een able to set such a trap? Had they known all
the time of the presence of the humans on the mountain above them? They
had known something. Otherwise they would not have been able to set the
trap. How had they learned of the attack? How had they known the exact
way the attack would come?

"Yah!" a voice shrilled from outside. "How do you like it now, you big
fat-head?"

Voronoff's voice! Voronoff was out there! Craig's first dazed thought
was that Voronoff's presence outside, among the Ogrum, was impossible.
He tried to remember when he had last seen the man. He hadn't seen
Voronoff all day! Voronoff had not been a member of his group but he had
assumed the man had attached himself to some other group!

Voronoff had not attached himself to some other group. Voronoff had come
secretly to the Ogrum. It was Voronoff who, as far as he knew them, had
revealed the plans of the attack to the Ogrum. Voronoff was a traitor!

"You wouldn't believe me when I said you were just getting us all
killed!" Voronoff exulted. "I wasn't going to get myself killed with you
fools. I told the Ogrum what you were planning. They're going to make me
a chief."

In a flash Craig saw why phase one and phase two of the attack had gone
off so smoothly. The Ogrum had permitted the smashing of the hangar.
What were a few planes? They could build more. What were a few grass
huts? They could erect a thousand others. The destruction of the planes
and the burning of part of their city was a small price to pay if they
could trap all the remaining men of the Idaho.

Craig cursed himself. He had not thought of the possibility of anyone
turning traitor. He should have thought of it. Back there in the
life-boat, while he was asleep, someone had stolen water. Voronoff was
the only person who would have stooped to steal water when water meant
life, and the only person clever enough to accuse Craig of the crime he,
himself, had committed.

"I should have choked that dog to death!" Craig said bitterly. "I should
have thrown him to the sharks."

Captain Higgins had come forward and sized up the situation. "No use
crying over spilt milk," he said to Craig. "I don't blame you for not
thinking of a traitor and I think no one else will blame you. The
question is, what are we going to do?"

"What do you want?" Craig shouted.

"The Ogrum demand unconditional surrender!" the answer came. "They say,
if you will surrender, that half of you will have to be offere