Ti Parks’s vibrant painting exemplifies the aims of hard-edge painters working in Australia in the late 1960s, being characterised by repetition and variation in equal measure. Like many of his contemporaries, Parks found stimulus within domestic and urban spheres: taking the simplified colours and patterns of linoleum floorcoverings as a starting point, the artist introduced subtle shifts to interrupt their underlying rhythms and arrest the viewer’s eyes.

In Number one, a grid of green squares appears to vibrate out of position – an effect aided by dynamic contrasts of warm and cool colours, and by Parks’s equivocal treatment of light and shade. Adding ‘shadows’ that become more pronounced in the lower registers of the painting, Parks has given the squares a sense of three-dimensionality; while areas of magenta and cyan in the bottom right of the painting suggest a diagonal beam of light cast across a flat surface, creating a visual tension between flatness and depth, ‘figure’ and ground.