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This bulb has a carbonized split Japanese bamboo filament and copper plated joints connecting the filament to the platinum inner leads. The base is similar to that of the previous lamp in production [see A14] except that the cone-shaped copper ring is now eliminated as the second electrical contact terminal.  It has been substituted with a straight-sided copper contact at the bottom of the base.  The entire copper arrangement is constructed over plaster of paris.  This bulb was manufactured about mid-1882.  It is interesting to note that the base of this bulb will even fit into today’s sockets.

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