"A shop assistant shows a customer a luminous flower in Selfridge's department store, London. These flowers were one of numerous blackout accessories available in 1940 to make pedestrians more visible on the dark streets of the capital." A shop assistant shows a customer a luminous flower in Selfridge's department store, London. These flowers were one of numerous blackout accessories available in 1940 to make pedestrians more visible on the dark streets of the capital.