the glass walls as they turned to swim away. They sank about five
hundred feet lower; and all at once the lights went out, and the
boat gradually stopped.

It was at once so dark that the two captives could not see each
other, though only the width of the table separated them.
Everything was profoundly still; not a sound came from the
men in the other rooms. Presently Thorndyke whispered, "Look, do
you see that red light overhead?"

"Yes," said Johnston, "it looks like a star."

"It is our bonfire," said Thorndyke, "that's what betrayed us."

Again the vessel began to sink, and more rapidly than ever;
indeed, as Thorndyke expressed it, he had the cool feeling
that nervous people experience in going down quickly in an
elevator.

"If we go any lower," he added, as the great rubber hull seemed
to struggle like some living monster, "the sides of this thing
will collapse like an egg-shell and we will be as flat as
pancakes."

"You need not fear, we have much lower to go!" It was the
captain's voice, but they could not tell from whence it
came. Then they heard again the seductive music, and it was so
soothing that they soon fell asleep.

They had no idea how long they had slept, but they were awakened