On May 24, 1686, Daniel Gabriel Fahrenheit is born in Gdańsk, Poland. Fahrenheit later became a renowned physicist who would go on to invent a mercury thermometer that vastly improved the precision in which things like body temperature and the boiling point for water are measured. He would also create the temperature scale that still bears his name.
Fahrenheit’s path to success was marked by tragedy. In 1701, when he was just 15, his parents died after accidentally eating poisonous mushrooms. Orphaned, he and his siblings were placed under guardianship.
Fahrenheit’s guardians sent him to Amsterdam to work as a bookkeeper’s apprentice. But he was more interested in other pursuits, namely physics and the making of a more reliable and precise thermometer.
At the time, the Florentine thermometer, which consisted of a glass tube and bulb filled with alcohol, was one of the first thermometers to use the expansion and contraction of liquid to measure temperature. But its readings were imprecise.
Fahrenheit passionately took on the challenge of creating a better thermometer, but he fell into debt funding his experiments. His guardians, who were legally liable for his debts, became so furious about it that they had a warrant issued for Fahrenheit’s arrest.
Fahrenheit fled the Netherlands in 1707 and traveled through Germany, Sweden, Poland and Denmark, where he not only escaped arrest but met with other great scientific minds. (He repaid his debt in 1710.) During this time, Fahrenheit began experimenting with mercury instead of alcohol in his thermometers. Mercury’s high boiling point made it more amenable to measuring a wider range of temperatures. By 1714, he had created the mercury thermometer.
About a decade later, he introduced the temperature scale that bears his name. Unlike other scales at the time, the Fahrenheit scale was not based on the freezing and boiling points of water. Instead, Fahrenheit chose 96°F as the temperature of the human body and 0°F as the freezing point for a solution made of water, salt and ice. The top end of the scale was later revised to 98.6°F.
Fahrenheit passed away on September 16, 1736 at the age of 50 from what was believed to be mercury poisoning. Six years after his death, Anders Celsius developed a new temperature scale. The Celsius scale has been adopted as the temperature reading of choice by every major country in the world, except the U.S. where Fahrenheit’s scale remains steadfastly in place.
