, but sat down to dinner. Johnson, as a pupil of the
doctor, tried to be a philosopher in the face of danger, but he
succeeded ill; his jokes stuck in his throat. Besides, they began to
feel uncomfortable; the air was growing bad in this hermetically
sealed prison; the stove-pipe drew insufficiently, and it was easy to
see that in a short time the fire would go out; the oxygen, consumed
by their lungs and the fire, would be replaced by carbonic acid, which
would be fatal to them, as they all knew. Hatteras was the first to
detect this new danger; he was unwilling to hide it from the others.

"So, at any risk we must get out!" said Altamont.

"Yes," answered Hatteras; "but let us wait till night; we will make a
hole in the snow that we may get fresh air; then one shall take his
place here and fire at the bears."

"It's the only thing we can do," said the American.

[Illustration]

Having agreed on this, they waited for the time of action; and during
the following hours, Altamont did not spare imprecations against a
state of things in which, as he put it, "there being men and bears
concerned, the men were getting the worst of it."

CHAPTER XIII.
THE MINE.

Night came, and the lamp began to burn dimly in the close air of the
room. At eight o'clock they made their final preparations. The guns
were carefully loaded, and an opening was begun in the roof of the
snow-house. Bell worked cleverly at this for a few minutes, when
Johnson, who had left the bedroom, where he was on guard, for a few
minutes, returned rapidly to his companions. He seemed disturbed.

"What is the matter?" the captain asked.

"The matter? nothing!" answered the old sailor, hesitatingly, "yet--"

"What is it?" asked Altamont.

"Hush! Don't you hear a strange sound?"

"On which side?"

"There! There is something happening to the wall of that room."

Bell stopped his work; each one listened. A distant noise could be
heard, apparently in the side wall; some one was evidently making a
passage-way through the ice.

"It's a tearing sound!" said Johnson.

"Without a doubt," answered Altamont.

"The bears?" asked Bell.

"Yes, the bears," said Altamont.

"They have changed their plan," continued the sailor; "they've given
up trying to suffocate us."

"Or else they think they've done it," added the American, who was
getting very angry.

"We shall be attacked," said Bell.

"Well," remarked Hatteras, "we shall fight against them.