r Delegate, Mr. James."

"Who told you to send men to bomb the _Polaris_?"

"My superior," said the man.

"Your superior--your superior!" Walters' voice was edged with contempt.
"What else has your superior told you to do?"

"A great many things," said the young man simply.

Walters studied the thin face and then turned to Captain Strong.
"There's only one thing to do, Steve. There's no telling how many of
these rats are inside our organization. Relieve every civilian in any
position of trust and put in our own man. I'll make a public teleceiver
broadcast in half an hour. I'm declaring martial law."

"Yes, sir," replied Strong grimly.

"If you hadn't been in the code room when this message from Mercury came
in, we would never have known the Nationalists were trying to get the
Mercurians to join them in their attack on us until it was too late.
It's the only break we've had, so far, learning that the Mercurians are
still decent, loyal Solar citizens. I hate to think of what would have
happened if they hadn't warned us."

"He very nearly got away with it, sir," said Strong. "If I hadn't heard
the signal for a top-secret message come through on the coding machine,
I never would have suspected him. He tried to hide it in his tunic. He
also confessed to trying to kidnap the cadets when he heard me tell them
that a cab would be waiting for them."

"Well, we know now," said Walters. He turned to one of the guardsmen.
"Sergeant, I'm holding you personally responsible for this man."

"Aye, aye, sir," said the guard, stepping toward the secretary, but
Walters stopped him and addressed the man.

"I'll give you one last chance to tell me where your base is and how
many ships you have," he said.

The secretary looked down at his feet and mumbled, "I don't know where
the base is, and I don't know how many ships there are."

"Then what does this list we found in your tunic mean?" snapped Strong.
"These are the names of ships that have been lost in space."

"I don't know. That list was sent to me over the audioceiver by my
superior. I was to relay it to Mercury should they accept our proposal
to join forces against--" He stopped.

"Get him out of my sight!" barked Walters.

The guards closed in around the little man and he slowly shuffled out of
the office.

"I wonder how many more there are like him in our organization, Steve?"
The commander had turned to the window and was staring out blindly.

"I don't know, si