Joule, Thomson, and the birth of big science

Reblogged from carnotcycle:

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In early May 1852, in the cellar of a house in Acton Square, Salford, Manchester, two men began working a mechanical apparatus which consisted of the above hand-operated forcing pump attached to a coiled length of lead piping equipped with a stopcock at its far end to act as a throttle.

The two men were the owner of the house, 33-year-old James Joule, a Manchester brewer who was rapidly making a name for himself as a first-rate experimental scientist, and 27-year-old William Thomson (later Lord Kelvin), a maverick theoretician who was already a professor of natural sciences at Glasgow University.

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I know that I might be guilty of putting too much emphasis on the fancy / sci-fi / geeky fields in physics, as demonstrated by my recent post on quantum field theory. In order to compensate for that I want to reblog this excellent post by carnotcycle in order to demonstrate that I really like thermodynamics. And I mean good, old, phenomenological thermodynamics – pistons, steam engines, and seemingly simple machines (that look like exhibits at a steampunk convention). Classical thermodynamics is underrated (re geekiness) compared to pondering on entropy and the arrow of time or entropy as it is used in computer science. It is deceptively simple – you might think it is easy to understand the behavior of ideal gases and steam-powered engines. But isn't it that type of experiments that often baffles the audience in science shows on TV? The history of the research done by Joule and Thomson could give you a taste of that. I don't think it is intuitive why or why not a gas should cool when flowing to a region of lower pressure.