"No one's firing, sir!" came the radio operator's voice. "There must be some mistake."
"Mistake—hell!" the captain roared. "I know anti-aircraft bursts when I see them!"
Dr. Duerkes made a mental note that a minute before Captain Hawes had called them air pockets.
The ship lurched again, then it bounced upward like a rubber ball. The whole craft seemed to be enveloped in a greenish cloud. A familiar, yet unidentifiable odor assailed the captain's nostrils. The motor coughed and died.
"Unloosen your safety belt," the captain ordered. "Get ready to bail out as soon as we get down where the air's thick enough to breathe."
The captain tried to start the motor again, but something was wrong with the supercharger.
"Must have been hit," he said.
There was a tinkle of glass and the air seemed to be sucked out of the cabin. Captain Hawes turned to see the cabin window falling out, but it wasn't that that made him turn pale.
Through the broken opening a greenish cloud was creeping into the plane. A long arm of vapor was extending itself toward the two men.