Caloric theory

The caloric theory is an obsolete scientific theory that heat consists of a self-repellent fluid called caloric that flows from hotter bodies to colder bodies. Caloric was also thought of as a weightless gas that could pass in and out of pores in solids and liquids. The "caloric theory" was superseded by the mid-19th century in favor of the mechanical theory of heat, but nevertheless persisted in some scientific literature—particularly in more popular treatments—until the end of the 19th century.^[1]

^ The 1880 edition of A Guide to the Scientific Knowledge of Things Familiar, a 19th century educational science book, explained heat transfer in terms of the flow of caloric.

[1] The 1880 edition of A Guide to the Scientific Knowledge of Things Familiar, a 19th century educational science book, explained heat transfer in terms of the flow of caloric.

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