Earth hath not anything to show more fair:
Dull would he be of soul who could pass by
A sight so touching in its majesty:
This City now doth, like a garment, wear
The beauty of the morning; silent, bare,
Ships, towers, domes, theatres and temples lie
Open unto the fields, and to the sky;
All bright and glittering in the smokeless air.
Never did sun more beautifully steep
In his first splendor, valley, rock, or hill;
Ne'er saw I, never felt, a calm so deep!
Instead of focusing on polluted air, Wordsworth seems to embrace the beauty of the London sky. He is so immersed in nature, he longs to enjoy what he can see before the working day starts. It suggests that he is viewing the sky early in the morning before the workers start at the factories. 
 The  plosive  ‘b’, gutteral ‘g’ and percussive ’t’s unexpectedly suggest sharpness, rather than misty morning.
Composed upon Westminster Bridge September 3 1802