Invention

Time Zone

North America had more than 144 local times before the railroads replaced them with four.

United States · 1883

Before 1883, every city in North America set its own clocks by the local position of the sun.1 High noon in Boston arrived minutes before high noon in New York, which arrived minutes before high noon in Philadelphia. Estimates of the number of distinct local times across the United States range from 144 to several hundred.2

The railroads made this chaos dangerous. By the early 1880s, more than 53,000 miles of track operated according to at least eighty different internal timetables.3 A single junction served by multiple railroads might display a separate clock for each company, each showing a different time.

Sandford Fleming, a Scottish-born Canadian railway engineer, became an advocate for standardized time after missing a train in 1876 because of time confusion in a railroad timetable.4 He proposed dividing the world into twenty-four hourly zones, each covering fifteen degrees of longitude. William F. Allen, editor of the Traveler's Official Railway Guide, took Fleming's ideas and designed a practical system for North American railroads.1

On October 11, 1883, the General Time Convention met at the Grand Pacific Hotel in Chicago and voted to adopt Allen's plan.2

144

Estimated local times in use across North America before railroad standardization.

At noon on November 18, 1883, railroad clocks across the continent were reset. The day was called the Day of Two Noons because in several cities the clock struck twelve twice, once at the old local time and once at the new standard.3 Within a year, eighty-five percent of cities with populations over ten thousand had adopted standard time.5

The railroad companies had no legal authority to impose a new system of time. They simply did it, and most Americans complied because the trains were their connection to the wider economy.

Congress did not formally adopt the railroad time zones into federal law until the Standard Time Act of March 19, 1918.5 In 1884, twenty-five countries gathered at the International Prime Meridian Conference in Washington, D.C., and agreed to adopt Greenwich, England, as the zero-degree meridian from which global time zones would be calculated.4

Timeline

1876

Sandford Fleming misses a train and begins advocating for standardized time.

1883

North American railroads adopt four continental time zones on November 18.

1884

International Prime Meridian Conference agrees on Greenwich as the zero-degree meridian.

1918

U.S. Congress formally adopts railroad time zones into federal law.

Endnotes

1 Carlene Stephens, On Time: How America Has Learned to Live by the Clock (Boston: Bulfinch Press, 2002).

2 Library of Congress, "Whose Time Is It Anyway? A Brief History of Standardized Time Zones in the United States," In Custodia Legis, November 2024.

3 History.com, "Railroads Create the First Time Zones," November 18, 1883 entry.

4 Smithsonian Institution, "Sandford Fleming Sets the World's Clock," Smithsonian Magazine, November 15, 2013.

5 Standard Time Act, Pub. L. 65-106, March 19, 1918.