Accession No

4137

Brief Description

Wheatstone Bridge, Callendar and Griffiths pattern II, by Cambridge Scientific Instrument Company Ltd., English, c. 1900

Origin

England; Cambridge

Maker

Cambridge Scientific Instrument Company Ltd.

Class

electrical

Earliest Date

1900

Latest Date

1900

Inscription Date

Material

Wood; Metal (brass); Ceramic (porcelain); Plastic (ebonite)

Dimensions

length 450mm; breadth 281mm; height 250mm

Special Collection

Cambridge Instrument Company Collection

Provenance

Donated by the Cambridge Instrument Company in 1974.

Inscription

“No. 1162 / SCIENTIFIC INSTRUMENT CO. LTD. CAMBRIDGE. / CALLENDAR & GRIFFITHS PATENT SELF-TESTING BRIDGE” (on top)

Description Notes

Wheatstone Bridge, Callendar and Griffiths pattern II; made by Camb. Sci. Inst. Co., c.1900;
Ten resistance coils connected to brass and porcelain sockets; seven brass and ebonite plugs; coils labelled from ‘5’ to ‘2560’ (0.05 to 25.6 ohms; each coil differs by 0.05 ohms from the sum of those below it); four pairs of brass terminals, marked ‘G’, ‘P’, ‘C’, and ‘B’ respectively; three position brass seitch; double slide wire with 30 cm, brass scale; vernier scale on sliding contact; wooden case with ebonite top.

References

Events