Standard time

Historically, standard time was established during the 19th century to aid weather forecasting and train travel.

The adoption of standard time, because of the inseparable correspondence between longitude and time, solidified the concept of halving the globe into the Eastern Hemisphere and the Western Hemisphere, with one Prime Meridian replacing the various prime meridians that had previously been used.

During the 19th century, scheduled steamships and trains required time standardisation in the industrialized world.

The Santa Fe Railroad used Jefferson City (Missouri) time all the way to its west end at Deming, New Mexico, as did the east–west lines across Texas; Central Pacific and Southern Pacific Railroads used San Francisco time all the way to El Paso.

[3] In 1870, Charles F. Dowd proposed four time zones based on the meridian through Washington, DC, for North American railroads.

[6] The General Time Convention (renamed the American Railway Association in 1891), an organization of US railroads charged with coordinating schedules and operating standards, became increasingly concerned that if the US government adopted a standard time scheme it would be disadvantageous to its member railroads.

William F. Allen, the Convention secretary, argued that North American railroads should adopt a five-zone standard, similar to the one in use today, to avoid government action.

On October 11, 1883, the heads of the major railroads met in Chicago at the Grand Pacific Hotel[7] and agreed to adopt Allen's proposed system.

The members agreed that on Sunday, November 18, 1883, all United States and Canadian railroads would readjust their clocks and watches to reflect the new five-zone system on a telegraph signal from the Allegheny Observatory in Pittsburgh at exactly noon on the 90th meridian.

The daylight saving time portion of the law was repealed in 1919 over a presidential veto, but was re-established nationally during World War II.

[13] In 1999, standard time was inducted into the North America Railway Hall of Fame in the category "National: Technical Innovations.