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Bristol Cardboard Filament Lamp with Neck Plugged into Wooden Standing Lamp Base

This is actually Thomas Edison’s first commercial light bulb sold to the public.  It was designed for mounting into a wooden standing lamp base as shown, which may or may not have come with your bulb.  Notice the fragment of the broken Bristol cardboard filaments in the necks of both lamps.  It was manufactured in Menlo Park, New Jersey from November 1879 to May 1880.  Edison employed filaments made of horseshoe-shaped carbonized cardboard connected by means of both carbon paste and copper clamps with screws.  (This method proved to be very cumbersome and unreliable and often resulted in broken filaments, cracked bases, and electric arcing.) Nevertheless, these were the first commercially available lamps ever sold.  Each lamp would last for about 150 hours, a definite improvement over Edison’s first successful lamp two months earlier, which lasted at most for 40 hours.  Hundreds of them were produced and sold for household, industrial, and street lighting.  They were also publicly exhibited at Menlo Park on New Year’s Eve of 1879/1880, attracting large swarms of crowds.  As news of Edison’s successful commercial lamp spread, the price in gas stocks plunged while those of the nearly two-year old Edison Electric Light Company increased to $3,500 per share!  The future of electric lighting looked very “bright” indeed, no pun intended. See Figure 153? for a print showing how this Bristol filament bulb was connected to the electric circuitry.

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