cliff. Captain Lewis was leading the way one day, crawling along the
face of a rock wall, when he slipped. Only a quick thrust of his
spontoon into the cliff saved him from falling almost a hundred feet. He
had just struck it with terrific force into the rock, where it gave him
firm handhold, when he heard a voice cry, "Good God, Captain, what shall
I do?"

[Illustration: Tracking Up-stream.]

Windsor, a frontiersman, had slipped to the very verge of the rock, where
he lay face down with right arm and leg completely over the precipice,
his left hand vainly grabbing empty air for grip of anything that would
hold him back. Captain Lewis was horrified, but kept his presence of
mind; for the man's life hung by a thread. A move, a turn, the slightest
start of alarm to disturb Windsor's balance--and he was lost. Steadying
his voice, Captain Lewis shouted back, "You're in little danger. Stick
your knife in the cliff to hoist yourself up."

With the leverage of the knife, Windsor succeeded in lifting himself back
to the narrow ledge. Then taking off his moccasins, he crawled along the
cliff to broader foothold. Lewis sent word for the crews to wade the
margin of the river instead of attempting this pass--which they did,
though shore water was breast high and ice cold.

[Illustration: Typical Mountain Trapper.]

The Missouri had now become so narrow that it was hard to tell which was
the main river and which a tributary; so Captain Lewis and four men went
in advance to find the true course. Leaving camp at sunrise, Captain
Lewis was crossing a high, bare plain, when he heard the most musical of
all wilderness sounds--the far rushing that is the voice of many waters.
Far above the prairie there shimmered in the morning sun a gigantic plume
of spray. Surely this was the Great Falls of which the Indians told.
Lewis and his men broke into a run across the open for seven miles, the
rush of waters increasing to a deafening roar, the plume of spray to
clouds of foam. Cliffs two hundred feet high shut off the view. Down
these scrambled Lewis, not daring to look away from his feet till safely
at bottom, when he faced about to see the river compressed by sheer
cliffs over which hurled a white cataract in one smooth sheet eighty feet
high. The spray tossed up in a thousand bizarre shapes of wind-driven
clouds. Captain Lewis drew the long sigh of the thing accomplished. He
had found the Great Falls of the Missouri.

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