BEVERAGE REPORT: THIS ROUND'S NOT ON ME

This is a message from your bank manager - if you're a fan of very old spirits, and you find yourself in the vicinity of Dukes Hotel, be careful. Dukes, London's most discreet five-star hotel, has a rather sumptuous list of ancient Cognac, Armagnac, single-malt and vintage port. And it also sells them at stupifyingly sumptuous prices.

The bar at Dukes is small, warm and cosy: "full of corners", explains Head Barman, Gilberto Preti, "because everyone wants a corner table." Preti and Andrew Phillips, the hotel's General Manager, regularly scout around for wonderful bottles to add to their collection. As you might imagine, the average off-licence can't help much.

"These bottles are very difficult to buy," says Andrew Phillips and, by definition, they get rarer all the time. Some come from specialist dealers, some from auctions, and many from private houses. "Because we are known for our interest, after specialising in this for a couple of decades, people sometimes bring in an old bottle they've found in the cellar and ask if it's worth anything."

When the answer is yes, it means serious money. At Dukes, malt prices range from pounds 12.50 for 1964 Tomatin (a mere infant) to pounds 45 for the 1936 Glengrant. Top prices in Armagnac reach pounds 77.50 for Vieil 1900. Cognac prices are most dazzling of all, starting at pounds 15 for 1972 Pianat and rising, at the moment, to pounds 125 for an 1811 Croizet. Top price ever was pounds 145 for an 1882 Fine Champagne Napoleon.

I will now say bluntly what they say at Dukes more tactfully. These prices are per glass. Repeat; per glass. It's not always easy making customers understand this, according to Gilberto Preti. Some assume the prices on the tariff are for a bottle. "We have to get that point across clearly, but discreetly, because you don't want to insult the customer."

Not every customer gets the point - or wants to get it. Gilberto Preti can usually tell when someone walks in whether they're going to ask for "something special" or not. "Many of those who do ask are regulars, perhaps industrialists who've just closed a deal and want to celebrate. They'll wash down their meal with a bottle of Chateau Haut-Brion or Petrus (or both), and finish by taking a trip to the bar. The bar bill alone can reach the pounds 2,000 mark."

Selling these drinks is profitable, naturally, but there is also a sense of loss when you're pouring from bottles that you know you will never see again. That 1882 Napoleon, which they had in a magnum, Preti describes movingly as their best bottle ever: "so beautiful and fantastic in its aroma. It breaks your heart when a bottle like this is finished." As if to prove the point, he fetches from the back room an 1838 Cognac which had been finished two nights before. Popping the cork, he sniffs deeply with a faraway look in his eyes.

But they do get finished, and at a rate that makes you wonder where all the money comes from. By the time you read this, the 1811 Croizet will be gone: they bought two bottles in July, and by 1 October the second bottle was down to a glassful. At sixteen measures per bottle, that's pounds 4,000 worth of Cognac.

I didn't leave Dukes with a notebook crammed full of tasting notes. A complimentary sampling session would have probably cost the hotel its profit for the week. But I did get to sniff a few bottles, and to taste a teaspoonful of an incomparably smooth 1943 Glenlivet (pounds 40 for a glass). If you want the full experience - complete with the ritual of warming football-size crystal goblets with boiling water before drying and polishing, then pouring in a generous measure of the liquid gold - you will have to pop along to Dukes. lt's in St James's Place, London SW1 (tel 0I7I 491 4840).

If you want to buy one of these bottles yourself, it can be done. With difficulty. Try the auction houses, or Top People's wine merchants such as Berry Bros & Rudd (0I71 396 9669) which may also have a small selection. At the time of writing, it has a 1924 Armagnac, J. Nismes- Delclou, at pounds 272. If you happen to be passing through Heathrow Terminal 3, you can grab a 1910 Armagnac, Baron de Lustrac at the Berry Bros duty- free for only pounds 600. Well, at least you get a whole bottle.

Are the sky-high prices at Dukes worth all that money? The question isn't worth asking unless you have vast reservoirs of personal disposable income. And even if you do, you might prefer to spend it elsewhere.

Those who spend it at Dukes go partly for the private-club atmosphere. When I was there, Gilberto Preti and his number two, Giorgio Guerra, greeted numerous customers by name. (One was a first-timer, a young American who had stopped in to pay his respects; his father's been drinking chez Preti for several decades.) And partly for the thrill of drinking something made before they were born. Before their parents were born. In some cases, before their great-great-great-great-grand-parents were born.

If I had pounds 125 to spend on drink, I'd probably pick a case of something rather than a single glass. On the other hand, Dukes currently has a glass of Otard Cognac (a favourite of mine) dating from the year of my birth. They're selling it for pounds 30 while stocks last. If I treat myself, I'll report back. !