History of Time

Timekeeping before timezones

Timekeeping today is largely taken for granted. There are clocks, of all sorts, all around us 24/7 that we can generally trust to be accurate to within the hour. 

This wasn’t always the case, in fact for most of history it wasn’t the case. For a long long time, time was kept very local. 

There might be a sundial or a water clock in a community, which everyone relied on to get rough estimates of what time it was.

A public Sundial in Suffolk with the Latin phrase: I only count the sunny hours.

The knocker-upper

Often it wasn’t even that sophisticated and people would rise for work in the morning as the sun rose, and go to bed as it got dark. It was a big enough problem that specialist jobs had to be made, as standardised work hours became more and more common, just to make sure people showed up for work on time.

The most common one was the ‘knocker-upper’, where a local person would be paid to carry a big stick around town and knock on people’s windows until they woke up.

A knocker-upper at work, they’d usually earn sixpence a week for their services to time keeping

Timekeeping At Sea

At sea it was often more complicated. Sailors would make games of counting how many times they saw the sun rise and compete with other ships on the same route to see who could move the quickest by counting the days of travel that way. There was also ‘dead-reckoning’, which was a means of navigating by looking at the stars and how they moved. Captains also used this to determine, on really long voyages, roughly what month it was. Although Dead reckoning isn’t used for time keeping at all anymore, and is notoriously unreliable, modern Captains, Skippers and Pilots are still taught the practice as a fall-back should all else fail.
A knocker-upper at work, they’d usually earn sixpence a week for their services to time keeping

GMT - Greenwich Mean-Time - The First Timezone

Greenwich Mean Time was the first effective ‘timezone’ in existence, one of a family of timezones created by the British Railway Association way back in the 19th century as a way to try to organise train arrival and departure times by using standardised time zones. GMT was in use even before Sir Sandford Fleming made his suggestion for dividing up the world into 24 time zones, which is incidentally why it’s treated as the baseline ‘+0’ for international time zones today.

If you look at some really old public clocks you might find they have extra hands that don’t seem to serve a purpose, that’s a relic of the early days of when GMT was first introduced; where public clocks would show the local time and GMT (or Railway Time as it was known at the time). It was quickly dropped, however, as it just led to lots of confusion over what time it was.

An old clock in Bristol showing Railway time as well as local time.

UTC - Coordinated Universal Time

Coordinated Universal Time, or just UTC for short, is a much later invention that was developed in 1963 as a more accurate alternative to GMT. The idea of UTC is to cut away the needless complexity of having many different time zones with different names and standards to use one common standard based on International Atomic Time (TAI), which uses atomic clocks to provide extremely precise time measurements via an array of 400 atomic clocks (which are clocks that measure time based on how long it takes an electron to to orbit an atomic nucleus) placed at different points around the globe.

The problem is… the alternatives have been around much longer, so in an effort to make one unified system that avoids confusion, UTC instead just creates more confusion. There’s also a problem where it’s actually too accurate in some way. It tends to create ‘leap seconds’ caused by the earth physically slowing down in its rotation slightly, plus it doesn’t adjust for daylight savings which makes it pretty useless in countries that observe systems like BST (British Summer Time, GMT+1). And that’s before we even get started on the politics of countries that want to dictate their own time zones!

So while it’s a neat idea, it’s maybe not the most practical for the average person… unless you don’t actually know the local alternative, in which case it’s a handy tool to get a rough idea what time it is in different places around the world.

A map of the UTC timezones with the older (sometimes still used) time zones boundaries overlaid onto it. Notice how badly off it is in some cases (and how weird China is).