An instant later it seemed as if a hot wave had struck the Mermaid, or as if the craft had been plunged into boiling water.
“It’s going to be hot!” cried the professor. “Lucky I provided the water jackets!”
Then the lights in the interior of the ship went out, leaving the whole craft in darkness.
“What has happened?” cried Mark.
CHAPTER XIV
MANY MILES BELOW
“Don’t be alarmed,” spoke the calm voice of the professor. “I have only turned off the electrics. I want to switch on the search lights, to see if we can learn anything about our position.”
As he spoke he turned a switch, and, the gloom below the ship, as the boys could see by glimpses from the floor-window, was pierced by a dazzling glare. In the bottom of the Mermaid were set a number of powerful electric arc lights with reflectors, constructed to throw the beams downward. The professor had built them in for just this emergency, as he thought that at some time they might want to illuminate what was below the craft.
Not that it was of much avail on this occasion, for, though the lights were powerful, they could not pierce the miles of gloom that lay below them. The beams only served to accentuate the darkness.
“I guess we’ll have to trust to luck,” the professor said, after a vain attempt, by means of powerful glasses, to distinguish something. “There is too much fog and vapor.”
“What makes it so warm?” asked Mark, removing his coat.