Has anyone else seen the penises on Westminster Bridge?

Well, you should - because on a fine afternoon in London, when the sun is low in the sky to the west, a strange and wonderfully puerile phenomenon occurs that might just cheer you up in these depressing times.

The metal panels on the west of the bridge have a cut out motif, featuring hundreds of shamrock-shaped holes with three equally sized leaves: one at the top in the middle, one each at the bottom to left and right.

But when the low sun is angled just so, the shape of one of the leaves becomes elongated so that it forms a point shaped like a phallus, while the other two retain pretty much their original shape and so look like a pair of testicles.

Thus a nice little meat and two veg ensemble is projected onto the pavement of the bridge, quite literally under the feet of the passers-by, and right next to the august cradle of democracy that is the Houses of Parliament.

It was my wife Cath, a scientist by training and a saucy bird by inclination, who made this important and serendipitous discovery a little while back, while crossing the bridge from one routine work meeting to another.

She immediately started corpsing at the startling sight of the multitude of willies spread out before her and - as she was walking alone - looking around desperately for someone to share the joke with her.

Alas, there was no-one to respond to her increasingly frantic nods, gurns and winks, except - inevitably - some bewildered foreign tourists, to whom she couldn’t explain the joke.

So she contented herself - like you would - with jumping carefully on all of the cocks like a girl playing hopscotch. Or, worse, like an intra-office email she once received from a work colleague showing a woman’s foot in a red stiletto shoe stamping repeatedly on a surprisingly erect and resolutely excited member. I ought to add that the missus was definitely wearing sensible, flattish shoes at the time she crossed the bridge.

Cath has also convinced herself that, despite the Victorians’ reputation for prudishness, the penis effect of the metalworking is completely intentional and meant to be a joke shared by succeeding generations.

In which case, the name of the Victorian architect Sir Charles Barry, FRS, (1795-1860), must come into the frame.

Sir Charles, who was responsible for the Gothic-style detailing on the bridge and significant parts of the Houses of Parliament - might be argued to have a bit of previous in this regard.

His Wikipedia entry (you can see I have done my research thoroughly) says: “The…plaque marking Barry's tomb in Westminster Abbey shows the parts of the Palace of Westminster (he) had strongest claim to, and this is seen by some as Barry's cry for recognition from the grave.”

So might not the willies, then, be a gag from beyond the grave by one of our most eminent architects? One that is - commendably - still making us laugh almost 150 years after his death.

Certainly, now that we have discovered it, I feel Barry’s joke presents Britain with a legacy - a money-making opportunity which should not be ignored.

Now we are deeper in recession than most of our European cousins, and that the Euro-Sterling exchange rate makes us an attractive place to visit, why not encourage the continentals to visit London and the Muy Famoso Ponte do Catsos (The Bridge of Cocks, if you’re not as fluent as moi)?

I mean, The Bridge of Sighs and the Ponte Vecchio are all right. But, given the right sunshine conditions, and an appropriate PR and translation budget, I think the comprehension gap that stymied my wife can be bridged easily enough.

William Wordsworth - another dead artist who can’t therefore complain about this output being traduced in this way - once wrote a poem about the view from an earlier Westminster Bridge that could be harnessed to the money making cause.

“Dull would he be of soul who could pass by/A sight so touching in its majesty,” he wrote in 1802, which I think would look really classy on a marketing brochure for London’s Bridge of Cocks.

Indeed, there is something so universally funny about the sight of all those old men magically spread out before us that we need to think big, as it were.

Our esteemed visitors from abroad might eventually give the Bridge Formerly Known as Westminster a pan-European, even a world profile.

I mean, it can’t fail to be better than the Manneken Pis, which almost everyone who has been to see it would surely say is rubbish.

Anyway, the Manneken Pis has one extremely small willy. We have scores of large, sunlit members to set against it or, to plunder another Wordsworth poem, “a host of golden (penises).” Makes you proud to be British, doesn’t it?