Who developed the theory of standard time zones?

Answer 1

Time!

Upper Half of Clock, Theodor Horydczak, photographer, circa 1920-1950.
Washington as It Was, 1923-1959

On November 18, 1883, four standard time zones for the continental U.S.A. were introduced at the instigation of the railroads. At noon on this day the U.S. Naval Observatory changed its telegraphic signals to correspond to the change. Until the invention of the railway, it took such a long time to get from one place to another that local "sun time" could be used. When traveling to the east or to the west, a person would have to change his or her watch by one minute every twelve miles.

When people began traveling by train, sometimes hundreds of miles in a day, the calculation of time became a serious problem. Operators of the new railroad lines realized that a new time plan was needed in order to offer a uniform train schedule for departures and arrivals.

Since every city was using a different time standard, there were over 300 local sun times to choose from. The railroad managers tried to address the problem by establishing 100 railroad time zones, but this was only a partial solution to the problem.

Fast Mail, Northern Pacific Railroad, Thomas A. Edison, Inc., James White, producer, July or August 1897.
Inventing Entertainment: The Edison Companies

The fact remained that the different railroad lines were using time schedules that varied from each other and from the cities they passed through, causing considerable befuddlement. Where railroad lines using different time zones intersected with each other, or with cities using different time standards, travelers were especially confused.

During the mid-nineteenth century, people throughout the world had experimented with methods of standardizing their clocks. In 1830 the U.S. Naval Observatory was created to cooperate with Great Britain's Greenwich Observatory to determine time based on astronomical observations. Accurate sea navigation based on the calculation of latitude and longitude, depended on accurate timekeeping.

Samuel Morse's invention of the telegraph made it possible to coordinate time signals over long distances. In the 1840s, the Royal Greenwich Observatory established an official standard time for all of England, Scotland, and Wales. The U.S. Naval Observatory was responsible for keeping official time in the United States.

Burlington Route, Rand McNally and Company.
For Chicago, Burlington & Quincy Railroad Company, 1897.
Railroad Maps, 1828-1900

U.S. railway managers were the first to adopt a plan to simplify calculation of time for the convenience of travelers within the continental United States. They agreed that four time zones would be adopted: Eastern, Central, Mountain, and Pacific Time. Local times would no longer be used by the railroads. The American Railway Association obtained the cooperation of city governments served by the railroads. The U.S. Naval Observatory agreed to make the change.

At twelve o'clock noon on November 18, 1883, as Greenwich Mean Time (GMT) was transmitted, the U.S. Naval Observatory began signaling the new time standard. Authorities in major cities and managers of the railroad reset their clocks. All over the United States and Canada, people changed their clocks and watches in synchronization with their zone's standard time. In one moment the many different standards of time that had caused conflict and confusion, were resolved into four simple standards.

A year later, on November 1, 1884, the International Meridian Conference in Washington, D.C. agreed to establish international zones according to the same system. GMT was considered the "time zero," and the twenty-four standard meridians marked the centers of the zones. The International Dateline was placed along the 180 degree meridian in the Pacific Ocean. Around the world, clocks were reset to reflect the new system of timekeeping. By the time travelers began to rely on the airplane for travel, they had become accustomed to the system. Today, travelers think little of crossing more than one time zone in a trip of a few hours.

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