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
Six's thermometer the mercury, and returning it to the horizontal. The Six's thermometer is known for separations in the mercury column, in particular after shipment, though accidental knocks have been known causes as well. Separations can usually be corrected by swinging the thermometer as is done to reset a mercury clinical thermometer; the centrifugal force forces the mercury together again. Should a marker become partly buried in the mercury, it can either be pulled up again with the magnet or exposed to an extreme temperature that leaves the marker uncovered. If a strong external magnet is used to pull up the markers