2. Time Zones

3. in early days everyone set their clocks according to the sun - it was noon (12:00 p.m.) when the sun was at its highest point (its "zenith") in the sky

4. In larger communities, the military often would fire off a gun to signal this occurrence and everyone would reset their watches; or, they would listen for the tolling of the clock in town hall

5. because the length of daylight changes, this would not be exactly 24 hours, from noon to noon as businesses spread from region to region and railways and communication became more widespread, this use of solar time became very difficult as each town would have a slightly different solar time (because the sun is not overhead all places at the same time)

6. in 1886 the international community adopted a series of measures to solved business, communication and navigational problems at a huge conference in Berlin (this was when all of Europe was at peace - a rare occurrence - an international agreement could be possible)

7. A Canadian, Sir Sandford Fleming, had devised the notion what became known as "standard time", which depended on a consistent system of latitude and longitude

8. in 1886 the world agreed that O˚ longitude should pass through Greenwich, England (outside London) as this was where a very important observatory was located - this is called the Prime Meridian it was further agreed that the world would be divided into 24 equal time zones (as convention had 24 hours in a day)

10. since the world is round, there would be therefore 360 0 of longitude and therefore each time zone would be 15 0 wide (360/24 = 15)

11. In each of these time zones everyone would adopt the same time and as you crossed from one time zone to another you changed your watch by one full hour

12. Time Zones

15. This was a huge improvement on the old system and it was quickly adopted The agreement also allowed for nations to alter the borders of each time zone somewhat so that places that have a lot to do with one another could be in the same time zone for convenience sake There were some other variations as well, eg. Newfoundland time

16. If I could travel around the earth (to the east) in an instant I would cross 24 time zones. Each time I would cross a time zone I would move my clock up one hour. When I get back to where I started I would be one DAY ahead of everyone else! This happened to a famous explorer by the name of Ferdinand Magellan. In order correct this problem The International Dateline was created. It is an imaginary line that simply tells travelers to adjust their calendars. If you are traveling east and cross the dateline you go back one day. The dateline is the 180 degree line of longitude, directly opposite the Prime Meridian.

17. Monday Sunday

18. The End!