Since David Hockney's recent lament on the supposed desuetude of drawing, the practice is back on the agenda. For Petherbridge, it never went away. "Drawing," she says, "is the passion of my life." She is writing a book on the subject, she has selected exhibitions of modern and historical drawings, and she herself is a virtuoso technician. Recently, she has been drawing the cavernous, Piranesian interior of Bankside power station, before the Tate starts work on the place.
Audiences for the recent "Drawing the Line" travelling show, selected by Michael Craig-Martin, and for Petherbridge's earlier selection of drawings, "The Primacy of Drawing", have been large. People like looking maybe because the means, if not the aspirations of draughtsmen and women, seem graspable, intimate, quotidian. Drawing is essentially a private art, and one to which artists often return at pivotal moments in their careers.
Petherbridge also thinks, like Hockney, that the new technologies have a lot to learn from the low-tech art of drawing, but takes little comfort in the fact that students of Design, rather than of Fine Art, pack her classes. But can our hottest young artists draw, and if they can't, does it matter? Drawing is a core activity, feels Petherbridge: it is visual thinking, idea made concrete with the most primitive tools. A great deal of contemporary painting aspires, she believes, to the condition of drawing - to its spontaneity and immediacy. But without a sense of the history and breadth of the oldest of all artistic practices, 20th-century artists are forever doomed to repeat themselves. "You can't keep rediscovering Malevich and Duchamp," she says. Without drawing, art itself could turn into a kind of Death Room.