The thermometer is an object used all over the world and it is used to measure the corporal or object temperature, but they were first called thermoscope.
The first thermoscope was invented by Galileo Galilei in 1592 and it was a glass tube with a liquid of alcohol and water that was closed with a small ball. They had an open side and when the ball was hot, the liquid went up through the tube depending of the temperature.
Then, in 1714 Gabriel Fahrenheit invented the first thermometer with mercury. Nowadays they continue being used in some countries but in many others they were prohibited because it was pollutant like in Spain and it has been replaced by others as gas, resistance or foxgloves, The most famous and modern is the digital thermometer which are mainly used in hospitals.
To measure the temperature, scales are used: The in centigrade (°C), called Celsius from 1948, the Fahrenheit (°F) for Daniel Gabriel Fahrenheit, Réaumur (°R) for René-Antoine Ferchault and Kelvin (TK), and it is the scale of temperature of the International System of Units.
By Noemi Olivares Rodríguez