18 Feb-30 April 2005. A site-specific project comprising LeWitts New pencil walldrawings: five geometrical cube-like forms drawn in pencil directly on the walls of the gallery.

When I received an invitation to Le Witts latest exhibition I wondered how he could possibly add anything fresh to his decades-old accomplished and settled manner of temporarily decorating walls. But he has done just that in his New Pencil Walldrawings, an entirely new invention.

When you enter the gallery with its walls painted a dazzling white under renaissance vaults, you are caught in the mesh of a myriad of fine lines that sets everything aglitter.

Five great wall drawings have been executed by three Italian assistants according to the instructions of the conceptual American who lives in Spoleto. The work is the manifestation of an idea, it is an idea and not an object, Le Witt explains. His exquisite patterns are derived from reinterpretations of mathematical calculations of points, lines and planes.

But these extremely subtle, silently rigid grids like the webs of a geometry-minded spider are immensely pleasing to the eye. The marks are wrought with care and meaning but the finery of their visual impact alone stirs us.

They only exist as temporary projects. When the show is over, the sparkle of these hardly-visible yet incisive webs will be painted out. However the conceptualists own little initial layouts for various projects remain and they can be developed permanently on the walls of future owners. Edith Schloss