Picasso began the painting on 11 May 1937, working on a piece of unbleached muslin (349 cm x 776 cm). Since the work was so large, Picasso had to use a ladder and a long-handled brush to reach the furthest corners of the canvas. He spent over two months creating "Guernica". He used only black and white paint to invoke the truth-telling authority of documentary photography. "The protest is found in what has happened to the bodies, the hands, the soles of the feet, the horse's tongue, the mother's breasts, the eyes in the head—the imaginative equivalent of what happened to them in the flesh. We are made to feel their pain with our own eyes."