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Description: | POPE BRITISH MADE 250-16 80 (acid etched on the glass envelope). V10 (written in black on the base of the glass envelope). MANU Pope circa 1925 United Kingdom DES after SWAN,Joseph,Wilson,Sir. 1878 Newcastle-Upon-Tyne England DES after EDISON,Thomas,Alva. 1879 Menlo Park, New Jersey United States of America This is a 250 volt 16 candle power general lighting service lamp with a Swan double contact bayonet two pin cap type No B22/25x26 and a clear bell shaped envelope. The single filament, in the form of four loops, is attached to the copper sheathed nickel iron lead in wires by the carbon tube method and supported by two molybdenum wires from a central stem. The envelope is a machine made vacuum type. Note the "metallised" carbon filament was first produced in 1904-5 and was a double heat treatment of a sqirted carbon filament giving it a glassy or metallic finish. | 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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