Dawson, you do the talking!"

One of the pilots leaned tensely forward, his shoulders jerking. "We don't know, sir. The rotaries went dead when the ship started gyrating. We can't work the emergency torps and the temperature is rising."

"But--it defies all logic," Forrester muttered. "How could a metal ship weighing tons be suspended in the air like a balloon? It is stationary, but it is not buoyant. We seem in all respects to be _frozen in_."

"The explanation may be simpler than you dream," Lawton said. "When we've found the key."

The Captain swung toward him. "Could _you_ find the key, Dave?"

"I should like to try. It may be hidden somewhere on the ship, and then again, it may not be. But I should like to go over the ship with a fine-tooth comb, and then I should like to go over _outside_, thoroughly. Suppose you make me an emergency mate and give me a carte blanche, sir."

Lawton got his carte blanche. For two hours he did nothing spectacular, but he went over every inch of the ship. He also lined up the crew and pumped them. The men were as completely in the dark as the pilots and the now completely recovered Slashaway, who was following Lawton about like a doting seal.

"You're a right guy, sir. Another two or three cracks and my noggin would've split wide open."

"But not like an eggshell, Slashaway. Pig iron develops fissures under terrific pounding but your cranium seems to be more like tempered steel. Slashaway, you won't understand this, but I've got to talk to somebody and the Captain is too busy to listen.

"I went over the entire ship because I thought there might be a hidden source of buoyancy somewhere. It would take a lot of air bubbles to turn this ship into a balloon, but there are large vacuum chambers under the multiple series condensers in the engine room which conceivably could have sucked in a helium leakage from the carbon pile valves. And there are bulkhead porosities which could have clogged."

"Yeah," muttered Slashaway, scratching his head. "I see what you mean, sir."

"It was no soap. There's nothing _inside_ the ship that could possibly keep us up. Therefore there must be something outside that isn't air. We know there _is_ air outside. We've stuck our heads out and sniffed it. And we've found out a curious thing.

"Along with the oxygen there is water vapor, but it isn't H2O. It's HO. A molecular arrangement like that occurs in the upper Solar atmosphere, but nowhere on Earth. And there's a thin sprinkling of hydrocarbon molecules out there too. Hydrocarbon appears ordinarily as methane gas, but out there it rings up as CH. Methane is CH4. And there are also scandium oxide molecules making unfamiliar faces at us. And oxide of boron--with an equational limp."

"Gee," muttered Slashaway. "We're up against it, eh?"

Lawton was squatting on his hams beside an emergency 'chute opening on the deck of the Penguin's weather observatory. He was letting down a spliced beryllium plumb line, his gaze riveted on the slowly turning horizontal drum of a windlass which contained more than two hundred feet of gleaming metal cordage.