Daniel Gabriel Fahrenheit Daniel Gabriel Fahrenheit Daniel Gabriel Fahrenheit FRS (; ; 24 May 1686 – 16 September 1736) was a Dutch-German-Polish physicist, inventor, and scientific instrument maker. Fahrenheit was born in Danzig/Gdańsk, a predominantly German-speaking Hanseatic city in the Pomeranian Voivodeship of the Polish–Lithuanian Commonwealth, but lived most of his life in the Dutch Republic (1701–1736) and was one of the notable figures in the Golden Age of Dutch science and technology. A pioneer of exact thermometry, he helped lay the foundations for the era of precision thermometry by inventing the mercury-in-glass thermometer (first practical, accurate thermometer) and Fahrenheit scale (first standardized
Six's thermometer and minimum scales; this shows the current temperature and should be the same on both scales. If the two readings are not the same, then the instrument scales are not correctly positioned or the instrument is damaged. The maximum and minimum readings are recorded by two small steel markers which are sprung into the capillary tube so that they can slide, but only if a force is applied to them, either by being pushed by the mercury or under the influence of an external magnet. Before a new maximum or minimum reading can be taken, the thermometer must be reset