the balance when they crossed it. Thawed
around its surface, it had no cohesion with the ice on which it rested;
and, as a feather turns the scale, their crossing upon it may have
produced a motion, which resulted in its fall.

So vast a mass hurled into the great cleft, and acting as a driven
wedge, may have been the feather's touch that imparted motion to a
section of the glacier, already hanging upon the balance, and ready to
slide downwards.

Whether or not they had any agency in producing this fearful phenomenon,
our travellers reflected not at the time. They were far too much
terrified at the result to speculate upon causes. One after another
they mounted upon the great boulder, and satisfied themselves of the
facts that the crevasse had widened,--the bridge-rock had disappeared,--
and their retreat was cut off!

After a little, they ventured closer to the fearful chasm. They climbed
upon a ledge of the precipice, that gave them a better view of it.

From this elevation they could partially see into the cleft. At the
surface it was many yards wide. It appeared to be hundreds of feet in
depth. Human agency could not have bridged it. All hope of getting
back down the glacier was at an end; and with consternation in their
looks, they turned their faces away, and commenced ascending towards the
head of the ravine.

They advanced with timid steps. They spoke not at all, or only in low
murmuring voices. They looked right and left, eagerly scanning the
precipice on both sides. On each side of them towered the black cliffs,
like prison walls, frowning and forbidding. No ledge of any size
appeared on either; no terrace, no sloping ravine, that might afford
them a path out of that dark valley. The cliffs, sheer and smooth,
presented no hold for the human foot. The eagles, and other birds that
screamed over their heads, alone could scale them.

Still they had not lost hope. The mind does not yield to despair
without full conviction. As yet they were not certain that there was no
outlet to the ravine; and until certain they would not despair.

They observed the tracks of the musk-deer as they went on. But these
were no longer fresh; it was the trail of yesterday.

They followed this trail with renewed hopes,--with feelings of joy. But
it was not the joy of the hunter who expects ere long to overtake his
game. No, directly the reverse. Hungry as all three were, they
_feared_ to overtake the game;