HOW do you whistle, mummy? my five-year-old asked the other day. She had been watching Snow White and seemed fascinated by the Seven Dwarfs and the tuneful noise they made as they worked.

"Do you whistle at work?" she asked. "No," I said, thinking about how much I irritate my colleagues without subjecting them to a day-long session of Name That Tune.

"Who does whistle?" she asked -- a typical child, not letting the matter drop.

I thought about it and couldn't come up with anyone. Not the postman, nor the milkman, nor the window cleaner, nor the local beat bobby. Whistling has all but died out.

Even builders perched on scaffolding don't do it anymore. Their whistles have fallen victim to political correctness, after a handful of cases in which women took legal action after being regaled in such a way.

At least I like to believe that that's the reason, because I've been meandering slowly past a huge site near my home for weeks now, and not so much as a dickie bird.

I've been so upset by the lack of reaction -- how could they ignore such a gorgeous chick -- that I've started putting my anorak hood up on that stretch of road.

Even guards at the railway station don't whistle like they used to. Trains have those horrible hand-operated electronic buzzers.

And on the journey itself they have hooters and horns. In these days where we have to sand-blast fruit and veg before eating it, and when licking stamps and envelopes is seen as unhygienic, whistles are probably seen as a breeding ground for all sorts of contagious diseases. They' ve probably been outlawed under EC rule 35891-B

Although football referees still use them, I wouldn't be surprised if they were eventually replaced with some sort of synthesised air horn.

Apart from contestants on One Man and his Dog, my dad is one of the few people who still whistles as he takes a walk. He's very tuneful, and you can hear him a quarter of a mile away.

Perhaps the art is dying out because there are no whistleable tunes anymore. The stuff churned out by all those boy and girl bands doesn't really lend itself to whistling in the same way as the jazz hits that my dad reproduces so brilliantly.

And, let's face it, the youth of today would lose their street cred overnight if they hung around the bus stop whistling. Even those piercing, fingers-in-the-mouth jobs that children used all the time on the playing field when I was a schoolgirl, have died out.

If you want to attract your mate's attention 200 yards away, you text him. The last time I whistled -- four fingers, very shrill -- to attract a friend's attention, she looked horror struck, and turned to me, open mouthed, saying: "HELEN, was THAT you?"

It was only a couple of weeks ago, and I suppose it did seem an odd thing for a 40-something woman with a pushchair to do.

But I'm all for reviving the whistle. It's an activity associated with happiness. What with rail strikes, an ailing health service and the general state of disarray in Britain at the moment, the nation is obviously so morose that we never feel like piping up in this way.

I'm going to start a campaign to bring back whistling. Starting with the workplace.

The seven dwarfs have got the right idea. They seem happy enough, so in future I'll be sitting at my keyboard whistling. It will be interesting to see how long I can last before someone complains.