UNDER CERTAIN CIRCUMSTANCES, there are few hours in life more agreeable than the hour dedicated to the ceremony known as afternoon tea," wrote Henry James in 1880.

And probably nowhere can the ceremony be more delightful than in London's elegant 19th-century Mayfair hotels.

I had not realized that the custom performed as routine in the drawing rooms of Jane Austen and Oscar Wilde still existed, but my British landlord and his wife assured me it did and that I must try it. Try it, I did, and soon found that I had become nearly as addicted as the Duchess of Bedford. This 18th-century lady unwittingly set a tradition by suffering a sinking feeling around 5 p.m. and requiring tea and cakes to revive her.

Tea time in many London hotels is from about 3:30 to 6 p.m. and the cost is from $3 to $4. Although this may seem high, the "set tea" includes tea with all the accessories, delicate finger sandwiches and meltingly rich pastries - all this, of course, served in sumptuous surroundings.

To my mind it is well worth it and epitomizes what is most appealing about the British experience - taking time for an unhurried conversation in an elegant and refined atmosphere.

Afternoon tea is also a way to spend a couple of hours in some of London's most exclusive hotels without spending $60 a night for a room or a large bill for a fancy meal. It's less frantic than grabbing a cocktail in the bar. The lounges where tea is served have a certain hushed charm.

In my perusal of several hotels, it seemed that Mayfair, bordering on fashionable Old and New Bond Streets, was the most appropos for afternoon tea. Tea, then, can be combined with shopping or strolling by Sotheby's, the world-famous art auctioneers; Carter, the jewelers; or one of the many art galleries or boutiques with such discreet names as Celine, Christina and Hubert.

Also, right off of Bond Street is the Victorian Burlington Arcade with its wood and glass store fronts enclosed in an archway of fancy plaster molding.

My favorite hotels for tea were narrowed down to four - the Ritz and Brown's (my top choices) and Claridge's and the Connaught, both running a close second.

When Cezar Ritz opened the Ritz on Piccadilly in 1906 (the first Ritz in the world), he wanted an atmosphere that had the best of France in an English country house setting.He certainly achieved this in the magnificent cream, gold and pink rococo decor of the Palm Court.

For a tea with a friend, the Ritz has been and still is the place. You ascend a marble staircase flanked by columns into a fantastic garden-party world of mirrored paneling, gold statuary, marble tables, potted palms and pink powder-puff-colored Empire chairs.

The $4 tea is served from 3:30 to 5:15 p.m. Sandwiches include cucumber, salmon, tomato, cream cheese and chive and cheddar cheese with sprinklings of watercress. From the lavish dessert cart there are eclairs, glazed tarts with custard and cakes layered with whipped cream. I chose a sponge cake of whipped cream and strawberries and my friend, a chocolate sponge layered with chocolate whipped cream.

The decor is so intricate and varied that after two visits I still feel I haven't begun to savor it all. Most intriguing is the textured pink glass ceiling surrounded by white beams embossed with gold fret work. Chandeliers that hang like huge gilt bird cages are decorated with enamel roses and daisies, and creamy cupids trail garlands of pink roses along the ceiling's edge.

Although ornate, it is never cloying, and the acoustics are such that while not actually hearing another conversation, there's a pleasant sound of hushed whispering. Each time I've descended the marble staircase of the Palm Court, I've felt a twinge of melancholy to leave such a perfect, delicate world.

If I were to go for tea alone or with a companion who prefers a down-to-earth atmosphere, I would choose Brown's on Albermale Street.

Outside it's a warm, mild chocolate color with white trim and inside it's filled with gleaming oak paneling. Tea from 3:30 to 6 p.m. is in a lounge with deep armchairs and sofas, and nooks and crannies that give a feeling of privacy. It seems the kind of place upper-class detective Peter Whimsey of the Dorothy Sayer mysteries would frequent.

Brown's was reconverted from 17th- and 18th-century homes in 1847 by James Brown, a gentleman's servant. His wife, Sarah, had been maid to Lady Byron, the wife of the poet. Solid comfort prevails. In the lounge, along with a few couples, there were several people alone. One particularly content young man in a pin-striped suit was reading the "Tales of Raz" in between puffs on his pipe and sips of tea.

