Mercury-in-glass thermometer ushered in a new era of accuracy and precision in thermometry, and is still to this day regarded as one of the most accurate thermometers available. The thermometer was used by the originators of the Fahrenheit and Celsius scales. Anders Celsius, a Swedish scientist, devised the Celsius scale, which was described in his publication "The origin of the Celsius temperature scale" in 1742. Celsius used two fixed points in his scale: the temperature of melting ice and the temperature of boiling water. This wasn't a new idea, since Isaac Newton was already working on something similar. The distinction of Celsius
Scale height scale height of Earth's atmosphere is therefore 1.38/(4.808×9.81)×10 = 29.26 m/deg. This yields the following scale heights for representative air temperatures. These figures should be compared with the temperature and density of Earth's atmosphere plotted at NRLMSISE-00, which shows the air density dropping from 1200 g/m at sea level to 0.5 = .125 g/m at 70 km, a factor of 9600, indicating an average scale height of 70/ln(9600) = 7.64 km, consistent with the indicated average air temperature over that range of close to 260 K. Note: Approximate atmospheric scale heights for selected Solar System bodies follow. Scale height In