D.C. microammeter
Date1901-1930
Inventory Number1997-1-1101
ClassificationAmmeter
Subject
Maker
Weston Electrical Instrument Corporation
founded 1888
User
Department of Physics, Harvard University
founded 1884
Cultural Region
Place of Origin
Place of Use
Dimensions20 × 20 × 19.7 cm (7 7/8 × 7 7/8 × 7 3/4 in.)
Material
Accessoriesstandardization certificate on inner surface of lid
DescriptionA wooden box with a hinged lid that allows access to its top half. Inside one finds a metal box with an arc-shaped window, the contours of which are outlined by a black metal frame that also forms a semicircle on the exposed part of the instrument (probably a full circle). The frame seems to be decorative.
The scale of the instrument is linear, in black numbers going from 0 to 500 (microamperes). There is a reflective band below the scale and the pointer consists of a thin needle.
There are two electrical connectors, one at the top left corner of the box, the other at the top right corner. The one on the right is labelled by a metal knob on the edge of the wooden box as "+".
The box has two metal brackets on top that probably once held a leather strap. The white triangle indicates that is was used for instruction in the Physics Department, Harvard University.
The scale of the instrument is linear, in black numbers going from 0 to 500 (microamperes). There is a reflective band below the scale and the pointer consists of a thin needle.
There are two electrical connectors, one at the top left corner of the box, the other at the top right corner. The one on the right is labelled by a metal knob on the edge of the wooden box as "+".
The box has two metal brackets on top that probably once held a leather strap. The white triangle indicates that is was used for instruction in the Physics Department, Harvard University.
Signedbelow scale: WESTON D.C. MICRO-AMMETER
on standardization certificate: WESTON D.C. MICROAMMETER, MODEL 45 (322 striked through)
on plaque: MADE BY THE / WESTON ELECTRICAL INSTRUMENT CO. / NEWARK, N.J., U.S.A. / PATENTED / [9 patent dates] / MODEL 45 No. 29111
Inscribedaround screw: 0 / CORRECTION
in white paint on box: DC AM / 000500
Curatorial RemarksFound by Brian Shaban in the Harvard University Physics department trash. The standardization certificate is from April 23, 1947. The instrument is very likely to be much older, from 1901-1930.
FunctionAn ammeter for measuring very small direct electrical currents. It is most likely a galvanometer type. Seems to be designed for portability.
ProvenanceFrom the Department of Physics, Harvard University.
Weston Electrical Instrument Corporation
Date: circa 1924
Accessories: standardization certificate from Jan 7, 1924 inside lid
Object number: 1997-1-1055
Weston Electrical Instrument Corporation
Date: circa 1921
Accessories: standardization certificate on inner surface of lid
Object number: 1997-1-0332
Weston Electrical Instrument Corporation
Date: circa 1922
Accessories: standardization certificate from 1922 inside lid
Object number: 1997-1-0337
Weston Electrical Instrument Corporation
Date: 1901-1930
Accessories: standardization certificate on inner surface of lid
Object number: 2003-1-0038
Weston Electrical Instrument Corporation
Date: 1900-1930
Accessories: standardization certificate on inner surface of lid
Object number: 1997-1-1183
Weston Electrical Instrument Corporation
Date: 1901-1920
Accessories: undated standardization certificate on inside of lid
Object number: 1997-1-0325
Weston Electrical Instrument Corporation
Date: 1920-1930
Accessories: standardization card from the A.S. Mancib Co.
Object number: WJ0951
Weston Electrical Instrument Corporation
Date: circa 1913
Object number: 1997-1-0328
