General Electric tantalum filament lamp
date: label: date made
content: ca 1908
notes: label: Description (Brief)
content: General Electric tantalum filament lamp, circa 1908. Brass medium-screw base with skirt, two glass insulators. Tantalum filament with 11 upper and 10 lower supports, offset leads, Siemens Seal, crimp connectors, cotton insulator. Tipped, straight-sided envelope with taper at neck. “h11” inked on one side of press, “f50” on the other side. “11[___]” inked in base. “- Pat. Nov.8.1904 Nov.22.1904 -” stamped on base. Patent label in stem has a red GE logo watermarked and reads: “Manufactured under patents noted on other side.” Other side hidden. Catalog number on envelope.
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
creditLine: label: Credit Line
content: from General Electric Company, Edison Lamp Works
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.307432
label: accession number
content: 68276
label: catalog number
content: 307432
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: tantalum (overall material)
label: Physical Description
content: glass (overall material)
label: Measurements
content: overall: 5 1/4 in x 2 1/2 in; 13.335 cm x 6.35 cm