Daniel Gabriel Fahrenheit

Temperature Scales (Daniel Gabriel Fahrenheit)

By the early 1700s, at least 35 different temperature scales had been proposed. At that time, a Dutch instrument maker by the name of Daniel Gabriel Fahrenheit became famous for his mercury thermometers. The Fahrenheit scale he developed is still the most widely used temperature scale in the United States.

The problem that Fahrenheit faced is still a common one. It is easy to make relative measurements, such as determining that one object is hotter than another. But it is much harder to make absolute measurements, such as determining the temperature of an object on an absolute scale.

The approach Fahrenheit took to this problem is still used for most instruments today. Fahrenheit calibrated his thermometer against a pair of references: body temperature and the lowest temperature he could achieve by adding salt to ice water. On this scale, the temperature of ice by itself is 32^oF and the temperature of boiling water is 212^oF.