In 1840, the Great Western Railway became the first to adopt London time, and most railroads soon followed suit.
How Railroads Created Time ZonesĮngland’s railroads also needed standardization for their timetables. Each town in England, however, continued to set its own clocks by the sun. In 1764, John Harrison perfected the use of clocks to determine a ship’s east-west position at sea. The Royal Observatory in Greenwich, England, established Greenwich Mean Time (GMT) in 1675 as an aid to mariners in determining longitude. This inconsistency was the impetus for standardization, made possible by the telegraph.Īnother mode of transportation-the sailing ship-inspired the earliest efforts to standardize time. The railroads had been struggling with 100 different local time zones of their own devising. 18, 1883-the “day with two noons”-most places in the continental United States adopted the system of four time zones originally known as Standard Railway Time. When your clocks “spring forward” or “fall back” with Daylight Saving Time, take a moment to observe the birthday of America’s standard time zones. “Sun time” differs by four minutes for every degree of longitude, making New York and Boston eight minutes apart. Estimates of the number of these local “time zones” range from 300 to 8,000 across the United States alone. ( Wikimedia Commons)ĭoes anybody really know what time it is? For our ancestors, the answer depended on where they were, with each town’s official clock-typically on a church or city hall-set by the sun, which would be overhead at noon each day. This map shows the railroads’ time zones five years earlier, in 1913. The Standard Time Act in 1918 formally established four US time zones.
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How to Find Your Ancestor’s US Military Records.The DST runs from 2 pm on the 2nd Sunday in March to 2 am on the first Sunday in November. The Daylight Saving Time (DST) is observed in the whole of US states and territories except in Hawaii, Puerto Rico, American Samoa, US Virgin Island, and Arizona (observed only in Navajo Nation). For instance, Howland Island and Baker Island use UTC-12:00 and are sometimes assigned Anywhere on Earth (AoE). The US also possesses outlying islands which do not observe any of the nine time zones. The US territories observe Samoa Time Zone (American Samoa), Atlantic Time Zone (US Virginia Islands and Puerto Rico), and Chamorro Time Zone (the Northern Mariana Islands and Guam). The state of Alaska observes Alaskan Time Zone (UTC-09:00), while Hawaii and parts of the Aleutian Islands have Hawaii-Aleutian Time Zone (UTC-09:00). For instance, Eastern Time refers to EST or EDT. The time zones observed by the 48 states use generic names, without highlighting the difference between DST and standard time designations. The DST is observed in all of the contiguous states except Arizona (observed only in the Navajo Nation). Washington, Nevada, California, and parts of Oregon and Idaho observe Pacific Time Zone (UTC-07:00) while the states straddled by the Rocky Mountains and Great Plains’ western quarter have Mountain Time Zone (UTC-06:00).