Mr. Chancellor at the Algonquin bar in New York, before Amsterdam’s influence set in.

I am much embarrassed to reveal that in 60 years I have never tried pot. I remember about 30 years ago being at a supper party in Rome when the person next to me at table passed me what I thought was a lit cigarette. I have always been very fond of cigarettes, but not of the damp, half-smoked ones of people I donÕt know. I thought this one looked unhygienic and might carry some disease.

All the same, not wanting to be rude, I accepted the cigarette and took a small puff. I was immediately revolted by its sickly smell and hastily passed it on, realising that the stuff inside it was obviously not tobacco but marijuana. I resolved never to touch the weed again, and until this week, it was one of the few resolutions I have ever kept. But the Sunday Telegraph has been my downfall. With the bait of a luxury suite in Blakes, Anouska Hempel’s snazzy new hotel in Amsterdam, it persuaded me to spend a night of depravity in the cannabis capital of the world.

Knowing practically nothing about the drug I consulted the American National Institute of Drug Abuse, which has a page on its website entitled “Marijuana: Facts Parents Need to Know”. “Marijuana is a green, brown, or gray mixture of dried, shredded leaves, stems, seeds of the hemp plant (Cannabis sativa),” it began. “All forms of cannabis are mind-altering (psychoactive) drugs; they all contain THC (delta-9-tetrahydricannabinol). MarijuanaÕs effect on the user depends on the strength or potency of the THC it contains.”

So, come what may, my mind would be altered; but how was I to know which of the hundreds of kinds of cannabis legally available in Amsterdam would be the safest for me to try? “At all costs, you should avoid “skunk,” said one of my godsons. “It is ten times stronger than ordinary hash and has names like AK47 and Mindblaster.” Being an ecologically-aware young person, he also disapproved of “skunk” because it was genetically modified and grown in greenhouses. So I should go instead for “weed” (African bush weed, they might call it).

And how would that alter my mind? “It could make you a bit paranoid,” was the reply. “It can make you think everybody thinks your stoned. Also, your eyes can go bloodshot. And it can make you thirsty and crave sweet things ‹ this is called having the “munchies”. But it can enhance creativity.” Martin Amis, when I bumped into him at a party last week, didn’t agree. It would probably just make me want to go to my hotel room and watch television, he said.

When I called my daughter Cecilia to ask her for advice, she just said: “Dad, don’t drink too much.” Others had already told me that it was bad to drink alcohol before smoking a joint, it could make you pass out ‹ but Cecilia may just have been reflecting a commonly-held view among the young that drinking is generally much worse for people than pot-smoking. She also knows that I am a traditionalist whose vices are of the old-fashioned kind.

The Sunday Telegraph had said that I could take a companion with me to Amsterdam, and I chose my older brother John, another traditionalist but much less fearful than me of new experiences. He is also a gregarious fellow who doesn’t mind whom he engages in conversation, a quality I thought could be useful in the many coffee shops of Amsterdam, which I had imagined (wrongly, as it turned out) would be full of rather scary characters.

What the Dutch call “coffee shops” are the places where cannabis is legally bought and consumed. They look outwardly like ordinary cafes and in most respects are. But they are also shrines to the culture of cannabis, with countless varieties on sale for consumption on or off the premises. You make your choice from “menus” – books even heavier and grander than the wine lists of expensive restaurants – in which hundreds of kinds of the noxious substance are listed, with photographs or even actual samples of them glued to the pages beside their names.

Amsterdam is probably how Ann Widdecombe imagines Hell. Tolerance of soft drugs is not “zero” there, but absolute. Anybody can legally possess up to 500 grammes of cannabis, a whopping amount. They can grow it in their window boxes. They can buy it in shops. They can smoke it in the street. The only places where it is not welcome are normal bars, cafes and restaurants where cigars and cigarettes still reign supreme.

Whatever the bad effects of soft drug legalisation, it has certainly achieved one thing. It has banalized cannabis. There is no glamour in taking it any more. You can ask anybody in the street where to find the nearest coffee shop, and even the solidest citizen will give you directions in a matter-of-fact way. Yet only this week the European Union revealed that many more 15 and 16-year-old children use cannabis in Britain, where it is an offence, than do in Holland, where it is not, 37.5 per cent here compared to 31.1 per cent there. The banalization may have something to do with it.

When we arrived from the airport at Blakes, I asked one of “the young, elegant staff clad in black designer suits” (I quote from the hotel’s publicity material) whether I could order cannabis from room service. He looked a little surprised, but said he was sure it would be possible. However, we thought we would waste no time and took a taxi to the first recommended coffee shop on our list, the Bluebird.

