and a bed of clean hay, we could
sleep at Andregg's to-night, and be ready for a start in the morning
early."

"The very thing," said Dale. "How long will it take us to get from here
to Andregg's?"

"An hour," said the guide; "so we have several good hours before us to
go on up the glacier, or to cross over the valley ridge, and come back
down the next."

"Can we go up the glacier for another mile," said Dale, "and then
cross?"

"Easily."

"Then we will do that."

The ascent of the glacier-filled valley was continued, and they toiled
on. A mile on level ground would have meant a sharp quarter of an
hour's walk; here it meant a slow climb, slipping and floundering over
ice, splashing through tiny rivulets that veined the more level parts,
and the avoidance of transverse cracks extending for a few yards.
Sometimes they had to make for the left, sometimes the right bank of the
frozen river; and at last, as they were standing waiting while the guide
made his observations as to the best way of avoiding some obstacle in
their front, there was a sharp, clear crack.

"What's that?" said Saxe quickly.

"Stand back!" cried the guide. "No! quick--to me!"

They stepped forward to his side; and as, in obedience to a sign, they
turned, there was a peculiarly harsh, rending noise, a singing as of
escaping air, and to their astonishment, just where they had been
standing the ice began to open in a curious, wavy, zigzag line,
gradually extending to right and left. At first it was a faint crack,
not much more than large enough to admit a knife-blade; but as they
watched it slowly opened, till it was an inch--a foot--across, and then
all sound ceased, and they could look down for a short distance before
the sides came together, the whole forming a long wedge-shaped hollow.

"The opening of a crevasse," said the guide gravely. "It will go on
growing bigger, till it will be dangerous."

"You are lucky, Saxe," said Dale. "You have had a fall of rock, seen an
ice-cave and the birth of a big river, heard seracs fall, and now
watched the opening of a crevasse. We must have that avalanche before
we go back."

"When we get up on the ridge we shall see the Bluthenhorn," said
Melchior; "the afternoon sun will be full on the high slopes, and we
shall hear some of the ice-fall. Hark!"

He held up his hand, and they stood listening to a faintly booming
sound, evidently at a great distance before them.

"Was that one?"

"Y