This time as I lay awake in bed, I invented double skin stained glass. There’s a fair gap between the two skins, maybe enough for people to walk between, and the thing resolves into different small images or words, depending on the time of day and year. The sunny side is smooth and the inside side is frosted. It could be modelled on a computer. As it turns out, I didn’t invent it — Janet tells me there’s been something similar at the National Memorial Arboretum.
See the effect of light coming through coloured glass here.
the adventures of retirement