hat the human called Goat had developed were not
what he thought," replied Qril. "We tried to help the humans to find the
right course, but they could not understand us well. We tried to show
them, by charts and example, that the proper way to adapt a human to
Martian conditions was a different way.

"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 Ultr