This is a
squirted cellulose filament lamp manufactured
about 1900 with a porcelain base. For many years, from their year of introduction in 1894 to 1900, squirted cellulose filament lamps were manufactured with plaster of paris bases [see A21]
. Only for a brief period in 1900 were they manufactured with porcelain bases. After 1900 onward to 1918, when production of squirted cellulose filament lamps ceased, they were manufactured with glass bases. The higher wattage squirted cellulose lamps were fitted with skirted bases [see A23]
to allow the wide and large filaments to fit into the bulb and also dissipate the extra heat generated by the longer filaments. Squirted cellulose filaments were manufactured by dissolving cotton in a solution to form a syrupy mixture that was then forced or “squirted” through an orifice or die straight into another solution of alcohol, which served to harden the squirted filament. The resulting strengthened filament could then be wound on drums and cut to any desired lengths and then carbonized. (The length of split bamboo filaments, on the other hand, could be no longer than the distance between the joints of the bamboo cane.) With their lower specific resistance, these filaments had to be very long in order to give off much light. The final configuration may be one single very long hairpin filament, two hairpin filaments connected in series, or one filament having a loop, which was either anchored to the stem or spiraled. All of these filament configurations could be mounted inside either a pear shaped bulb or a straight-sided bulb.
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