Pisa's platform unearthed

Cornelia Parker was nominated for the Turner Prize in 1997, but would have fitted snugly into this year's line-up, given the similarity of the feel and style of her work to that of Fiona Banner and Keith Tyson. Together they sit at the soft end of the spectrum of contemporary conceptual art, creating work that is often a visual manifestation or illustration of a "quirky" idea.

For Parker, that often involves committing acts of violence or working odd transmutations on objects culled from the everyday world. In the past she has blown up a garden shed and artfully arranged the resulting fragments to create Cold Dark Matter, now on display in Tate Modern, and flattened a number of brass musical instruments to form Breathless, a commission by the V&A for its new galleries.

Here, Parker exhibits work created over the past two years that is very much in keeping with her familiar style. Indeed, the most visually impressive work on display, the Subconscious of a Monument, is the repetition of a piece Parker made in 1999, albeit with different elements. Filling the front gallery, it consists of a myriad of evenly spaced thin wires that run from ceiling to floor, from which lumps of light brown, desiccated soil hang at irregular intervals. The room looks as if it is filled with particles of soil floating in a gravity-free atmosphere.

The soil, and this is the "conceptual" bit, was excavated from beneath the leaning tower of Pisa when measures were taken to prevent its imminent collapse. The irony, that this particular soil has failed to perform one of the basic functions of soil by providing the foundation for buildings, is in truth a rather poor one and pointless to highlight, for the piece's power derives solely from visual impact.

Downstairs, things do not improve, filled as it is with works whose existence is justified only by their rather dull quirkiness. The Tooth Drawings are just that: a series of individually framed little bundles of thin gold wire made from reclaimed dental gold. Blue Shift, meanwhile, consists of a lightbox recessed seamlessly into a wall in a darkened lower gallery, in which is displayed the blue shift worn by Mia Farrow in Roman Polanski's Satanic classic Rosemary's Baby.

As with much work in this style, Parker has sacrificed most of the qualities that art can have in the pursuit of ideas and concepts that are interesting for only the briefest of moments.