Bewley’s Oriental Cafe in Dublin and a completely extraordinary stained-glass window scatters light on our coffee cups. I drink while small butterflies and exotic birds flutter above me.

I have never forgotten this window – unlike any I had ever seen. I later learnt that it was designed by Harry Clarke in 1927-8.

Clarke combined exceptional technique with unparalleled imagination. His illustrative draftsmanship, unique in the world of stained-glass, means that, once you have seen one of his windows, it is impossible not to recognise his hand.

It is also impossible not to recognise his genius. Here, in the following video, in full bloom, is his masterpiece, ‘The Eve of St. Agnes’, inspired by John Keats’s poem.

Like Keats, Clarke died young of TB. But he left us over 130 stained-glass windows and with them, the world a brighter place.