Metallic thermometer having 7½” aluminium printed dial with temperature range displayed in degrees Fahrenheit,  with a range from -20 to 140 degrees Fahrenheit, marked at the centre with the “Rototherm Thermometer” logo, with upper case “F” (Fahrenheit), the lower part marked “BRIT.PAT. No. 378314 & World Patents,” and “British Made.” Blued steel pointer. Glazed.

Conventional bi-metallic movement of the Rototherm pattern, all contained within a pressed metal flared case, silver grey enamel finish.

Condition: The dial with minor darkening at centre, otherwise appearing clean. The metal case might have been re-painted. Serviced, good working order and generally good condition.

Comments: Large metallic wall barometers are for some reason scarce. This one has good aesthetic qualities as well as utility.

Rototherm invented the bimetallic thermometer and patented it in 1932. By 1934, the company was known as “The British Rototherm Co Ltd” which enables us to date this instrument accurately.