"If only we could find the way to break or soften that outer rind," said Jeter.
"What can we do?" asked Eyer. "If it is impervious to the cold of these heights; if it is so strong that it is impervious to the tremendous pressure inside the globe—which must be kept at a certain degree to maintain human life—what can we do? We tried bullets. We might as well have used peas and pea-shooters. If our friends try bombs they will still be unsuccessful. If only we could somehow open up the outer rind or soften it, so that our friends could see the inner globe and reach it with their bombs!"
Jeter's face was now dead white. His eyes were aglow with excitement.
"Tema," he whispered, "Tema, that's their vulnerability! That's what they fear! They're scared that the outer rind may be broken—which would spell destruction to the space ship and everybody in it."
"Including us," replied Eyer, "but, anyway—well, what's the odds? We're only two—and with this thing destroyed the nightmare will end. Of course there should be some way to raid the Lake Baikal area and destroy any other ships in the making, besides ferreting out the secret of the invisible substance and the elements of the gravity inverter. If we somehow survive, and this ship is destroyed, that's the next thing to do."
Jeter nodded and signaled Eyer to cease whispering.
They devoted their attention now to the six planes. They were coming up in battle formation. They were in plain view and through the telescopes it could be seen that each was armed with bombs of some kind. Useless against the invisible space ship as matters now stood; but what would those bombs do to the inner globe?
It still lacked several hours of the time allowed in the ultimatum to Jeter and Eyer of Sitsumi and the Three, when the six planes leveled off within a couple of miles of the space ship. They knew about where the stratosphere had swallowed up Jeter and Eyer. Now they were casting about for a sign, like bloodhounds seeking the spoor of an enemy.
Jeter and Eyer held their breaths as they watched. Now and again they stole glances at Sitsumi and the Three, who were watching the six planes with the intensity of eagles preparing to dive.