ke was able to point to a
break in the sheer wall on the Dry Mesa side, where the precipices
were set back one above the other in a Cyclopean stepladder and their
steeply-pitched faces were rough with crevices and shelves.

"Look!" he cried. "There's the place--there's our ladder up from hell
to heaven!"

Ashton soon lowered his weary head. He stared dully downstream to
where a fifty-foot cliff extended across from side to side of the
canyon like a dam.

"Part of the wall slid in," he stated with the simplicity of one who
is nearing exhaustion.

"That shall be our bridge to the ladder," shouted Blake. "It's all
sheer cliff along here at the foot of the break, but the ledges run
down sideways to the top of the cross cliff. We shall soon be lying up
there, high and dry, getting our second wind for the run up the
ladder."

The engineer spoke confidently, and felt what he spoke. But as they
struggled on down the turbulent stream to the cross cliff, the light
left his face. From wall to wall of the canyon the great mass of fallen
rock stretched across the bottom in a sheer-faced barrier, broken only
by a tunnel barely large enough to suck in the swelling volume of the
river.

Blake came down close to the intake, scanning every foot of the cliff
face for a scalable break or crevice. There was none to be found. He
climbed along the cliff foot to a low shelf beside the roaring tunnel,
and stood staring at the opening in deep thought. Even while he
looked, the swelling volume of the river filled the tunnel to its
roof. Blake peered at the fresh watermark twenty feet up the face of
the cliff, and bent down beside Ashton, who had stretched out to rest
on the shelf of rock.

"There's only one thing to it, old man," he said. "We must dive
through that tunnel."

"Through that hole?" gasped Ashton. "No! I've done enough. I shall
stay here."

"To drown like a rat in a rainwater barrel!" rejoined Blake. "Look at
that watermark. The tunnel is now running full. Inside a quarter-hour
the river will be up over this ledge. It will keep rising till it
reaches that mark, and it will not fall until after low water."

"What do I care?" said Ashton hopelessly. "Go to the devil your own
way. I'd rather drown here than in that underground hole. Leave me
alone."

Blake considered a full half minute, looked up the cliff face, and
replied: "Perhaps it's as well. I shall do the best I can. But first I
want to tell you I've wiped out al