Accession No
4345
Brief Description
Whipple Temperature Indicator (self-contained Wheatstone Bridge, with direct-reading temperature scale), by Cambridge Scientific Instrument Company Ltd., English, 1902
Origin
England; Cambridge
Maker
Cambridge Scientific Instrument Company Ltd.
Class
electrical
Earliest Date
1902
Latest Date
1920
Inscription Date
Material
wood; plastic (ebonite, ivorine); metal (brass); cloth (canvas?)
Dimensions
length 440mm; breadth 205mm; height 260mm
Special Collection
Cambridge Instrument Company Collection
Provenance
Donated by the Cambridge Instrument Company.
Inscription
“WHIPPLE’S PATENT TEMPERATURE INDICATOR / CAMBRIDGE SCIENTIFIC INSTRUMENT CO. LTD. / No. 1646” (on ivorine plate inside lid)
Description Notes
Self-contained Wheatstone Bridge, with direct-reading temperature scale, Whipple Indicator type; made by Cambridge Scientific Instrument Company, 1902;
Rectangular wooden box with hinged, locking lid and carrying strap; three brass levelling feet; ebonite top on instrument section, which adjoins compartment for batteries; two pairs brass terminals, marked ‘C; and ‘P’, for current and potential leads from resistance thermometer; one pair for connection to batteries; slide-wire, exchangable resistance coil, tapping key, and circular spirit level also mounted on top; spare glazed window showing suspended coil and galvanometer pointer; galvanometer clamp operates when lid is shut; rectangular glazed window showing 14-turn drum dial, with temperature scale from 1 to 1 200 (Celsius); dial is adjusted using circular handle which may be connected to shaft extending through right side of box. With Camb Sc, Inst, Co. repair label, dated 1936, made out to ‘Prof. C.E. (?), Eng. Labs’;
Condition: good (galvanometer suspension intact); complete
References
Events
Description
This is one of the earliest models of the Whipple Temperature Indicator, patented in 1902, and marketed by the Cambridge Scientific Instrument Company (CSIC) for at least 50 years. The manually balanced Wheatstone Bridge circuit allows temperatures to be read directly and easily over a wide temperature range, with precision because of the length of the slide-wire. The instrument was designed by Robert Stewart Whipple, the founder of the Whipple Museum.
Robert S. Whipple (1871-1953), whose father George was the Superintendent of Kew Observatory, joined the CSIC in 1898 as personal assistant to the Company’s co-founder, Horace Darwin. Whipple had previously worked as an assistant at Kew, and assistant manager for L. P. Casella. He became Managing Director of the CSIC in 1905, and served as Chairman from 1935 until 1950, remaining a Director until his death. In 1944, Whipple donated his private collection of historic scientific instruments to the University of Cambridge, founding the Whipple Museum.
FM:41125
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