But at last, "What's that?" exclaimed the man; for now a different tone resounded in the cataract, a louder, angrier note, as though the plunge of waters at the bottom had in some strange, mysterious way drawn nearer. "What's that?" he asked again.
Below there somewhere by the tenebrous light of morning he could see--or thought that he could see--a green, dim, vaguely tossing drive of waters that now vanished in the whirling mists, now showed again and now again grew hidden.
Out to the edge of the rocky shelf he crept once more. Yes, for a certainty, now he could make out the seething plunge of the waters as they roared into the foam-lashed flood below.
But how could this be? Stern's wonder sought to grasp analysis of the strange phenomenon.
"If it's true that the water at the bottom's rising," thought he, "then there must either be some kind of tide in that body of water or else the cavity itself must be filling up. In either case, what if the process continues?"
And instantly a new fear smote him--a fear wherein lay buried like a fly in amber a hope for life, the only hope that had yet come to him since his awakening there in that trap sealed round by sluicing maelstroms.
He watched a few moments longer, then with a fresh resolve, desperate yet joyful in its strength, once more sought the girl.
"Beta," said he, "how brave are you?"
"How brave? Why, dear?"
He paused a moment, then replied: "Because, if what I believe is true, in a few minutes you and I have got to make a fight for life--a harder fight than any we've made yet--a fight that may last for hours and may, after all, end only in death. A battle royal! Are you strong for it? Are you brave?"
"Try me!" she answered, and their eyes met, and he knew the truth, that come what might of life or death, of loss or gain, defeat or victory, this woman was to be his mate and equal to the end.
"Listen, then!" he commanded. "This is our last, our only chance. And if it fails--"