From the 1980s, Sean Scully began to incorporate relief elements into his paintings to give them an emphatic physical presence. Working on a monumental scale in paintings such as Once, he expanded their expressive range with broad areas of viscous, pulsating colour to evoke a sense of the metaphorical and the sublime, in which black operates to convey feelings ranging from the solemn to the sinister. Once seems to offer an architecture of dignity and healing. It anticipates later works that respond to the physical world of sky, sea and ancient stone as tonal registers of human emotions.