The development history of thermometer

Thermometer was hot and cold degree of industrial automation instrument measuring object, the general temperature measuring instrument have detection and display of two parts. The earliest temperature measuring instrument, is an Italian Galileo was created in 1592. It is a big glass bulb with a slender neck, upside down in a cup with wine container, of which the spare part of the air, fine wine to face up to the internal jugular. When the outside temperature changes, internal jugular wine surface because of the air inside the glass bulb heat bilges cold shrink and then lifting, and high and low temperature can be said of the wine, actually this is without a dial indicator. In 1709, Germany's warren hite founded in the Netherlands for the first time scale, then he after years of degree study, made by 1714 to the freezing point of water is 32 degrees and the boiling point is 212 degrees, the middle is divided into 180 degrees temperature recorder of mercury, Fahrenheit is still used today. Was taken in 1742, Sweden, west uz made another mercury thermometer, thermometers to the freezing point of water is 0, the boiling point as 100 degrees. By 1745, the Swedish Linnaeus to reverse the two fixed point, this kind of thermometer is the centigrade thermometer are still used today. As early as in 1735, there was a man who tried to use the principle of metal bar is heated expansion, thermometer, to the end of the 18th century, the bimetallic thermometer; In 1802, Charles's law established, gas thermometer has been improved and the development, its accuracy and temperature range than the mercury thermometer. In 1821, the German seebeck discovered thermoelectric effect; That same year, Britain's David found the regularity of metal resistance change with temperature, came after the thermocouple thermometer and thermal resistance thermometer. In 1876, Germany's Siemens, made the first platinum resistance thermometer. International modern general scale is in 1967 the 13th international conference through the right degree, in 1968 the international practical temperature scale. It takes 13 pure substance phase transition point, such as hydrogen triple point, namely the hydrogen solid, liquid, gas three coexistence point ( - 259. 34℃) ; Three-phase point of water ( 0. 01℃) And gold freezing point ( 1064. 43℃) As fixed point, such as define replicate our temperature of thermodynamics.