Eriss opened his eyes and sat up groggily. Then his gaze fastened on Joel. With a bellow of rage he was on his feet, charging across the room like a mad bull.

Three men, hanging onto the chain, snubbed him up short!

Eriss wheeled furiously, found himself facing half a dozen drawn paralyzers and brought up with a curse.

Joel could see the veins throb in the giant's temples. But the captain turned indifferently to the other prisoners. "Line up beside the chain."

Joel took his place between the black-haired girl and Nick Thorp. The collar was snapped about his throat. In single file and with a good deal of tripping, the prisoners, chained neck to neck, tramped through the door.

Doctor Chedwick left them at the main corridor, but the Captain and Mister Mullin helped the guards herd them into a lift.

They dropped soundlessly level after level until they were well below the surface. At length the lift stopped, the doors opened.

To his surprise Joel saw that there was a pneumatic station beneath the dome, and a train was waiting in the tube.

They were shepherded into a coach. They had a good deal of trouble arranging themselves in the seats because of the chain linking them together, but at last it was done.

Captain Goplerud blew a whistle and swung inside the car. The door slammed shut. With a powerful surge and a whoosh the train shot off.