Rototherm Vintage Thermometer:
A simple industrial fahrenheit bimetallic Rototherm vintage thermometer, which has a chrome and glass bezel front. The back of the thermometer is black enamelled steel.
The thermometer is in fair vintage condition with some pitting to the metal and the face has slightly yellowed with age. The Rototherm does appear to be working but has not been calibrated for accuracy.
It’s approximate diameter is 6.5cm (2.5″).
It was made by The British Rototherm Co. Ltd. London, British Patent Number 378314. A search of the patent database shows that the patent dates to the 1930s.
This simple industrial thermometer is a ‘must have’ item for the ‘man cave’, ‘she den’, study or office.
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Some Trivia For You!
Rototherm invented the bimetallic thermometer in 1934. The thermometer has a metal pointer that moves up and down a circular scale. The pointer is mounted on a coiled piece of metal called a bimetallic strip. The hotter the temperature, the more the bimetallic strip expands, and the more it pushes the pointer up the scale.