Thomson-type reflecting galvanometer
Date1880-1910
Inventory Number0246
ClassificationGalvanometer
Subject
Maker
E. Ducretet & Cie
1864 - 1931
Inventor
Sir William Thomson
1824 - 1907
Cultural Region
Place of Origin
Dimensions47.4 × 19.6 × 18.5 cm (18 11/16 × 7 11/16 × 7 5/16 in.)
Material
Bibliography
DescriptionThe galvanometer is supported by a brass column and black tripod, each leg terminated with a leveling screw. Inside the cylindrical brass case there is a moving magnet with a mirror hung in the center of a coil. A damping vane lies below the coil. Glass is found on both sides of the case, with the auxiliary coil mounted on back glass plate. The suspension also supports adjustable bar magnet for zero adjustment.
A paper sticker on the front glass reads: Bobine 37 R = 0w, 520 / Bobine 38 R = 0w, 492 / Resistance Totale 1w, 012
A paper sticker on the front glass reads: Bobine 37 R = 0w, 520 / Bobine 38 R = 0w, 492 / Resistance Totale 1w, 012
Signedon case: E. Ducretet & Cie / à Paris
Inscribedon top of case: N° 274
Curatorial RemarksThere is a blue triangle on this instrument, which indicates it was use in the Physics 3 course at Harvard in the late 1920's.
FunctionElectrical apparatus for detecting and determining the intensity and direction of an electrical current. For a short explanation of how this instrument functioned and was used in submarine telegraphy, see the following website. (At the bottom of that page, the engraving shows a mirror galvanometer very similar to the ones Ducretet produced at that time.)
ProvenanceFrom the Physics Department, Harvard University.
Leeds & Northrup Company
Date: circa 1940
Object number: 0552
Leeds & Northrup Company
Date: circa 1927
Accessories: none
Object number: 0538
Leeds & Northrup Company
Date: circa 1950
Object number: 1997-1-1095
Electric Manufacturing Company
Date: circa 1883
Object number: 0245
Department of Physics, Harvard University
Date: 1900-1920
Object number: 0144a,b
