on,
was sleeping restlessly, when, at a waking moment, his attention
was attracted by a dull rumbling. He listened attentively, and
the rumbling seemed so strange that he nudged Jean Cornbutte with
his elbow.

"What is that?" said the latter, whose mind, according to a
sailor's habit, was awake as soon as his body.

"Listen, captain."

The noise increased, with perceptible violence.

"It cannot be thunder, in so high a latitude," said Cornbutte,
rising.

"I think we have come across some white bears," replied Penellan.

"The devil! We have not seen any yet."

"Sooner or later, we must have expected a visit from them. Let us
give them a good reception."

Penellan, armed with a gun, lightly crossed the ledge which
sheltered them. The darkness was very dense; he could discover
nothing; but a new incident soon showed him that the cause of the
noise did not proceed from around them.

Jean Cornbutte rejoined him, and they observed with terror that
this rumbling, which awakened their companions, came from beneath
them.

A new kind of peril menaced them. To the noise, which resembled
peals of thunder, was added a distinct undulating motion of the
ice-field. Several of the party lost their balance and fell.

"Attention!" cried Penellan.

"Yes!" some one responded.

"Turquiette! Gradlin! where are you?"

"Here I am!" responded Turquiette, shaking off the snow with
which he was covered.

"This way, Vasling," cried Cornbutte to the mate. "And Gradlin?"

"Present, captain. But we are lost!" shouted Gradlin, in fright.

"No!" said Penellan. "Perhaps we are saved!"

Hardly had he uttered these words when a frightful cracking noise
was heard. The ice-field broke clear through, and the sailors
were forced to cling to the block which was quivering just by
them. Despite the helmsman's words, they found themselves in a
most perilous position, for an ice-quake had occurred. The ice
masses had just "weighed anchor," as the sailors say. The
movement lasted nearly two minutes, and it was to be feared that
the crevice would yawn at the very feet of the unhappy sailors.
They anxiously awaited daylight in the midst of continuous
shocks, for they could not, without risk of death, move a step,
and had to remain stretched out at full length to avoid being
engulfed.

[Illustration: they found themselves in a most perilous position,
for an ice-quake had occurred.]

As soon as it was daylight a very different aspect presen