The bear-like figure out in the valley jerked at the bomb. There was a small rising cloud of grayish vapor. It continued. The figure climbed hastily out of the grid. When the man was clear, Bordman threw a switch.
There was a thin whining sound, and the wrapped, smoking object leaped upward. It seemed to fall toward the sky. There was no more of drama than that. An object the size of a basketball fell upward, swiftly, until it disappeared.
Bordman sat quite still, watching the control-board dials. Presently he corrected this, and shifted that. He did not want the bomb to have too high an upward velocity. At a hundred thousand feet it would find very little air to stop the rise of the vapor it was to release.
The field-focus dial reached its indication of one hundred thousand feet. Bordman reversed the lift-switch. He counted, and then switched the power off. The small, thin whine ended.
He threw the power-intake switch. The power-yield needle stirred. The minute grid was drawing power like its vaster counterpart, but its field was infinitesimal by comparison. It drew power as a soda-straw might draw water from wet sand.
Then the intake-needle kicked. It swung sharply, and wavered, and then began a steady, even, climbing movement across the markings on the dial-face. Riki was not watching that.
"They see something!" she panted. "Look at them!"
The four men who had trundled the smaller grid to its place, now stared upward. They flung out their arms. One of them jumped up and down. They leaped. They practically danced.
"Let's go see," said Bordman.
He went out of the tunnel with Riki. They gazed upward. And directly overhead, where the sky was darkest blue and where it had seemed that stars shone through the daylight, there was a minute cloud. But it grew. Its edges were yellow, saffron-yellow. It expanded and spread. Presently it began to thin. As it thinned, it began to shine. It was luminous. And the luminosity had a strange, familiar quality.