What happened after that seemed to pass like a terrible nightmare.

First there came a light cracking in the ice under their feet, but it was over in an instant.

Wabi was laughing at him for the fear that had come into his face, and calling his name, when with a thunderous, crash the whole mass gave way under them, and they plunged down into the black depths of the lake.

The last that Rod saw was his friend's horror-stricken face sinking in the crumbling ice; he heard a sharp, terrible cry from Mukoki, and then he knew that the cold waters had engulfed him, and that he was battling for his life under the surface.
Fiercely he struck out with arms and legs in an effort to rise, and in that moment of terror he thought of the great sheet of ice.

What if he should come up under it?
In which direction should he strike out?
He opened his eyes but all was a black chaos about him.