When's the last time you heard a Kent Treble Bob, Stedman Triples or a Grandsire Major? They are methods of bell ringing heard only from bell towers such as those at the Washington Cathedral and the Old Post Office Pavilion. What's more likely is that you've heard a peal, the most famous bell ringing of all.

A peal? It's a symphony in a bell tower, change ringing straight from England, the gathering of dedicated men and women high up in a tower, each grasping a sally (a special grip) and rhythmically tugging on ropes more than 5,000 times. A peal takes at least three hours to complete.

Ringing isn't easy. It is a complicated numbers game, requiring manual dexterity and physical endurance. But with practice, the art is not beyond the reach of most people -- and it offers a great, and by and large unknown, source of enjoyment.

How does someone learn to ring, let alone discover the possibility? It was a combination of things for Meg Athey, who rang with the Washington Ringing Society until her recent move to Boston. After reading the Dorothy Sayers mystery Nine Tailors, featuring killer bells, the Smith College student signed up for a bell-ringing course. Not everyone would have had the luxury of exploring firsthand this unfamiliar musical mode, but Smith students can sign up for courses at their very own bell tower.

"Here was something I knew nothing about, and I needed to know," Athey says. "I started ringing the next week and that was it. It was like a new challenge. I liked the sound of it and it had a precision to it I liked, and there were a lot of nice people involved with it." Ten years later she's still ringing, and says she wouldn't live in a city she couldn't ring in.

A social as well as a musical pastime, change ringing brings -- and keeps -- a diverse group of people together. "Unlike an awful lot of hobbies . . . you can't do it by yourself. If you ring a bell by yourself, it's nothing . . . In ringing you're only as good as the worst member of the band," says Athey. And it may take years to become proficient at even the most common methods. As a result of this mutual dependence, the feelings of trust and reliance on one another in the Washington Ringing Society run high, as do reciprocal admiration and encouragement -- all necessary to keep the band harmoniously together.

A peal requires at least six people, each to handle a rope attached to a bell, which is mounted in a frame, fully equipped with wheels and pulleys enabling the bells to smoothly swing full circle. The ringing band stands in a ringing chamber, usually one floor below the bells, and, as if standing around an invisible fulcrum, each member pulls down on a rope, rhythmically following a set tempo, and then, with the control so essential, each eases up on the rope and the bells swing back around -- and ring.

The motion doesn't stop there; the ringers pull down and ease up, down and up, until the method -- a convoluted round -- is complete, usually anywhere from 10 minutes to 3 1/2 hours. As the ringers cannot see the bells, they maintain the rhythm by watching the position of the sallies, soft woolen grips woven into the rope, and listening for the ring of the preceding bell -- not an easy task when bells are ringing just seconds apart and their tones sound so much alike.

What seems at times to be a complete absence of even the semblance of order to the untrained ear is in fact the carefully composed ordering of numbers -- each bell a number -- and then their permutations. It's a fine art, honed by hundreds of years of practice and innovation.

"It really requires endurance and intense concentration," says John King, Washington Cathedral tower captain and a telecommunications lawyer in the District.

And time. King, who has been ringing for four years, still considers himself an intermediate.

Until 1964, only two rings of bells were active in this country, according to Richard S. Dirksen, bell master at the Washington Cathedral. Not that we didn't have the bells: those at Boston's Old North Church, where Paul Revere pealed as a member of this country's first active band and from whose tower the Minutemen were signaled that the British were coming, are probably the most famous. But those bells had been neglected, as were most of the other U.S. rings. The only two being rung were at the Groton School in Massachusetts and the Kent School in Connecticut.

But in 1964 bells were installed at the Washington Cathedral, an occurrence that contributed to the resurgence of ringing in this country, says Dirksen. Now there are about 25 bell towers actively being pealed in North America. Most are east of the Mississippi and in Canada. In England, where the cultic musical craft was born nearly four centuries ago, there are 5,000 bell towers.

Washington's newest bells are located in the Old Post Office Pavilion. The chamber is small, but modern; you can almost smell the fresh paint and putty. The bell tower was completed in 1983 after being built to accommodate the gift of bells from Great Britain. (The exact replicas of the Westminster Abbey bells were cast in Whitechapel Foundry, the very same that cast the Liberty Bell. Typical of this vocation dominated by tradition, Whitechapel Foundry has been casting bells since 1570.) Tower captain at the Pavilion is Cecily Rock, an attorney for a congressional committee.

The tower at the Washington Cathedral has a somewhat larger ringing chamber. This is the place the ringers are most used to, spend the most time at and use as a repository for their collection of bell-ringing books.

What is the attraction of this esoteric art, which can be done only high above the ground and in the company of only a select few? The answer certainly doesn't lend itself to generalizations. The 30 Washington ringers' professions vary, from student to scientist to clockmaker. The oldest is 61; the youngest, 17. And the lure of the bells runs from musical to mathematical.

"There are times when we ring a peal and so it goes on for a while," says Athey. "There's a kind of a magic time that sometimes comes in a peal.

"Peals are hard and it's a long time and it hurts and you have to concentrate for three hours." She pauses, remembering the time that her blistered hands hurt so much that she began to doubt her ability to go the 3 1/2-hour distance. If she failed, the peal would fail. The camaraderie of her fellow ringers kept her going.

"You have to be very alert and aware of making precise changes. Ringing takes so much concentration . . . But there have been times in some peals where it stops hurting. For some reason your hands just stop hurting, you just keep ringing, and it's as if one little part of your mind separates and says, 'Boy, this is nice.'

"It's only on certain occasions when we get a really, really good band together that we get that perfect ringing, but that's why people like me keep ringing after 10 years and keep teaching beginners."

R. Mark Mitchell, a Baltimore clockmaker, had wanted to learn to ring since he first heard the bells as a child. Now the 28-year-old enthusiast makes an 80-mile round trip twice a week to make his "childhood dream" come true. "Just listening to this does something to you," he says. "It's almost hypnotic."

Mitchell, who started in February, knows it will be a long haul before he'll be able to ring a peal.