"That's what lots of people imagine," said the professor, "but except for the open sea, which I have proved does exist, I guess it's just as cold at the south as at the north, especially in the winter. We have struck the summer season."
"And a mighty warm one at that," observed Jack. "Whew! I've got to take off my coat."
Indeed it was getting uncomfortably warm in the ship, and the adventurers who had dressed in thick clothing to guard against the rigors of the icy climate, soon had to lay aside many of their garments.
"No wonder!" exclaimed Mr. Henderson, as he looked at a thermometer. "It is eighty degrees in here!"
"Worse than workin' in a hay field," observed Bill, as he wiped the beads of perspiration from his forehead.
"Let us see what sort of water we are traveling through," suggested the professor, as he again turned off the lights in the cabin so that a view could be had from the bull's-eyes.
Wondering what would meet their gaze the adventurers peered out of the small circular windows. At first they could hardly believe their eyes.
There, right before them, the sea was bubbling as if it was an immense tea kettle. Steam formed on the glass, and big clouds of vapor could be seen. The atmosphere of the cabin became almost unbearable.
"We are in the midst of a boiling hot ocean!" cried the professor.
"Are we sailing through hot water?" asked Andy.