The flexibility of charcoal is key to Kentridge's work across many disciplines. 'You can change it as quickly as you can think,' he observes. 'It became a way of thinking rather than a physical medium for me.' ['Transformation', interview with the San Francisco Museum of Modern Art, January, 2006, available online.] Yet this change does not obliterate previous versions - any erasure is always 'imperfect', leaving a trace of its history. Kentridge often builds up stop-motion animations from such drawings, but this example is a stand-alone work. It is part of the 'Arc/Procession' series, each of which examines a tranche of a crowd. This composition implies continuation beyond the limits of the drawing - a slice of 'thick time', encompassing the near past, present and future. The curve also frustrates an attempt to view the entire composition at once, reproducing the fragmented experience of looking at or being part of a large crowd.