Accession No

4589

Brief Description

Ohmmeter by the American Electric Specialty Company, 1900

Origin

New York; USA

Maker

The American Electric Speciality Co New York USA

Class

electrical

Earliest Date

1900

Latest Date

1900

Inscription Date

1900

Material

wood; metal (brass, two white metals, copper); paper; plastic (ebonite, artificial leather); wax

Dimensions

height 130mm; breadth 125mm; length 430mm

Special Collection

Provenance

Transferred from the Department of Physiology, University of Cambridge, on 23/01/1997.

Inscription

‘A DIRECT READING OHMMETER
MANUFACTURED BY
THE AMERICAN ELECTRIC SPECIALTY CO,,
123 LIBERTY STREET, NEW YORK CITY.’ (paper label inside lid)

Description Notes

Wooden case with bottom missing; wood and metal handle, one of two brass hook fasteners (one missing), latch on the lid. Inside: paper scale running along both sides of an ebonite central division. Scale divided 0 - 2,000,000, numbered 0, 1000, 2000...10000, 12000...20000, 25000, 30000, 35000, 40000, 50000...100000, 150000, 200000, 250000, 300000, 400000, 500000, 1000000, 2000000; also marked for 0 - 10, 0 - 100 and 0 - 1000 (where final number is set at 100000 on the main scale). Selection of scale is by colour coded plug and key. White metal wire stretched down centre of scale. Three brass terminals at right-hand end. Inside lid is a paper label giving instructions and accuracy. Also artificial leather slip case for stylus, now missing. In base is a space for a telephone earpiece, now missing, accessed by a sliding door in the side. Also visible are four wax-coated spools and wires with cloth insulation; one of the connecting wires is detached at one end.

Condition fair (some corrosion to latch and handle); incomplete (base, stylus, hook fastener and telephone earpiece missing).

References

Events