phlogiston theory


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phlogiston theory

(flōjĭs`tŏn), hypothesis regarding combustion. The theory, advanced by J. J. Becher late in the 17th cent. and extended and popularized by G. E. Stahl, postulates that in all flammable materials there is present phlogiston, a substance without color, odor, taste, or weight that is given off in burning. "Phlogisticated" substances are those that contain phlogiston and, on being burned, are "dephlogisticated." The ash of the burned material is held to be the true material. The theory received strong and wide support throughout a large part of the 18th cent. until it was refuted by the work of A. L. Lavoisier, who revealed the true nature of combustion. Joseph Priestley, however, defended the theory throughout his lifetime. Henry Cavendish remained doubtful, but most other chemists of the period, including C. L. Berthollet, rejected it.
References in periodicals archive ?
By demonstrating that combustion was really a process that combined materials with oxygen, Lavoisier disproved the phlogiston theory, established the basic law of conservation of matter, and opened the door to our modern understanding of chemistry.
Centered on the transition from the phlogiston theory of combustion to the oxygen theory of chemistry, the Chemical Revolution involved a transformation in the ontology, epistemology, methodology, language, instruments, and institutions of chemistry.
1988: "Farewell to the Phlogiston Theory of Conditionals".
For years, natural scientists believed in the phlogiston theory.
One of the important differences between this case (and folk psychology on the deep conception) and the pot/rock case is that the Phlogiston theory makes specific claims about the underlying causal processes responsible for the manifest regularities concerning combustion.
As Debus points out in his postscript, the phlogiston theory had deep roots in Paracelsianism.