What it was that happened when he felt the waters swiftly rising all about him Grenville could never have told. He was almost certain his foot had come in contact with a heavy, pulpy surface, like a wet thing made of rubber, as he did his utmost to strike his assailant with his heel.

He could only be certain that he seemed to plunge downward interminably, and that afterwards a horrible rush of waters, lashed to violence, was sounding wildly in his ears and confusing his staring eyes.

Then he came to the top with a sickening conviction, that one of his legs would be gone almost before he could feel the incisions of the teeth where the shark was closing upon it. He lurched tremendously forward in the water, to close the short but vital gap between himself and the ladder.

It seemed to him then a nightmare must be binding his limbs to inaction—that incredible time was elapsing while he still remained in the tide. As a matter of fact, he had moved with prodigious energy, his strokes and velocity through the water phenomenally swift. And, when he caught at the lowermost rung, he shot from the depths like some weirdly living projectile, doubled up in a knot by its speed.

For his knees were drawn sharply upward, and hand over hand he scaled up his swaying support. But his ears heard the hiss where that terrible fin was cutting the waves beneath him. One quick glance he sped to the place comprehended the turning monster's belly, the open mouth, and even the hideous nose that shot beneath his very foot like the point of a speeding torpedo.

To the round above he scrambled no less galvanically—only to feel a sudden giving of the ladder. A wild conviction of the structure's insecurity above—its giving way beneath the incautious strain he had unavoidably put upon it—scorched its way into his brain, while he still looked down upon the shark.

But that one slip ended as abruptly as it had come. It was all in the rung he had clutched in desperate violence, and not in the ladder itself. Elaine's rock anchorage was firm!

A swift and weakening reaction now ensued in all his being, as he clung there, dripping but safe. He leaned on the ladder-rung heavily, to regain his breath and strength. He was panting and all but exhausted for the moment. When at length he resumed the upward climb, the shark was no longer to be seen.

He paused a bit longer on the shelving ledge above to gather his wits in proper order.

"Sidney!" he heard. "Are you coming? Are you there?"