Beech it was. And there’s something about rubbed-down beech. The wood is clean and hungry, each desk like an infant’s soul on which anything can be written. And I’m afraid some dark and dangerous part of me, my alter ego, did something he didn’t ought to have done.

It was in tiny letters and in dog Latin, because we did Latin at school in those days, and I wrote it on the virgin beech. I called the games master sadisticus illegitimusque, which roughly translates as mean bastard.

He must have fumed when he found it and grabbed a Latin dictionary. The rather poncey enclitic que (which I’d cribbed from the poet Catullus) would have properly foxed him. It’s a fancy way of saying and. Then the whole class was summoned back to the room, to stare at the desktops in front of them, to own up to anything they’d written there.

I stared at my graffito wondering, “Did I really write that?” I had conveniently forgotten. It was as if my alter ego, braver than I was, had written it, daring me on. I was forced to confess.

“Yes, sir. It was I who called you a bastard.” I remember the cold shower afterwards, being singled out on the football field - and extra, extra maths.

And I felt this brave alter of mine would do anything. He wouldn’t have snivelled at the top of our stairs as I had at 12, when I heard my father go through my maths and English books, going apeshit at my adding up and hopeless English grammar. My alter would have gone downstairs and hit him.

Since school days, my alter has been more subtle. In spite of, or maybe because of, my father, I’ve taken to writing.

Every other Thursday night I write 300 words under my grandmother’s maiden name, Daubney. Then I put on my Thursday night coat and hat and walk to the Hop Blossom. I order apint of London Pride, drink half and nod to the landlady, who puts it behind the bar. I walk to the local newspaper office, post the piece, then come back and drink the other half. “Here’s the other half of your Pride,” she says routinely, wondering who the heck I am. “See you in a fortnight.” I nod mysteriously.

I love my alter. He says such things. He writes about the ghastly town planners. The philistines who closed the local theatre. The trains. The old who moan about the young on the letters page. The local cobbler who wouldn’t put a battery in my imitation Gucci watch. One day they’ll discover my identity, translate me and give me a cold shower and the grown-up equivalent of compulsory games and extra maths.

Now I’ve come out, writing in The TES with a picture and a byline. But I have that same self-destructive urge to tell the truth.

Ssssh, reader, keep this under your hat. I’ve reached the high point of my teaching career. I don’t want my principal or the governors to know, but they are paying me when I’d gladly pay them for the privilege. I teach my own daughter A-level English literature. We are just about to start King Lear.

I shall read the part of the king. I am one of those old-fashioned performance teachers who hogs the best parts.

“I shall do such things,” I will threaten the class. The mad old king has been rejected by his daughters and is homeless on a windswept heath. “What they are, yet I know not, but they shall be the terrors of the earth!” She’ll be impressed by that. She’ll realise fathers must be treated with respect. She’ll be moved by the poetry and drama. She’ll realise what happens when you go against your father’s orders, that nothing comes of nothing.

Or will “I shall do such things, I don’t know what they are yet, but you’d better look out!” sound too familiar, the futile threats of an impotent fatherking teacher. And she’ll carry on in spite of, or maybe because of, her father.

Richard Hoyes teaches at Farnham College, Surrey. e-mail: richarddeaubenay @yahoo.co.uk