spray leaps hissing out
of the fall, like a rocket, bursting in the wind and driven away in
dust, filling the air with light; and how, through the curdling
wreaths of the restless, crashing abyss below, the blue of the water,
paled by the foam in its body, shows purer than the sky through white
rain-cloud; while the shuddering iris stoops in tremulous stillness
over all, fading and flushing alternately through the choking spray
and shattered sunshine, hiding itself at last among the thick golden
leaves which toss to and fro in sympathy with the wild water; their
dripping masses lifted at intervals, like sheaves of loaded corn, by
some stronger gush from the cataract and bowed again upon the mossy
rocks as its roar dies away; the dew gushing from their thick branches
through drooping clusters of emerald herbage, and sparkling in white
threads along the dark rocks of the shore, feeding the lichens which
chase and checker them with purple and silver....

When water, not in very great body, runs in a rocky bed much
interrupted by hollows, so that it can rest every now and then in a
pool as it goes along, it does not acquire a continuous velocity of
motion. It pauses after every leap, and curdles about, and rests a
little, and then goes on again; and if in this comparatively tranquil
and rational state of mind it meets with any obstacle, as a rock or
stone, it parts on each side of it with a little bubbling foam, and
goes round; if it comes to a step in its bed, it leaps it lightly, and
then after a little splashing at the bottom, stops again to take
breath. But if its bed be on a continuous slope, not much interrupted
by hollows, so that it can not rest, or if its own mass be so
increased by flood that its usual resting-places are not sufficient
for it, but that it is perpetually pushed out of them by the following
current, before it has had time to tranquilize itself, it of course
gains velocity with every yard that it runs; the impetus got at one
leap is carried to the credit of the next, until the whole stream
becomes one mass of unchecked, accelerating motion. Now when water in
this state comes to an obstacle, it does not part at it but clears it,
like a race-horse; and when it comes to a hollow, it does not fill it
up and run out leisurely at the other side, but it rushes down into it
and comes up again on the other side, as a ship into the hollow of the
sea. Hence, the whole appearance of the bed of the stream is chan