Long they sat thus, Ylia enjoying her task and Bram Forest's facile mind drawing in each syllable she spoke and committing it to memory.
Finally the sun lowered and the interior of the cavern darkened until they could no longer see each other. The most important conviction Bram Forest arrived at from Ylia's discourse was indeed a startling one. He was certain that this Tarth was a twin planet to Earth of which there was complete knowledge in his mind. He could hardly escape the fact that Tarth swung in an orbit exactly opposite to that of its more familiar counterpart, thus remaining invisible from it.
This conviction came to him through several things Ylia said and it was buttressed by a bit of Tarthan mythology she chanced to mention. The legend told of a flame-god, obviously the sun, which stood forth in its wrath one long-distant day and hurled two great stones at a demon who came from far away bent upon torment. This last Bram Forest thought, was perhaps a comet of great size that tore both worlds from the sun and set them upon their orbits. The existence of the mythological legend indicated too, that civilization on Tarth was not backward or at least had not been in ages gone.
In the more exact realm, Bram Forest learned that Tarth was far less watery than its invisible sister, scarcely half its surface consisting of ocean. It had two ice caps at the poles, known as the Outer Reaches and an equator termed the Inner Belt.
There were no isolated continents according to Ylia's map, all the dry surfaces being connected by wide passages of land through the continuous ocean.
Ylia's description of the people interested Bram Forest most intensely. On Tarth, he learned, there was no association of nations, each mistrusting the others in a world where a state of continuous war at some point of the globe was an accepted state of affairs which no one sought to ameliorate.
Ylia herself was hazy upon the description and number of the nations. She thought some two hundred existed but only the most important could she describe.
The Abarians were the most successfully warlike, fearing only the Nadians to the south. This because though the Nadians were not aggressive and even treated other lesser nations in a kindly fashion, they possessed an inherent fighting skill and a power potential that had not been tested in recallable history. Though they had not fought for centuries, their potential had not lessened because such a folly would have been considered tantamount to national suicide on Tarth.