Daniel Gabriel Fahrenheit divisible into many fractions. It is because of the scale's redefinition that normal body temperature today is taken as 98.6 degrees, whereas it was 96 degrees on Fahrenheit's original scale. The Fahrenheit scale was the primary temperature standard for climatic, industrial and medical purposes in English-speaking countries until the 1970s, nowadays replaced by the Celsius scale long used in the rest of the world. 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
Mercury-in-glass thermometer was to use the condition of melting and not that of freezing. The experiments for reaching a good calibration of his thermometer lasted for 2 winters. By performing the same experiment over and over again, he discovered that ice always melted at the same calibration mark on the thermometer. He found a similar fixed point in the calibration of boiling water to water vapour (when this is done to high precision, a variation will be seen with atmospheric pressure; Celsius noted this). At the moment that he removed the thermometer from the vapour, the mercury level climbed slightly. This was