Artifact #22

Historic Edison Collection

Most Famous Lamps in the World

Famous Edison Light Bulbs DISCOVERED After Century in Darkness

Artifact 22 - This 1894 Edison Lamp has two (2) treated bamboo carbon filaments connected in series. This is the only lamp of its kind known to exist. In 1905, the General Electric Company finally perfected this "Double Hairpin" lamp filament design by forming these carbon filaments in the new (at the time) electric resistance furnace, capable of 3,500 deg. C (6,300 deg. F). The series design was the first to be called the "Edison GEM" lamp. The acronym stands for General Electric Metallized because the graphite coating on the carbon filament took on metal like properties after being subjected to the electric furnace heat treating process. The metallized filament became the hallmark design of the famous highly efficient Edison GEM lamp. This filament design proved to be short-lived, in 1907, the early Edison tungsten lamp began to take some market share from the twin series Gem carbon filament lamp. In 1909 the two piece twin hairpin GEM filament lamp became obsolete, replaced by the "one piece" GEM filament. By 1911, the new drawn tungsten filament brought an end to the carbon GEM era. Lamp 22 provides a rare glimpse at a prototype design that was a decade ahead of its time.

2006 is this lamp's 112 th. Anniversary

Go To the Collection Group Exhibit

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