GLOSSARY +++ VISUAL MUSIC HISTORY**

Lumia

Thomas Wilfred's name for the art of light itself: slow, silent compositions of drifting luminous form, performed on his Clavilux instruments.

Wilfred insisted light deserved an art of its own, not accompaniment. Lumia was his name for it: compositions of morphing, aurora-like forms, typically silent, sometimes hours or years long, played on instruments he called Clavilux.

He performed lumia recitals across the 1920s in concert halls, later building self-playing cabinets whose mechanical scores cycle without repetition. MoMA’s long-running display of Lumia Suite, Op. 158 introduced generations to the work, and a 2017 retrospective revived his standing.

Lumia’s break with music made a lasting point: light composition has its own tempo, far slower than sound. Ambient visuals, from screensavers to gallery installations, live downstream of that discovery.