Westinghouse tantalum filament "mill" lamp
date: label: date made
content: ca 1908
name: label: maker
content: Westinghouse Electric Corporation
notes: label: Description (Brief)
content: Westinghouse tantalum filament "mill" lamp, circa 1908. Brass medium-screw base with skirt, two glass insulators. Two drawn tantalum filaments (in series) with 12 upper, 22 center, and 10 lower copper support hooks. Crimp connectors, Siemens seal, cotton insulator. Tipped straight-sided envelope. Westinghouse label on lamp reads: “Westinghouse Tantalum [inked 223] V 50 W, patent label in stem: “The manufacturer of this lamp is licensed under patent noted on other side.” “Mar-20-94 516,800 APR-16-95 537,493 APR-28-03 726,293 AND OTHERS H.P.5036”. Stamped on base-skirt: “-PATENTED Nov. 08 19[04] Nov. 22 19[04]”. “T” inked on stem, “X22 50” on one side of press, “7578” on other side, “224- [?]V” in base. Label on top is inked: “47D4-4”.
label: Description (Brief)
content: The element tantalum was used as a lamp filament during the first decade of the twentieth century. Although somewhat more energy efficient than carbon filaments common at that time, tantalum filaments did not work well with alternating current. They were phased out in the early 1910s when manufacturers introduced lamps made with tungsten filaments.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2014.0058.06
label: accession number
content: 2014.0058
label: catalog number
content: 2014.0058.06
objectType: label: Object Name
content: Light Bulb
label: Object Name
content: incandescent lamp
label: Other Terms
content: Light Bulb; Lighting Devices; Edison; Cage; Metal
physicalDescription: label: Physical Description
content: glass (overall material)
label: Physical Description
content: metal (overall material)
label: Measurements
content: overall: 7 in x 3 in; 17.78 cm x 7.62 cm