Learn more about the thermometer

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En savoir plus sur le thermomètre

The thermometer is an instrument for taking the temperature used in various trades, cooking , industry, medicine, etc. You probably have a medical or room thermometer at home. In short, in general, the majority of human beings are familiar with the thermometer, you are most certainly one of them. The specialists in temperature measurement offer you a short course on the definition and history of the thermometer could help you better understand its usefulness, its functioning and its uses. Once upon a time… The thermometer.

The great definition of the thermometer

According to the French encyclopedia or dictionary you are used to consulting, here is what you can find to define the thermometer:

  • According to Larousse, the definition of a thermometer simply says that it is a device intended to measure temperatures.
  • The Robert goes further by giving a more complete definition of the thermometer: the thermometer is an instrument intended for measuring temperatures, generally thanks to the expansion of a liquid or a gas, like the mercury thermometer or helium. There is also the medical thermometer which is intended to indicate body temperature.
  • Wikipedia, which is more of an encyclopedia than a dictionary, offers the following definition of a thermometer: a thermometer, from the ancient Greek thermós (“hot”) and metron (“measurement”), is a device that makes it possible to measure and to display the temperature value. This is the field of study of thermometry. Developed during the 16th and 17th centuries, the thermometer is used in different fields. The applications of professional thermometers are multiple, in meteorology, in medicine, in the kitchen, for cooking, for regulation, in industrial processes, measurement of the outside or inside temperature of factories, etc.

The definitions of the thermometer are therefore varied depending on the point of view from which one adopts. The experts at Thermometer.fr, the leader in temperature measurement, present their own definition of a thermometer.

The thermometer is an instrument for measuring and reading temperature. The temperature measurement and its accuracy, in degrees Celsius or in Fahrenheit, is done via two essential components:

  • a temperature sensor in which a change occurs (in the bulb of a glass mercury thermometer for example),
  • a tool to convert this change to a numerical value (like the scale of a mercury-in-glass thermometer).

The thermometer is used in technology and industry to monitor processes, in meteorology, in the food industry, in medicine and in scientific research. It can also be used at home, especially to check body temperature.

The history of the thermometer

If the thermometer today allows us to know how to dress or cook the Christmas turkey, in antiquity its ancestor the thermoscope already observed the temperature variations. In 1592, Galileo worked for example on his own research, thanks to his makeshift thermoscope which contained wine in a sealed glass tube. Depending on the time of day, especially when it was colder, the air took up less space and the level of wine rose.Galileo's thermoscope, based on the principle of Archimedes' thrust and the expansion of matter, was born

In 1612, Sanctorius drew inspiration from and diverted the work of his friend Galileo to create the medical thermoscope; the temperature measurement is the same, except that the patient must put a sealed glass ball in their mouth. Of course, these measurement systems were very inaccurate.

Forty years later, Ferdinando II de' Medici, brought ethanol to the thermoscope, which he dyed red to make it visible while remaining faithful to thermoscopes, and graduated the Galilean glass tube, which then made it possible to quantify the temperature. The first thermometer is born.

In 1717, Gabriel Fahrenheit replaced ethanol with mercury and proposed a first temperature scale, replaced almost everywhere in the world by that of the physicist André Celsius in 1742. This scale of temperature widely used, you know it for having studied it in college: 100° corresponded to the freezing point of water, and 0° to its boiling point.

Today, scientists from all walks of life have created different models of thermometers (scaling, probe or infrared thermometer or thermometer with laser sighting), some thermometers are digital without contact, others with tips, etc. to meet the needs of individuals and for professionals.

You can follow all the advice of the experts at Thermomètre.fr to properly choose your thermometer, in particular according to its characteristics.