int accent. Somehow, I have a hunch they're Brungarians."

Ames whistled. "That could spell trouble, skipper." More than once,
Brungarian rebel agents had engaged in brazen plots against America and
the Swifts.

"Let's hope I'm wrong," Tom said wryly.

"Art Wiltessa--and the Navy--called again," Ames added. "Still no luck
on the missile search."

The gloomy news did nothing to lift Tom's spirits. The next day, hoping
to verify or disprove his suspicion, he drove to Shopton Police
Headquarters with Harlan Ames. The two talked briefly with Chief Slater,
an old friend. Then a turnkey took them to the cell block.

The four prisoners had been confined in a single large cell. They seemed
tense and angry--as if they had been quarreling among themselves.

"Ready to talk yet?" Ames asked. Getting no reply, he repeated the
question in Brungarian.

Ames's ruse failed. "What language is that?" asked "Captain Smith"
mockingly. "Pig Latin?"

As his cellmates grinned, Tom's eyes roved over their faces. One
man--wavy-haired with penetrating dark eyes--seemed oddly familiar. Why?
Suddenly the answer hit Tom like a flash. He resembled Streffan Mirov,
the brilliant Brungarian rocket scientist who had tried to oust Tom's
expedition from the phantom satellite Nestria.

Playing a hunch, Tom said to him, "You know what your government does to
rebels and bunglers, Mirov."

The man stiffened and paled. "We have not b-b-bungled!" he stuttered
angrily.

"Shut up, you fool!" their leader shouted.

CHAPTER VI

THE CAISSON CLUE

"Captain Smith" had leaped to his feet, quivering with anger. But it was
too late. His cellmate, by answering to the name of "Mirov," had given
away their nationality!

Tom and Ames exchanged grins of triumph.

"No doubt you recall what happened to Streffan Mirov," Tom went on,
pressing his advantage. "Or should I say the _late_ Streffan Mirov? Our
last report was that he had been tried and condemned by your own
government. Perhaps you can give us news of his fate?"

The wavy-haired prisoner's eyes blazed with hate. "Grin while you can,
Tom Swift! Because of you, my brother Streffan is now serving a long
prison sentence! But I, Dimitri Mirov, will get revenge!"

"You blame Tom Swift because your brother botched his job of claiming
the satellite Nestria by force and fraud?" Ames taunted.

"Our space friends moved that asteroid into orbit around the earth," Tom
added. "We claimed it by right of