re floating fortresses. The war
is done but we have left guards in the sky to protect us if we are
attacked. The sphere that attacked you was one of our automatic forts
which we had left in the sky."

"Ah!" said Hargraves. The cold logic of his mind sought a pattern that
would include fortresses in the sky. Presuming war between two planets,
such fortresses were logical. But--

"The construction of such a sphere indicates vast technical knowledge,
tremendous workshops. I have seen no laboratories and no industrial
centers that could produce such a fortress. I have, moreover, seen no
civilization that will serve as a background for such construction."

* * * * *

He waited for an answer. Usher, the archeologist, looked suddenly at
him, then looked at Thulon.

"The fortresses were built long ago," Thulon said. "In those past
milleniums we had industrial centers. We no longer need them and we no
longer have them."

"Then there _is_ another stage!" the archeologist gasped. "You are past
the city stage in your evolutionary process. You are beyond the metal
age. What--" Usher eagerly asked. "What comes after that?"

"We are beyond the age of cities," Thulon answered. "The next but
possibly not final stage is a return to nature. We live in the groves
and the fields, beside the lakes, under the trees. We need no protection
from the elements because we are in unison with them. There are no
enemies on this world, no dangers, almost no death. In your thinking you
can only describe us as gods. Our activities are almost entirely mental.
Our only concession of materialism is this." He lifted the staff. "When
you fired at me, this staff canceled your beams. It would have canceled
them if they had been a thousand times stronger. When one of you
attempted to destroy Sarkoff, force went out from this staff, knocking
the weapon from his hand. There are certain powers leashed within this
staff, certain arrangements of crystals that are very nearly ultimate
matter. Through this staff my will is worked. Some day," he smiled, "we
will even be able to discard the staff. That is the goal of our
evolution."

The thoughts went into soft silence and Thulon looked down at them.
"Does that satisfy you?" His eyes went among the group, came to rest on
Hargraves. "No, I see it does not. There is still one fact that you
cannot fit into your pattern."

"Yes," said Hargraves. "If all that you have told us is true,