In the 19th century in America, time was determined by the sun. Towns and cities set their public clocks according to when the sun reached its zenith at “high noon.” Thus, even cities that were separated by only a few miles had their clocks set to different times. Railroad stations had multiple clocks, one for each railroad that used the station and one for local time.
Individuals had their choice of sources for the correct time: clocks on church towers and town halls, watches in jewelers’ windows, or factory whistles and bells. Large cities had time balls that would rise and drop every day at noon, by which city dwellers could set their watches; the ritual survives in the annual New Year’s event in Times Square.
Time became standardized when Western Union’s New York time ball dropped at noon on Sunday, November 18, 1883. Standard Railway Time was put into effect after a decade’s discussion among railroad executives, scientists, civil engineers and meteorologists, without benefit of either federal law or public demand.
Many cities and states resisted Standard Railway Time for years, for various political and religious reasons; these dissident voices were finally stilled, and Standard Railway Time made into federal law, with the Standard Time Act of 1918 – the first year in which the US also experimented with nationwide Daylight Savings Time.