Thomas Edison and his assistant Francis Jehl reenacting the first successful electrical incandescent lamp for the fiftieth anniversary celebration in 1929.

Notice that the “first” electric lamp is not in any true socket but is mounted upside down to a large apparatus that included a tall mercury vapor pump which drew air out from the bottom of the bulb (which is actually the tip) to create a nearly perfect vacuum necessary for the filament to glow brightly without rapidly burning up.  (Any oxygen in the bulb would allow the filament to quickly flame up and then burn out in a matter of seconds, much like a matchstick.)  From the top (which is actually the neck) the terminal wires were connected to an electric power source.


 
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