Description:
Dark wood case; varnishes; two brass hinges; button-operated spring clasp on side. Silver color circular dial with single needed marked with 0 to 90 scales; face of dial etched "E. A. BARNES." Three brass screw contact and brass carrying handle on top. Opens laterally to reveal blue two velvet-covered cores (wire winding?) with what appears to be an adjustment screw. Penciled inside back "1883."
Evidence suggests this was invented or made by Barnes to go with telephone 38.493 that was made by him. E. A. Barnes was "chief inspector" at the Fort Wayne Electric Works beginning in 1889, See OFN , 67:1 (2004), p. 28. From American Heritage Dictionary--Galvanometer: An instrument used to detect, measure, and determine the direction of small electric currents by means of mechanical effects produced by a coil in a magnetic field. Original card reads "Lineman's detector . . . used by telephone linemen to detect trouble in the in the lines."
Evidence suggests this was invented or made by Barnes to go with telephone 38.493 that was made by him. E. A. Barnes was "chief inspector" at the Fort Wayne Electric Works beginning in 1889, See OFN , 67:1 (2004), p. 28. From American Heritage Dictionary--Galvanometer: An instrument used to detect, measure, and determine the direction of small electric currents by means of mechanical effects produced by a coil in a magnetic field. Original card reads "Lineman's detector . . . used by telephone linemen to detect trouble in the in the lines."
Object Name:
Galvanometer
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