"If part of the gas leaked out I don't see why it wasn't all set on fire and exploded," observed Captain Warner.

"It's a non-burnable gas," Tom quickly explained. "But come on. This may be our very chance. There seems to be something going on that may be in our favor."

Indeed the captives could hear confused cries and the running to and fro of many feet.

He made for the sawed panel, and, in another instant, had burst out and was through it, out into the passageway between the after and amidship cabins. His companions followed him.

They looked into the rear cabin, or motor compartment, and a scene of confusion met their gaze. Two of the foreign men who had seized the ship lay stretched out on the floor near the humming machinery, which had been left to run itself. A look in the other direction, toward the main cabin, showed a group of the foreign spies bending over the inert body of La Foy, the Frenchman, stretched out on a couch.

"What has happened?" cried Ned. "What does it all mean?'

"The lightning!" exclaimed Tom. "The bolt that struck the ship has knocked out some of our enemies! Now is the time to attack them!"

The Mars seemed to have passed completely through a narrow storm belt. She was now in a quiet atmosphere, though behind her could be seen the fitful play of lightning, and there could be heard the distant rumble of thunder.

"Come on!" cried Tom. "We must act quickly, while they are demoralized! Come on!"

His friends needed no further urging. Jerry Mound and the machinist rushed to the engine-room, to look after any of the enemy that might be there, while Tom, Ned and the others ran into the middle cabin.