"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.