Andy and Washington, who were watching beside the professor's bunk, where he reclined, seemingly in a deep slumber, were startled as he suddenly sat upright.

"Hark!" the old man exclaimed. "Listen! Do you hear it?"

"Hear what?" asked the hunter, in a soothing tone, wishing to humor the sick man.

"Do you not hear a terrible rushing, roaring wind? The ship! The ship is in danger!"

The thrilling words sent a chill to the hearts of the watchers. There was no sign of a storm. In fact it was strangely quiet outside, the only noise heard being that of the engines of the ship.

"His mind wanders," said Andy.

He had no sooner spoken than a cry from Jack, who with Mark was in the steering tower, startled them. His voice ran out through the cabins as he cried:

"A whirlwind! A whirlwind! We are running straight into a whirlwind!"

CHAPTER XIV

TOSSED BY A TORNADO