There were, Bo explained, two sides to the earth: the inside and the outside. It was a hollow ball, with a crust 500 miles thick, and people walked around the inside just as they did the out. Their light was a small sun suspended at the dead center, a ball of molten flaming gas at the earth's core, and most of this inner world enjoyed a perpetual noontime save for a land of shadows, which was cast into eternal eclipse by an interior moon.
"There's as much land there as here," Bo continued, "And most of it is as wild and untamed as the Earth at the dawn of time. It's still the stone age there, though of late a few of your outer earthlings have brought back weapons and science enough to colonize a good portion of it and set up a sort of fledgling empire. But never mind them, the Kosars are a seafaring people, and always have been."
He went on to explain that the Kosars explored the Kosar Az, the greatest ocean in this Inner World which he called Pellucidar.
"We Kosars long ago discovered the secret of the two-sided world, as there's a portal at the North Pole and we went through it back and forth freely for centuries," he explained. "We mixed with you timid Northern outerlings, we did, and we learned some of your ways, which put us ahead of the rest of Pellucidar. We also mixed with your women, and I doubt there's a soul among you in these Northern provinces who's without Kosar blood."
"What?" Zartan finally found the strength to raise his voice, but could barely make one word. He was too dismayed and too drunk to say anything else.
"How else would ye ever have the tempermant to man Viking ships and ransack the coasts of Europe?" Bo asked hypothetically. "How else do ye explain these tales, where yer Grendels and Dragons sound exactly like the inlandish monsters of Pellucidar, the sithics and thipdars?"
He looked to Zartan for some response, but Zartan was too perplexed by the tale to argue or ask questions. He felt that Bo had probably drank himself into raving lunacy.
"Ay, well, there's no sense in me trying to persuade ye," Bo said at last. "Ye'll be seeing it all for yerself soon enough, ye will, for that's where we're both going. We're manning a pirate fleet in Pellucidar, with the sole purpose of taking it back from these usurpers!" He took the glass, and, remembering now that it was drained, hurled it instead against the far wall. The glass shattered into a thousand pieces.
Bob, who had been sleeping contendedly with a bellyfull of seed and other treats, now awoke and squawked. "No good, no good, no good!" he shouted shrilly.
"It's just something he says," Zartan told Bo. "Never mind that fool bird." He shook a fist at Bob, but privately thought, "what have I got myself into?" For he knew that Bob was blessed with the ability to see slightly into the future, and though he was not always right, he seemed to speak of Bo and this new journey with an extraordinary conviction.