Atlas 60W blue bulb, boxed. Made at Atlas Lamp works, London

Part of the Bob Gray collection of electrical objects.

Coloured bulbs became popular in the 1920s and were created by putting fluorescent materials into the glass. This type of bulb was generally used in shops and houses. It was made at the Atlas Lamp Works, part of Thorn Lighting, in Edmonton, north London. Atlas produced this type of 60 watt, gas-filled lamp in a variety of colours including red, orange, green, 'flame tint', yellow, ivory, and pink. During the war, Atlas also produced blue lamps for use in blackout conditions. Blue light penetrates less far into the atmosphere than red and yellow light and these bulbs were therefore safer under conditions where street lights were banned and inside lighting was not allowed to be visible from the outside.