'Shorts off, we plunged into the icy waters'

How do you do it? March right in and dive head first? Approach with extreme caution, moving so slowly that the icy water creeps up your body inch by inch - from ankle to knee and then (aaagh!) the groin - hands up in the air as though

How do you do it? March right in and dive head first? Approach with extreme caution, moving so slowly that the icy water creeps up your body inch by inch - from ankle to knee and then (aaagh!) the groin - hands up in the air as though waving for a lifeguard? Techniques for entering the water acquire ferocious urgency - indeed they feel like matters of life and death - when the water you are approaching is the Solway Firth. The first time I did it I looked around and noticed that all my friends were wearing wetsuits. Suddenly, floral Bermudas no longer seemed adequate. I got out when the pain in my fingertips spread to cripple my hands. That took about 30 seconds.

The trouble with having great friends on this beautiful, windswept coast is that sooner or later on every "summer" holiday you are going to have to swim. When that time comes there is no point shrieking like a baby or begging for mercy.

Not if your friends are like mine. They won't listen. They'll just plunge in, cosy in black rubber, and swim on their backs, laughing at you.

So when I went up there this summer I decided to get straight to the point. No messing about. The beers probably helped. We were on the way back from the only pub in the nearest village. The sky was clear and the night as warm as it gets in that part of the world, which is to say it was very chilly indeed.

I was looking forward to a stiff glass or two (with a hot chocolate chaser) when my friend, a native, pulled his car over to the side of the twisting lane and looked across to the reflection of the moon on the Firth.

"Look at that," he said, then, "Come on! We've got to go to the beach." It was nearly midnight, our bellies were heavy with pints of seventy shilling, and the drystone wall was huge. That didn't stop him. Over the wall he went, and I followed, laughing and half-protesting. The cowpats and potholes that would have been tricky in daylight were devilish in the dark, but thankfully there was a long slope to the field that hurried us down into the brambles and across the sharp, slabby stones to the beach.

It was gorgeous; the Islands of Fleet lying dark against the silvered water. My friend seemed happy to sit and admire the view, and maybe have a blether, but that wasn't enough for me. I had to go in. Sandals off then, cow dung oozing between my toes. Then the T-shirt, and the cold hug of the Scottish night around my chest. And before there was any chance to think again, shorts and pants down. "You're kidding," said Doug, who knows just how cold those waters can be, but when he saw that I was not, he stripped off too. There was no agonising about how to get in, just a couple of big, white backsides greeting the sky as we dived under. And a couple of screams soon afterwards. That was the impact of the water and the shock of the cold forcing air from our lungs, you understand. Nothing to do with the underwater realisation that every nerve was screaming and I was about to have a heart attack.

I know someone who works on the boats that chase a dolphin around a bay in the west of Ireland all summer, and every trip includes a warning not to go in and swim with the dolphin unless you are wearing a wetsuit. And every summer someone does so and dies. So aside from all the playful joshing - okay macho posturing - involved in going scuddy, as the locals call it, in Dumfries and Galloway at midnight, there was a fear somewhere at the back of my mind that this was it.

I surfaced and went dizzy and my feet frantically searched for the bottom, which was easy because the water was shallow. My friend and I flailed about, laughing to feel so very alive and not dead. Afterwards, we put our clothes on over wet skin and scrambled back up the hill, talking too loudly and thrilled by the tingle of our bodies warming up again. Central heating for big kids.

Since then, I have made a habit of watching people on beaches, and seen every kind of swimmer: the elderly woman who steps carefully across the shingle, barely able to walk, then enters the water without breaking the surface and swims like an Olympic champion; the "big dad" hurling insults at his little boy over his shoulder as he charges like a bull into the waves - only to run straight out again; and the pre-teens who splash about in the shallows for ever, throwing mud at each other and staying in until they turn blue and their teeth drop out.

Then there are the ones - men and women of all ages - you could suspect of wanting to extend the torture, so long do they take to get under. Try telling them, as the new owners of Knockbrex Castle told a travel writer, that "because of the Gulf Stream, the climate here is similar to the south coast of England. We even have palm trees in the gardens." They do, but they also have other kinds of trees which have been bent double and frozen into that position by the winds.

The Gulf Stream? When you're swimming in the Solway Firth and losing all feeling in your legs that sounds about as likely as my going for a midnight dip fortified only by Sodastream.