The $3.25 tea includes tea in the traditional heavy metal pot with a slimmer one with hot water to dilute the tea to preference. Three plates are brought to the table with finger sandwiches of egg, tomato, herring and ham, buttered wheat bread and delicious hot buttered scones. A fourth plate has several pastries. We had an eclair and an apricot tart, but if the pastry desired is not on the plate we were told to ask, for it may be available in the kitchen.

Such varied personages as Queen Victoria, Theodore Roosevelt and Rudyard Kipling visited Brown's. Eleanor and Franklin Roosevelt spent their honeymoon there in 1905. And one year later, Alexander Graham Bell felt such rapport with the then-owner that he made the first British telephone call to him from a room at Brown's.

A grand, stately home feeling pervades Claridge's on Brook Street. A liveried footman in top hat and tails ushers guests in through the revolving door and another up toward the reading room where tea is served from 4 to 5:30 p.m.

Queen Victoria visited Claridge's in the mid 1890s, and was so impressed she recommended it to her relatives. Now, Queen Elizabeth II books guests at the hotel and it was the stopping place of Jacqueline and Ari Onassis when they visited London.

Off the foyer is a grand staircase of ornate wrought iron where royal guests descended the morning of Queen Elizabeth's coronation in 1953. The silk wallpaper in the reading room is a pale green with silver birds and was made specially for Claridge's. It highlights a crystal chandelier and pillars of green marble with gold capitals that divide the room in half.

An enormous bouquet of fresh flowers sits on a table with ornately carved legs in the center of the room and pastries are on a silver platter on a small bow-fronted table. The $3 tea is brought by a waiter who first sweeps a white linen tablecloth onto the table and then immediately reappears with a platter of cucumber, egg, tomato, herring, ham and bacon sandwiches that he leaves on the table. Sandwiches finished, he returns on cue, it seems, with a platter of chocolate and coffee eclairs, cream puffs and glazed fruit tarts.

Claridge's is the place to visit to experience service with the kind of flair that royalty appreciates.

In "Stories of Great Hotels," Christopher Matthew writes that in London only the Connaught on Carlos Place can be compared to a large, comfortable private home. Built in 1896, the brick hotel has all the dignity of Claridge's, but not the formality. It is smaller, with just over 100 rooms, and curves gracefully around Carlos Place onto Mount Street. Perhaps most indicative of the home-like feeling are the small wooden benches on the porch and the magnificent solid mahogany staircase that ascends to all of the hotel's six floors.

Tea is from 3:30 to 5 p.m. in a small lounge with rose carpeting, white lacy curtains, set off with bright green drapes and pink and green armchairs. Like Brown's, it is divided into nooks - a particularly charming one enclosed under a plaster moulding of a gray scallop shell.

Behind white pillars along the back is an idyllic wall painting of barges floating down the Thames in the 18th century. A convenient key points out the location of such famous places as St. Paul's Cathedral. Pink linen covers the tea tables and the tea pot gleams with the kind of perfection you'd expect of a home where the silver is polished daily.

The $3 tea included only tomato, egg and cucumber sandwiches, but a large selection of pastries. Especially good was a pastry layered with fresh strawberries and whipped cream.

After tea we wandered happily around the hotel and particularly liked the wood-paneled bar.

We felt the Connaught's friendliness when a waiter invited us to inspect one of the private dining rooms. We were obviously not in the market to rent one at $80 per person but wanted to see as much of the hotel as we could. The Connaught logo is "placere placet" - it pleases to please - and it did seem to apply.

Afternoon tea is served, too, in many of London's fancy department stores. Harrod's on Knightsbridge and Fortnum and Mason's on Piccadilly are particularly known for fine afternoon teas.

Although some may not like to spoil appetites by eating sandwiches and pastries at 4 p.m., the food aspect of afternoon tea isn't necessarily what is most important and you can just order tea.

Or, then again, you may find as James did in 1880. "There are circumstances in which whether you partake of the tea or not - some people of course never do - the situation is in itself delightful."