Having previously been cancelled and rearranged twice, the actual day of the second eye-operation arrives. I turn up, as instructed, at the Royal Free Hospital in Hampstead at 11.30am for a midday admission.

I now know the place so well that I’m getting to know various staff members’ anniversaries and their children’s names. This time, opthalmology buffs, I’m having a vitrectomy. The procedure involves some laser surgery, a new lens, and some readjustment of the detached retina which I had cryo-buckled last August.

Too technical for you? Okay then. From a DIY enthusiast’s perspective, try to think of it as some electronic chiselling, a bit of smoothing-out with a small rat-tail file, followed by a repositioning of the eyeball, which is then held in place with two tiny counter-sunk screws. Finally, they tap in a small plastic shim, to straighten it all up. That’s all there is to it. The human body – God’s own flat pack.

Honestly, you’ll be fine. The surgeon is a whizz. He works very fast, apparently. At this point I must recount a story which the Yorkshire chansonnier Jake Thackray used to tell on stage. He’d gesture at the guitarist in his band and say: “This one’s a proper musician. No, really. He’s that good. He’ll get to the end of the song long before the rest of us do, just you watch.”

I was unlucky. The last turkey in the shop. They finally trundled me into theatre at 7.30 in the evening. The process took about an hour. I was conscious for the whole procedure, having opted for a local anaesthetic.

I could hear the laser-work crackling like arc-welding in my head during the procedure. The light show was amazing, though, if mostly in monochrome. In younger, more psychedelic days I’d probably have paid good money for visuals like that.

They wheeled me out. A nurse gave me a whole carrier bag full of medications, far too many instructions to take in and a sheaf of paperwork. I found my way out, down the stairs and staggered into a now deserted reception area. Down the corridor a cashpoint glowed enticingly in the closed café. I also found a minicab sticker on a broken phone-point. I dialled it on my mobile phone.

You know when they ask you, before an operation: “Is there anyone who can meet you?” That’s why you should have someone there. Otherwise, you end up one evening on a north London street, with a carrier bag full of medicine, only one eye working, feeling faint and hoping that a taxi will come soon. What could possibly go wrong? Nothing, actually. He’s a good cabbie and when he sees the state of me with my bandaged eye, he is kindly.

In an earlier life he’d been a contract driver for the Labour Party. In his time he’d ferried nearly everyone. Mo Mowlam had been his favourite, along with Roy Hattersley. For some reason, he’d never really gelled with Mr Blair or Mr Brown. No, I didn’t ask.

London at night is rather different nowadays to the one which I once knew. In Old Street for instance, during my own gadabout evenings, there’d been not much going on there but the rent. These days, the pavements are thronged with pubby Londoners all puffing and guzzling for England. It’s 9.15pm and the traffic’s inching along, for all the world as if we were cruising Soho during rush-hour. Bright lights, big city and all that. It’s been reconfigured but it’s still there.

At Liverpool Street, I really begin to wilt. I find that I can barely read the electronic notice boards and now that the anaesthetic is wearing off, there’s a deep, nauseating ache behind my left eye. Somewhere around 9.30pm, I board a Colchester train. I didn’t expect it to be so busy. The carriage is almost full. I would estimate that about half of my fellow passenger are eating; stuffing their faces with hideously unfragrant franchise food.

The remainder are fiddling with, or bellowing into their mobile phones. As I sit down in my seat, two men gawp at my appearance. I stare back with my one good eye, until they look away. As people finish their food, they too, take to their phones. The train fills up still further at Stratford. Mercifully, at Romford it empties out to just under a humanitarian-crisis level. Further down the carriage, a bulky twenty-something, with a ticking iPod has spread himself out, his filthy be-trainered feet up on the seat opposite.

I do not know when England’s old peasant class disappeared, but someone should tell the sociologists that there’s a brand new one in germination right now. Semi-literate, greedy, loud, half-sozzled, ignorant and unmannered, you may meet them mid-evening on the rattling, uncleaned trains of suburban south-east England.

At 10.30pm, emerging into the cool night air of Colchester North, I swear could have kissed the holy platform out of sheer gratitude. And never was a man so glad to see a blonde of a certain age, standing at the ticket barrier with her car keys.