Thermometer – Mercury Rising

Early HistoryThe first thermometers were called thermoscopes and while several inventors invented a version of the thermoscope at the same time, Italian inventor Santorio, Santorio was the first inventor to put a numerical scale on the instrument. Galileo Galilei invented a rudimentary water thermometer in 1593 which, for the first time, allowed temperature variations to be measured. In 1714, Gabriel Fahrenheit invented the first mercury thermometer

Thermometers measure air temperature. More specifically, this device measures the air’s heat content. The idea of “mercury rises” actually refers to traditional thermometers, which use liquid to generate readings. Heat causes the liquid within the thermometer to expand and travel up and down the tube. Temperatures are measured in degrees Celsius or degrees Fahrenheit, depending on location.

Official thermometers used for keeping weather records, measure the temperature about 5 feet above the ground, usually within a specified shelter. This is important because wind and environmental effects, such as topography, or shade and shadows, can skew thermometer readings.

Types of thermometers:

Liquid-in-glass thermometer: glass tube filled with liquid (often mercury or alcohol) that expands/contracts with air temperature

maximum thermometer: usually are liquid-in-glass thermometers that record maximum observed temperature

minimum thermometer: usually are liquid-in-glass thermometers (use alcohol) that record minimum observed temperatures

Electrical resistance thermometers - measure temperature by measuring resistance in a wire radiometer - measures radiation emitted by an object