As soon as Sitsumi had turned back to his station Jeter's lips began to move.
"See?" he said. "It isn't their machine guns these people fear. It isn't their bombs—it's their motors! I wonder why...."
By now the six planes were flying abreast, in battle formation, almost above the space ship, at perhaps a thousand feet greater elevation. A strange humming sound was traveling through the space ship. The whole inner globe was vibrating, shaking—and vibration was a menace to glass or crystal!
"We've got the answer!" said Jeter. "The outer rind, while capable of being softened—in sections at least, with safety—for special reasons, such as happened when we were 'swallowed,' can be hardened to the point of disruption. It can be shattered, Tema, by vibration! That's why the space ship keeps far above the roar of cities! The humming of countless automobile engines might shatter the rind! God, I hope this is the answer!"
In his mind's eye Eyer could picture it—the outer rind "freezing" solid, and cracking with the thunderous report of snapping ice on a forest lake. No wonder Sitsumi and the Three must destroy the six planes.
"Now!" yelled Sitsumi. "Shift positions! The space ship will be hurled directly at the formation of planes! Wang Li, to the beam controls!"
Wang Li sprang to the table, pressed a button. The humming sound in the space ship grew to mighty proportions. The trembling increased.
Jeter and Eyer kept their eyes glued to the six planes above. Without tilting their noses the six planes seemed to plunge straight down toward the surface of the space ship. Thus the two knew that the space ship was in motion—itself being bodily hurled, as its only present weapon of offense, against the earthling attackers.
A split second—