The book A History of PI by Petr Beckmann (1971) is what I call a role-model book, the type of book I would love to write myself.
Apart from giving a nice step by step history of the mathematics behind pi, starting with Mesopotamia and ending with the current period of modern computing, it also contains quite a lot of interesting information about the history of mathematics, especially in the context of mathematicians whose names every mathematics, engineering, and physicist student will be familiar with, such as Euclid, Archimedes, Newton, Laplace, and Lagrange.
And Mr. Beckmann doesn’t stop there. He also seems to enjoy interjecting some of his opinions about history. For example, consider how he demonstrates his disdain for the Roman Empire:
Rome was not the first state of organized gangsterdom, nor was it the last; but it was the only one that managed to bamboozle posterity into an almost universal admiration.
It’s certainly a book that goes well beyond your typical history of mathematics!
Anyway, it’s a lovely little book, and for me, it’s not just an afternoon read which tells the fabulous story of pi, it’s also a book which I am using as a template for one of my writing projects, the story behind the WHO’s Definition of Health.