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Description: | SIEMENS 6V 108W 23 (black stencil on the end cap). MANU Siemens Electric Lamps and Supplies Ltd circa 1955 England DES after SWAN,Joseph,Wilson,Sir. 1878 Newcastle-Upon-Tyne England This is a 6 Volt 18 Amper 108 Watt class F projector lamp with a standard Edison screw end cap type E27/25 and a clear tube shaped envelope which allows tungsten to condense at the top of the tube without affecting the optical properties of the tube in the area of the filament. It was intended to be mounted vertically and burned cap down. The single ductile tungsten ribbon filament is welded to the nickel-nickel/iron-copper composite lead in wires.The first tungsten filaments were developed circa 1906 using a process similar to the squirted carbon filament but a ductile tungsten process, by which tungsten powder is compressed and then forged into billet before being drawn through a series of diamond dies, was developed in 1909. The envelope is a machine made type without a pintel or pip. The lamp was filled with a nitrogen or nitrogen/argon mix through a hole in the base of the cane This tube was a spare designed for use in a 9mm home cine projector but was intended for use in a microscope illuminator or as a projector lamp (see carton). It would have probably been operated in conjunction with a mirror. The carton associated with this lamp, which is for a Watson "Pointolite" lamp, is in a cardboard box on top of SCI:1. | License: | http://www.hmag.gla.ac.uk/spirit/rights/ | Publisher: | Hunterian Museum and Art Gallery, University of Glasgow | Rights holder: | Hunterian Museum and Art Gallery, University of Glasgow | Subjects: | SCIENTIFIC COLLECTION : | Source: | Hunterian Museum | Creator: | Hunterian Museum and Art Gallery, University of Glasgow | Identifier: | http://www.huntsearch.gla.ac.uk/cgi-bin/... | Language: | en-GB | Go to resource |
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