to master his faculties of concentration
and thought.

Bradley repeated his questions sharply.

"I am An-Tak, the Galu," replied the man. "Luata alone knows how long
I have been here--maybe ten moons, maybe ten moons three times"--it was
the Caspakian equivalent of thirty. "I was young and strong when they
brought me here. Now I am old and very weak. I am cos-ata-lu--that is
why they have not killed me. If I tell them the secret of becoming
cos-ata-lu they will take me out; but how can I tell them that which
Luata alone knows?

"What is cos-ata-lu?" demanded Bradley.

"Food! Food! There is a way out!" mumbled the Galu.

Bradley strode across the floor, seized the man by his shoulders and
shook him.

"Tell me," he cried, "what is cos-ata-lu?"

"Food!" whimpered An-Tak.

Bradley bethought himself. His haversack had not been taken from him.
In it besides his razor and knife were odds and ends of equipment and a
small quantity of dried meat. He tossed a small strip of the latter to
the starving Galu. An-Tak seized upon it and devoured it ravenously.
It instilled new life in the man.

"What is cos-ata-lu?" insisted Bradley again.

An-Tak tried to explain. His narrative was often broken by lapses of
concentration during which he reverted to his plaintive mumbling for
food and recurrence to the statement that there was a way out; but by
firmness and patience the Englishman drew out piece-meal a more or less
lucid exposition of the remarkable scheme of evolution that rules in
Caspak. In it he found explanations of the hitherto inexplicable. He
discovered why he had seen no babes or children among the Caspakian
tribes with which he had come in contact; why each more northerly tribe
evinced a higher state of development than those south of them; why
each tribe included individuals ranging in physical and mental
characteristics from the highest of the next lower race to the lowest
of the next higher, and why the women of each tribe immersed themselves
morning for an hour or more in the warm pools near which the
habitations of their people always were located; and, too, he
discovered why those pools were almost immune from the attacks of
carnivorous animals and reptiles.

He learned that all but those who were cos-ata-lu came up cor-sva-jo,
or from the beginning. The egg from which they first developed into
tadpole form was deposited, with millions of others, in one of the warm
pools and with it a poiso