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Hello, Heat is a commonplace concept, cups of coffee cool down,

microwaves reheat them, water boils at a hundred degrees and freezes on cold

winter nights, but for a thing of such apparent every day in us, it took a long time to understand what heat actually was.

It's a story of brewing vats and steam engines, fridges, thermometers, thermometers, thermodynamics and the heat death of the universe

and importantly it was the understanding and harnessing of heat that helped make the

modern world of industry engineering and technology.

With me to discuss the science of heat from the 17th century are

Joanna Haig, Professor of Atmospheric Physics at Imperial College London,

Hasuk Chang, Professor of Philosophy of Science at University College London, and Simon Schaefer, Professor of History of Science at University College London and Simon Schaffer

Professor of History of Science at the University of Cambridge and

fellow of Darwin College.

Simon Schaffer, we're going to concentrate on the developing science of heat from

the 17th century, but was there much theory

about it before then? Well in order to understand what begins to be said by

natural philosophers from the 16 1600s onwards about heat,

one has to recognize that the classical tradition, going back to the Greeks,

gave those philosophers an enormous range of resources to make sense of what he was.

As you said, heat is apparently a very domestic common phenomenon.

We're thinking of a world lit by fire in which the notion of heat was very often identified with a vast range of phenomena,

weakly linked candles, oil lamps, life itself obviously had something to do with heat.

...