1893

In 1893, squirted cellulose filaments were introduced and were used in large quantities for many years after by General Electric, the company Edison is credited with helping to create.  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.)  But since the squirted cellulose filament had a lower specific resistance, it had to be very long in order to give off much light.  Thus squirted cellulose filaments tend to be long with a circular cross section (but not threadlike) and black in color.  They were usually mounted in either a long hairpin fashion, two filaments in series, or as a single oval anchored loop of one filament.  The higher wattage squirted cellulose lamps, which generated more heat, were fitted with skirted bases [see A23] to allow these filaments to fit into the bulb.  (The skirted bases also helped dissipated the extra heat generated by these filaments.)  The use of squirted cellulose filaments was largely discontinued in 1918.

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