This has been bugging me quite a bit recently but when did it become apparant that the world operated in different timezones? I appreciate that it has always operated like that but when did contemporaries realise this, presumably it must have taken awhile to confirm (till radio) but im still curious. For instance did the Romans knew that they operated over various GMT zones. Anyone got any answers?

This has been bugging me quite a bit recently but when did it become apparant that the world operated in different timezones? I appreciate that it has always operated like that but when did contemporaries realise this, presumably it must have taken awhile to confirm (till radio) but im still curious. For instance did the Romans knew that they operated over various GMT zones. Anyone got any answers?

??? time zones are arbitrary...

Yes, i got that. So what im asking is when did timezones start coming into play? and did say Genghis khan realise he was ruling over different timezones or did he think when it was 1pm in china it was 1pm in Baghdad.

Yes, i got that. So what im asking is when did timezones start coming into play? and did say Genghis khan realise he was ruling over different timezones or did he think when it was 1pm in china it was 1pm in Baghdad.

i guess by travelling with horses you dont actually see that the sun shines on earth from different angles depending on where you stand on it.

but i'm quite sure early mathematicians allready knew of the phenomenon.

It would have been a logical conclusion from realising the earth is round and the solar system is heliocentric. It also woulda been fairly easy to demonstrate experimentally.

My guess is the Chinese knew first but I'd be curious of the details.

You wouldn't need to know about heliocentrism. Knowing that the earth is round would be enough. So I suppose it must have been known to the ancient Greeks at the very least. But it only became a practical issue in the nineteenth century, with the invention of railways and the telegraph. In Britain, for example, every town was its own time zone, with clocks showing midday at the moment when the sun was overhead. This had to change with the arrival of the railways, because the trains all had to run on a single timetable with a single time. "Railway time" was therefore introduced across the country, although some places held out against it. In fact Christ Church in Oxford still (officially) does, which is why the clock on Tom Tower is five minutes slow.

Hang on yeah, you're right. Heliocentrism wouldnt matter... what was I thinking.

Even well into the 1800's, different towns in England had slightly different times, as places even a few miles away differend by 5/10 minutes until GMT was established accross the whole of the UK.

In fact it was even later than the 1800s - most railways began using London time as standard in the 1840s. It wasn't until 1880 that GMT was made standard throughout Britain, and thus it remained until 1916 when BST (GMT+1) was introduced for half the year. In fact it's often forgotten that between 1939 and 1945 Britain was an hour earlier all the time (GMT+1 in winter and GMT+2 in summer), and between 1968 and 1971 it was on BST all year round.

Heh, I was thinking about this the other day! I came to the conclusion that it couldn't have become apparent until we had the capability to travel farther than a single time zone in a single day, so, in other words, not before industrialization.

It reminds of an anecdote in USSR.

One day, Brejnev calls for a gathering of the leading soviet scientists, and say "I really don't like these time zones. I want you to find a solution to get rid of time difference, so everyone on Earth lives by the same time".

The scientists are not pleased, and afraid, they don't know how to answer... Then one gather is courage and says "Camrad Brejnev, it is not possible. Time difference is a law of nature, and as long as Earth will rotate, we will have time difference."

And Brejnev answers "really? That's really annoying. Yesterday I called Indira Gandhi to wish her a nice birthday, and she told me it was the day before, I today I called Reagan to wish him a quick recover after the assassination attempt, and I discovered it is planned for tomorrow".

It reminds of an anecdote in USSR.

One day, Brejnev calls for a gathering of the leading soviet scientists, and say "I really don't like these time zones. I want you to find a solution to get rid of time difference, so everyone on Earth lives by the same time".

The scientists are not pleased, and afraid, they don't know how to answer... Then one gather is courage and says "Camrad Brejnev, it is not possible. Time difference is a law of nature, and as long as Earth will rotate, we will have time difference."

And Brejnev answers "really? That's really annoying. Yesterday I called Indira Gandhi to wish her a nice birthday, and she told me it was the day before, I today I called Reagan to wish him a quick recover after the assassination attempt, and I discovered it is planned for tomorrow".

Funniest part is how it was already planned to be an unsuccessful assassination.

Lolz love the "today I called Reagan to wish him a quick recover after the assassination attempt, and I discovered it is planned for tomorrow" part

What, the punchline? That's traditionally considered the most enjoyable part of most jokes.

What, the punchline? That's traditionally considered the most enjoyable part of most jokes.

:lol::lol::lol:

... today I called Reagan to wish him a quick recover after the assassination attempt, and I discovered it is planned for tomorrow".
Funniest part is how it was already planned to be an unsuccessful assassination.
:rotfl:

This discussion reminds me of a conversation I had a couple of years ago with a friend from Salt Lake City. He and I are in the same time zone (Mountain), but that obviously slipped his mind. We were chatting in the middle of the night, and he asked, "What time is it in Canada now?" :eek:

You just need to move a clock east-west to prove that the world has different "time zones".

You can also use the time on that clock as an "absolute time" and compare it with local time in order to determine longitude.

This has apparently been known for a long time.
Accoriding to this site (http://www-groups.dcs.st-and.ac.uk/~history/PrintHT/Longitude1.html) "Hipparchus proposed a zero meridian through Rhodes, with east/west distances from this line determined by comparing the local time of a place with an absolute time"
And Hipparchus lived ca. 190 – 120 BC so they knew about time zones already then!

From what I remember some Greek guy used the fact that the Sun is in a different position in the sky at the same time, in different geographical locations, to figure out how big the Earth is.

Aaaand some Canadian guy invented time zones.

Not very helpful, but there ya go ;)

I don't think time zones were ever "invented" so much as evolved de facto?