the ice, he was striving to look over the lip of the schrund. Stampa,
feeling a steady tension, must be expecting the announcement
momentarily that Barth was crossing the narrow crevice at the bottom.
Helen and Karl, intent on the operations of the leader, paid heed to
nothing else; but Spencer was fascinated by Bower's peculiar actions.

At last, Barth's deep bass reverberated triumphantly upward.
"_Vorwaertz!_"

"_Vorwaertz_, Stampa!" repeated Bower, suddenly changing the ice ax to
his right hand and stretching the left as far along the rope and as
high up as possible. Simultaneously he raised the ax. Then, and not
till then, did Spencer understand. Stampa must be on the point of
relaxing his grip and preparing to descend. If Bower cut the rope with
a single stroke of the adz, a violent tug at the sundered end would
precipitate Stampa headlong into the crevasse, while there would be
ample evidence to show that he had himself severed the rope by a
miscalculated blow. The fall would surely kill him. When his corpse
was recovered, it would be found that the cut had been made much
closer to his own body than to that of his nearest neighbor.

"Stop!" roared Spencer, all a-quiver with wrath at his discovery.

Obedience to the climbers' law held the others rigid. That command
implied danger. It called for an instant tightening of every muscle to
withstand the strain of a slip. Even Bower, a man on the very brink of
committing a fiendish crime, yielded to a subconscious acceptance of
the law, and kept himself braced in his steps.

The American was well fitted to handle a crisis of that nature. "Hold
fast, Stampa!" he shouted.

"What is wrong?" came the ready cry, for the rear guide had already
driven the pick of his ax into the ice again after having withdrawn
it.

Then Spencer spoke English. "I happen to be watching you," he said
slowly, never relaxing a steel-cold scrutiny of Bower's livid face.
"You seem to forget what you are doing. Follow me until you have taken
up the slack of the rope. Do you understand?"

Bower continued to gaze at him with lack-luster eyes. All he realized
was that his murderous design was frustrated; but how or why he
neither knew nor cared.

"Do you hear me?" demanded Spencer even more sternly. "Come along, or
I shall explain myself more fully!"

Without answering, the other made shift to move. Spencer, however,
meant to save the unwitting guide from further hazard.

"Don't stir, Sta