An elaborate water fountain drips into a pair of antique drinks glasses, shaped like egg-timers. The pale green liquid in the bottom of the nearest glass clouds like a crystal ball.

After a few seconds, the cloud assumes strange shapes, like a genie in a bottle or a miniature green tornado, which twist and dance in the narrow neck of the glass.

The mysterious liquid in the eggtimer glasses is absinthe: La Fee Verte, the 'green fairy', the drink which fuelled (and some say ruined) a brilliant generation of French writers and painters in the 19th century.

This is not the poor imitation of absinthe created in the Czech Republic and Germany in the 1990s and marketed to gullible young clubbers.

This is the real thing.

One of the bottles in front of us is a 99-year-old bottle of CF Verger 'Suisse' absinthe, discovered a couple of years ago in a Corsican cellar.

Another is a bottle of 'Verte Suisse', a painstaking modern recreation of the original, distilled in France by a US chemist and marketed worldwide by an American former jeweller.

I try both. Both are extraordinary.

They are rich, electric and fresh, like drinking a malt whisky made from wild flowers.

My companion is Peter Schaf, 44, a former jeweller from Florida and Wisconsin, who married a French woman and came to live in France 12 years ago. After various ventures, he started a company called Liqueurs de France, which markets specialist drinks, and especially absinthe. His partner is Ted Breaux, 39, a chemist from New Orleans, who has analysed the contents of surviving bottles of pre-ban absinthe and cloned or "retro-engineered" three modern absinthe brands.

His company, Jade Liqueurs, sells 5,000 bottles a year for around 75 a bottle. Hold on a moment. Is absinthe not illegal, banned in France in 1915 as a danger to public morals and national survival? Is it not hallucinogenic? Is it not still as dangerous today as when it (allegedly) drove Vincent van Gogh to slice off his ear?

In the US, it is illegal to make it or sell it but you are permitted to own it or drink it. In France, thanks to an EU directive transposed into French law in 1988, the situation is as cloudy and as enthralling (and as French) as a glass of absinthe itself. You can make and sell absinthe so long as you don't call it absinthe but "extracts of absinthe".

Under the 1988 law, "new absinthe" must not contain the harmful substances which the old absinthe contained . . . except that, according to modern research, the old absinthe never did contain harmful substances in the first place.

"If you speak to 99% of French people, even well-informed French people, they believe absinthe is still banned in France, " said Schaf. "They still believe it is an evil drink, which drives you blind or crazy, or both.

They are wrong on the first count and they are definitely wrong on the second count."

Even if absinthe was never as harmful as calumny and legend insists, why revive it? Does the world not have enough hard drinks, without reinventing one?

"Mostly I am interested in the truth, " said Breaux. "It infuriated me that people could take some industrial alcohol and add green dye, as some of the 1990s absinthe makers did, and market it to crazy kids as a devil's drink which would make them 'see things'. We want to restore the reputation of the real absinthe, as a fascinating, delicious drink which, if you take in moderation, tastes like nothing else on the market."

Absinthe is the French word for wormwood (Artemisia absinthium), a plant in the daisy family which has medicinal properties but can be harmful and is reputed to be one of the bitterest-tasting herbs in creation. Absinthe, the drink, was created in Switzerland and the Doubs region of eastern France in the early 19th century.

Traditionally, it contained wormwood and green anise and different combinations of other herbs, fennel and hyssop. In the 1850s, the French wine industry was devastated by an aphid-like pest called phylloxera.

Most vines had to be replanted, making wine scarce and expensive.

Absinthe filled the gap, becoming the standard drink of all classes.

By the turn of the century . . . the Belle Epoque, when Paris was the artistic and literary centre of the world . . . the smell of absinthe pervaded France, but especially the world of artists and writers.

David Nathan-Maister is a British trader in antique and new absinthes, who runs the best absinthe site on the internet (www. oxygenee. com). He says absinthe was a victim of manipulation. "There never was anything dangerous about absinthe, so long as it was made properly and drunk sensibly, " he said.

By the end of the 19th century, the wine industry had recovered from the phylloxera infestation and wanted its market back. An unholy alliance formed between the wine lobby, the temperance lobby and conservative politicians who associated absinthe with bohemianism.

There are now several makers of reasonably authentic absinthe in France, Spain and Switzerland. However, Nathan-Maister believes Ted Breaux's 'Jade' absinthes are the only ones to get close to the taste of the original.