Manfacturer: Shelby Electric Co.
The mushroom shaped lamp shown here is typical for Shelby Electric Co, which was an old lamp manfacturer based in Ohio. According to advertisements by the company, the reason for this shape is improved light distribution which permits more downlight, since the typical straight sided lamps of the time tended to cast more light on the sides. This lamp has a slightly chipped tip but vaccuum is unaffected and it still lights to this day!
There is a world-wide famous Shelby lamp at the Livermore Fire Station in Livermore, CA which reportedly has been burning continously since the lamp was installed in 1901. Check out the following link to their website!
Lamp: Antique Carbon Filament
Wattage: 16 cp
Voltage: 120 volt
Bulb: M-19
Finish: Clear
Base: E-26s Brass Medium Base
Class: A
Filament: Triple loop w/ no support
Lamp Life: 1000 hours
Manf. Date: 1901-05
Country of
Orgin: USA