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 of Du Crest was commonly used in northern Switzerland, and only a few years ago aged people often cited air-temperatures in Du Crest degrees.

In 1749 Du Crest was condemned for political reasons to lifelong imprisonment, and during the seventeen years that he spent in the fortress at Aargau he published several papers on meteorology; he died in 1766.

Anders Celsius, professor of astronomy at Upsala, proposed in 1742 a scale with zero at the boiling-point of water (the barometer at 25 inches, 3 lines), and with 100 at the temperature of melting ice. Celsius's scale is sometimes confounded with the French centesimal scale now in use, through neglect to remember the inversion. The change to the modern centigrade was made by two scientists independently, Christin, of Lyons, and Märten Strömer, of Upsala. The Lyons savant worked out the same plan as Celsius independently and published his results in the local papers in 1743. He disregarded the barometric pressure but in other respects his thermometer did not differ from the mercury centigrade thermometer of France; Christin's instrument was known as the thermometer of Lyons. 6