milliammeter
Datecirca 1915
Inventory Number0468
ClassificationAmmeter
Subject
Maker
Campbell Electric Corporation
founded 1916
User
Department of Physics, Harvard University
founded 1884
Cultural Region
Place of Origin
Place of Use
Dimensions33 × 25.3 × 8.1 cm (13 × 9 15/16 × 3 3/16 in.)
Material
DescriptionCircular, moving coil, double scale ammeter in a metal frame with a white face and black lettering. The face is frosted glass, with a fan-shaped clear glass window for the scale, and a circular clear glass window that shows some of the internal mechanisms at the bottom. There are two small protruding terminals, one at the top and one to the side of the scale. The top scale runs from 0-15, and the bottom scale runs from 0-150.
The internal movement is controlled by an extreme switch, which is pull cord operated. The cord and switch are located at the bottom of the instrument.
The internal movement is controlled by an extreme switch, which is pull cord operated. The cord and switch are located at the bottom of the instrument.
Signedon face: STANDARD / MILLI-AMMETER / CAMPBELL ELECTRIC CO. / LYNN, MASS., / 108112
FunctionFrom original card: "This instrument was probably used by Professor Duane in his experiments with x-rays. It may have been part of the large high voltage source box x-ray tubes."
Weston Electrical Instrument Corporation
Date: circa 1911
Object number: 0525
Weston Electrical Instrument Corporation
Date: 1890-1900
Object number: 0418
Weston Electrical Instrument Corporation
Date: circa 1931
Object number: 0528
Weston Electrical Instrument Corporation
Date: 1890-1900
Accessories: shunt apparatus (0417b)
Object number: 0417a
