Try as he could to repress it, a shout would force itself to his lips. So close were they to the steamer now, that one could plainly see the rivets in her tall, black sides. Tom even noted her name, North Star.
"Mr. Ironsides!" he cried, springing to the inventor's side.
Had the man gone suddenly mad? Did he wish to hurtle them all into destruction?
The professor, too, sprang forward.
"Great heavens!" he cried, "we will be dashed into eternity. I implore! I order! I insist——"
Swish-h-h-h-h-h-h-h-h-h-h!
A strange sound suddenly filled Tom's ears. The daylight was blotted out. The lights flashed up all through the diving boat. The floor tilted at a sharp angle, throwing the occupants of the conning tower once more into a confused mass.
While they were still in a swirl of confusion, the inventor's lean, claw-like hand shoved over a lever. The roaring noise ceased. The Huron resumed an even keel.
"We—we took a dive under that vessel?" gasped Tom, in a voice of incredulity.
"We did," smiled Obadiah. "You must forgive me for scaring you, but sometimes I feel like a schoolboy. I love to play tricks. I guess you thought we were going to smash into that ship's side."