"I'm doing the best I can," gasped out poor Harry desperately plying
his paddle.

It the canoe was to get broadside onto the current, even for the
fraction of a second, Frank well knew that nothing could save them.
It was a terrible situation.

Helplessly they were being borne at dizzy speed to what seemed
almost certain death--for certain it was that they could not hold
out much longer. Already their overstrained muscles were only
mechanically doing their duty, but before long Frank realized that
even his-well-trained young body must collapse--and then, what?

Suddenly there was borne to their ears a sound that made both boys
chill with terror.

It was a mighty roaring like the furious boiling of some giant
kettle. A thousand shouting voices seemed blended into one to form
the music, of this ominous orchestra. Louder the noise grew and
louder, as the pass through which the river now tore like a runaway
race-horse grew narrower and blacker.

What could the awful uproar mean?

They had not long to wait before the truth burst upon them. They
were nearing, at what seemed express speed, a whirling, roaring mass
of waters that shouted at them like some animal calling for its
prey. The boys' cheeks blanched as they realized that nothing but a
miracle could save them from being sucked into this watery abyss.