rrent was increasing each moment.

"We must endeavor to reach the bank and hold on to the branches of a
tree," he shouted in Spanish. "Down with your heads until the boat
strikes, and then try to lay hold of something."

There was no time for explanation. He seized an oar; a powerful stroke
swung the boat's nose round. By chance, he used the starboard oar.
All unknowing he spun a coin for life or death, and life won. They
crashed through some drooping foliage and ran into a crumbling bank.
Gray unshipped the oar and jammed it straight down. It stuck between
stones at a depth of three feet, and the life-boat was held fast for
the time. The canoes hurtled against each other, but were swept aside
instantly. When the noise ceased, they plainly heard the swirl of the
water. In their new environment, it had the uncanny and sinister hiss
of some monstrous snake.

"Everybody happy?" Gray demanded coolly.

"I am clinging to a tree trunk," answered Elsie.

"Bully for you. Make fast with a piece of rope. But be careful to
provide a slip-knot, in case we have to sheer off in a hurry. Can you
manage that?"

"Quite well."

Elsie was fully aware that the leadership of the expedition had gone
from her. She was not sorry; it was in strong hands. Suarez, too,
secured a stout branch, and passed a rope around it.

"Now, silence! and listen!" said Gray.

They soon detected a curiously subdued clamor from the inner recesses
of the cleft. At first almost indistinguishable, it gradually assumed
the peculiar attribute of immense volumes of distant sound, and filled
the ear to the exclusion of all else. It was like nothing any of them
had heard before; now it recalled the roar of a mighty waterfall, and
again its strange melody brought memories of a river in flood. But the
dominant note was the grinding noise of innumerable mill-stones. It
cowed them all. Even the dog was afraid.

"Guess we tied up just in time," exclaimed Gray, feeling the need of
speech. A little sob answered him. Elsie was beginning to admit the
sheer hopelessness of her undertaking.

"Now, cheer up, Miss Maxwell," said he. "All the water that is going
in must come out by the same road. At the worst, we can skate back the
way we came and take our chance. But it will soon be broad daylight,
and I'll answer for it that if Captain Courtenay is yet alive he is not
between us and the mouth of the inlet, or he would have contrived some
sort of r