"Because Earth is nearer the Sun, humans have a possibility that we do not have. What we tried to show these humans was a method whereby they could change the embryonic physiology so that the adult human would be able to use the energy of solar radiations directly, instead of depending on the energy of combustion of those chemicals you call oxygen and carbon. This makes the body independent of both air and food, and has the advantage also of giving a far superior regenerative power to the bodily tissues.
"The human, Goat, for reasons that are not known, stole some of our charts and two of the pregnant female humans, and continued his work at this place to which we are going. But he thought he was still attempting to change the physiology so that oxygen could be stored, and therefore his experiments went wrongly."
"But he had your charts," objected Maya. "Even though he was not making the alterations he thought he was, how could he go wrong if he followed the charts?"
"The charts showed the changes to be made in the embryonic cells, but they could not show the method whereby the changes are made," replied Qril. "The human, Goat, attempted to make these changes by mechanical, surgical methods but these are too crude to be successful. The method we utilize to make such changes, which is the only right method, is to focus the mental forces upon the embryo. I believe you would call it psychokinesis."
Maya was vastly excited at this revelation.
"Then Goat's oldest experiments, the ones he called Brute and Adam, were actually the ones on whom you children of the past had performed the embryonic changes!" she exclaimed. "They must have been the sons of the pregnant women he kidnapped. That's why they were more successful than the others!"
"That is true," said Qril. "We had completed the change on only one of the two, therefore only that one would develop into an adult who could live in complete independence of air and food, if necessary. The other one would never be able to do it for more than a short period without returning to terrestrial conditions."
The party now came over a long low ridge, and the mass of Ultra Vires rose from the desert ahead of them. The sun was near setting, and the black walls of the stronghold huddled sullenly under its crimson rays.
The Martians left them here, and Nuwell and Maya went on alone toward their goal. Nuwell expelled an audible sigh of relief.
"I'm glad we're free of those monsters," he said. "I don't understand how you could carry on a conversation with such creatures, Maya. It sounded like a series of animal grunts and cries to me. I caught an occasional word, like 'oxygen' and 'psychokinesis.' What were you talking about?"