| A late 18th Century pocket thermometer in a steel case glazed on both sides. Large circular bimetallic strip acting on the counterbalanced end of the light brass rack. Central brass pinion with hairspring to hold the rack in contact with the bimetallic strip. Blue steel hand indicating the
temperature on Centigrade, Fahrenheit and Reaumur scales marked on the double sided silvered dial. Steel case glazed on both sides, a slide in the band moves the bimetallic strip, perhaps to adjust the indication to a known standard.
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