The Earth at night as seen from space -- Lascaux : the first lamp -- Time of dark streets -- Lanterns at sea -- Gaslight -- Towards a more perfect flame -- Life electric -- Incandescence -- Overwhelming brilliance : the White City -- Niagara : long distance light -- New century, last flame -- Gleaming things -- Alone in the dark -- Rural electrification -- Cold light -- Wartime : the return of old night -- Lascaux discovered -- Blackout, 1965 -- Imagining the next grid -- At the mercy of light -- More is less -- The once and future light -- Lascaux revisited.