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From KQED.

Thank you. very from kQED. From KQED. From KQED, public radio in San Francisco, I'm Nina Kim.

David Rooney is fascinated by clocks, the son

of a clockmaker and former curator of timekeeping at the Royal Observatory in Greenwich.

Rooney has studied everything from sundials to clock-based GPS satellites and finds

that marking time has played a major role in shaping civilization and in wielding power.

For thousands of years, time has been harnessed, politicized, and weaponized, writes Rooney in his new book titled About Time.

He'll spend a little time with us after this news.

This is Forum. I'm Nina Kim. The next time you watch the seconds taking away on a clock face and start to get nervous about how you're spending your time.

Consider that it's no accident.

David Rooney says timekeepers across centuries have wielded clocks to impose morality or controlled behavior, while others have used it to secure power.

In his new book, About Time, A History of Civilization in 12 clocks, Rooney looks at how

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