1686-1736


German physicist, who was born in Poland, but after 1701 lived in Amsterdam. He invented the mercury thermometer and introduced the Fahrenheit scale, still used in the U.S. today.

Fahrenheit used body temperature (90°F) and ice/salt (0°F) as fixed reference points, with the freezing point of water awarded a value of 30° (later revised to 32°).

Using his thermometer, Fahrenheit was able to determine the boiling points of liquids and show that liquids other than water also had fixed boiling points that varied with atmospheric pressure.