From a Wall Street Journal story by Keith Houston headlined “Five Best: Books on Great Inventions”:

The History of Clocks & Watches
By Eric Bruton (1979)

1. We do not know who first invented the clock. Of course, the same goes for many other venerable inventions—the originators of writing, paper, movable type and cast iron are similarly obscure—but the humble clock is so familiar that it is shocking to learn how little we know about its genesis. Happily, once the dark ages of the clock are dispensed with, Eric Bruton has a lot of recorded history to work with.