Analysis of Waterfall

Smooth to the shelving brink a copious flood
Rolls fair and placid: where collected all,
In one impetuous torrent down the steep
It thundering shoots, and shakes the country round.
At first, an azure sheet, it rushes broad;
Then whitening by degrees, as prone it falls,
And from the loud-resounding rocks below,
Dash'd in a cloud of foam, it sends aloft
A hoary mist, and forms a ceaseless shower.
Nor can the tortured wave here find repose:
But, raging still amid the shaggy rocks,
Now flashes o'er the scatter'd fragments, now
Aslant the hollow channel rapid darts;
And falling fast from gradual slope to slope,
With wild infracted course, and lessen'd roar,
It gains a safer bed, and steals, at last,
Along the mazes of a quiet vale.