The origin of the thermometer ℉ and ℃ and relationship

The first thermometer is in 1593 by the Italian scientist Galileo ( 1564 ~ 1642) The invention. His first thermometer is only a glass tube exposure at one end, on the other side with walnut large glass bulb. When using heated the glass bulb first and then put the glass tube into the water. As the change of temperature, the water in the glass tube is mobile, based on what mobile can determine the change of temperature and temperature of high and low. Thermometer has the effect of heat bilges cold shrink so this kind of thermometer, is strongly influenced by the outside environment factors such as atmospheric pressure, so the measurement error is bigger. In 1714, and measured by mercury as material, creating more accurate thermometer. He looked at the water's boiling temperature, the temperature of the mixed water and ice, salt water and ice when the temperature of the mixture; After repeated experiments and approval, and finally to a certain concentration of the temperature of the salt water freezes at 0 ℉, the temperature of pure water freezes at 32 ℉, a standard atmospheric pressure, the water to boil at a temperature of 212 ℉, with ℉ Fahrenheit temperature, this is Fahrenheit. Fahrenheit is made after over 30 years, the Swede was taken, Theseus improved in 1742, warren hite thermometer calibration, he put the boiling point of water at 100 degrees, the freezing point of water as zero. Later his colleagues le meur numerical upside down again, the two temperature points become now the percentage of temperature, namely the Celsius temperature, expressed in ℃. Fahrenheit and Celsius temperature relationship is ℉ = 9/5 ℃ + 32, or 5/9 ℃ = ( ℉- 32) 。 Now multi-purpose Fahrenheit, British and American countries and the world in technology and the industrial and agricultural production, and most in our country, France and other countries are multi-purpose Celsius temperature.