A great multitude of lesser members surged toward the exit, while those chosen to remain grouped forward under the flaming diamond star, whose light veiled the ten members of the _Dekka_. For the ten leaders of their order of whom Astran was the foremost, might be known by their names, recognized by their voices, but they were never seen. There was a saying that all others "could enter the light, but could never touch the flame." All the waning night, while Io revelled in a fantastic carnival of pleasure, they gave their reports in minute detail, and the ten minds on the dais that formed the Dekka, made calculations with infinite patience and fed them to the Neuro-graphs by their desks complicated cerebro-geometric figurates were set up, and woven into the matrix of their problem. The possible influence of certain key figures in the Societies of other Moons whose intelligence, emotional stability and intellectual attributes were known, was reduced to high-level variables, and again fed to the marvelous machines together with the relevant data culled from the members present. Astran was like a raging juggernaut, asking questions, prodding laggard memories, directing the other nine members of the Dekka. He was tireless, and pitiless. How at his great age he could accomplish it, was a mystery. But it had been that boundless energy and stupendous will that had been responsible for the greatness of Io--not to speak of the _Dekka_. _He must be over two hundred!_ Julian thought with awe, recalling dimly the "Memoirs" of an earlier historian whom Astran had commissioned to compile a history of Io, and in so doing had managed to bedevil that poor man's life to such an extent, that the historian had counted the cessation of Astran's visits as among the compensations for dying!... That had been fifty years ago, when already for a century Astran had led the Dekka. At last, the Neuro-Graph machines, marvelous as they were could do no more. Out of that welter of figures, endless reports and calculations, one master mathematical conclusion remained. _The answer lay in Ganymede!_ It suddenly occurred to Julian just how ghastly was the irony of their position. For their ancestors in gaining all the "conditions of freedom," had gained far more than they'd bargained for, including this epidemic of Mutations that in rendering them sterile sealed the doom of their Moons. Had _Terra_ known it, this was the perfect answer--a few decades and all of them would remain only as a Mars-dry chapter in history. They had sown the whirlwind ... and were reaping extinction! And Julian found a kindred feeling in the vast capacity for sheer destruction that Astran had hinted at tonight. If the answer lay in Ganymede with its dual civilization of Terran mutants and their descendants, and the original Ganymedean race, he meant to visit that stupefying world of cabals and intrigues and unrivaled luxury. * * * * *