galvanometer
Datecirca 1850
Inventory Number0115
ClassificationGalvanometer
Subject
Maker
Daniel Davis, Jr.
1813 - 1887
Cultural Region
Place of Origin
Dimensions23.7 × 22.4 × 11.3 cm (9 5/16 × 8 13/16 × 4 7/16 in.)
Material
Bibliography
DescriptionTwo pairs of galvanometer needles (missing) were originally suspended from the brass vertical posts, on the two arms, so that one needle of each pair was within (or over) a coil of either six or twelve turns. (The needle could also be pivoted from inside the coils, without having to be suspended.) The coils are also paired, painted green, and mounted on a mahogany base supported by four brass ball feet.
Connections with a battery for each coil are made at the binding posts on each side of the base. This instrument allows comparison of the effect of the magnetic needle, placed within a coil of six turns, and within a coil of twelve turns. Both circuits could even be operated at the same time.
This instrument has an old Harvard number stamped: "8-51".
Connections with a battery for each coil are made at the binding posts on each side of the base. This instrument allows comparison of the effect of the magnetic needle, placed within a coil of six turns, and within a coil of twelve turns. Both circuits could even be operated at the same time.
This instrument has an old Harvard number stamped: "8-51".
Signedunsigned
Curatorial RemarksThis instrument is not described in any edition of Davis's books on magnetism.
FunctionTo demonstrate how, by adding turns to a galvanometer coil, the angle of deflection of a magnetic needle is increased.
ProvenanceFrom the Department of Physics, Harvard University.
Daniel Davis, Jr. & E. B. Horn
Date: circa 1850
Object number: 0106
Daniel Davis, Jr.
Date: circa 1848
Accessories: battery (0566b); pair of shock handles (0566c,d)
Object number: 0566a
Daniel Davis, Jr.
Date: 1848-1855
Object number: 0120
Daniel Davis, Jr.
Date: circa 1848
Object number: 1997-1-1801