This was the beginning of a long coffee shop crawl during which many joints were smoked, so my memory has suffered a little. But the Bluebird was in what appeared to be a very respectable quarter of old Amsterdam. There was nothing about it to suggest decadence apart from a notice in the window saying that children under 18 were not allowed inside. There was a comfortable room with a bar upstairs in which three or four men with ear-rings or long hair were puffing away rather dolefully.

The person in charge was a pale young man with magnificent hair like the wig of King Charles II. I approached him at the bar and told him I was new to this game and needed advice before getting started. “Have you never had cannabis before?” he asked, without any show of surprise. “No, I haven’t,” I said. “Well I will tell you what I always say to first-timers,” he said. “Do not be surprised if it does nothing for you at all. You may feel good, but on the other hand, you may feel nothing.”

I secretly liked the idea of feeling nothing, but feared that the Sunday Telegraph might be disappointed. “What should I do if I feel nothing?” I asked. “Try something stronger?” “No, I don’t think that would be wise,” he replied. “Just come back tomorrow and keep trying. You’ll feel something in the end.” But we had only 24 hours in Amsterdam; so if I was going to feel anything, it had better be sooner than that.

The man rolled two joints, one for me and one for my brother. Mine was called Moroccan Pollen, I think, but I didn’t know what John’s was. All I knew was that they were both supposed to be mild. Then we sat side by side on a sofa while the photographer Andy Hall, who had accompanied us from London, started snapping away at us with his camera. I hold Andy largely responsible for the coughing fit that followed. Like all professional photographers, he wanted to take endless photographs of the same scene ‹ in this case, of me lighting my joint with a cigarette lighter and inhaling ostentatiously.

He made me repeat the same performance again and again in rapid succession until the inside of my mouth felt as if somebody had been at it with a cheese grater, my throat was sore and dry, and my coughing was brutally puncturing the woozy, dream-like atmosphere into which the other customers had settled. “How do you feel?” Andy asked. “Not tremendously good,” I said.

John, meantime, was doing rather better. “I feel quite agreeable,” he reported. Then, after little while, he became silly. “It’s delightful here,” he said. “This place sums up the whole world. The whole world is in here.” I looked around. Three Russians from New York, a young man and two girls, one of them rather pretty, had joined us on our sofa.

The pictures on the walls were of frogs and crocodiles and fairies, suggesting psychedelic visions. A blond man with an ear-ring and an evil-looking smile was standing goofily against the wall. But in every other respect the Bluebird looked to me like a pretty ordinary caf/. Having taken against my own joint, I borrowed John’s and started to feel happier. I asked the man with the Charles II hair what it contained. “Skunk,” he said. “Oh, no! Not skunk!” “It’s very weak skunk,” he assured me.

We decided to move on to another coffee shop up the street called Happy Hour, which had a sign outside it offering “Smokes and Jokes”. The boss of Happy Hour, who said he was called Haile and came from Surinam, rolled us “white widows”, whatever they are, to a background of loud reggae music. Then he joined us at a table for a chat.

Haile was an amiable chatterbox. He started expounding on the art of using cannabis. “You don’t just smoke it. You don’t just inhale it. It’s an art, a way of life. You have to live it. You have to be it. That’s the secret.” John was beginning to look as if he’d mastered the secret. I certainly had not. I was beginning to think I would like to go to my hotel room and watch television. But that was not to be.

There was a final coffee shop on our list, the Grasshopper, which had been suggested to us as an example of a large establishment, unlike the cosy little places we had visited so far. As we walked there, I found myself feeling rather giddy and tottering a bit. I wasn’t enjoying what I imagine to be a “high”, but at least I wasn’t feeling nothing.

The Grasshopper was lacking in any charm ‹ just a large underground room in which dozens of dull-looking people sat at rows of tables arranged in tiers all facing the bar, as if it were a cinema screen It was midnight and I had had enough, so we found a Spanish restaurant still open in the Red Light district and ate Spanish omelettes before going to bed. I was too tired to watch television.

Next morning, to my surprise, I was feeling fine. Before leaving for the airport, we paid a visit to The Hash Marijuana Hemp Museum on a pretty old canal street beside the Sensi Seed Bank Grow Shop for grow-your-own enthusiasts. Containing, among much else, a live indoor marijuana garden, this peculiar museum devotes one display to Queen Victoria’s medicinal use of the plant and another to the notorious British drugs smuggler Howard Marks, whose story, it says, is “full of excitement, humour and charm”.

According to the museum, cannabis use is very old indeed. In 450 BC, Herodotus apparently wrote about the pleasures of the “cannabis bath” and the billows of steam and smoke it produced. “No Greek vapour bath can in any way surpass it,” he maintained. “The Scythians howl with joy when having a cannabis bath.

I would like to try one.

October, 2000