ART MARKET / Material challenge: Knickers on the line by Ay-O, a Beuys cello wrapped in felt - Charlotte Moorman, cellist and performance artist, left some extraordinary mementoes of the avant-garde

PERFORMANCE ART used to be a one-off affair; Jim Dine's The Smiling Workman, for instance, was a Happening, during which Dine drank jars of paint, poured them over himself and jumped through a canvas.

Performance art is nevertheless billed to take a bow in the auction rooms next week, when Sotheby's sells art works from the estate of Charlotte Moorman, the craziest cellist of them all. Under the influence of the composer John Cage, much of the performance art of the time grew out of music; Moorman herself discovered the avant-garde by performing Cage's compositions. She died at the age of 57 in November 1991, after fighting cancer with extraordinary courage for 13 years. She whispered the memorable one- liner to her husband, Frank Pileggi, on her deathbed: 'Don't throw anything out.' He didn't; all her papers and possessions are being painstakingly catalogued. This sale offers connoisseurs the chance to compete for her most striking art works.

Moorman was born in Little Rock, Arkansas, and trained as a classical cellist, attending the Juilliard School in New York. She was a member of the American Symphony Orchestra until the dark day in 1967 when she was arrested by the police for playing the cello 'partially naked'. She was topless and was engaged at the time in performing Nam June Paik's Opera Sextronique; Paik himself, who was also arrested, was performing the cello by kneeling in front of her holding the string over his naked shoulders. She was sacked from the orchestra as a result.

Moorman's involvement with the avant-garde began in 1963, the year she organised the first of 15 'Annual New York Avant Garde Festivals'. They weren't annual, of course; the last was held in 1980. They took place in a wide variety of venues ranging from Grand Central Station to the Staten Island Ferry, and gathered painters, musicians, actors, writers - all of them merrily mixing up their various media in structured and unstructured events.

Moorman herself adored performance and would take any risks for her art. Among the most memorable was a piece called Sky Kiss, composed for her by Jim McWilliams; it involved her playing the cello while suspended in a window-cleaner's harness from a helium balloon. She first performed it at the 1968 festival in Central Park. In another McWilliams piece of 1972, Ice Music for London, she performed naked on a cello made of fused ice-cubes - moulded into shape in a canvas cello case. It gave her frostbite.

According to her own account: 'It really was a good piece and I got so involved in playing that I'm not uncomfortable . . . it melted so beautifully . . . I loved every minute of it. The next day I am miserable, I am burning, my left breast is on fire, I'm suffering . . . So I went to the pharmacist. I couldn't tell him I've been playing an ice cello, you know, so I said to him: 'My husband and I were trapped in the Alps.' I said: 'We were exposed to ice and snow for many hours. Is there anything you can give me to help me?' '

The auction contains 17 separate lots, either art works that were given to Moorman by her friends or objects created by Moorman herself. It kicks off with a red banner painted by Ben Vautier, a language artist from Nice; his works usually comprise statements painted on canvas that examine the relationship of art and life. The banner reads 'Hey] did you know that art does not exist; all is Vanity (Ego)' and was displayed on the riverboat docked at New York's South Street Seaport - which was the venue for the 1972 Avant Garde festival. It is estimated to fetch pounds 3,000- pounds 4,000.

Then comes a stainless steel box measuring 2 1/2 x 2 1/2 x 2 1/2 inches made by Yoko Ono and titled A Box of Smile, estimated at pounds 1,000- pounds 1,500. It has a mirror in the bottom, so when you look inside you see yourself - and involuntarily smile. Yoko Ono and Charlotte shared a New York apartment in the early 1960s before either became famous. Yoko organised concerts which have been described as proto-Fluxus; Fluxus was the international movement that made avant-garde musical and multi-media performances famous.

A memento of Moorman's many collaborations with Nam June Paik - the Korean artist who has been dubbed 'the George Washington of video' and represents Germany at this year's Venice Biennale - is a collaboration between Paik and Christo entitled Wrapped Television. Christo, who is famous for wrapping things up - from the Pont Neuf to the Grand Canyon - has wrapped a portable television with transparent plastic and strong twine; it is expected to sell for pounds 25,000- pounds 35,000.

The financial climax of the sale, however, is Joseph Beuys's Infiltration Homogen fur Cello, estimated at pounds 200,000 to pounds 250,000. The short- lived German artist was regarded as a prophet and inspiration by a whole generation of younger artists, and mementoes of his performances now have a cult following.

Moorman's piece consists of a cello wrapped in grey felt with two strips of red felt pinned in the form of a cross on the front. It was made in 1975 for the only performance that Beuys ever created for an artist other than himself. He was introduced to Moorman by Paik while the two were on a European tour.

Earlier in the year, Beuys had wrapped a grand piano in grey felt and stitched a red cross to it. When Moorman performed Infiltration Homogen fur Cello, all she had to do was place the red cross on the felt cello. The red cross sigifies emergency, according to Beuys: 'the danger that threatens if we stay silent and fail to make the next evolutionary step'.

Other works include the Rainbow Banner, two washing lines strung with 23 women's pants and one vest, created by the Japanese artist Ay-O for the 1972 festival (estimate pounds 3,000- pounds 4,000); an Untitled umbrella frame hung with six mechanical musical instruments wired to four batteries and one set of metal wind chimes, made by Joe Jones in 1972 (estimate pounds 14,000- pounds 18,000); and Chamber Music by Takehisa Kosugi, a rubberised blue nylon bag with metal zippers inside which Moorman would perform, opening a zip from time to time to allow part of her own anatomy or the cello's to protrude

(estimate pounds 3,000- pounds 4,000).

Particularly moving are the art works that she made herself in recent years, all of them cellos. Her illness had made it hard for her to perform, but the creative urge had not died. There is Cello with Child, a Plexiglas cello enclosing a violin (estimate pounds 3,500- pounds 4,500),and Syringe Cello; Shadow of My Cello, a Plexiglas cut-out of the shadow of a cello densely collaged with hospital syringes (estimate pounds 4,000- pounds 6,000) - a harrowing reminder of her pain-killing medication.

When Charlotte Moorman died, the small flat on the southern tip of Manhattan that she shared with her husband (who was also the director of her festivals) was packed with mementoes. The valuer who had to appraise its contents for estate duty turned in confusion to Sotheby's for help. They saw an opportunity. The most saleable of the mementoes have been selected for auction; there are still medical bills outstanding.

(Photographs omitted)