Fahrenheit, Gabriel Daniel (1686-1736), a German physicist. In 1714, he devised the Fahrenheit scale for measuring temperature and originated the use of mercury instead of alcohol in thermometers. He is also credited with discovering that a liquid's boiling point changes with the atmospheric pressure. Fahrenheit was born in Danzig (now Gdansk, Poland). He lived in Holland and England for many years, working as an instrument maker. Fahrenheit was elected to England's Royal Society in 1724.