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Abstract

Around 1800, many reputable scientists reported significant variations in the temperature of pure water boiling under normal atmospheric pressure. The reported variations included a difference of over 1 degree C between boiling in metallic and glass vessels (Gay-Lussac), and "superheating" up to 112 degrees C on extracting dissolved air out of water (De Luc). I have confirmed most of these observations in my own experiments, many of which are described in this paper. Water boils at the "boiling point" only under very particular circumstances. Our common-sense intuition about the fixedness of the boiling point is only sustained by our limited experience. http://www.ingentaconnect.com/content/stl/sciprg/2008/00000091/00000003/art00001?token=004f145747d05c5f3b3b4746664874253e7b517b592a6c4f582a2f433e402c3568263c2b66ac79f
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What is temperature, and how can we measure it correctly? These may seem like simple questions, but the most renowned scientists struggled with them throughout the 18th and 19th centuries. In Inventing Temperature , Chang examines how scientists first created thermometers; how they measured temperature beyond the reach of standard thermometers; and how they managed to assess the reliability and accuracy of these instruments without a circular reliance on the instruments themselves. In a discussion that brings together the history of science with the philosophy of science, Chang presents the simple yet challenging epistemic and technical questions about these instruments, and the complex web of abstract philosophical issues surrounding them. Chang's book shows that many items of knowledge that we take for granted now are in fact spectacular achievements, obtained only after a great deal of innovative thinking, painstaking experiments, bold conjectures, and controversy. Lurking behind these achievements are some very important philosophical questions about how and when people accept the authority of science.