Why does Jonathan Betts say clocks run clockwise?

Jonathan Betts said early clock dials were built to imitate sundials, with the hour hand standing in for the sun's shadow. Because those clocks were made in the Northern Hemisphere, the hand copied the direction a sundial shadow moves there. Betts suggested that if clockwork had first been developed in Australia or South America, clockwise would run the other way.

• Early dials showed 24 hours to mirror the sundial, and the 12-hour dial came about a century later.
• Betts said the sundial stayed the most accurate everyday timekeeper for most people until about the 19th century.

Source: our own transcription of the episode. The full conversation is on In Our Time (2026-10-12). Read the whole episode summary →

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