Should you be looking at the River Ouse between Ouse and Lendal bridges and spot a musician floating over the water in a giant bubble as big as a house, at any time from 9pm to 10pm tonight, you are not already the worse for wear after a skinful on the Micklegate run.

What your are observing is not a re-enactment of a scene from the cult television series The Prisoner, but Music Of The Spheres, part of the 2002 York Colourscape Festival.

Suspended exactly in the centre of the 25ft-diameter transparent sphere will be a flute player, 13ft above the water, lit by searchlight, playing music to be relayed to loudspeakers on buildings around the dockside.

Let festival organiser Simon Desorgher explain all: "The Sphere is a transparent inflated globe created by Colourscape artists Peter Jones and Lynne Dickens, who have made several sizes of spheres for different events. The one we'll be using in York is the size of a small house and is one of the largest inflated spheres ever created," he says.

"The Sphere will be inflated on a specially-built stage, and the flute player in concert clothes of black tail coat will enter the globe, ascend a rope ladder and be harnessed into the centre.

"The Sphere will be launched on to the river as the flautist performs, and then move in a strange ballet on the water, sometimes towering over the audience, sometimes moving into the distance."

As for the 25-minute performance, is it a New Age alternative to Handel's Water Music? "The Music Of The Spheres represents the harmony of the spheres and the ancient Greek elements of Earth, Air, Fire and Water," says Simon, who happens to be the composer - and flautist.

"Tonight this unearthly music will spiral and spin around the onlookers, the sound being sent via radio to a complex computer system on the dockside, where it will be processed by computer maestro Lawrence Casserley to become an orchestra of flutes, to be broadcast from nine loudspeakers that represent the sun and the planets."

The giant bubble spectacle launches the 2002 York Colourscape Festival, a "magical world of music and colour" that will be held in the Museum Gardens from tomorrow until August 11 in a new Colourscape built for York with National Lottery heritage funding.

"It's the only music festival to take place within a sculpture," says Simon. "The new York Colourscape maze has been designed specially for the Museum Gardens and is nearly twice the size of the one we used last year, and it features a large silver space where we can stage bigger performances with dancers and larger groups of musicians."

The Colourscape dome is a multi-chambered labyrinth of pure and intense colour, illuminated by natural daylight and linked by elliptical openings. Visitors wear primary-coloured capes that change hue as they enter the structure and walk around freely, choosing from the myriad routes to experience endless views of radiating colours on a journey where sight and sound meet. Musicians perform anywhere within the labyrinth, with hidden loudspeakers transmitting "spatial music" that echoes along the corridors.

Previous visitors have been so moved by the Colourscape experience, they have reached for the book of tripping poetry: "It's like being wrapped in a rainbow," marvelled one. "I felt I could almost breathe the colours," beamed another on a mellow meander.

Every day there will be events in Colourscape. "These are unscheduled, so anything may happen!" says Simon. "The average visit time for Colourscape will be about half an hour, and during that time you'll hear a good sample of the afternoon's performances."

Colourscape will be open in Museum Gardens, York, from August 3-11, from noon to 5pm each day. Admission is £5 for adults, £2.50 for children, and York Card holders will be admitted at a reduced price. Colourscape is wheelchair accessible.

Updated: 09:49 Friday, August 02, 2002