To me at my fifth-floor window
The chimney-pots in rows
Are sets of pipes pandean
For every wind that blows;
And the smoke that whirls and eddies
In a thousand times and keys
Is really a visible music
Set to my reveries.
O monstrous pipes, melodious
With fitful tune and dream,
The clouds are your only audience,
Her thought is your only theme!
William Ernest Henley
http://www.poemhunter.com/poem/to-me-at-my-fifth-floor-window/