One other thing. It's disappointing to read a chapter on why the sky is blue without once coming across John Tyndall's name. On page 41, Phil credits Lord Rayleigh with discovering that air molecules scatter blue light preferentially "in the mid-1800s." But Rayleigh was born in 1842, so he was only a kid in the mid-1800s. In fact, it was the Irish physicist John Tyndall who first proved experimentally that blue light is scattered more than other colours. That was in 1869, two years before Rayleigh's first publication on the same subject.

In his New Guide to Science, the late great Isaac Asimov correctly credits the Irishman with the discovery and calls the phenomenon The Tyndall Effect.

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