THERE must be as many reasons for divorce as there are grains of sand on the beaches of the world.

Yes, I do know the obvious and most frequent causes for break-up. But they are not quite what I have in mind.

It's not my actual intention to sue for a separation. Oh no, she-who-must-be-obeyed has done no wrong. Absolutely not - she is as innocent of wrongdoing as the day is long.

No. I'm the guilty party. It's me who has been acting unreasonably. And perhaps I should be grateful that her ineffable hugeness has decided not to take action on the grounds of unreasonably stupid navigational behaviour.

Navigation. What does it mean to you - Magellan circumnavigating the globe? Marco Polo bumping into China? Drake, Frobisher, the Apollo astronauts?

Let me tell you what it means to most people. Navigation is none of the above. No, the word conjures up images of the far more mundane.

It's getting from A to B in the car.

We'll never do this kind of trip again because it just doesn't work. From now on, it will be a case of travelling in relative comfort. No more long hikes across France or whatever with one driving... and the other navigating.

There are some things that, even if we lived to 100, could never be achieved. For example, I could never have worked in a bank. Which side of the brain is concerned with numeracy? I can't remember. See, I told you so.

Anyway, whatever lobe is relevant, in my case, this particular cerebral cavity is just an empty room with a single chair placed in the middle of the floor. Thankfully, I'm in the perfect career which, in some respects, is not really a proper job at all.

If I reincarnate, please dear God, may I be the same again, only with more hair next time. I promise not to make the same mistakes again.

So. We landed at Le Havre and my job was to find a village - note village, not bustling metropolis - called Vic-sur-Aisne. This scratch on the Gallic landscape is 80 miles east of Paris as the old l'oiseau noir flies and is not exactly on the beaten track.

Into centre ville and toutes directions, no problem. Keep an eye out for the A29 and... dum-de-dum, what a wonderful motorway this is to be sure, what with virtually no traffic about.

Mistake number one. This is a toll road, hence no traffic. There's four quid in francs to pay by the time we come off at St Saens but my troubles are only just beginning. For we are now in the middle of the French countryside and have left the A29 too early. Thanks to me.

So where are we now, barks the driver. Hmmm, there's a place called Buchy here, it looks as if it's in the right direction. The map is snatched from my hand by an increasingly impatient person a few inches to the right.

No, no, we need Forges-les-Eaux. Look, it's obvious! Are you an idiot or something? Look, I'm driving - you navigate!

Buchy. We arrive and there's a village fete being held, scores of gendarmerie and a new figure in the equation. It's a deviation or dee-vee-assy-on as they say.

Five minutes have elapsed and if I'd been given a franc for every time we'd driven up this farm track I'd have a fortune. It's boiling hot with the sun shining through the windows but it's bad nerves that are making me perspire. Fear, actually. For any moment now, she'll blow. This will be Krakatoa East Of Worcester and the detonation will make the old volcano look like a penny banger in comparison.

YOU IDIOT! Where's Bosc-Roger? Find it, you're the navigator. It's here. Come on, show me on the map. Point to it - do it! B-b-b-baa-be-baaa Bosc-Roger. Here. Look, give me a break, my eyes aren't that good these days. I think I'll have them tested for glasses when we return to England. This is not all my fault, honest.

Then whose fault is it then, eh? Mine? The gendarmes? The second artichoke from the left in that field over there? Heavens above - do the people in the office really know what a buffoon you are?

Nerves shot through, somehow or other, we take our leave of Buchy, although by now I feel I should stay and apply for the post of village idiot. Thank you, thank you God.

Forges-les-Eaux appears on the sign posts. Where now says meine kleine blumen. The name "Gournay" is half swallowed, half spat out, the joyful release of jubilation at actually getting something right.

Which road? Ah yes, it's the D21. No - the D145. Stop! Try the D919... no, no, that's the road back to Buchy, you halfwit. Where do we go from now - make your mind up, I need to know - NOW!

Aaah-eh gulp, the D21. Are you sure? Yes, yes. So the D21 it is and I thank my lucky stars as the distant spires of Gournay appear on the skyline.

The ordeal is relentless. Right, we need Beauvais now, rasps the red-eyed, demented she-demon at the wheel. Show me Beauvais on the map. The stutter returns, activated as if she had pressed a memory key on a computer keyboard. Baa-baa be-bop-alula Beauvais, yes, I really must see a speech therapist.

Here! Here! The finger jabs at the map. Move your finger, you idiot, I can't see it on the map, booms the beast from 20,000 fathoms. I can't see bloomin' Beauvais for your bleedin' stupid finger, she rants in a falsetto squawk that oscillates between tortured cockerel and banshee from hell.

The car kangaroos into Beauvais. The next town is Compiegne, and as that's a large brown splodge in an even larger green splodge on the map, it should be plain sailing. And yes, it's signposted.

It's as if the authorities know le stupide Philippe-Petit is due and they've laid on special measures for the more cranially-challenged travellers. And, praise be, the place where they signed the Armistice hoves into view. Any chance of an armistice in this car? No. It is not yet all quiet on the Western Front.

The river is now in sight, and just before the bridge, the sign for Vic-sur-Aisne is detected. There, that was fine, wasn't it? The driver stares straight ahead, clenched teeth betrayed by a twitching dimple appearing and re-appearing just above her jaw line...

Five days later. Middle-aged man writes postcard from somewhere in France.

"We're having a great holiday, wish you were here. Food great, weather not too bad, hope the rabbits are OK. Finding the campsite was a synch but I managed to do a good job with that old navigating lark. We are to set off home tomorrow but no worries. It's only a few miles to Le Havre, it should be easy. Cheers, all the best, John."