In the indoor winter garden of the Institute of Child Health in London a tall mirror-polished stainless steel monolith rises from a reflective pool. The surrounding coping is of polished black granite, and the base of the sculpture is of the same green Kirkstone as the surrounding floor.
Water flows down the surfaces creating rollwave patterns. At the base the reflected image of these descending ripples creates an illusion of other ripples rising from the depths of the pool to meet them at the surface. Variations to these effects are introduced by increasing and diminishing the flow rate by means of a cyclic timer interrupting the operation of the pump.