"Where can we be?" asked Dave, rubbing a bruised head.
It was a strange sight which met their eyes as they looked from the conning tower. On every side appeared to be giant pillars of ice. Between these were narrow water passages, while above they could make out a mass of ice far more opaque than any they had yet passed beneath.
"One of two things," said the Doctor. "We are beneath an iceberg or the end of a glacier. Probably a glacier, and the pillars which support it reach to the bottom, which must not be far below us."
"We have driven between two pillars and stuck there like a mouse in a trap," said Dave, "and if we cannot set ourselves free, we are—"
"It must be done!" exclaimed the Doctor. "Start the power slowly and see what the propeller will do."
Dave gave the signal. There followed a harsh, grating sound, but the boat did not move.
"Stuck!" muttered Dave.
"Not so fast." said the Doctor. "There's hope yet. Shut off the power and order all hands aft."
"Now," said the Doctor, when they were assembled. "We will go to the starboard side, then all together dash to port, and throw our weight against the side. Then turn and rush back—we want to make her roll. Are you ready? Go!"
The craft stirred a trifle at the shock. The second attempt seemed to promise still better. After they had repeated the operation half a dozen times, they were getting considerable side-wise movement out of the trapped submarine.