It says "I think I am it. If you are too, come to South Quay DLR". One would guess that it has been painted by one who has have fallen in love with another on the way to work and harbours the belief that love is reciprocated. My grasp of graphology is good enough to know the writer is male so we can assume HE followed the beloved (gender unknown) and left a message where he knew they would see it - probably on the way home. It is rather strange because it would seem far more effort to do all that than to just go up to the person in question and start talking to them. But love know no logic does it?
There is of course a noble tradition of romance on bridges - right back to Dante getting his first peek at Beatrice on the Ponte Vecchio in 1300 and dedicating his life to her honour. Their love was never consumated of course - I believe she thought him somewhat of a wimp and there was always a Mrs Dante and some mini Dantes waiting for Dad back at home.
London provides endless scope for the romantic imagination - yet another reason not to live in the country I would have thought. This is particularly true when you are falling into or being pushed out of love. The city is soaked with the stains and traces of love lost and love found: particular districts become associated with a particular person or a particular time; a broken heart can lend significance to the most ordinary of bus stops; an intensity of feeling amplify some dismal corner to the level of that bridge in Florence. Holborn tube reeks with the scent of a million assignations.
Such urban love can make fools of us. For a while I couldn't deal with West Kensington at all and found even buying a ticket for the district line poignant yet Dalston retains a certain romantic air in the imagination in spite of its grubby appearance. Once lost in some amorous madness, I saw a man walk through the wall of Russell Square tube, a sun-lit stream flowing through a concrete car-park behind Grays Inn Road. There is a bench in Soho square I have not been able to sit on since a friend told me he had sex on it ...with my ex. For months, I was absolutely convinced a certain person was about to turn into the street ahead of me and things would be alright. They never did, and now I am glad of it.
I wrote a song about such things a while ago. It was released with Joe Coles singing - but here is the orginal with yours truly.
As for our friends on the bridge above, It is conceivable that they may be together now. Or perhaps the wrong person read the message and turned up and it all worked out anyway. That would be a nice ending to this story - but if they are together or even if they are not, I hope someone remembers to come back and clean the pavement - just in case.