identify your lightbulb > bulb identification key

This is a later model of General Electric’s Photoflash lamp, model Number 22.  It differs from Model Numbers 20 and 21 in that the bulb is filled with a mass of aluminum wire rather than sheets of crumbled foil.  Still, it was designed for a one-time use only.  It was probably introduced in 1942.  Other wire-filled photoflash bulbs were manufactured by General Electric – the No. 7 (also known as the Syncho Press No. 7) and the No. 16 were introduced in 1939.  The No. 11 [see A113], which originally was manufactured with aluminum foil, came out later.  These seem to be smaller versions of the No. 22.  The No. 7 and the No. 16 were sold for 18 and 20 cents respectively.  Still other aluminum-wire versions were introduced later in that same year to help photographers meet all the “basic requirements of flash photography” such as the No. 30 Photoflash lamp and the No. 31 Photoflash lamp.  No. 30 emitted a flash rate of 40,000 to 45,000 lumen-seconds while the No. 31 emitted 70,000 to 80,000 lumen-seconds and was recommended for all “focal-plane” cameras.  They sold for 28 and 30 cents respectively in 1939, a bit more expensive than the No. 7 and No. 16 models.  A No. 50 Photoflash later came out, similar to the No. 31 in size but emitting 93,000 lumen-seconds.  For more information on photoflash bulbs, click here [see A55].  For further dating, if the bulb should have MAZDA, GE monogram, wattage and/or voltage etched on top of bulb [see A44], the bulb was manufactured from model’s year of introduction to 1945, when the MAZDA trademark was discontinued, or the year the model was discontinued.  If the bulb has the GE monogram etched on top of bulb but WITHOUT the MAZDA trademark, which was discontinued in 1945, bulb was manufactured from 1945 until the model was discontinued.

  thomas edison > website navigation thomas edison > home page thomas edison > timeline : early life thomas edison > timeline : inventing the incandescent lamp thomas edison > timeline : after lighting thomas edison > timeline : legacy of invention thomas edison > classroom thomas edison > interactive modules