Why Do Clocks Run Clockwise?

Authored by mentalfloss.com and submitted by Mass1m01973

It’s a total cop-out to say that clocks run clockwise because that’s how clocks run...but it’s also kind of true. The modern convention is no arbitrary design choice, but rather a direct adaptation of the original timepiece: the sundial.

Way back when, a sundial told time by casting a shadow with its gnomon around a circular platform. In the northern hemisphere, that meant the shadow moved (to use a compass analogy) from north to east to south to west as the sun traveled, and when mechanical clocks started appearing, they were designed to operate in a similar fashion. Which begs the question, would clocks run the opposite direction if we’d based them on sundials in the Southern Hemisphere? Yes! Sundials work counterclockwise below the equator, and we’d be reading our watches totally differently if modern clock-makers had used them as an example.

If you’re already into the old-school style of an analog display, the fact that it's a throw-back to even older time-telling devices makes the design that much cooler.

barath_s on September 24th, 2018 at 12:42 UTC »

TIL: The time told by a sundial can differ from that told by a clock due to the earth's tilt and elliptical orbit. The difference is the same all over the globe and can go up to ~1/4 hour.

And in the early days, this difference was used to adjust clocks to the solar time, rather than vice versa.

PussyStapler on September 24th, 2018 at 12:38 UTC »

Prior to the term clockwise, people used to say sunwise. We also used terms like deosil and widdershins for clockwise and counterclockwise

barath_s on September 24th, 2018 at 12:37 UTC »

Apparently you can create digital sundials that use no electricity or moving parts