When I behold a stream...

 The river at Pyrford Place,

where John Donne lived at the start of the 17th century

John Donne's sixth Elegy contains a remarkable landscape metaphor in which his inconstant lover is compared to a river that makes for itself a new course.

When I behold a stream, which from the spring
Doth with doubtful melodious murmuring,
Or in a speechless slumber, calmly ride
Her wedded channel's bosom, and there chide,
And bend her brows, and swell, if any bough
Do but stoop down to kiss her upmost brow;
Yet, if her often gnawing kisses win
The traitorous banks to gape, and let her in,
She rusheth violently, and doth divorce
Her from her native and her long-kept course,
And roars, and braves it, and in gallant scorn,
In flattering eddies promising return,
She flouts her channel, which thenceforth is dry;
Then say I; "That is she, and this am I."

There is another reference to erosion in Donne's most famous prose passage.  'No man is an island entire of itself,' he wrote in Meditation XVII.  'Every man is a piece of the continent, a part of the main; if a clod be washed away by the sea, Europe is the less, as well as if a promontory were.'  It is tempting now to misread these words in ecological terms, as temperatures rise and our coasts retreat.  We are all diminished by this process, even if we live far from the sea.  'Any man's death diminishes me,' Donne continued, 'because I am involved in mankind. And therefore never send to know for whom the bell tolls; it tolls for thee.'