Jason Clarke Antiques has dated this piece to the 1920s.
The thermometer is fastened to the scale by means of two brass loops with screws that are secured by four nuts to the back of the plate.

An interesting example for its decorative ceramic scale plate whilst remaining a very useful tool for monitoring cellar temperatures when storing wine.
I have little doubt that this example was manufactured by the hugely famous instrument making firm of Negretti & Zambra but I have refrained from exact attribution given the lack of any specific maker’s mark on the scale. I have encountered and previously sold similar examples by Peter Stevenson of Edinburgh but the style and design is somewhat different.
Circa 1920
Jason Clarke Antiques has dated this piece to the 1920s.
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