I spent two cold weeks last winter in a narrow sandstone shelter above a wind-cut valley, tracing only what could still be seen without touching the wall. The animal that held the room was not complete: the head had thinned into smoke, the legs had gone to dust, and the flank remained as a slow red-brown tide.
A careful record does not brighten the ground. It lets the wall stay dark enough to tell the truth.
Do not repair the missing line
A good drawing begins by refusing the clean panel. We mapped the surface at dawn, when the stone kept its grey warmth and the old clay-white marks appeared only as brief interruptions. The point was not to rescue a perfect creature, but to notice how pigment, weather, smoke, and time still share one surface.