Vertical script tattoo down the back of the neck

You won't remember me at the back of Mr Okafor's chemistry room, the girl who copied the periodic table onto the inside of her pencil case. I remember you. You were the only one who laughed when the gas tap hissed and nobody else dared. Thirty-one years on, I still hear that laugh.

I have been trying to write this since Saturday, when you stood by the buffet with a paper plate of sausage rolls and told everyone the hall had shrunk. It hasn't shrunk. We grew. Nobody mentioned the ceiling, though, which still has the water stain shaped like Ireland that Dean Pryce swore he'd made with a catapult.

What I wanted to ask was about the notes you used to pass me in the margins of our exercise books, those tight vertical rows of letters that ran down the page like a fence. Nobody else could read them. I kept one from the lesson on tides, folded inside my atlas. Last night I took it out and tried to work out the alphabet myself, the way we did with the cipher on the coach to Whitby. I got as far as the first word before the kettle boiled and I lost my nerve.

Would you send me the key? Or better, come to the Crown on Thursday and read it to me slowly, the way you used to read out answers so the boys at the front could copy them wrong.

Yours, still in the back row, Hannah