THERE'S THE RUB! The cathedral center (open daily, 9:30 to 5) provides everything a beginner needs, including instruction, for $3 to $30. Brasses range from six inches to well over six feet, and price depends largely on size. A hint: Start with a brass with a well-raised edge as smooth a surface as possible. Size is no indication of degree of difficulty. Small comfort: If rubbing marks stray outside the edge, they are erasable.

She had been struggling with the pleats and folds and hem of the heavy gown most of the afternoon, but there was still no telling how it would turn out. Christine's neck was stiff, her right arm sore, her chin smudged. Still, she carried on. Just three of four more swipes now -- "uh, oh," rip. Well, maybe three or four more. Lady Margaret Peyton just smiled, forgivingly, the smile she's been smiling for 500 years now.

It's to be a Christmas present," said Christine, 11, as for the tenth time she smoothed the glossy paper that covered Lady Margaret from her starchy headdress to her pointy slippers. Another stroke with the beeswax, a final gentle flourish, and the brass rubbing was finished.

There, in all her courtly splendor, was Lady Margaret -- the "Lace Lady," as she's come to be called -- just as she wanted to be remembered when her brass funeral effigy was laid down in an English parish church in 1484.

"My mom taught me how to do it," Christine said, pointing across the Washington Cathedral crypt to a trousered woman trying to work waxier definition into Sir William Fitzralph's waistcoat. Hard by her elbow -- for an instant -- is Ann Etches, a flash of Lacoste green darting among rubbers waxing away at Sir Humphrey of Blatherick, Squire Holveston of Blickling or Lady Maud of Bray, Berkshire.

"I see you're a beginner," she says to one. "No, I wouldn't try that one." To another: "No, of course you don't have to be an artist." She guides the neophyte on a difficult bit of tracery.

Etches, who with her husband, Richard, founded the cathedral rubbing center three years ago as an extension of one in London, is among the dozen or so leading experts in this country on the art, history, technique and so-what of brass-rubbing.Still, she finds it hard to explain exactly why hundreds of people are drawn to the crypt each week to make waxy black impressions of long-dead Englishmen.

"I think," she began, in her "just outside London" accent, "they feel they've created something of value and beauty that they can frame or hang as is. Everyone leaves here with a sense of accomplishment, satisfaction."

More important to most rubbers in the intimacy they feel with history -- a life they can examine caress, get their fingers into in a way that's impossible with a painting. "There was a blind woman in here last week," Etches said. "Her grandchildren brought her. She did a wonderful rubbing -- that brass over there. She worked a long time on the face."

High-born Englishmen began having themselves modeled in memorial brass in preference to permeable stone or wood in about the middle of the 13the century. pThe practice, gratifying piety and vanity in equal parts, and spurred by a new method of brass-working, swept town and manor. Over the next three centuries thousands of brasses were commissioned -- Knights of the Bath and Garter, fully armed and armored; richly robed merchants surrounded by doting wives and children; praise-God clerics and scholars in attitudes of final prayer.

The permanence they hoped for was vain, however, as revolution, Reformation, neglect and the growing popularity of brass-rubbing took their toll. Fewer than 500 original English funerary brasses exit today -- almost none of them available for rubbing, so fragile and cherished have they become. Happily, an English printer invented a process 12 years ago to make copies almost indistinguishable from the original. Now dedicated rubbers have access to images that had been vaulted away for decades or centuries. The cathedral center has about 50 brasses on hand at any one time -- exchanging them periodically for others from the London center, the largest in the world.

All are copies, of course, but so nearly perfect that even Lady Margaret couldn't tell for sure.