Why do clocks go clockwise? A sundial reminder about standards

Ray Poynter, 31 January 2026

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Sometimes there is a reason why something happens the way it does; sometimes it is just a consequence of other factors.

Walking through a park in Australia recently, I stopped at a sundial. It was doing two ‘wrong’ things at once: the time did not match my watch, and the dial ran anticlockwise.

Both quirks are a useful reminder that many of our ‘obvious’ conventions are the product of geography, engineering, and standard-setting.

What I saw in Ballarat

The sundial was in Ballarat, in the Australian state of Victoria.

It looked perfectly conventional until you noticed two details: the hour markings progressed anticlockwise, and the shadow was not pointing at the same hour as local clock time.

Why the sundial showed the ‘wrong’ time

There are two straightforward reasons.

1. Daylight saving time. Victoria observes daylight saving time during summer. Clocks are set one hour ahead, but the Sun does not change its mind because governments do.
2. Longitude and standard time. A sundial tells local solar time for the specific longitude where it sits. Our everyday clock time is standardised to a reference meridian and time zone. If you are not exactly on that reference longitude, the local solar noon will not line up perfectly with 12:00 on the clock.

Before railways and telegraphs, many towns effectively ran on their own local time, set by the Sun. Once trains started moving fast enough for timetables to matter across distances, standard time became the practical solution.

Why this sundial runs anticlockwise

To make sense of the direction of a clock, imagine a simple stick in the ground and track the tip of its shadow through the day.

In the Northern Hemisphere, you face south to look towards the Sun’s arc. The shadow tip moves in a clockwise direction across the ground.

In the Southern Hemisphere, you face north. The Sun’s arc is on the other side of you, so the shadow tip moves in the opposite direction. On a horizontal dial, that produces an anticlockwise sequence of hour marks.

So what? Standards are useful, but they are not neutral

If the world’s reference point had been set in the Southern Hemisphere, we would still have a workable system, but some things would feel ‘reversed’.

The practical point is not to romanticise sundials. It is to notice the layers involved when we treat a convention as natural:

• Physics: shadows move because of the Earth–Sun geometry.
• Agreement: time zones, reference meridians, and daylight saving are social decisions.
• Power and history: which agreement becomes global is rarely random, and the consequences can persist.

What this means for insights work

In research and analytics, we live inside conventions: definitions, metrics, classifications, ‘standard’ questions, and default dashboards.

The consequence is that disagreements are often not about the numbers but about the standards underlying them.

My practical recommendation is to make standards visible:

• State the convention you are using (and why).
• Note what would change if a different convention were used.
• Be explicit about who benefits, and who carries the cost, when one standard becomes the default.

So Called ‘Best Practices’

One of my pet hates is when somebody tells me that we should do it their company’s way because that is best practice. Too often, the person I am speaking to has limited knowledge of the many options available or of the research supporting them. They know one way, the way their company does it, and they have been told it is ‘best practice’. Because I am often involved in projects designed to set standards, I often have to agree to use the term Best Practice, but I hope that on each occasion, I highlight why this particular option is currently considered best practice and the extent to which other options are valid.

A closing question

Where in your work are you treating a convention as a law of nature, when it is really just a standard that somebody chose?

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