Standard time and the day of two noons
Until the 1880s, every town kept its own time. The railways changed that, on a day that is still remembered.
Today we take it for granted that clocks in one region show the same hour. A little over a century and a half ago, they did not. Each town set its clocks by the sun, so noon in one place came a few minutes before or after noon in the next.
Local time#
This worked while people travelled slowly. If you walked or rode a horse, a few minutes of difference did not matter.
Railways changed everything. A train timetable that crossed many towns, each with its own time, was a nightmare. In North America, there were dozens of local times in use, and railways often kept their own, which made it confusing for travellers and dangerous for scheduling.
Time zones are introduced#
In 1883, the railways of the United States and Canada agreed on a system of standard time, dividing the continent into zones. On 18 November 1883, often called the day of two noons, clocks in many places were adjusted. In some towns, midday came twice, because clocks were set back to match their new zone.
Nothing was forced by law at first. The railways simply began to run on the new time, and cities followed because it was practical.
A world system#
The following year, in 1884, an international conference in Washington agreed to adopt the meridian passing through Greenwich in London as the zero point for longitude and time. This laid the foundation for the world's time zones.
Not everyone liked it#
Some people objected. They felt time should belong to the sun and local custom, not to the railways. Some places resisted for years. Eventually, the benefits were clear, and the rest of the world fell into line.
Why it matters#
Our shared hours are a human invention, created to solve a practical problem. Whenever people are connected more closely, they need to agree on common rules. Time zones were an early example of that.