesque, apelike, weary. Most of them were hideously deformed.

Several times, when their journey led them into a certain part of the hemisphere where they felt strange tingling of their nerves, the girl led them away.

"We must not go there," she told them. "The integrators are there. There my father received the scars of his chest that keep him from breathing. Most of those who are blind worked there."

The Earthmen had already heard hints of the atomic integrators from which the Jovians obtained endless power. They had no desire to get too near those searing by-products of power.

"Do you mean to say," Lents asked, puffing a little from their exertions, "that people down here live here all their lives?"

"I will show you our home," Proserpina said simply.

They came to it presently. A niche, a metal-laced nook, deep in the hull. Gigantic girders formed one side of it. On the other side enormous air conduits. It was clean, bare, not as depressing as they had expected. It was more like a gallery, long and narrow, sparsely furnished.

Something rolled out of a bunk at the farther end. Something like a great spider. A man, stooped over, his once powerful body doubled, so that his knuckles almost dragged on the floor-plates. He came toward them, fierce gray eyes looking out at them under bushy brows. So formidable that Sine's muscles tensed.

"Are these the visitors, Proserpina?" His voice was husky, as though his constricted chest with difficulty performed its function. He looked at them intensely.

"They tell me you are from Earth. Are you with us or against us?"

"Father, be careful!" She put her hand over his mouth, to be shaken off impatiently. But the girl's warning had taken effect. The man—it was impossible to tell if he were old or young—looked at them broodingly.

"My mother died here," Proserpina said. "And I am afraid he will. His mind is not as clear—"

Lents, distressed to the bottom of his generous soul, helped the victim of the Jovian pleasure moon back to his bunk. "This girl," he muttered to Kass, "can't we get her out of here?"

He had not meant for her to hear, but her quick ears caught his words, and a ray of hope illuminated her features. She was standing beside Sine, and her thin fingers gripped his hard bronzed arm;

"Oh, could you take me away? I will be your slave!"

Sine gently disengaged her fingers. He was strangely embarrassed.

"I'd like to. But I'm a bachelor man. No place for you, you know."

She did not persist. No doubt she realized that she could not leave that gaunt parody of a man who was her father.

When they bid farewell to Proserpina they were steeped in profound depression. Alone in their room, they talked over what they had seen, but they could think of no way to save Proserpina from her fate. They were still discussing their visit when the manager of this satellite of delights called on them and informed them that Governor Nikkia of Jupiter awaited them in the capital city, Rubio. A space ferry was even then clamped to the locks to