Sufficient supplies of food had been already stored, the machinery for lighting the caverns was complete, and solid oxygen had been enclosed in steel reservoirs to supply what would be consumed by respiration, while provision had also been made for continually abstracting the carbonic acid and other injurious constituents from the respired air. Everything that human genius and skill at their best could do to ensure the preservation of this remnant of humanity, had been done, and by the 15th of September the caverns were finally ready for occupation. Only one more task now remained to be completed, and this was the selection of those who were to survive, provided that the precautions taken proved adequate. Unspeakably pathetic as this work of selection was, it was performed with a calm and apparently passionless precision worthy of the unparalleled solemnity of the occasion and the splendid traditions of those who accomplished it. The field of selection was first narrowed by confining it to those who had been regularly betrothed when the first message was received from Mars. From these first the physically perfect were chosen, then the strongest and the fairest of these, and finally those who to their physical perfections added the highest intellectual and moral qualities. The work was performed by the Ruling Council assisted by a council of an equal number of matrons who had what had once been accounted the misfortune to be childless. Neither joy nor sorrow was shown, at least in public, either by those who were chosen or by those upon whom the joint Council was forced to pronounce sentence of death by rejecting them. The natural joy of the chosen was lost in the universal sorrow of the now inevitable parting, and those who were destined not to survive, satisfied with the perfect justice with which the selection had been made, consoled each other with the knowledge that they would die hand in hand and be spared the sorrow of surviving all who were nearest and dearest to them. On the morning of the 18th, the temple of Aeria witnessed the last ceremony that would ever take place within its walls. This was the marriage of those who, unless their last refuge shared in the destruction that was about to bring chaos upon earth, were to be the parents of the new race that was to repeople the world. The survivors of the whole nation now barely filled the vast interior of the temple. The solemn words which bound youth and maid together as man and wife to face side by side the last ordeal that humanity would ever have to pass through were spoken in the midst of a silence which reigned not only in the temple but now throughout the whole valley.