"A vessel afire?" proposed Mark.
"It's a fire on a vessel," said the professor, suddenly. "I believe that is the smoke of the trying-out works on a whaler."
"You've hit it, Professor," agreed Andy Sudds. "It's a whaler for sure.
There's more than you, Phineas, hunting for oil up in these regions."
"A whaling ship on this island in the air," murmured Jack. "What will they do with the whale oil? They will never get back to San Francisco again."
"We do not know that," said the scientist, gravely.
The last few miles, during which they could not see beyond the high ice-shod banks of the estuary, were traversed slowly enough. They all grew anxious to know what the column of black smoke meant.
Finally they came to the open mouth of this branch of the river. The sight they beheld almost stunned them.
Instead of an ocean, rolling up in great surges upon the beach on either hand, they beheld a vast sink through which the partly ice-bound river crawled as far as the eye could see. They knew that this was the old bed of the Arctic Ocean; but the waters of that cold sea had receded and left little but ice-bound pools here and there.
"Fo' de goodness gracious sake!" cried Wash. "Does yo' mean ter try ter mak' me beliebe dat disher place is whar' de great an' omniverous ocean once rolled? Dat de hugeous salt sea broke its breakers on dem ice-bound shores? Git erlong, chile! Yo' is tryin' ter bamboozle me, suah."
"That is where the Arctic Ocean rolled, all right," growled Phineas Roebach. "I can swear to that. I have been here before. Something has certainly happened to it."