Accession Code: wu0175 Title: Nineteen Greys Date completed: 1968 Medium: Prints Material: Screenprint Height (mm): 755 Width (mm): 759 Depth (mm): n/a Inscription: None Location Name: Senate House Location Description: Wellbeing Support Services Location Floor: 1

Bridget Riley first started to work with 'Optical Art' in the 1960's. Originally she worked in black and white creating graphic work which produced optical illusions. Gradually she introduced colour into her work and began to exploit the energetic nature of opposite colours. She uses extreme precision to create these optical effects. Sometimes she even calculates the correct viewing distance which produces the best effect for the viewer. It is easy to overlook the subtle effect created in this work. The oval silver ellipses on the opaque grey-blue background seem simply to be repetitive until you begin to see that they are not all identical but gradually tilting, turning and changing shade.