“Valve ten will hermetically seal every door and window,” explained Frank; “then lever six will open the sinking reservoir and we will go down.”
“Good!”
“If you are at all doubtful of the result, you shall witness the trial from the shore.”
“Never!” cried Stanhope, forcibly.
“All right, George.”
Suddenly the light in the cabin faded. There was a sinking sensation and all was deep gloom.
Then Frank shouted:
“Press key four, Barney.”
The Celt obeyed.
Instantly there was a flood of light in the cabin. Electric globes blazed in various quarters, and illumined the bottom of the tank as the boat reached it.