I’ve been trying to learn a bit about classical *thermodynamics*, using Fermi’s lecture notes which are available as a low-cost Dover reprint.

That’s partly just because the subject has always been a bit mysterious to me and I would like to understand it better, but also because the Second Law of thermodynamics often gets invoked in environmental discussions – and I wonder whether it is being used accurately. (See this blog post for extended discussion about that.)

As a mathematician, I expected the discussion of thermodynamics to be *statistical*, heavily engaged with probability theory. But the main text of Fermi’s book is not about statistical mechanics at all. Instead, it is about *classical* thermodynamics; the nineteenth century theory that attempted to quantify the properties of that mysterious fluid, “heat”, and its transmission from one body to another. Continue reading