Something a little different on this blog today: Wordsworth rather than Coleridge. But interesting, I think.
There, at the head of the post, is Canaletto's splendid painting ‘London: Westminster Bridge from the North on Lord Mayor's Day’ (1747).
There were several projects to build a bridge across the river at Westminster in the late 17th- and early 18th-centuries, all stymied by the Corporation of London, who wanted to preserve the rights and income of the barge- and ferrymen who worked the crossing. But eventually, in 1736, an Act of Parliament approved the project. Privately financed (including by a lottery), construction started in 1739 under the supervision of Swiss engineer Charles Labelye, who had invented a new technology, ‘caissons’ (sealed underwater structures supplied with air from above in which workman could dig the foundations for the bridge's piers into the riverbed). The bridge opened on 18 November 1750.
It was on this structure that Wordsworth stood, early in the morning of September 3rd 1803. From that vantage he wrote this very famous sonnet:
Earth has not any thing to show more fair:The date of composition is in the title of the poem.
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 splendour, valley, rock, or hill;
Ne'er saw I, never felt, a calm so deep!
The river glideth at his own sweet will:
Dear God! the very houses seem asleep;
And all that mighty heart is lying still!
Tamisi, regales qui praeterlaberis arces,
quam se magnificum, suspice, tollit opus!
quanto cum saxis coalescunt pondere saxa!
quo nexu incumbens sustinet arcus onus!
ardua quam iusto pendet libramine moles 
qua partes haerent partibus harmonia!
quos, cerne, ad numeros, ab utrovis litore sensim
sunt supra acclives alterutrinque viae!
pontis aperturae quam distant legibus aequis,
exterior quae vis interiore minor! 
hunc artis splendorem inter nihil impedit undas
quove minus placidus vel taciturnus eas.
nil tibi descensum accelerat; non vorticis ullus
impetus in praeceps unde ferantur aquae,
fluxu idem, refluxu idem, lenissimus amnis 
incolumem subtus sternis, ut ante, viam:
seris indicium saec'lis quo principe tanta
haec tibi surrexit gloria, liber eris.
O Thames, as you flow past regal citadels,
see what a fine structure has raised itself here!
With what heft does stone connect with stone!
How well the curving arch sustains its weight!
With perfect balance the tall structure hangs, 
its parts assembled with such harmony!
And see how, ranked upon either shore,
the rising paths each balance either side!
How equidistant are this bridge's arches,
the outer smaller than the inner ones! 
Through this wondrous art the unimpeded
river glideth calmly, silent onwards.
Nothing hurries your motion; no inrushing
whirlpool tangles the headlong current:
It flows the same, reflows the same, gently 
passing safely underneath the paved road.
Later generations will admire the prince
who erected so great a glory: you'll be free.