The bed of the stream has been scooped out of the solid rock. Here and
there banks of sand have been deposited, and accumulations of loose
stone disguise the real nature of the channel. Great boulders have
been rolled down the alleyway and left where they chanced to stick; the
stream must get around them or under them as best it can. But there are
other places where everything has been swept clean; nothing remains but
the primitive strata, and the flowing water merrily tickles the bare
ribs of mother earth. Whirling stones, in the spring floods, have cut
well-holes in the rock, as round and even as if they had been made with
a drill, and sometimes you can see the very stone that sunk the well
lying at the bottom. There are long, straight, sloping troughs through
which the water runs like a mill-race. There are huge basins into which
the water rumbles over a ledge, as if some one were pouring it very
steadily out of a pitcher, and from which it glides away without a
ripple, flowing over a smooth pavement of rock which shelves down from
the shallow foot to the deep head of the pool.

The boy wonders how far he dare wade out along that slippery floor. The
water is within an inch of his boot-tops now. But the slope seems very
even, and just beyond his reach a good fish is rising. Only one step
more, and then, like the wicked man in the psalm, his feet begin to
slide. Slowly, and standing bolt upright, with the rod held high above
his head, as if it must on no account get wet, he glides forward up to
his neck in the ice-cold bath, gasping with amazement. There have
been other and more serious situations in life into which, unless I am
mistaken, you have made an equally unwilling and embarrassed entrance,
and in which you have been surprised to find yourself not only up
to your neck, but over,--and you are a lucky man if you have had the
presence of mind to stand still for a moment, before wading out, and
make sure at least of the fish that tempted you into your predicament.