Underneath the glass block floors of the passenger shelters cantilevered out over the viaduct a double line of cold cathode tubing has been installed in the form of an oval.
The ovals encompass each of the glass floors, touching the centre of each side. They are constantly illuminated and, visible through the glass floor from above, they describe an oval line of white light.
From the station approaches below they exert a different presence as the light escapes through its protective housing.
Ron Haselden was intrigued by the way in which the platforms and shelters project beyond the original stone structure of the viaduct, perfectly balanced over the fulcrum of the elevated railway line. Accordingly the light levels of the ovals are programmed to rise and fall in response to local changes in wind direction. As the light level of one oval rises in intensity so the light level of its partner decreases at the same rate.
In contrast to the station, which is held in constant balance across the viaduct, the balance of the ovals is forever in a gentle state of change.