Lonny grinned and went to the familiar seat. The craft was making larger circles as it descended, indicating that his guess must have been correct, that they were in a pocket, and that the pocket was broadening. Somewhere at the bottom of that pocket was a tunnel opening upon the outer ocean and it was up to him to find that opening--blindfold. If they could only keep descending until the vessel entered the channel their main problem would be solved. But if the pressure generated from the explosion was dissipated too suddenly, his mud-ship would ascend into the trap and stay forever there on the muddy ocean floor. He felt a lurch. The ship had paused and was sinking no longer. This then, was the limit. It would not go low enough. He saw the horror in Raeburn's eyes. They would die from starvation here. The gun in Raeburn's hands would be merciful, if it relieved them from the more hideous death that was certain to come. The hull shuddered, slipped against a rocky outer substance that seemed to give way suddenly. He felt the relaxation of the outer barrier through the controls, knew that the propellers were driving it out and into the true bed of the Uranusian ocean. The needle indicator paused uncertainly, started to rise. By the expression on Raeburn's face he knew that the other had not guessed that their trap was behind them. It was his chance. Lonny's hands moved swiftly on the controls. A surge of power sent the rear-drive mud-propellers spinning. Too much power. The ship tilted swiftly and Raeburn lost his balance. The man at the controls left them in a flash. Lonny seized the wrist that held the gun, wrenched it away. It went skidding across the floor. Then he stuck out fiercely at the sardonic features so close to him. Raeburn rocked backward, flailing out with both hands, as Lonny came in again, both fists landing solidly. His antagonist spun backward, then fell helplessly to the decking. Baron Munchy was jumping up and down in ecstacy. "Hit'm, Boss! Sock 'im again!" he piped, but Lonny picked up the gun, slipped it into his pocket, and shook his head in the negative. [Illustration: _"Hit'm, Boss. Sock 'im again!" Baron Munchy piped, jumping up and down in ecstacy. "Him all bad. Say Boss no good."_] "There's to be no more fighting, Raeburn," he said. "I'll pick you off with the gun if you start anything. When we break the surface you can get your mud-shoes and go." Four thousand feet. Three thousand. The mud-submarine was rising rapidly now, had passed the two thousand mark. "You've really hurt the little fellow's feelings," said Lana Hilton, evading his eyes and gesturing toward Baron Munchy, who was beating his fists against the wall in sheer frustration. "He must have been praying for blood and thunder." "I'll plaster 'im!" Munchy was squeaking. "I'll do him in!" One thousand.