came suddenly to the door. He was smiling as he motioned
toward the wines on the table.

"You had better drink more of the wine," he advised sententiously.

Both of the captives rushed to the table. The instant they had swallowed
the wine they felt relieved, but were still weak. The captain bowed and
went away. Thorndyke's hand trembled as he refilled his friend's glass.
"I thought I was gone up," he said, "I never had such a choky sensation
in my life; you are still purple in the face."

"Eat of what is before you," said the captain, looking in at the door;
"you cannot stand the increasing pressure unless you do."

They needed no second invitation, for they were half-famished. The fish
and meat were delicious, and the bread was delightfully sweet.

"Look outside!" cried Johnston. The water was now still, but it was
gradually rising up the sides of the boat, and in a moment it had closed
over the crystal roof. Both of the captives were conscious of a heavy
sensation in the head and a dull roaring in the ears. Down they went, at
first slowly and then more rapidly, till it seemed to them that they had
descended over a thousand feet. Great monsters like whales swam to the
vessel, as if attracted by the lights, and their massive bodies jarred
against 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 h